217 results on '"Harper AM"'
Search Results
2. Local Cerebral Glucose Utilisation Following Indoleamine- and Piperazine-Containing 5-Hydroxytryptamine Agonists
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Harper Am and John J. Grome
- Subjects
Male ,Agonist ,Serotonin ,medicine.medical_specialty ,Methoxydimethyltryptamines ,medicine.drug_class ,Guinea Pigs ,Caudate nucleus ,Deoxyglucose ,Biology ,Biochemistry ,Cellular and Molecular Neuroscience ,Diencephalon ,chemistry.chemical_compound ,Internal medicine ,medicine ,Animals ,Behavior, Animal ,Brain ,Rats, Inbred Strains ,Metabolism ,Rats ,Lysergic Acid Diethylamide ,Piperazine ,Glucose ,Quipazine ,Endocrinology ,chemistry ,Pyrazines ,Receptors, Serotonin ,Quinolines ,Autoradiography ,Nucleus reuniens - Abstract
Substances with varying structural components have been shown to have 5-hydroxytryptamine (5-HT)-like properties in the CNS. In this study, putative 5-HT agonists with indoleamine moeities--lysergic acid diethylamide (LSD) and 5-methoxy-N,N-dimethyltryptamine (5-MeODMT)--and with piperazine moieties--quipazine (Quip) and 6-chloro-2-(1-piperazinyl)pyrazine (6-CPP) were administered to rats. Local cerebral glucose utilisation was measured using the [14C]2-deoxyglucose autoradiographic technique. It was found that in most cerebral structures, these substances produced dose-dependent reductions in glucose utilisation. However, Quip and 6-CPP increased glucose utilisation in specific areas of the diencephalon (e.g., nucleus reuniens) and produced a biphasic effect in some but not all extrapyramidal structures (e.g., ventromedial caudate nucleus). No such increases in local cerebral glucose utilisation were measured following LSD or 5-MeODMT administration. These results indicate that although similarities exist between the effects of indoleamine- and piperazine-containing 5-HT agonists on local cerebral glucose utilisation there are also significant differences in the overall patterns of response produced.
- Published
- 1986
- Full Text
- View/download PDF
3. INITIAL PROPOSAL FOR A UNIFORM MINIMAL RECORD OF DISABILITY
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McGeorge Ap, MacKenzie Et, W Fitch, Harper Am, David I. Graham, and Lars Edvinsson
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Sympathetic nervous system ,medicine.anatomical_structure ,Neurology ,business.industry ,Medicine ,Neurology (clinical) ,General Medicine ,business ,Neuroscience ,Cerebral autoregulation ,Cerebrovascular Circulation ,Homeostasis - Published
- 1981
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4. Measurement of Cerebral Blood Flow
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Harper Am
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medicine.medical_specialty ,Xenon ,Nitrous Oxide ,Indicator Dilution Techniques ,Veins ,Internal medicine ,Humans ,Medicine ,Cerebral Cortex ,Radioisotopes ,business.industry ,Krypton ,Arteries ,Spinal cord ,Cerebrovascular Circulation ,Anesthesiology and Pain Medicine ,medicine.anatomical_structure ,Spinal Cord ,Cerebral blood flow ,Regional Blood Flow ,Cerebral cortex ,Indicator dilution technique ,Cardiology ,Indicators and Reagents ,business ,Blood Flow Velocity ,Neck - Published
- 1969
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5. General Physiology of Cerebral Circulation
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Harper Am
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medicine.medical_specialty ,Blood viscosity ,Blood Pressure ,Hematocrit ,Autonomic Nervous System ,Nervous System ,Body Temperature ,Veins ,Cerebral circulation ,Dogs ,Mental Processes ,Cerebrospinal fluid ,Cerebellum ,Internal medicine ,Pressure ,Animals ,Humans ,Medicine ,Cerebrospinal Fluid ,Cerebral Cortex ,medicine.diagnostic_test ,business.industry ,Arteries ,Haplorhini ,Carbon Dioxide ,Hydrogen-Ion Concentration ,Blood Viscosity ,Sleep in non-human animals ,Cerebrovascular Circulation ,Capillaries ,Oxygen ,Blood ,Anesthesiology and Pain Medicine ,Blood pressure ,Regional Blood Flow ,Cats ,Cardiology ,Sleep ,business - Published
- 1969
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6. Measurement of liver blood flow in the dog using krypton-85 clearance: a comparison with electromagnetic flowmeter measurements
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Blumgart Lh, Harper Am, D. P. Leiberman, and Mathie Rt
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Radioisotopes ,Pathology ,medicine.medical_specialty ,Chemistry ,Krypton ,Blood flow ,Electromagnetic flowmeter ,Krypton-85 ,medicine.anatomical_structure ,Dogs ,Flow (mathematics) ,Liver tissue ,medicine ,Animals ,Surgery ,Liver blood flow ,Rheology ,Clearance rate ,Electromagnetic Phenomena ,Artery ,Biomedical engineering ,Liver Circulation - Abstract
Blood flow in the superficial liver tissue was measured by recording the clearance rate of the β emissions of 85 Kr following its injection into the portal vein. The flow values calculated from monoexponential clearance curves were compared to portal venous blood flow simultaneously recorded with a calibrated electromagnetic flow probe in six dogs whose hepatic artery had been ligated. The liver: blood partition coefficient of 85 Kr was measured in these dogs and was found to be 0.91. There was a close correlation ( r = 0.95) between the blood flow values obtained from the two techniques over a wide range of flow values. This shows that measurement of liver blood flow in the surface layers of the liver using the 85 Kr clearance method provides a true reflection of the blood flow in the liver tissue as a whole.
- Published
- 1978
7. The role of blood flow in the control of liver size
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Mathie Rt, Harper Am, Blumgart Lh, and D. P. Leiberman
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Radioisotopes ,business.industry ,Krypton ,Portal circulation ,Vein graft ,Anatomy ,Blood flow ,Organ Size ,Pancreatic Hormones ,Models, Biological ,Portal System ,medicine.anatomical_structure ,Dogs ,Liver ,medicine ,Upper gastrointestinal ,Animals ,Surgery ,Pancreas ,Splanchnic ,business ,Perfusion ,Liver size ,Liver Circulation - Abstract
Recent reports by Starzl [T. E. Starzl], A. Francavilla, C. G. Halgrimson, F. R. Francavilla, K. A. Porter, T. H. Brown, and C. W. Putman, Surg. Gynecol. Obstet.137: 179, 1973; T. E. Starzl, K. A. Porter, N. Kashiwagi, I. Y. Lee, W. J. I. Russell, and C. W. Putnam, Surg. Gynecol. Obstet.140: 549, 1975] have described a splanchnic flow division experiment in the dog, in which portal blood from the upper gastrointestinal tract (including pancreas) was directed to the right lobes of the liver, while the left lobes received blood exclusively from the intestines via a vein graft. It was shown that the right lobes increased in weight, whereas the left lobes atrophied, and it was concluded that portal blood contains hepatotrophic factors of pancreatic origin. In the present experiments, the possible existence of differences in blood flow in the two hepatic segments was examined as an alternative explanation for the changes observed. Tissue perfusion was measured by 85Kr clearance in the right and left hepatic lobes of five dogs 60 days after splanchnic division, and it was found that there was no difference between the flows through the two segments, while changes in liver weight similar to those of the previous workers were seen. The results therefore confirm the observations of Starzl that the size of the liver depends on its portal circulation, and is mainly related to the quality of the blood that it supplies to the liver rather than on quantity of flow.
- Published
- 1979
8. Application of pyrolysis/gas chromatography/pattern recognition to the detection of cystic fibrosis heterozygotes
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Harper Am, B.K. Lavine, Peter C. Jurs, J.A. Pino, and J.E. McMurry
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Male ,Pathology ,medicine.medical_specialty ,Pancreatic disease ,Chromatography, Gas ,Cystic Fibrosis ,Chemistry ,business.industry ,Genetic Carrier Screening ,Respiratory disease ,Heterozygote advantage ,medicine.disease ,Cystic fibrosis ,Analytical Chemistry ,Text mining ,Pattern recognition (psychology) ,medicine ,Humans ,Female ,Gas chromatography ,business ,Cells, Cultured - Published
- 1985
9. Adenosine response on pial arteries, influence of CO2 and blood pressure
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Boisvert Dp, Gregory Pc, and Harper Am
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Male ,medicine.medical_specialty ,Adenosine ,Physiology ,Clinical Biochemistry ,Vasodilation ,Blood Pressure ,pCO2 ,chemistry.chemical_compound ,Physiology (medical) ,Internal medicine ,medicine ,Animals ,Normocapnia ,CATS ,Chloralose ,Carbon Dioxide ,Hydrogen-Ion Concentration ,Vasomotor System ,Arterioles ,Blood pressure ,medicine.anatomical_structure ,chemistry ,Anesthesia ,Cardiology ,Vascular resistance ,Cats ,Pia Mater ,Female ,circulatory and respiratory physiology ,medicine.drug - Abstract
The television image-splitting technique was used to study the influence of arterial pCO2 and blood pressure on the dilatatory response of pial arterioles to topically applied adenosine in chloralose anaesthetised cats. At normocapnia (pCO2 congruent to 35 mm Hg) 10(-5) adenosine caused pial arteriole dilatation of 29.2 +/- 2.7% (S.E.M.). This was significantly reduced to 14.5 +/- 1.6% (P < 0.001) at pCO2 25 mm Hg and to 8.5 +/- 1.6% (P O 0.001) at pCO2 48 mm Hg. Lowering the blood pressure to 65--85 mm Hg had no significant effect on the adenosine response, but raising the blood pressure to 140--160 mm Hg significantly reduced the adenosine response to 22.1 +/- 1.8% (P < 0.005). The response was independent of vessel size except at hypertension where vessels < 150 micrometer were significantly more reactive than the larger vessels (P < 0.01). These results indicate that adenosine induced vasodilatation of pial arterioles shows little change in the face of alterations in vessel tone induced by altering blood pressure, but is markedly decreased by the combination of changing perivascular pH and vascular resistance through moderate changes in arterial pCO2. The importance of these results in assessing the role of adenosine as a cerebral vasodilator is discussed.
- Published
- 1980
10. The hepatic arterial and portal venous circulations of the liver studied with a krypton-85 clearance technique
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Harper Am, Mathie Rt, Blumgart Lh, and D. P. Leiberman
- Subjects
Radioisotopes ,Pathology ,medicine.medical_specialty ,business.industry ,Portal Vein ,Microcirculation ,Portal vein ,Krypton ,Bolus (medicine) ,medicine.anatomical_structure ,Dogs ,Hepatic Artery ,Hepatic parenchyma ,Medicine ,Animals ,Surgery ,Liver blood flow ,business ,Nuclear medicine ,Collateral vessels ,Clearance rate ,Artery ,Liver Circulation - Abstract
Previous animal studies of liver blood flow (LBF) with the radioactive inert gas clearance technique have shown that the clearance rate of gas after its injection into the hepatic artery (HA) is slower than following injection into the portal vein (PV). Separation of HA and PV blood in the hepatic sinusoids has been suggested as an explanation. In the present study, alternate bolus injections of 85 Kr were made into the PV and HA in two groups of dogs. In the first group, injection into the HA resulted in calculated LBF values 31% lower than those derived from PV injections. The second group was subjected to a dissection which isolated the liver from local recirculation of 85 Kr from HA to PV via collateral vessels. In this group, calculated LBF values were identical after PV and HA injections. This finding supports the concept that the hepatic parenchyma is perfused by mixed HA and PV blood.
- Published
- 1978
11. Blood flow and oxygen uptake of the cerebral cortex of the dog during anaesthesia with different volatile agents
- Author
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McDowall Dg and Harper Am
- Subjects
Trichloroethylene ,Anesthesia, General ,chemistry.chemical_compound ,Dogs ,Oxygen Consumption ,Methoxyflurane ,Medicine ,Animals ,Cerebral Cortex ,business.industry ,General Medicine ,Blood flow ,Oxygen uptake ,Cerebrovascular Circulation ,medicine.anatomical_structure ,Neurology ,chemistry ,Cerebral cortex ,Regional Blood Flow ,Anesthesia ,Neurology (clinical) ,Chloroform ,Halothane ,business ,Blood Flow Velocity ,medicine.drug - Published
- 1965
12. The effect of serotonin on cerebral and extracerebral blood flow with possible implications in migraine
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Deshmukh Vd and Harper Am
- Subjects
Serotonin ,Xenon ,External carotid artery ,Facial Muscles ,Cerebral circulation ,medicine.artery ,medicine ,Animals ,Normocapnia ,Radioisotopes ,business.industry ,General Medicine ,Blood flow ,Haplorhini ,Carbon Dioxide ,Stimulation, Chemical ,Neurology ,Cerebral blood flow ,Injections, Intra-Arterial ,Regional Blood Flow ,Anesthesia ,Renal blood flow ,Cerebrovascular Circulation ,Depression, Chemical ,Carotid Artery, External ,Neurology (clinical) ,medicine.symptom ,Internal carotid artery ,business ,Hypercapnia ,Electromagnetic Phenomena ,Blood Flow Velocity ,Carotid Artery, Internal ,Papio - Abstract
Serotonin (1 μg/kg/min) was infused into the internal or the external carotid artery in anaesthetised baboons. Blood flow through the carotid arteries was measured by electromagnetic flow probes. Cerebral blood flow was measured by the 133Xenon clearance method. Temporal muscle blood flow was measured from the clearance of 133Xenon following local injection into the muscle. The following results of the infusion of Serotonin were noted: 1) The blood flow through the external carotid artery and the temporal muscle increased by several hundred per cent. 2) The blood flow through the internal carotid artery was reduced by 57 %. 3) The cerebral blood flow was reduced by 17 % at normocapnia but by twice this figure at hypercapnia.
- Published
- 1973
13. The failure of intravenous urea to alter the blood flow through the cerebral cortex
- Author
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Bell Ra and Harper Am
- Subjects
Cerebral Cortex ,Pathology ,medicine.medical_specialty ,business.industry ,Hemodynamics ,Blood flow ,Metabolism ,Articles ,Psychiatry and Mental health ,chemistry.chemical_compound ,medicine.anatomical_structure ,chemistry ,Cerebral cortex ,Blood circulation ,Blood Circulation ,medicine ,Urea ,Humans ,Surgery ,Neurology (clinical) ,Tissue metabolism ,business ,Blood Flow Velocity - Published
- 1963
14. The measurement of local cortical blood flow in the brain by the analysis of the clearance curve of krypton-85
- Author
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Harper Am, Glover Mm, and Glass Hi
- Subjects
medicine.medical_specialty ,Radiological and Ultrasound Technology ,Computer science ,Krypton ,Brain ,Blood flow ,Surgery ,Krypton-85 ,Regional Blood Flow ,Blood circulation ,medicine ,Humans ,Radiology, Nuclear Medicine and imaging ,Biomedical engineering - Abstract
A new technique of measuring local cortical blood flow in the brain is described. The mathematical analysis relating the clearance curve to the blood flow is derived. The assumptions of the method are discussed and some preliminary results obtained using this technique are presented.
- Published
- 1961
15. Measurement of cerebral blood flow in man
- Author
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Harper Am
- Subjects
Radioisotopes ,medicine.medical_specialty ,business.industry ,Krypton ,Nitrous Oxide ,General Medicine ,030204 cardiovascular system & hematology ,Iodine Radioisotopes ,03 medical and health sciences ,0302 clinical medicine ,Text mining ,Cerebral blood flow ,Internal medicine ,Cerebrovascular Circulation ,Cardiology ,Methods ,Medicine ,Humans ,Indicators and Reagents ,030212 general & internal medicine ,business ,Blood Flow Velocity - Published
- 1967
16. Cerebral circulation and norepinephrine: relevance of the blood-brain barrier
- Author
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MacKenzie, ET, primary, McCulloch, J, additional, O'Kean, M, additional, Pickard, JD, additional, and Harper, AM, additional
- Published
- 1976
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17. Influence of endogenous norepinephrine on cerebral blood flow and metabolism
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MacKenzie, ET, primary, McCulloch, J, additional, and Harper, AM, additional
- Published
- 1976
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18. Great expectations? GPs' estimations of time required to deliver BMJ's '10 minute consultations'.
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Bradley SH, Harper AM, Smith L, Taylor N, Delap H, Pyke H, Girkin J, Sinnott C, and Watson J
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- Humans, State Medicine, Motivation, Referral and Consultation, Time Factors, General Practitioners
- Abstract
Objectives: To estimate the time required to undertake consultations according to BMJ's 10-minute consultation articles.To quantify the tasks recommended in 10-minute consultation articles.To determine if, and to what extent, the time required and the number of tasks recommended have increased over the past 22 years., Design: Analysis of estimations made by four general practitioners (GPs) of the time required to undertake tasks recommended in BMJ 's 10-minute consultation articles., Setting: Primary care in the UK., Participants: Four doctors with a combined total of 79 years of experience in the UK National Health Service following qualification as GPs., Main Outcome Measures: Median minimum estimated consultation length (the estimated time required to complete tasks recommended for all patients) and median maximum estimated consultation length (the estimated time required to complete tasks recommended for all patients and the additional tasks recommended in specific circumstances). Minimum, maximum and median consultation lengths reported for each year and for each 5-year period., Results: Data were extracted for 44 articles. The median minimum and median maximum estimated consultation durations were 15.7 minutes (IQR 12.6-20.9) and 28.4 minutes (IQR 22.4-33.8), respectively. A median of 17 tasks were included in each article. There was no change in durations required over the 22 years examined., Conclusions: The approximate times estimated by GPs to deliver care according to 10-minute consultations exceed the time available in routine appointments. '10 minute consultations' is a misleading title that sets inappropriate expectations for what GPs can realistically deliver in their routine consultations. While maintaining aspirations for high-quality care is appropriate, practice recommendations need to take greater account of the limited time doctors have to deliver routine care., Competing Interests: Competing interests: SHB, CS, NT, HD, HP, JG and JW are general practitioners (GP), while AH is a GP trainee., (© Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)
- Published
- 2024
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19. Understanding the patient's experience of coeliac disease diagnosis: a qualitative interview study.
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Harper AM, Watson J, O'Donnell R, Elwenspoek MM, and Banks J
- Subjects
- Adult, Humans, Diet, Gluten-Free, Biopsy methods, Surveys and Questionnaires, Qualitative Research, Celiac Disease diagnosis
- Abstract
Background: Coeliac disease (CD) presents with non-specific symptoms, and delays to diagnosis are common. The traditional diagnostic pathway involves serological testing followed by endoscopic biopsy; however, the evidence is increasing about the effectiveness of a diagnosis without the need for a biopsy., Aim: To understand the patient's experience of being diagnosed with CD., Design and Setting: A qualitative study was conducted, which involved semi-structured interviews with adults diagnosed with CD living in the UK., Method: Participants ( n = 20) were purposefully sampled from 200 adults who had completed a diagnostic confidence survey. Interviews were conducted via video-conferencing software (Zoom), recorded, and transcribed verbatim. Data were analysed using reflexive thematic analysis., Results: Interviewees faced pre-diagnostic uncertainty, presenting with non-specific symptoms that many experienced for several years and may have normalised. GPs often attributed their symptoms to alternative diagnoses, commonly, irritable bowel syndrome or anaemia. Investigations caused further uncertainty, with half of the interviewees unaware that their initial serology included a test for CD, and reporting long waits for endoscopy and challenges managing their diet around the procedure. Their uncertainty reduced once they received their biopsy results. Endoscopy was presented as the 'gold standard' for diagnosis and most interviewees believed that the procedure was necessary for diagnostic confidence and conviction in a lifelong gluten-free diet., Conclusion: Patients experience uncertainty on the pathway to a diagnosis of CD. GPs could improve their experiences by being mindful of the possibility of CD and sharing information about serological testing. Policy and guidance should address the time to endoscopy and diet during diagnosis. If diagnosis without biopsy is adopted, then consideration should be given to clinical pathway implementation and communication approaches to reduce patient uncertainty., (© The Authors.)
- Published
- 2024
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20. Navigating coeliac disease diagnosis in primary care.
- Author
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Harper AM, Banks J, Elwenspoek M, Lane D, Mousley K, Shiha MG, and Watson J
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- Humans, Primary Health Care, Celiac Disease diagnosis
- Published
- 2024
- Full Text
- View/download PDF
21. Preference for and reinforcing efficacy of different types of attention in preschool children.
- Author
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Harper AM, Dozier CL, Briggs AM, de Villegas SD, Ackerlund Brandt JA, and Jowett Hirst ES
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- Attention, Child, Preschool, Humans, Reinforcement Schedule, Choice Behavior, Reinforcement, Psychology
- Abstract
It is unknown whether and to what extent common types of attention delivered in early childhood environments are preferred by and function as reinforcers for young children. We assessed children's preference for commonly delivered types of attention across 31 preschool-aged participants (Experiment 1). Next, we conducted a reinforcer assessment (Experiment 2) and a progressive-ratio assessment (Experiment 3) to (a) validate the results of the preference assessment and (b) determine the relative reinforcing efficacy of each type of attention. Results of Experiment 1 showed that most participants preferred conversation or physical interaction. Results of Experiment 2 validated the results of Experiment 1 showing preferred types of attention were more likely to function as reinforcers. Finally, although some types of attention functioned as reinforcers, results of Experiment 3 indicated these reinforcers only maintained responding under relatively dense schedules of reinforcement. Clinical implications and directions for future research are discussed., (© 2021 Society for the Experimental Analysis of Behavior.)
- Published
- 2021
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22. Seeing New Opportunities to Help Smokers Quit: A UK National Survey of Optometrist-Delivered Smoking Cessation Behavioral Support Interventions.
- Author
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Lorencatto F, Asif S, Francis JJ, Harper AM, and Lawrenson JG
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- Adult, Attitude of Health Personnel, Female, Humans, Male, Middle Aged, Random Allocation, Risk Factors, Tobacco Smoking psychology, Tobacco Smoking therapy, United Kingdom epidemiology, Behavior Therapy methods, Optometrists psychology, Smokers psychology, Smoking Cessation methods, Smoking Cessation psychology, Surveys and Questionnaires
- Abstract
Background: Smoking is a risk factor for various eye conditions. Brief smoking cessation interventions have demonstrated effectiveness when delivered by a range of health care professionals. Optometrists are well placed in the community to advise otherwise healthy smokers to quit, yet remain relatively neglected in smoking cessation research and policy. In a national survey, this study investigated self-reported practices of UK optometrists for delivering brief tobacco smoking cessation interventions to patients., Methods: A randomly selected sample of 1200 optometrists out of the 9000 optometrists registered on the UK College of Optometrists database were invited to complete a 40-item, web-based survey assessing: training related to smoking cessation, current practice (ie, the proportion of patients to which components of very brief advice [Ask, Advise, Assist] and other evidence-based smoking cessation behavior change techniques were delivered), and barriers/enablers to intervention delivery., Results: In total, 408 (34%) responses were received. Most (83%) optometrists received no training in practical skills for delivering smoking cessation support. A third (34%) routinely assessed smoking status. Fewer self-reported advising smokers to quit (22%), offering assistance (via referral to dedicated services) (3%), or advice on smoking cessation medications (2%). Perceived barriers included insufficient knowledge/training (81%) and time (65%). Optometrists were more likely to assess and advise on smoking cessation if they practiced in Scotland, χ2(2) = 32.95, p < .001; an independent optometry practice, χ2(1) = 4.27, p = .39; or had received smoking cessation training, χ2(1) = 13.1, p < .001., Conclusions: Substantial gaps exist in UK optometrists' current smoking cessation training and practice. Evidence-based training resources are needed to support the implementation of smoking cessation interventions into routine optometry practice., Implications: Optometrists are well placed in the community to deliver brief advice interventions to a large population of smokers. This survey provides a comprehensive description of current UK optometry practice related to the provision of evidence-based brief tobacco smoking cessation interventions to patients. Although optometrists perceive advising on smoking cessation as part of their role, numerous substantial gaps in current practice and training remain, which need to be addressed through targeted interventions to increase implementation., (© The Author(s) 2018. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)
- Published
- 2019
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23. Early Liver Transplantation is a Viable Treatment Option in Severe Acute Alcoholic Hepatitis.
- Author
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Puri P, Cholankeril G, Myint TY, Goel A, Sarin SK, Harper AM, and Ahmed A
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- Adult, Databases, Factual trends, Female, Hepatitis, Alcoholic diagnosis, Hepatitis, Alcoholic mortality, Humans, Liver Transplantation mortality, Male, Middle Aged, Retrospective Studies, Risk Factors, Survival Rate trends, Hepatitis, Alcoholic surgery, Liver Transplantation trends, Severity of Illness Index, Time-to-Treatment trends, Waiting Lists mortality
- Abstract
Liver transplantation is lifesaving for patients with severe acute alcoholic hepatitis (SAH) with preliminary data demonstrating favorable early post-transplant outcomes. Using the United Network for Organ Sharing database, we demonstrate that liver transplantation for SAH in the USA has steadily increased and is associated with similar 1- and 3-year post-transplant survival as well as comparable 30-day waitlist mortality to acute liver failure due to drug-induced liver injury.
- Published
- 2018
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24. Considerations on accuracy, pattern and possible underlying factors of brain microbleed progression in older adults with absence or mild presence of vascular pathology.
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Harper AM, Clayson L, Wardlaw JM, and Valdés Hernández MDC
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- Aged, Aged, 80 and over, Cross-Sectional Studies, Disease Progression, Female, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Observer Variation, Alzheimer Disease diagnostic imaging, Cognitive Dysfunction diagnostic imaging, Intracranial Hemorrhages diagnostic imaging, Vascular Diseases diagnostic imaging
- Abstract
Objective To analyse brain microbleed (BMB) progression, its possible underlying factors, and the influence of inter-observer differences, in older individuals with none or mild vascular pathology. Methods This study analysed magnetic resonance images, cognitive, demographic and laboratory data from all individuals from the Alzheimer's Disease (AD) Neuroimaging Initiative database who had the required sequences for identifying BMBs over three consecutive years at the time the database was accessed (January 2016). BMBs were assessed independently by two observers with similar levels of experience. Results A total of 291 patients were included in the study. The number of individuals with BMBs and the number of BMBs per individual slightly and nonsignificantly increased across three consecutive years (Y1: 55/291 [19%]; Y2: 61/291 [21%]; Y3: 66/291 [23%]) with 1-2 BMBs and (Y1: 11/291 [4%]; Y2: 12/291 [4%]; Y3: 14/291 [5%]) with ≥ 3 BMBs. Both observers identified a similar pattern of BMB prevalence and progression in each cognitive group (normal < early/late mild cognitive impairment (MCI) > AD patients) despite inter-observer differences (1.5 BMBs, 95% confidence interval -3.7, 6.2], κ=0.543), which were mainly in the cortex. Serum cholesterol was the main predictor of change in BMB count between time-points but did not predict overall progression. Conclusions Inter-observer differences are always present and it is difficult to ascertain their influence in the analysis of BMB progression, which was observed in cognitively normal and MCI individuals, but not in AD patients. This should be confirmed in further studies.
- Published
- 2018
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25. Measuring and monitoring equity in access to deceased donor kidney transplantation.
- Author
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Stewart DE, Wilk AR, Toll AE, Harper AM, Lehman RR, Robinson AM, Noreen SA, Edwards EB, and Klassen DK
- Subjects
- Adult, Cadaver, Female, Follow-Up Studies, Humans, Kidney Failure, Chronic surgery, Male, Middle Aged, Prognosis, Registries, Survival Rate, Transplant Recipients, Health Care Rationing standards, Kidney Transplantation mortality, Resource Allocation trends, Tissue Donors supply & distribution, Tissue and Organ Procurement trends, Waiting Lists mortality
- Abstract
The Organ Procurement and Transplantation Network monitors progress toward strategic goals such as increasing the number of transplants and improving waitlisted patient, living donor, and transplant recipient outcomes. However, a methodology for assessing system performance in providing equity in access to transplants was lacking. We present a novel approach for quantifying the degree of disparity in access to deceased donor kidney transplants among waitlisted patients and determine which factors are most associated with disparities. A Poisson rate regression model was built for each of 29 quarterly, period-prevalent cohorts (January 1, 2010-March 31, 2017; 5 years pre-kidney allocation system [KAS], 2 years post-KAS) of active kidney waiting list registrations. Inequity was quantified as the outlier-robust standard deviation (SD
w ) of predicted transplant rates (log scale) among registrations, after "discounting" for intentional, policy-induced disparities (eg, pediatric priority) by holding such factors constant. The overall SDw declined by 40% after KAS implementation, suggesting substantially increased equity. Risk-adjusted, factor-specific disparities were measured with the SDw after holding all other factors constant. Disparities associated with calculated panel-reactive antibodies decreased sharply. Donor service area was the factor most associated with access disparities post-KAS. This methodology will help the transplant community evaluate tradeoffs between equity and utility-centric goals when considering new policies and help monitor equity in access as policies change., (© 2018 The American Society of Transplantation and the American Society of Transplant Surgeons.)- Published
- 2018
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26. OPTN/SRTR 2016 Annual Data Report: Intestine.
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Smith JM, Weaver T, Skeans MA, Horslen SP, Harper AM, Snyder JJ, Israni AK, and Kasiske BL
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- Humans, Registries, Tissue Donors, United States, Annual Reports as Topic, Graft Survival, Intestines transplantation, Resource Allocation, Tissue and Organ Procurement, Waiting Lists
- Abstract
Despite improvements in medical and surgical treatment of intestinal failure, intestine transplant continues to play an important role. In 2016, a total of 147 intestine transplants were performed, 80 intestine-without-liver and 67 intestine-liver. Over the past decade, the age distribution of candidates waitlisted for intestine and intestine-liver transplant shifted from primarily pediatric to increasing proportions of adults. In 2016, 58.2% of candidates on the intestine list at any time during the year were aged younger than 18 years, with a decrease over time in those aged younger than 6 years and an increase in those aged 6-17 years. Adults accounted for 41.9% of candidates on the list at any time during the year, with a stable proportion of those aged 18-34 years and a decrease in those aged 35 years or older. By age, pretransplant mortality rate was highest for adult candidates at 11.7 per 100 waitlist years and lowest for children aged younger than 6 years at 2.2 per 100 waitlist years. For intestine transplants with or without a liver in 2009-2011, 1- and 5-year graft survival was 72.0% and 54.1%, respectively, for recipients aged younger than 18 years, and 70.5% and 44.1%, respectively, for recipients aged 18 years or older., (.)
- Published
- 2018
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27. OPTN/SRTR 2016 Annual Data Report: Liver.
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Kim WR, Lake JR, Smith JM, Schladt DP, Skeans MA, Harper AM, Wainright JL, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Humans, Registries, Tissue Donors, United States, Annual Reports as Topic, Graft Survival, Liver Transplantation, Tissue and Organ Procurement, Waiting Lists
- Abstract
Data on adult liver transplants performed in the US in 2016 are no-table for (1) the largest total number of transplants performed (7841); (2) the shortest median waiting time in recent history (11.3 months); (3) continued reduction in waitlist registrations and transplants for hepatitis C-related indications; (4) increasing numbers of patients whose clinical profiles are consistent with non-alcoholic fatty liver disease; and (5) equilibration of transplant rates in patients with and without hepatocellular carcinoma. Despite the increase in the number of available organs, waitlist mortality remained an important concern. Graft survival rates continued to improve. In 2016, 723 new active candidates were added to the pediatric liver transplant waiting list, down from a peak of 826 in 2005. The number of prevalent candidates (on the list on December 31 of the given year) was stable, 408 active and 169 inactive. The number of pediatric living donor liver transplants decreased from a peak of 79 in 2015 to 62 in 2016, with most from donors closely related to the recipients. Graft survival continued to improve over the past decade among recipients of deceased donor and living donor livers., (.)
- Published
- 2018
- Full Text
- View/download PDF
28. OPTN/SRTR 2015 Annual Data Report: Liver.
- Author
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Kim WR, Lake JR, Smith JM, Skeans MA, Schladt DP, Edwards EB, Harper AM, Wainright JL, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Humans, Immunosuppressive Agents, Treatment Outcome, United States, Waiting Lists, Annual Reports as Topic, Graft Survival, Liver Transplantation, Resource Allocation, Tissue Donors supply & distribution, Tissue and Organ Procurement methods
- Abstract
Several notable developments in adult liver transplantation in the US occurred in 2015. The year saw the largest number of liver transplants to date, leading to reductions in median waiting time, in waitlist mortality for all model for end-stage liver disease categories, and in the number of candidates on the waiting list at the end of the year. Numbers of additions to the waiting list and of liver transplants performed in patients with hepatitis C virus infection decreased for the first time in recent years. However, other diagnoses, such as non-alcoholic fatty liver disease and alcoholic cirrhosis, became more prevalent. Despite large numbers of severely ill patients undergoing liver transplant, graft survival rates continued to improve. The number of new active candidates added to the pediatric liver transplant waiting list in 2015 was 689, down from a peak of 826 in 2005. The number of prevalent pediatric candidates (on the list on December 31 of the given year) continued to decline, to 373 active and 195 inactive candidates. The number of pediatric liver transplants peaked at 613 in 2008 and was 580 in 2015. The number of living donor pediatric liver transplants increased to its highest level, 79, in 2015; most were from donors closely related to the recipients. Pediatric graft survival rates continued to improve., (.)
- Published
- 2017
- Full Text
- View/download PDF
29. OPTN/SRTR 2015 Annual Data Report: Intestine.
- Author
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Smith JM, Skeans MA, Horslen SP, Edwards EB, Harper AM, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Humans, Immunosuppressive Agents, Treatment Outcome, United States, Waiting Lists, Annual Reports as Topic, Graft Survival, Intestines transplantation, Resource Allocation, Tissue Donors supply & distribution, Tissue and Organ Procurement methods
- Abstract
Intestine and intestine-liver transplant remains important in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2015, 196 new patients were added to the intestine transplant waiting list, with equal numbers waiting for intestine and intestine-liver transplant. Among prevalent patients on the list at the end of 2015, 63.3% were waiting for an intestine transplant and 36.7% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was notably higher for intestine-liver than for intestine transplant candidates (respectively, 19.9 vs. 2.8 deaths per 100 waitlist years in 2014-2015). By age, pretransplant mortality was highest for adult candidates, at 19.6 per 100 waitlist years, and lowest for children aged younger than 6 years, at 3.6 per 100 waitlist years. Pretransplant mortality by etiology was highest for candidates with non-congenital types of short-gut syndrome. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 70 in 2015. Intestine-liver transplants increased from a low of 44 in 2012 to 71 in 2015. Short-gut syndrome (congenital and non-congenital) was the main cause of disease leading to intestine and to intestine-liver transplant. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients., (.)
- Published
- 2017
- Full Text
- View/download PDF
30. A survey of UK optometry trainees' smoking cessation training.
- Author
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Lorencatto F, Harper AM, Francis JJ, and Lawrenson JG
- Subjects
- Female, Humans, Incidence, Male, Risk Factors, United Kingdom epidemiology, Attitude of Health Personnel, Education, Medical, Undergraduate methods, Optometry education, Smoking epidemiology, Smoking Cessation methods
- Abstract
Background: Smoking is a risk factor for a number of eye conditions, including age-related macular degeneration, cataracts and thyroid eye disease. Smoking cessation interventions have been shown to be highly cost-effective when delivered by a range of healthcare professionals. Optometrists are well placed to deliver smoking cessation advice to a wide population of otherwise healthy smokers. Yet optometrists remain a relatively neglected healthcare professional group in smoking cessation research and policy. Surveys of UK medical/nursing schools and of optometrists' training internationally demonstrate significant deficits in current curricular coverage regarding smoking cessation. This study aimed to identify the extent of smoking cessation training in UK optometry trainees' undergraduate and pre-registration training., Methods: All undergraduate optometry schools in the UK (n = 9) were invited to participate in a web-based survey of their curricular coverage and assessment related to smoking cessation, and of perceived barriers to delivering smoking cessation training. A content analysis of the College of Optometrists Scheme for Registration Trainee Handbook 2014 was conducted to identify competence indicators related to smoking cessation., Results: Nine undergraduate optometry schools (100%) responded to the survey. The majority reported dedicating limited hours (0-3) to teaching smoking cessation, and predominantly focused on teaching the harmful effects of smoking (89%). Only one school provides practical skills training for delivering evidence-based smoking cessation interventions, including very brief advice. The majority of schools (78%) reported that they did not formally examine students on their knowledge or skills for supporting smoking cessation, and rated confidence in their graduates' abilities to deliver smoking cessation interventions as 'poor' (78%). Lack of knowledge amongst staff was identified as the key barrier to teaching about smoking cessation support. The pre-registration competency framework does not include any competence indicators related to providing support for quitting smoking., Conclusions: There are substantial gaps in the current curricula of UK optometry training, particularly regarding practical skills for supporting smoking cessation. Increased curricular coverage of these issues is essential to ensure trainee optometrists are adequately trained and competent in supporting patients to quit smoking., (© 2016 The Authors. Ophthalmic and Physiological Optics published by John Wiley & Sons Ltd on behalf of College of Optometrists.)
- Published
- 2016
- Full Text
- View/download PDF
31. An early look at the Organ Procurement and Transplantation Network explant pathology form data.
- Author
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Harper AM, Edwards E, Washburn WK, and Heimbach J
- Subjects
- Age Factors, Carcinoma, Hepatocellular diagnostic imaging, Carcinoma, Hepatocellular pathology, Cohort Studies, Early Detection of Cancer, Female, Humans, Liver pathology, Liver Neoplasms diagnostic imaging, Liver Neoplasms pathology, Male, Middle Aged, Neoplasm Staging, Risk Factors, Sex Factors, Time Factors, Tumor Burden, Waiting Lists, alpha-Fetoproteins analysis, Carcinoma, Hepatocellular surgery, Liver Neoplasms surgery, Liver Transplantation, Neoplasm Recurrence, Local epidemiology, Tissue and Organ Procurement standards
- Abstract
In April 2012, the Organ Procurement and Transplantation Network (OPTN) implemented an online explant pathology form for recipients of liver transplantation who received additional wait-list priority for their diagnosis of hepatocellular carcinoma (HCC). The purpose of the form was to standardize the data being reported to the OPTN, which had been required since 2002 but were submitted to the OPTN in a variety of formats via facsimile. From April 2012 to December 2014, over 4500 explant forms were submitted, allowing for detailed analysis of the characteristics of the explanted livers. Data from the explant pathology forms were used to assess agreement with pretransplant imaging. Explant data were also used to assess the risk of recurrence. Of those with T2 priority, 55.7% were found to be stage T2 on explant. Extrahepatic spread (odds ratio [OR] = 6.8; P < 0.01), poor tumor differentiation (OR = 2.8; P < 0.01), microvascular invasion (OR = 2.6; P < 0.01), macrovascular invasion (OR = 3.2; P < 0.01), and whether the Milan stage based on the number and size of tumors on the explant form was T4 (OR = 2.4; P < 0.01) were the strongest predictors of recurrence. In conclusion, this analysis confirms earlier findings that showed an incomplete agreement between pretransplant imaging and posttransplant pathology in terms of HCC staging, though the number of patients with both no pretransplant treatment and no tumor in the explant was reduced from 20% to <1%. In addition, several factors were identified (eg, tumor burden, age, sex, region, ablative therapy, alpha-fetoprotein, Milan stage, vascular invasion, satellite lesions, etc.) that were predictive of HCC recurrence, allowing for more targeted surveillance of high-risk recipients. Continued evaluation of these data will help shape future guidelines or policy recommendations. Liver Transplantation 22 757-764 2016 AASLD., (© 2016 American Association for the Study of Liver Diseases.)
- Published
- 2016
- Full Text
- View/download PDF
32. The impact of broader regional sharing of livers: 2-year results of "Share 35".
- Author
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Edwards EB, Harper AM, Hirose R, and Mulligan DC
- Subjects
- Child, Cold Ischemia statistics & numerical data, Female, Graft Survival, Health Impact Assessment statistics & numerical data, Humans, Liver Failure mortality, Male, Middle Aged, Tissue Donors statistics & numerical data, Treatment Outcome, Liver Failure surgery, Liver Transplantation statistics & numerical data, Tissue and Organ Procurement methods, Waiting Lists mortality
- Abstract
In June of 2013, the Organ Procurement and Transplantation Network (OPTN) implemented regional sharing for Model for End-Stage Liver Disease (MELD)/Pediatric End-Stage Liver Disease (PELD) candidates with scores reaching 35 and above ("Share 35"). The goal of this distribution change was to increase access to lifesaving transplants for the sickest candidates with chronic liver disease and to reduce the waiting-list mortality for this medically urgent group of patients. To assess the impact of this change, we compared results before and after policy implementation at 2 years. Overall, there were more liver transplants performed under Share 35 and a greater percentage of MELD/PELD 35+ candidates underwent transplantation; waiting-list mortality rates in this group were also significantly lower in the post-policy period. Overall adjusted waiting-list mortality was decreased slightly, with no significant changes in mortality by age group or ethnicity. Posttransplant graft and patient survival was unchanged overall and was unchanged for the MELD/PELD 35+ recipients. In conclusion, these data demonstrate that the Share 35 policy achieved its goal of increasing access to transplants for these medically urgent patients without reducing access to liver transplants for pediatric and minority candidates. Although the variance in the median MELD at transplant as well as the variance in transport distance increased, there was a decrease in overall liver discard rates and no change in overall cold ischemia times following broader sharing of these organs. The OPTN will continue to monitor this policy, particularly for longer-term posttransplant survival outcomes., (© 2016 American Association for the Study of Liver Diseases.)
- Published
- 2016
- Full Text
- View/download PDF
33. Intestine.
- Author
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Smith JM, Skeans MA, Horslen SP, Edwards EB, Harper AM, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Female, Graft Survival, Humans, Immunosuppressive Agents, Male, Middle Aged, Prevalence, Tissue Donors, Treatment Outcome, United States, Waiting Lists, Young Adult, Intestinal Diseases surgery, Intestines surgery, Intestines transplantation, Liver Transplantation methods, Liver Transplantation statistics & numerical data
- Abstract
Intestine and intestine-liver transplant plays an important role in the treatment of intestinal failure, despite decreased morbidity associated with parenteral nutrition. In 2014, 210 new patients were added to the intestine transplant waiting list. Among prevalent patients on the list at the end of 2014, 65% were waiting for an intestine transplant and 35% were waiting for an intestine-liver transplant. The pretransplant mortality rate decreased dramatically over time for all age groups. Pretransplant mortality was highest for adult candidates, at 22.1 per 100 waitlist years compared with less than 3 per 100 waitlist years for pediatric candidates, and notably higher for candidates for intestine-liver transplant than for candidates for intestine transplant without a liver. Numbers of intestine transplants without a liver increased from a low of 51 in 2013 to 67 in 2014. Intestine-liver transplants increased from a low of 44 in 2012 to 72 in 2014. Short-gut syndrome (congenital and other) was the main cause of disease leading to both intestine and intestine-liver transplant. Graft survival improved over the past decade. Patient survival was lowest for adult intestine-liver recipients and highest for pediatric intestine recipients., (© Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2016
- Full Text
- View/download PDF
34. Liver.
- Author
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Kim WR, Lake JR, Smith JM, Skeans MA, Schladt DP, Edwards EB, Harper AM, Wainright JL, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Adolescent, Adult, Aged, Child, Child, Preschool, End Stage Liver Disease epidemiology, Graft Survival, Humans, Immunosuppressive Agents therapeutic use, Living Donors, Middle Aged, Time Factors, Tissue Donors, Treatment Outcome, United States, Waiting Lists, Young Adult, End Stage Liver Disease surgery, Liver Transplantation methods, Liver Transplantation statistics & numerical data
- Abstract
The median waiting time for patients with MELD ≥ 35 decreased from 18 days in 2012 to 9 days in 2014, after implementation of the Share 35 policy in June 2013. Similarly, mortality among candidates listed with MELD ≥ 35 decreased from 366 per 100 waitlist years in 2012 to 315 in 2014. The number of new active candidates added to the pediatric liver transplant waiting list in 2014 was 655, down from a peak of 826 in 2005. The number of prevalent candidates (on the list on December 31 of the given year) continued to decline, 401 active and 173 inactive. The number of deceased donor pediatric liver transplants peaked at 542 in 2008 and was 478 in 2014. The number of living donor liver pediatric transplants was 52 in 2014; most were from donors closely related to the recipients. Graft survival continued to improve among pediatric recipients of deceased donor and living donor livers., (© Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2016
- Full Text
- View/download PDF
35. Liver transplantation for hepatocellular carcinoma: analysis of factors predicting outcome in 1074 patients in OPTN Region 5.
- Author
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Macdonald B, Sewell JL, Harper AM, Roberts JP, and Yao FY
- Subjects
- Adult, Aged, Carcinoma, Hepatocellular mortality, Databases, Factual, Female, Humans, Kaplan-Meier Estimate, Liver Neoplasms mortality, Logistic Models, Male, Middle Aged, Multivariate Analysis, Neoplasm Recurrence, Local etiology, Retrospective Studies, Risk Factors, Treatment Outcome, Carcinoma, Hepatocellular surgery, Liver Neoplasms surgery, Liver Transplantation
- Abstract
Previous studies on loco-regional therapy (LRT) and alpha-fetoprotein (AFP) in predicting outcome after liver transplant (LT) for hepatocellular carcinoma (HCC) have shown inconsistent results. We analyzed the OPTN database in Region 5 from January 2004 to January 2009 and performed univariate and multivariate analysis of 11 pre-transplant recipient and donor variables in 1074 patients with HCC meeting Milan criteria to detect association with post-LT tumor recurrence or mortality. Mean waitlist time was 438 d. The 1- and 5-yr post-LT survival was 91.1% and 71.1%, respectively. In multivariate analysis, AFP before LT was the only predictor of HCC recurrence. The association between AFP and HCC recurrence was observed only in the subgroup receiving LRT but not in the subgroup without LRT. Predictors of mortality in multivariate analysis were HCC recurrence, Donor Risk Index, last AFP before LT, and MELD score. AFP before LT was the strongest predictor of post-transplant HCC recurrence or death in multivariate analysis. In conclusion, in Region 5 with prolonged waitlist time, high AFP was the only pre-transplant variable predicting post-transplant tumor recurrence and mortality for HCC meeting Milan criteria. Our results also supported the importance of the effects of LRT on AFP in predicting prognosis., (© 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)
- Published
- 2015
- Full Text
- View/download PDF
36. OPTN/SRTR 2013 Annual Data Report: intestine.
- Author
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Smith JM, Skeans MA, Horslen SP, Edwards EB, Harper AM, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Adolescent, Adult, Child, Female, Graft Survival, Humans, Intestinal Diseases mortality, Liver Transplantation, Male, Middle Aged, Organ Transplantation statistics & numerical data, Patient Readmission, Resource Allocation, Survival Rate, Treatment Outcome, United States, Young Adult, Annual Reports as Topic, Intestinal Diseases surgery, Intestines transplantation, Tissue Donors, Waiting Lists
- Abstract
Despite improvements in medical and surgical treatment of intestinal failure over the past decade, intestine transplant continues to play an important role. Of 171 new patients added to the intestine transplant waiting list in 2013, 49% were listed for intestine-liver transplant and 51% for intestine transplant alone or with an organ other than liver. The pretransplant mortality rate decreased dramatically over time for all age groups, from 30.3 per 100 waitlist years in 2002-2003 to 6.9 for patients listed in 2012-2013. The number of intestine transplants decreased from 91 in 2009 to 51 in 2013; intestine-liver transplants decreased from 135 in 2007 to a low of 44 in 2012, but increased slightly to 58 in 2013. Ages of intestine and intestineliver transplant recipients have changed substantially; the number of adult recipients was double the number of pediatric recipients in 2013. Graft survival improved over the past decade. Graft failure in the first 90 days posttransplant occurred in 14.1% of intestine recipients and in 11.2% of intestine-liver recipients in 2013. The number of recipients alive with a functioning intestine graft has steadily increased since 2002, to 1012 in 2013; almost half were pediatric intestine-liver transplant recipients., (© Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2015
- Full Text
- View/download PDF
37. OPTN/SRTR 2013 Annual Data Report: liver.
- Author
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Kim WR, Lake JR, Smith JM, Skeans MA, Schladt DP, Edwards EB, Harper AM, Wainright JL, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Adolescent, Adult, Aged, Child, Child, Preschool, Female, Graft Survival, Humans, Infant, Infant, Newborn, Liver Transplantation mortality, Male, Middle Aged, Patient Readmission, Survival Rate, Treatment Outcome, United States, Young Adult, Annual Reports as Topic, Liver Diseases surgery, Liver Transplantation statistics & numerical data, Resource Allocation, Tissue Donors, Waiting Lists
- Abstract
During 2013, 10,479 adult candidates were added to the liver transplant waiting list, compared with 10,185 in 2012; 5921 liver transplants were performed, and 211 of the transplanted organs were from living donors. As of December 31, 2013, 15,027 candidates were registered on the waiting list, including 12,407 in active status. The most significant change in allocation policy affecting liver waitlist trends in 2013 was the Share 35 policy, whereby organs from an entire region are available to candidates with model for end-stage liver disease scores of 35 or higher. Median waiting time for such candidates decreased dramatically, from 14.0 months in 2012 to 1.4 months in 2013, but the effect on waitlist mortality is unknown. The number of new active pediatric candidates added to the liver transplant waiting list increased to 693 in 2013. Transplant rates were highest for candidates aged younger than 1 year (275.6 per 100 waitlist years) and lowest for candidates aged 11 to 17 years (97.0 per 100 waitlist years). Five-year graft survival was 71.7% for recipients aged younger than 1 year, 74.9% for ages 1 to 5 years, 78.9% ages 6 to 10 years, and 77.4% for ages 11 to 17 years., (© Copyright 2015 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2015
- Full Text
- View/download PDF
38. OPTN/SRTR 2012 Annual Data Report: liver.
- Author
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Kim WR, Smith JM, Skeans MA, Schladt DP, Schnitzler MA, Edwards EB, Harper AM, Wainright JL, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Adult, Child, Cytomegalovirus Infections immunology, Epstein-Barr Virus Infections immunology, Graft Rejection, Hepatitis B Core Antigens analysis, Hepatitis B Surface Antigens analysis, Hepatitis C immunology, Humans, Living Donors, Patient Readmission statistics & numerical data, Postoperative Complications, Tissue Donors, Tissue and Organ Procurement, Treatment Outcome, United States epidemiology, Waiting Lists mortality, Liver Transplantation adverse effects, Liver Transplantation economics
- Abstract
Liver transplant in the us remains a successful life-saving procedure for patients with irreversible liver disease. In 2012, 6256 adult liver transplants were performed, and more than 65,000 people were living with a transplanted liver. The number of adults who registered on the liver transplant waiting list decreased for the first time since 2002; 10,143 candidates were added, compared with 10,359 in 2011. However, the median waiting time for active wait-listed adult candidates increased, as did the number of candidates removed from the list because they were too sick to undergo transplant. The overall deceased donor transplant rate decreased to 42.3 per 100 patient-years, and varied geographically from 18.9 to 228.0 per 100 patient-years. Graft survival continues to improve, especially for donation after circulatory death livers. The number of new active pediatric candidates added to the waiting list also decreased. Almost 75% of pediatric candidates listed in 2009 underwent transplant within 3 years; the 2012 rate of deceased donor transplants among active pediatric wait-listed candidates was 136 per 100 patient-years. Graft survival for deceased donor pediatric transplants was 92.8% at 30 days. Medicare paid for some or all of the care for more than 30% of liver transplants in 2010., (© Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2014
- Full Text
- View/download PDF
39. OPTN/SRTR 2012 Annual Data Report: intestine.
- Author
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Smith JM, Skeans MA, Horslen SP, Edwards EB, Harper AM, Snyderf JJ, Israni AK, and Kasiske BL
- Subjects
- Adolescent, Adult, Child, Child, Preschool, Graft Survival, Humans, Intestines surgery, Liver Transplantation, Patient Readmission, Short Bowel Syndrome surgery, Treatment Outcome, Waiting Lists mortality, Intestines transplantation
- Abstract
Advances in the medical and surgical treatments of intestinal failure have led to a decrease in the number of transplants over the past decade. In 2012, 152 candidates were added to the intestinal transplant waiting list, a new low. Of these, 64 were listed for intestine-liver transplant and 88 for intestinal transplant alone or with an organ other than liver. Historically, the most common organ transplanted with the intestine was the liver; this practice decreased substantially from a peak of 52.9% in 2007 to 30.0% in 2012. Short-gut syndrome, which encompasses a large group of diagnoses, is the most common etiology of intestinal failure. The pretransplant mortality rate decreased dramatically over time for all age groups, from 51.0 per 100 wait-list years in 1998-1999 to 6.7 for patients listed in 2010-2012. Numbers of intestinal and intestine-liver transplants steadily decreased from 198 in 2007 to 106 in 2012. By age, intestinal transplant recipients have changed substantially; the number of adult recipients now approximately equals the number of pediatric recipients. Graft survival has improved over the past decade. Graft failure in the first 90 days after transplant occurred in 15.7% of 2011-2012 intestinal transplant recipients, compared with 21% in 2001-2002., (© Copyright 2013 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2014
- Full Text
- View/download PDF
40. MELD score, allocation, and distribution in the United States.
- Author
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Wedd JP, Harper AM, and Biggins SW
- Published
- 2013
- Full Text
- View/download PDF
41. Functional analysis and treatment of problem behavior in early education classrooms.
- Author
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Greer BD, Neidert PL, Dozier CL, Payne SW, Zonneveld KL, and Harper AM
- Subjects
- Behavioral Symptoms psychology, Child, Preschool, Female, Humans, Infant, Male, Behavior Therapy methods, Behavioral Symptoms therapy, Education of Persons with Intellectual Disabilities methods, Reinforcement, Psychology
- Abstract
We conducted functional analyses (FA) with 4 typically developing preschool children during ongoing classroom activities and evaluated treatments that were based on FA results. Results of each child's FA suggested social-positive reinforcement functions, and differential reinforcement of alternative behavior plus time-out was effective in decreasing problem behavior and increasing appropriate behavior. We discuss the utility of classroom-based FAs and potential compromises to experimental control., (© Society for the Experimental Analysis of Behavior.)
- Published
- 2013
- Full Text
- View/download PDF
42. OPTN/SRTR 2011 Annual Data Report: liver.
- Author
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Kim WR, Stock PG, Smith JM, Heimbach JK, Skeans MA, Edwards EB, Harper AM, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Humans, Immunosuppressive Agents administration & dosage, Living Donors, Tissue Donors, Waiting Lists, Liver Transplantation
- Abstract
The current liver allocation system, introduced in 2002, decreased the importance of waiting time for allocation priorities; the number of active wait-listed candidates and median waiting times were immediately reduced. However, the total number of adult wait-listed candidates has increased since 2002, and median waiting time has increased since 2006. Pretransplant mortality rates have been stable, but the number of candidates withdrawn from the list as being too sick to undergo transplant nearly doubled between 2009 and 2011. Deceased donation rates have remained stable, with an increasing proportion of expanded criteria donors. Living donation has decreased over the past 10 years. Transplant outcomes remain robust, with continuously improving graft survival rates for deceased donor, living donor, and donation after circulatory death livers. Numbers of new and prevalent pediatric candidates on the waiting list have decreased. Pediatric pretransplant mortality has decreased, most dramatically for candidates aged less than 1 year. The transplant rate has increased since 2002, and is highest in candidates aged less than 1 year. Graft survival continues to improve for pediatric recipients of deceased donor and living donor livers. Incidence of acute rejections increases with time after transplant. Posttransplant lymphoproliferative disorder remains an important concern in pediatric recipients., (© Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2013
- Full Text
- View/download PDF
43. OPTN/SRTR 2011 Annual Data Report: intestine.
- Author
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Smith JM, Skeans MA, Thompson B, Horslen SP, Edwards EB, Harper AM, Snyder JJ, Israni AK, and Kasiske BL
- Subjects
- Humans, Immunosuppressive Agents administration & dosage, Tissue and Organ Procurement, Waiting Lists, Intestines transplantation
- Abstract
Since 2006, the number of new intestinal transplant candidates listed each year has declined, likely reflecting increased medical and surgical treatment for intestinal failure. Historically, intestinal transplant occurred primarily in the pediatric population; in 2011, 41% of prevalent candidates on the waiting list were aged 18 years or older. The most common etiology of intestinal failure remains short-gut syndrome, which encompasses several diagnoses. The proportion of candidates with high medical urgency status decreased and time on the waiting list increased in 2011. The overall rate of transplant decreased from a peak of 92.7 transplants per 100 wait-list years in 2005 to 49.2 in 2011. The number of intestines recovered and transplanted per donor has decreased since 2007, possibly due to fewer listed patients. Almost 50% of deceased donor intestines were transplanted with another organ in 2011. Historically, the most common organ transplanted with the intestine was the liver, but in 2011 it was the pancreas. Graft survival has continued to improve over the past decade, and the number of recipients alive with a functioning intestinal graft has steadily increased since 1998. Hospitalization is common, occurring in 84.8% of recipients by 6 months posttransplant and in almost all by 4 years., (© Copyright 2012 The American Society of Transplantation and the American Society of Transplant Surgeons.)
- Published
- 2013
- Full Text
- View/download PDF
44. On Critchfield's proposal: student concerns and recommendations.
- Author
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Bayles MW, Boutain AR, Ackerlund Brandt JA, Call N, Dracobly JD, Greer BD, Gureghian DL, Harper AM, Merritt TA, Miller JR, Payne SW, and Morris EK
- Published
- 2012
- Full Text
- View/download PDF
45. Region 11 MELD Na exception prospective study.
- Author
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Fisher RA, Heuman DM, Harper AM, Behnke MK, Smith AD, Russo MW, Zacks S, McGillicuddy JW, Eason J, Porayko MK, Northup P, Marvin MR, Hundley J, and Nair S
- Subjects
- Adult, Aged, Carcinoma, Hepatocellular blood, Carcinoma, Hepatocellular surgery, End Stage Liver Disease blood, End Stage Liver Disease complications, Female, Humans, Hyponatremia blood, Hyponatremia etiology, Liver Cirrhosis blood, Liver Cirrhosis complications, Liver Neoplasms blood, Liver Neoplasms surgery, Male, Middle Aged, Prospective Studies, Resource Allocation standards, Retrospective Studies, Risk Factors, Sodium blood, Treatment Outcome, United States, Waiting Lists, End Stage Liver Disease surgery, Hyponatremia diagnosis, Liver Cirrhosis surgery, Liver Transplantation, Severity of Illness Index, Tissue and Organ Procurement standards
- Abstract
Introduction: Hyponatremia complicates cirrhosis and predicts short term mortality, including adverse outcomes before and after liver transplantation., Material and Methods: From April 1, 2008, through April 2, 2010, all adult candidates for primary liver transplantation with cirrhosis, listed in Region 11 with hyponatremia, were eligible for sodium (Na) exception., Results: Patients with serum sodium (SNa) less than 130 mg/dL, measured two weeks apart and within 30 days of Model for End Stage Liver Disease (MELD) exception request, were given preapproved Na exception. MELD Na was calculated [MELD + 1.59 (135-SNa/30 days)]. MELD Na was capped at 22, and subject to standard adult recertification schedule. On data end of follow-up, December 28, 2010, 15,285 potential U.S. liver recipients met the inclusion criteria of true MELD between 6 and 22. In Region 11, 1,198 of total eligible liver recipients were listed. Sixty-two (5.2%) patients were eligible for Na exception (MELD Na); 823 patients (68.7%) were listed with standard MELD (SMELD); and 313 patients (26.1%) received HCC MELD exception. Ninety percent of MELD Na patients and 97% of HCC MELD patients were transplanted at end of follow up, compared to 49% of Region 11 standard MELD and 40% of U.S.A. standard MELD (USA MELD) patients (p < 0.001); with comparable dropout rates (6.5, 1.6, 6.9, 9% respectively; p = 0.2). MELD Na, HCC MELD, Region 11 SMELD, and USA MELD post-transplant six-month actual patient survivals were similar (92.9, 92.8, 92.2, and 93.9 %, respectively)., Conclusion: The Region 11 MELD Na exception prospective trial improved hyponatremic cirrhotic patient access to transplant equitably, and without compromising transplant efficacy.
- Published
- 2012
46. Hepatic artery thrombosis after adult living donor liver transplantation: the effect of center volume.
- Author
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Salvalaggio PR, Modanlou KA, Edwards EB, Harper AM, and Abecassis MM
- Subjects
- Databases, Factual, Graft Survival, Humans, Living Donors, Retrospective Studies, Thrombosis pathology, Time Factors, Tissue and Organ Harvesting, Tissue and Organ Procurement, Treatment Outcome, Hepatic Artery pathology, Liver Transplantation methods, Thrombosis immunology
- Abstract
Background: To investigate whether center volume impacts the rate hepatic artery thrombosis (HAT) and patient survival after adult living donor liver transplantation (ALDLT)., Methods: Patients with HAT who were listed as Status 1 in the Organ Procurement Transplant Network database were included in the study. Recipients of ALDLT were compared to those who received a deceased donor liver transplant (DDLT)., Results: Recipients of ALDLT had a higher rate of HAT than recipients of DDLT. Centers that performed less than four adult ALDLT had a higher rate of HAT than other higher volume centers. "Novice" centers had a worse graft and patient survival than those with more experience in ALDLT. Recipients who had HAT experienced a worse patient survival than those who did not., Conclusions: Centers with higher volume have a lower rate of HAT and a better patient and graft survival in ALDLT. Clearer regulations and focus on overcoming the learning curve might be needed to increase the utilization of ALDLT.
- Published
- 2007
- Full Text
- View/download PDF
47. Liver transplantation for status 1: the consequences of good intentions.
- Author
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McDiarmid SV, Goodrich NP, Harper AM, and Merion RM
- Subjects
- Adult, Age Distribution, Child, Chronic Disease, Humans, Liver Diseases mortality, Liver Failure mortality, Registries, Risk Assessment, Liver Diseases physiopathology, Liver Diseases surgery, Liver Transplantation statistics & numerical data, Waiting Lists
- Abstract
Status 1 is the listing category reserved for patients awaiting liver transplantation who are at risk of imminent death. This high allocation priority was intended to benefit patients with acute liver failure and children with severe chronic liver failure. However, the status 1 criteria were not well defined. The aims of this study, which used the Organ Procurement and Transplantation Network/Scientific Registry of Transplant Recipients database for patients wait-listed between February 27, 2002, and September 30, 2003, were to determine the indication and numbers of children and adults at status 1 (including regional variations); examine death rates on the waiting list for children at vs. not at status 1; and examine time to death, transplant, or removal from the waiting list for both pediatric and adult status 1 candidates. During the study period, 40.3% of children and 6.1% of adults were transplanted at status 1. The indication was acute liver failure in 52.1% of adults and 31% of children. Among status 1 transplants, Regional Review Board exceptions were granted for 16.7% of children and 10.1% of adults. Death rates for children listed at status 1 by exception per patient-year at risk were substantially lower (0.51) than those of children with acute liver failure (4.06) or with chronic liver disease and Pediatric End-Stage Liver Disease score > or =25 (4.63). The percentage of adults who died while on the waiting list within 90 days of listing was more than twice that of children, whereas the percentages transplanted were similar. Patients listed and transplanted at status 1 were a heterogeneous population with an overrepresentation of children with varying degrees of chronic liver disease and other exceptions, and an associated wide variation in waiting list mortality. Recent changes in status 1 criteria provide stricter definitions, particularly for children, including the removal of the "by exception" category, with the intent that all candidates listed at status 1 share a similar mortality risk.
- Published
- 2007
- Full Text
- View/download PDF
48. Use of a pediatric end-stage liver disease score for deceased donor allocation: the United States experience.
- Author
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McDiarmid SV, Merion RM, Dykstra DM, and Harper AM
- Subjects
- Cadaver, Child, Chronic Disease, Humans, Liver Failure surgery, Tissue Donors, United States, Waiting Lists, Health Care Rationing, Liver Failure classification, Liver Transplantation, Severity of Illness Index, Tissue and Organ Procurement organization & administration
- Abstract
The Pediatric end-stage liver disease (PELD) score was developed as a measure of the severity of chronic liver disease that would predict mortality or children awaiting liver transplant. From multivariate analyses a model was derived that included five objective factors which together comprise the PELD score. The factors are growth failure, age less than 1 year, international normalized ratio (INR), serum albumin and total bilirubin.
- Published
- 2007
- Full Text
- View/download PDF
49. Reduced priority MELD score for hepatocellular carcinoma does not adversely impact candidate survival awaiting liver transplantation.
- Author
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Sharma P, Harper AM, Hernandez JL, Heffron T, Mulligan DC, Wiesner RH, and Balan V
- Subjects
- Cadaver, Carcinoma, Hepatocellular surgery, Female, Humans, Male, Middle Aged, Neoplasm Staging, Survival Analysis, Time Factors, Tissue Donors, United States, Carcinoma, Hepatocellular mortality, Carcinoma, Hepatocellular pathology, Liver Transplantation, Waiting Lists
- Abstract
The liver organ allocation policy of the United Network for Organ Sharing (UNOS) is based on the model for end-stage liver disease (MELD). The policy provides additional priority for candidates with hepatocellular carcinoma (HCC) who are awaiting deceased donor liver transplantation (DDLT). However, this priority was reduced on February 27, 2003 to a MELD of 20 for stage T1 and of 24 for stage T2 HCC. The aim of this study was to determine the impact of reduced priority on HCC candidate survival while on the waiting list. The UNOS database was reviewed for all HCC candidates listed after February 27, 2002, The HCC candidates were grouped into two time periods: MELD 1 (listed between February 27, 2002, and February 26, 2003) and MELD 2 (listed between February 27, 2003 and February 26, 2004). For the two time periods, the national DDLT incidence rates for HCC patients were 1.44 versus 1.53 DDLT per person-year (p = NS) and the waiting times were similar for the two periods (138.0 +/- 196.8 vs. 129.0 +/- 133.8 days; p = NS). Furthermore, the 3-, 6- and 12-month candidate, patient survival and dropout rates were also similar nationally. Regional differences in rates of DDLT for HCC were observed during both MELD periods. Consequently, the reduced MELD score for stage T1 and T2 HCC candidates awaiting DDLT has not had an impact nationally either on their survival on the waiting list or on their ability to obtain a liver transplant within a reasonable time frame. However, regional variations point to the need for reform in how organs are allocated for HCC at the regional level.
- Published
- 2006
- Full Text
- View/download PDF
50. Waiting list removal rates among patients with chronic and malignant liver diseases.
- Author
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Freeman RB, Edwards EB, and Harper AM
- Subjects
- Adolescent, Adult, Female, Humans, Liver Failure classification, Male, Middle Aged, Severity of Illness Index, Tissue and Organ Procurement organization & administration, United States, Carcinoma, Hepatocellular surgery, Health Care Rationing, Liver Diseases surgery, Liver Failure surgery, Liver Neoplasms surgery, Liver Transplantation statistics & numerical data, Waiting Lists
- Abstract
Equitable liver allocation should ensure that nonelective removal rates are fairly distributed among waiting candidates. We compared removal rates for adults entered with nonmalignant (NM) (N = 9379) and hepatocellular cancer (HCC) (N = 2052) diagnoses on the Organ Procurement and Transplantation Network (OPTN) list between April 30, 2003, and December 31, 2004. Unadjusted removal rates for NM vs. HCC diagnoses were 9.4% vs. 8.7%, 13.5% vs. 16.9% and 19.1% vs. 31.8% at 90, 180 and 365 days, respectively after listing. For NM candidates, model for end-stage liver disease (MELD) score (RR = 1.16), age (RR = 1.03) and metabolic disease diagnoses (RR = 1.66) had higher risks of removal; and PSC (RR = 0.62) and alcoholic cirrhosis (RR = 0.82) had lower risks of removal. For HCC candidates, MELD score at listing (RR = 1.09), AFP (RR = 1.02), maximum tumor size (RR = 1.16) and age at listing (RR = 1.02) had increased risks of removal. The equation 1 - 0.920 exp[0.09369 (MELD at listing - 12.48) + 0.00193 (AFP - 97.4) + 0.1505 (maximum tumor size - 2.59) defined the probability of dropout for HCC candidates within 90 days of listing. We conclude that factors associated with the risk of removal for HCC are different from NM candidates, although MELD score at listing remains the most predictive for both groups. Liver transplant candidates with HCC may be prioritized using a risk score analogous to the MELD score.
- Published
- 2006
- Full Text
- View/download PDF
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