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Purpose: Understanding potential bias due to rarity of the outcome is important when monitoring newly approved drugs and drugs with low availability to the general public. Although there is an increasing use of online surveys to investigate health outcomes, the limits of inference due to drug availability have not been studied. The goal of this study was to quantify the relationship between dispensing of prescription drugs and estimates of use in an online general population survey., Methods: An online repeated, cross-sectional survey from 2018 to 2020 was used to estimate the number of adults in the United States who used prescription drugs in the general population and compared to estimated number of prescriptions dispensed over an equivalent time period. Joinpoint regression was used to quantify thresholds. A sample of respondents was retested to estimate reliability statistics., Results: A model with a single threshold was the best fit, with the estimated threshold of 565 000 (95% CI: 9500-11 600 000) prescriptions dispensed per year. Above the threshold, there was a significant association between dispensing and estimates (p < 0.001); below the threshold, the relationship was not significant (p = 0.912). Above the threshold, responses were more reliable than random chance, and reliability steadily increased with increased dispensing., Conclusions: These results suggest the threshold demarcates two distinct pharmacoepidemiological paradigms when investigating drug use in general population surveys. Dispensing can be used as a guide to determine the epidemiological paradigm that is best suited., (© 2021 John Wiley & Sons Ltd.)

Background: Understanding prescription medication misuse is challenging due to lack of consistent measures of misuse behaviors and prevalence between countries. Tramadol is an atypical opioid with a dual mechanism, and has low drug liking compared to conventional opioids. We evaluate tramadol misuse compared to conventional opioids utilizing a harmonized validated national survey across four countries: Germany, Italy, Spain, and the United Kingdom (UK)., Methods: Data from the Survey of Non-Medical Use of Prescription Drugs (NMURx) Program online cross-sectional general population national surveys are analyzed from 2018 from four countries, with 45,000 total responses. Misuse and abuse of tramadol, codeine, morphine, and oxycodone are compared, and national prevalence estimates calculated via calibration weighting. Rates are calculated per population and per drug availability. Supplemental data are included from patients entering treatment centres and poison centre exposures., Results: In 2018, distribution, misuse, and abuse of four prescription opioids show similar patterns across four countries. In all countries, codeine is misused by the largest number of adults (estimated 861,181 in Italy to 4,676,680 in Spain in past 12 months). When adjusted for availability, tramadol is misused uncommonly with lowest or second lowest rates in all countries. Most abuse occurs by the oral route for all opioids, including tramadol with only 7.27 (Germany) to 54.92 (UK) cases per 100,000 units sold., Conclusions: In four countries, tramadol misuse and abuse are infrequent both in absolute number of cases and in comparison to conventional opioids. Even with availability of intravenous tramadol formulations, misuse by injection is rare., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background: In rapidly changing fields such as the study of drug use, the need for accurate and timely data is paramount to properly inform policy and intervention decisions. Trends in drug use can change rapidly by month, and using study designs with flexible modules could present advantages. Timely data from online panels can inform proactive interventions against emerging trends, leading to a faster public response. However, threats to validity from using online panels must be addressed to create accurate estimates., Objective: The objective of this study was to demonstrate a comprehensive methodological approach that optimizes a nonprobability, online opt-in sample to provide timely, accurate national estimates on prevalence of drug use., Methods: The Survey of Non-Medical Use of Prescription Drugs Program from the Researched Abuse, Diversion and Addiction Related Surveillance (RADARS) System is an online, cross-sectional survey on drug use in the United States, and several best practices were implemented. To optimize final estimates, two best practices were investigated in detail: exclusion of respondents showing careless or improbable responding patterns and calibration of weights. The approach in this work was to cumulatively implement each method, which improved key estimates during the third quarter 2018 survey launch. Cutoffs for five exclusion criteria were tested. Using a series of benchmarks, average relative bias and changes in bias were calculated for 33 different weighting variable combinations., Results: There were 148,274 invitations sent to panelists, with 40,021 who initiated the survey (26.99%). After eligibility assessment, 20.23% (29,998/148,274) of the completed questionnaires were available for analysis. A total of 0.52% (157/29,998) of respondents were excluded based on careless or improbable responses; however, these exclusions had larger impacts on lower volume drugs. Number of exclusions applied were negatively correlated to total dispensing volume by drug (Spearman ρ=-.88, P<.001). A weighting scheme including three demographic and two health characteristics reduced average relative bias by 31.2%. After weighting, estimates of drug use decreased, reflecting a weighted sample that had healthier benchmarks than the unweighted sample., Conclusions: Our study illustrates a new approach to using nonprobability online panels to achieve national prevalence estimates for drug abuse. We were able to overcome challenges with using nonprobability internet samples, including misclassification due to improbable responses. Final drug use and health estimates demonstrated concurrent validity to national probability-based drug use and health surveys. Inclusion of multiple best practices cumulatively improved the estimates generated. This method can bridge the information gap when there is a need for prompt, accurate national data., (©Joshua Curtis Black, Karilynn Rockhill, Alyssa Forber, Elise Amioka, K Patrick May, Colleen M Haynes, Nabarun Dasgupta, Richard C Dart. Originally published in the Journal of Medical Internet Research (http://www.jmir.org), 25.10.2019.)

Purpose of Study: The aim of the study is to describe the prevalence of illicit drug use in England and Wales using data from the UK Survey of Non-Medical Use of Prescription Drugs (NMURx) programme and to compare against the well-established Crime Survey England and Wales (CSEW). The rationale is that recreational and illicit drug use is common, but the prevalence is difficult to estimate with personal interviewing methods., Study Design: We compared two cross-sectional population surveys (NMURx, n=8903 and CSEW, n=20 685) with data regarding self-reported recreational drug use and demographics. NMURx is an online survey using non-probability sampling methodology with preset demographical quotas based on census data. CSEW surveys drug use via computer-assisted self-interviewing as part of a computer-assisted personal-interviewing crime survey., Results: Cannabis was the most frequently used drug regardless of demographics. Prevalence of drug use for specific substances was generally higher for males, younger ages and students. The relationship between income and drug misuse is less clear. Self-reported prevalence of drug use in the NMURx survey is consistently higher than CSEW (absolute difference 1%-3 % across substances and timescales) and persists after stratification for gender, age, student status and household income., Conclusions: The NMURx survey has a broad reach of participants, and a sampling scheme that achieves external validity, compared with general population demographics. NMURx's online format allows flexibility in items surveyed and in response to emerging trends. The self-reported drug use in the NMURx cohort is comparable, although slightly higher, than the CSEW estimates., Competing Interests: Competing interests: The RADARS System (KR, JCB, KPM, MDW, JLG) is supported by subscriptions from pharmaceutical manufacturers for surveillance, research and reporting services. RADARS System is the property of Denver Health and Hospital Authority, a political subdivision of the State of Colorado. Denver Health retains exclusive ownership of all data, databases and systems. Subscribers do not participate in data collection or analysis, nor do they have access to the raw data. PID is a member of the UK Advisory Council on the Misuse of Drugs, the European Monitoring Centre for Drugs and Drug Addiction Scientific Committee and the Glaxo Smith Kline Global Analgesics Advisory Panel. DMW is an Advisor to the UK Advisory Council on the Misuse of Drugs and the European Monitoring Centre for Drugs and Drug Addiction., (© Author(s) (or their employer(s)) 2018. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Wireless motility capsule (WMC) findings are incompletely defined in suspected gastroparesis. We aimed to characterize regional WMC transit and contractility in relation to scintigraphy, etiology, and symptoms in patients undergoing gastric emptying testing., Methods: A total of 209 patients with gastroparesis symptoms at NIDDK Gastroparesis Consortium centers underwent gastric scintigraphy and WMCs on separate days to measure regional transit and contractility. Validated questionnaires quantified symptoms., Key Results: Solid scintigraphy and liquid scintigraphy were delayed in 68.8% and 34.8% of patients; WMC gastric emptying times (GET) were delayed in 40.3% and showed 52.8% agreement with scintigraphy; 15.5% and 33.5% had delayed small bowel (SBTT) and colon transit (CTT) times. Transit was delayed in ≥2 regions in 23.3%. Rapid transit was rarely observed. Diabetics had slower GET but more rapid SBTT versus idiopathics (P ≤ .02). GET delays related to greater scintigraphic retention, slower SBTT, and fewer gastric contractions (P ≤ .04). Overall gastroparesis symptoms and nausea/vomiting, early satiety/fullness, bloating/distention, and upper abdominal pain subscores showed no relation to WMC transit. Upper and lower abdominal pain scores (P ≤ .03) were greater with increased colon contractions. Constipation correlated with slower CTT and higher colon contractions (P = .03). Diarrhea scores were higher with delayed SBTT and CTT (P ≤ .04)., Conclusions & Inferences: Wireless motility capsules define gastric emptying delays similar but not identical to scintigraphy that are more severe in diabetics and relate to reduced gastric contractility. Extragastric transit delays occur in >40% with suspected gastroparesis. Gastroparesis symptoms show little association with WMC profiles, although lower symptoms relate to small bowel or colon abnormalities., (© 2017 John Wiley & Sons Ltd.)

Purpose: Some human immunodeficiency virus (HIV)-infected individuals have evidence of optic nerve or retinal dysfunction that manifests as decreased contrast sensitivity, even with good best-corrected visual acuity (BCVA). This condition, termed HIV-related neuroretinal disorder (HIV-NRD), is a risk factor for vision impairment (BCVA <20/40), blindness (BCVA ≤20/200), and increased mortality. We investigated the effect of HIV-NRD on vision-specific quality of life (QOL)., Design: Cross-sectional analysis of data from a prospective, observational study., Participants: Individuals from the Longitudinal Study of the Ocular Complications of AIDS cohort who completed the National Eye Institute 25-item Visual Function Questionnaire (VFQ-25), had BCVA of 20/40 or better, and had no evidence of ocular opportunistic infection or cataract., Methods: We compared QOL by HIV-NRD status, adjusting for potential confounding variables, using multiple linear regression. Among those with HIV-NRD, we assessed the relationship between VFQ-25 and the logarithm of contrast sensitivity (logCS), using Spearman correlation. We defined a minimum clinically important difference (MCID) as 1 standard error of measurement from a well-characterized, historical population of individuals with a variety of ophthalmic disorders., Main Outcome Measures: Subscales and composite VFQ-25 scores (0 = worst, 100 = best)., Results: A total of 813 individuals met study criteria. Those with HIV-NRD (n = 39 [4.8%]) had a lower mean composite score than those without HIV-NRD (81 vs. 89; P = 0.0002) and lower mean scores in the following subscales: near activities (77 vs. 86; P = 0.004), distance activities (85 vs. 91; P = 0.01), social functioning (89 vs. 96; P = 0.0005), mental health (75 vs. 87; P = 0.0001), dependency (81 vs. 94; P < 0.0001), driving (75 vs. 85; P = 0.02), color vision (90 vs. 97; P < 0.0001), and peripheral vision (85 vs. 91; P = 0.0496). Score differences for each of these subscales met criteria for MCID. Among those with HIV-NRD, there was a positive correlation between logCS and composite score (r = 0.36; 95% confidence interval, 0.04-0.60)., Conclusions: HIV-NRD has a statistically significant and clinically meaningful association with decreased vision-specific QOL among people with AIDS and good BCVA., (Published by Elsevier Inc.)

Purpose: To determine the prevalence and incidence of epiretinal membranes (ERM) in eyes with inactive extramacular cytomegalovirus (CMV) retinitis in patients with acquired immune deficiency syndrome (AIDS)., Methods: A case-control report from a longitudinal multicenter observational study by the Studies of the Ocular Complications of AIDS (SOCA) Research Group. A total of 357 eyes of 270 patients with inactive CMV retinitis and 1084 eyes of 552 patients with no ocular opportunistic infection (OOI) were studied. Stereoscopic views of the posterior pole from fundus photographs were assessed at baseline and year 5 visits for the presence of macular ERM. Generalized estimating equations (GEE) logistic regression was used to compare the prevalence and 5-year incidence of ERM in eyes with and without CMV retinitis at enrollment. Crude and adjusted logistic regression was performed adjusting for possible confounders. Main outcome measures included the prevalence, incidence, estimated prevalence, and incidence odds ratios., Results: The prevalence of ERM at enrollment was 14.8% (53/357) in eyes with CMV retinitis versus 1.8% (19/1084) in eyes with no OOI. The incidence of ERM at 5 years was 18.6% (16/86) in eyes with CMV retinitis versus 2.4% (6/253) in eyes with no OOI. The crude odds ratio (OR) (95% confidence interval, CI) for prevalence was 9.8 (5.5-17.5) (P < 0.01). The crude OR (95% CI) for incidence was 9.4 (3.2-27.9) (P < 0.01)., Conclusions: A history of extramacular CMV retinitis is associated with increased prevalence and incidence of ERM formation compared to what is seen in eyes without ocular opportunistic infections in AIDS patients., (Copyright 2014 The Association for Research in Vision and Ophthalmology, Inc.)

Objective: We have recently shown that administration of long-term, low-dose methotrexate (MTX) causes severe osteopenia in female rats. This osteopenia is characterized both by decreased osteoblast function without a decrease in osteoblast numbers, and by increased bone resorption that is believed to represent a physiologic remodeling response by osteoclasts. The present study investigates the effects of varying doses of MTX on mouse bone cells in culture., Methods: Cells were obtained by sequential digestion of neonatal mouse calvariae, and cultured with fetal calf serum (10% for osteoblast-like cells and 2% for osteoclast-like cells). After 1 week, MTX was added to each culture in concentrations of 0.6 microM, 0.4 microM, 0.2 microM, 0.1 microM, 1 nM, and 0.5 nM. All experiments were done on 24 wells for each MTX concentration and for the controls. The effect on osteoblastic cells was assessed, at 7 days, by cell counts and by measurement of lysate alkaline phosphatase and supernatant osteocalcin levels, and, at 21 days, by analysis of the calcified matrix production, which was cultured with ascorbic acid and beta-glycerophosphate. For osteoclastic cells, cell count and lysate acid phosphatase levels were determined., Results: Levels of osteoblastic cells and lysate alkaline phosphatase were not changed by any of the concentrations of MTX. Matrix calcification and supernatant osteocalcin levels were diminished by MTX in a dose-responsive manner. Osteoclast-like cell numbers and acid phosphatase levels were not significantly affected by MTX., Conclusion: These results suggest that diminished mouse osteoblastic cell function occurs with very low mean concentrations of MTX, in a dose-responsive manner. The mechanism seems to be inability of the cell to synthesize and calcify matrix, possibly through defective osteocalcin production. Thus, low-dose MTX may have an important impact on bone density by slowing osteoblastic matrix production.

Objective: To ascertain the effects of low-dose methotrexate (MTX) on bone metabolism and histomorphometry in rats., Methods: Female Sprague-Dawley rats (6 months old, n = 42) were divided into the following 4 groups: intraperitoneal (IP) injections of MTX, with and without ovariectomy, and IP saline (controls), with and without ovariectomy. Injections were given for 16 weeks. The MTX dose was equivalent to a standard dose for rheumatoid arthritis in humans that would yield similar serum MTX levels (0.6 +/- 0.1 mumoles)., Results: Bone formation (assessed by serum alkaline phosphatase and osteocalcin levels and histomorphometry) was significantly lower in the MTX groups, and bone resorption (assessed by urinary hydroxyproline levels and histomorphometry) was increased in the MTX groups. Bone mass was significantly diminished in the MTX groups., Conclusion: Prolonged administration of low-dose MTX in rats causes significant osteopenia via suppression of osteoblast activity and stimulation of osteoclast recruitment, which results in increased bone resorption.

Purpose: Fibromyalgia is a common pain syndrome that is often associated with sleep disturbances. The most characteristic pattern noted on formal sleep study is alpha-wave intrusion on delta-wave sleep. This nonrestorative sleep pattern may be endogenous, or caused by any of a number of sleep disturbances. Our goal was to determine the frequency of sleep apnea and its relationship to a nonrestorative sleep pattern in our patients with fibromyalgia syndrome., Patients and Methods: All new fibromyalgia patients seen in the Rheumatology Clinic at Fitzsimons Army Medical Center were screened using history and physical examination for suspicion of sleep apnea. When this condition was suspected, the patients underwent formal polysomnography to delineate any sleep disturbance., Results: Four of 92 women, and 13 of 25 men with the new diagnosis of fibromyalgia syndrome underwent polysomnography. Of the women, 2.2% (2 of 92) had significant sleep apnea at formal evaluation; both were obese and had obstructive findings. In contrast, 44% (11 of 25) of the men had significant sleep apnea., Conclusions: Sleep apnea is not a significant cause of fibromyalgia symptoms in females. In male patients with fibromyalgia, sleep apnea was observed in a large percentage. Fibromyalgia may be a marker for occult sleep apnea in males.

Objective: Familial associations of the antiphospholipid antibody syndrome (APS) offer the opportunity to study genetic mechanisms of autoantibody production and disease, but are unusual. We identified a family, including identical twins and their mother, in which all members had systemic lupus erythematosus (SLE) and presented with different manifestations of the APS., Methods: Review of case histories and clinical laboratory results, antiphospholipid antibody (aPL) studies, complement C4 protein and gene analysis, and HLA typing of family members were performed., Results: Each of the 3 family members presented with a different clinical association of the APS. These various clinical presentations were closely temporally related. No particular aPL activity could be separated out that would account for the different manifestations, although the twin with thrombocytopenia and livedo reticularis had a strikingly high IgM anticardiolipin antibody level. C4A or C4B deficiencies could not be implicated in the autoimmune process. However, the mother and the twins shared the HLA haplotype that included the class II antigens DR4, DRw53, and DQw7, which has previously been associated with aPL production., Conclusion: This family study emphasizes the different clinical associations of aPL production in SLE. In addition to genetic influences that appear to include HLA class II antigens, the clinical presentations also suggest an environmental trigger.