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INTRODUCTION Home single-channel nasal pressure (HNP) may be an alternative to polysomnography (PSG) for obstructive sleep apnea (OSA) diagnosis, but no cost studies have yet been carried out. Automatic scoring is simpler but generally less effective than manual scoring. OBJECTIVES To determine the diagnostic efficacy and cost of both scorings (automatic and manual) compared with PSG, taking as a polysomnographic OSA diagnosis several apnea-hypopnea index (AHI) cutoff points. METHODS We included suspected OSA patients in a multicenter study. They were randomized to home and hospital protocols. We constructed receiver operating characteristic (ROC) curves for both scorings. Diagnostic efficacy was explored for several HNP AHI cutoff points, and costs were calculated for equally effective alternatives. RESULTS Of 787 randomized patients, 752 underwent HNP. Manual scoring produced better ROC curves than automatic for AHI < 15; similar curves were obtained for AHI ≥ 15. A valid HNP with manual scoring would determine the presence of OSA (or otherwise) in 90% of patients with a polysomnographic AHI ≥ 5 cutoff point, in 74% of patients with a polysomnographic AHI ≥ 10 cutoff point, and in 61% of patients with a polysomnographic AHI ≥ 15 cutoff point. In the same way, a valid HNP with automatic scoring would determine the presence of OSA (or otherwise) in 73% of patients with a polysomnographic AHI ≥ 5 cutoff point, in 64% of patients with a polysomnographic AHI ≥ 10 cutoff point, and in 57% of patients with a polysomnographic AHI ≥ 15 cutoff point. The costs of either HNP approaches were 40% to 70% lower than those of PSG at the same level of diagnostic efficacy. Manual HNP had the lowest cost for low polysomnographic AHI levels (≥ 5 and ≥ 10), and manual and automatic scorings had similar costs for higher polysomnographic cutoff points (AHI ≥ 15) of diagnosis. CONCLUSION Home single-channel nasal pressure (HNP) is a cheaper alternative than polysomnography for obstructive sleep apnea diagnosis. HNP with manual scoring seems to have better diagnostic accuracy and a lower cost than automatic scoring for patients with low apnea-hypopnea index (AHI) levels, although automatic scoring has similar diagnostic accuracy and cost as manual scoring for intermediate and high AHI levels. Therefore, automatic scoring can be appropriately used, although diagnostic efficacy could improve if we carried out manual scoring on patients with AHI < 15. CLINICAL TRIALS INFORMATION Clinicaltrials.gov identifier: NCT01347398.

Rationale Home respiratory polygraphy (HRP) may be a cost-effective alternative to polysomnography (PSG) for diagnosis and treatment election in patients with high clinical probability of obstructive sleep apnea (OSA), but there is conflicting evidence on its use for a wider spectrum of patients. Objectives To determine the efficacy and cost of OSA management (diagnosis and therapeutic decision making) using (1) PSG for all patients (PSG arm); (2) HRP for all patients (HRP arm); and (3) HRP for a subsample of patients with high clinical probability of being treated with continuous positive airway pressure (CPAP) and PSG for the remainder (elective HRP arm). Methods Multicentric study of 366 patients with intermediate-high clinical probability of OSA, randomly subjected to HRP and PSG. We explored the diagnostic and therapeutic decision agreements between the PSG and both HRP arms for several HRP cutoff points and calculated costs for equal diagnostic and/or therapeutic decision efficacy. Results For equal diagnostic and therapeutic decision efficacy, PSG arm costs were 18% higher than HRP arm costs and 20% higher than elective HRP arm costs. HRP arm costs tended to be lower than elective HRP arm costs, and both tended to be lower than PSG arm costs if patient costs were omitted. Conclusion Home respiratory polygraphy is a less costly alternative than polysomnography for the diagnosis and therapeutic decision making for patients with suspected obstructive sleep apnea. We found no advantage in cost terms, however, in using home respiratory polygraphy for all patients or home respiratory polygraphy for the most symptomatic patients and polysomnography for the rest.

RATIONALE Respiratory polygraphy is an accepted alternative to polysomnography (PSG) for sleep apnea/hypopnea syndrome (SAHS) diagnosis, although it underestimates the apnea-hypopnea index (AHI) because respiratory polygraphy cannot identify arousals. OBJECTIVES We performed a multicentric, randomized, blinded crossover study to determine the agreement between home respiratory polygraphy (HRP) and PSG, and between simultaneous respiratory polygraphy (respiratory polygraphy with PSG) (SimultRP) and PSG by means of 2 AHI scoring protocols with or without hyperventilation following flow reduction considered as a surrogate arousal. METHODS We included suspected SAHS patients from 8 hospitals. They were assigned to home and hospital protocols at random. We determined the agreement between respiratory polygraphy AHI and PSG AHI scorings using Bland and Altman plots and diagnostic agreement using receiver operating characteristic (ROC) curves. The agreement in therapeutic decisions (continuous positive airway pressure treatment or not) between HRP and PSG scorings was done with likelihood ratios and post-test probability calculations. RESULTS Of 366 randomized patients, 342 completed the protocol. AHI from HRP scorings (with and without surrogate arousal) had similar agreement with PSG. AHI from SimultRP with surrogate arousal scoring had better agreement with PSG than AHI from SimultRP without surrogate arousal. HRP with surrogate arousal scoring had slightly worse ROC curves than HRP without surrogate arousal, and the opposite was true for SimultRP scorings. HRP with surrogate arousal showed slightly better agreement with PSG in therapeutic decisions than for HRP without surrogate arousal. CONCLUSION Incorporating a surrogate arousal measure into HRP did not substantially increase its agreement with PSG when compared with the usual procedure (HRP without surrogate arousal).

Rationale: Obstructive sleep apnea (OSA) has been associated with increased cancer mortality, but whether it is also associated with cancer incidence is unknown.Objectives: To investigate whether OSA is associated with increased cancer incidence in a large clinical cohort.Methods: A multicenter, clinical cohort study including consecutive patients investigated for suspected OSA between 2003 and 2007 in seven Spanish teaching hospitals. Apnea-hypopnea index (AHI) and percent nighttime with oxygen saturation less than 90% (TSat90) were used as surrogates of OSA severity, both as continuous variables and categorized by tertiles. Cox proportional hazards regression analyses were used to calculate hazard ratio (HR) and 95% confidence interval (CI) for cancer incidence after adjusting for confounding variables.Measurements and Main Results: A total of 4,910 patients were analyzed (median follow-up, 4.5 yr; interquartile range, 3.4–5.2). Compared with the lower TSat90 category (

Automatic home respiratory polygraphy (HRP) scoring functions can potentially confirm the diagnosis of sleep apnoea-hypopnoea syndrome (SAHS) (obviating technician scoring) in a substantial number of patients. The result would have important management and cost implications. The aim of this study was to determine the diagnostic cost-effectiveness of a sequential HRP scoring protocol (automatic and then manual for residual cases) compared with manual HRP scoring, and with in-hospital polysomnography. We included suspected SAHS patients in a multicentre study and assigned them to home and hospital protocols at random. We constructed receiver operating characteristic (ROC) curves for manual and automatic scoring. Diagnostic agreement for several cut-off points was explored and costs for two equally effective alternatives were calculated. Of 366 randomised patients, 348 completed the protocol. Manual scoring produced better ROC curves than automatic scoring. There was no sensitive automatic or subsequent manual HRP apnoea-hypopnoea index (AHI) cut-off point. The specific cut-off points for automatic and subsequent manual HRP scorings (AHI >25 and >20, respectively) had a specificity of 93% for automatic and 94% for manual scorings. The costs of manual protocol were 9% higher than sequential HRP protocol; these were 69% and 64%, respectively, of the cost of the polysomnography. A sequential HRP scoring protocol is a cost-effective alternative to polysomnography, although with limited cost savings compared to HRP manual scoring.

Home respiratory polygraphy (HRP) is an alternative to polysomnography (PSG) for sleep apnea-hypopnea syndrome (SAHS) diagnosis. However, therapeutic decision-making is a different process than diagnosis.This study aimed to determine the agreement between HRP and in-hospital PSG for therapeutic decision-making in a large sample.Patients with an intermediate or high SAHS suspicion were included in a multicenter study (eight sleep centers) and assigned to home and hospital protocols in a random order. Therapeutic decisions (continuous positive airway pressure, no continuous positive airway pressure, or impossible decision) were made by an investigator in each center, based on using either HRP or PSG and a single set of auxiliary clinical variables. Patients and diagnostic methods (HRP and PSG) were assessed in random order using an electronic database. After a month the same therapeutic decision-making procedure was repeated with the same method.Of 366 randomized patients, 348 completed the protocol. The "impossible decision" case was not observed with either PSG or HRP. Therapeutic decisions using HRP had a sensitivity of 73%, a specificity of 77%, and an agreement level (sum of true positives and negatives) of 76%. Patients with higher HRP apnea-hypopnea index (AHI) scores (≥ 30; 41% of the total sample) had a sensitivity of 94%, a specificity of 44%, and the agreement level was 91%.The HRP-based therapeutic decision was adequate when AHI was high, but deficient in the large population of patients with mild to moderate AHI. Therefore, both selecting patients with a high suspicion and severity of SAHS and future prospective cost-effectiveness studies are necessary.

Resumen La piramide poblacion esta cambiando como consecuencia de la cada vez mayor longevidad de la poblacion por lo que se hace prioritario conocer en profundidad aquellas enfermedades que impactan con mayor frecuencia en edades avanzadas. El sindrome de apneas-hipopneas durante el sueno (SAHS) afecta al 15–20% de los individuos mayores de 65 anos. Sin embargo, y a pesar de esta elevada prevalencia y que en nuestro pais uno de 4 estudios de sueno se realiza en ancianos y que mas del 60% de estos seran tratados con CPAP, apenas existen estudios especificos para este grupo de edad sobre el diagnostico y manejo de esta enfermedad. Probablemente el incremento fisiologico con el paso del tiempo del numero de trastornos respiratorios durante el sueno sea el mayor obstaculo a la hora de definir, diagnosticar y tratar el SAHS en los ancianos. En cualquier caso y mientras llegan evidencias cientificas mas solidas tanto el Consenso Nacional de SAHS como las Normativas sobre el diagnostico y tratamiento del SAHS recomiendan que, dentro de limites logicos, la edad por si misma no sea un obstaculo para ofrecer a los ancianos un trato diagnostico y terapeutico semejante al ofrecido al resto de la poblacion.

Health-related quality-of-life (HRQL) tests used in sleep apnea-hypopnea syndrome (SAHS) are time-consuming, complicating their application in clinical practice. The objective was to examine the validity and responsiveness of a simple visual analogical well-being scale (VAWS) for the clinical use. The subjects proceed from a cohort of SAHS patients treated with CPAP for 12 weeks. We correlated the VAWS with other HRQL tests, related clinical and polysomnographic measures to concurrent and construct validities. Responsiveness by: (1) comparison of HRQL tests between before and after treatment and effect size. (2) Association of the change with treatment between VAWS with other HRQL tests and between VAWS with clinical parameters. At baseline, VAWS correlated with all HRQL tests but better with functional outcomes in sleep questionnaires (FOSQ) and European quality-of-life questionnaire (EuroQol) thermometer. VAWS and FOSQ correlated better with clinical variables than other HRQL tests. VAWS captures the magnitude change with treatment similarly to FOSQ but better than other HRQL tests. VAWS is a very simple test which measures HRQL in SAHS. It could be a useful tool in clinical practice, primarily for the responsiveness of treatment.

The population pyramid is changing due to the increasing longevity of the population, making it a priority to have better knowledge of those diseases that have an increasingly major impact in advanced age. Sleep apnea-hypopnea syndrome (SAHS) affects 15-20% of individuals over 65 years. However, despite this high prevalence and that one in four sleep studies are conducted on the elderly in this country and that more 60% of these were treated with CPAP, there are few specific studies in this age group on the diagnosis and management of this syndrome. The physiological increase of the number of sleep respiratory disorders with the passing of time may be the biggest obstacle when defining, diagnosing and treating SAHS in the elderly. In any case and while more solid scientific evidence is obtained, the National SAHS Consensus, as well as the Guidelines on the diagnosis and treatment of SAHS, recommend that, within logical limits, age itself should not be an obstacle to offering the elderly diagnostic help and treatment similar to that offered to the rest of the population.

Obstructive nonapnoeic event (ONE) scoring is shrouded in confusion. This is important in patients with mild disease, in whom precision is crucial. The aims of the present study were: 1) to identify ONEs using oesophageal pressure (OP) (OP-ONEs) and a noninvasive (NI) method (NI-ONEs); 2) to compare both methods of scoring; and 3) to determine the contribution of ONE definitions to clinical findings. Patients with suspected sleep apnoeas (respiratory disturbance index ≤10) during a first polysomnography were subjected to a second with an OP measurement. OP-ONEs and NI-ONEs were defined as an increase in OP or discernible reduction in the amplitude of thoracoabdominal bands with both desaturation and/or arousal. Bland–Altman analysis established agreement. Comparisons were made between OP-ONEs, NI-ONEs and clinical findings. In our sample (n = 90), the addition of an arousal to the NI-ONEs or OP-ONEs with only desaturation increased the number of NI-ONEs by 329 and 362%, respectively. NI-ONEs with arousal and/or desaturation detected 91% of OP-ONEs. The association with sleepiness depended on the incorporation of arousal into the definition of ONEs. In patients with mild disease, the addition of an arousal to ONEs, with only desaturation, markedly increased respiratory disturbance index, with probable therapeutic implications. Scoring respiratory events as apnoea and ONEs is easier and sufficiently accurate.

Sleep apnoea is a condition in which people stop breathing during sleep. A number of studies in general and worker populations have shown that the prevalence of an apnoea-hypopnoea index (AHI) > 10 is in the range of 20%. Subjects with an AHI > 10 that complain of excessive daytime somnolence, tiredness, asphyxic episodes during the night or non-refreshing sleep, among other symptoms, suffer from the sleep apnoea hypopnoea syndrome (SAHS). The prevalence of SAHS is around 4%. Owing to its high prevalence, clinical symptoms, probable secondary cardiovascular consequences and associated social problems, SAHS has a considerable impact on health, management of which is worth considering. Despite the fact that SAHS treatment has been challenged recent studies conclude that nasal continuous positive airway pressure (nCPAP) is undoubtedly effective in clearly symptomatic patients. Its use in clinical practice is adequately supported in the treatment of moderate to severe SAHS. Further studies are needed in order to define the lower range of symptoms to be treated. One of the most important problems encountered in this area results from the combination of two situations. On the one hand, different epidemiological studies have demonstrated that an AHI > 10 without symptoms is present in around 15% of the general population. On the other hand, several studies suggest that having a high AHI, even without secondary symptoms, gives rise to some undesirable effects such as traffic accidents and cardiovascular consequences. In this context, comprehensive epidemiological studies are therefore warranted to define the role of nCPAP treatment especially in those subjects with a high AHI but with few or no symptoms. (C) 2002 Published by Elsevier Science Ltd.

The association between obstructive sleep apnea (OSA) and cancer mortality has scarcely been studied. The objective of this study was to investigate whether OSA is associated with increased cancer mortality in a large cohort of patients with OSA suspicion.This was a multicenter study in consecutive patients investigated for suspected OSA. OSA severity was measured by the apnea-hypopnea index (AHI) and the hypoxemia index (% night-time spent with oxygen saturation90%, TSat90). The association between OSA severity and cancer mortality was assessed using Cox's proportional regression analyses after adjusting for relevant confounders.In all, 5427 patients with median follow-up of 4.5 years were included. Of these, 527 (9.7%) were diagnosed with cancer. Log-transformed TSat90 was independently associated with increased cancer mortality in the entire cohort (hazard ratio [HR], 1.21; 95% confidence interval [CI], 1.03-1.42), as well as in the group of patients with cancer (HR, 1.19; 95% CI, 1.02-1.41). The closest association was shown in patients65years in both the AHI (continuous log-transformed AHI: HR, 1.87; 95% CI, 1.1-3.2; upper vs lower AHI tertile: HR, 3.98; 95% CI, 1.14-3.64) and the TSat90 (continuous log-transformed TSat90: HR, 1.73; 95% CI, 1.23-2.4; upper vs. lower TSat90 tertile: HR, 14.4; 95% CI, 1.85-111.6).OSA severity was associated with increased cancer mortality, particularly in patients aged65 years.

In patients with acute exacerbations of asthma, the intravenous administration of bronchodilators, such as salbutamol, entails the potential risk of worsening pulmonary gas exchange, despite an amelioration of airflow obstruction. The present study was designed to investigate the effect of intravenous aminophylline on pulmonary gas exchange in patients hospitalized with a severe exacerbation of asthma. We studied 12 patients (aged 41 +/- 13 yrs) admitted to the hospital because of an exacerbation of asthma. The study was of a randomized, double-blind, placebo-controlled design. Six patients were treated with intravenous aminophylline and six received placebo, in addition to standard treatment with inhaled salbutamol and intravenous corticosteroids. Forced spirometry, respiratory gas exchange, ventilation-perfusion relationships assessed with the multiple inert gas elimination technique, and systemic haemodynamics were measured at baseline and 60 min after treatment started. In the aminophylline-treated group, mean theophylline plasma levels increased to 15.2 +/- 3.6 micrograms.ml-1, forced expiratory volume (FEV1) increased by 17 +/- 12%, and forced vital capacity (FVC) by 16 +/- 10%. The mean changes in FEV1 and FVC in the aminophylline-treated group were significantly higher than in the placebo-treated group. Likewise, minute ventilation increased by 23 +/- 14% and arterial carbon dioxide tension (PaCO2) decreased by 0.4 +/- 0.3 kPa (3 +/- 2 mmHg) during aminophylline infusion. No significant changes in arterial oxygen tension (PaO2) or in ventilation-perfusion distributions were shown in aminophylline-treated patients.(ABSTRACT TRUNCATED AT 250 WORDS)

The views presented in this article are the fruit of reflections and discussion with my colleagues at Valladolid and with the members of the Sleep Apnea Hypopnea Syndrome Group of the CIBERES (Spain). We have assembled the article in three sections. In the first one we provide a mechanistic description of obstructive sleep apnea (OSA) and all of its components, including the repetitive episodes of upper airways (UA) obstruction and accompanying hypoxic hypoxia, the respiratory efforts to fight and overcome the obstruction, and the sleep fragmentation due to the hypoxia-triggered arousal reactions, all events occurring during sleep hours with frequencies that might reach up40-50 episodes/sleep hour. When OSA is accompanied by some of the elements of a big cohort of associated pathologies (vascular, metabolic, and neuropsychiatric) it conforms the obstructive sleep apnea syndrome (OSAS). The high frequency of OSAS in adults (35 years old) and the costs in every regard of the treatment makes the syndrome a primary importance socio-sanitary problem. In the second section, we describe the experimental models of OSAS, basically the episodic repetitive hypoxic model described by Fletcher and coworkers in 1992, today named in short intermittent hypoxia (IH). From these lines, we want to call for some kind of consensus among researchers to lessen the dispersion of IH protocols. Finally, in the last section we intend to share our optimism with all ISAC members. The optimism is based on the recognition that carotid body (CB) chemoreceptors are critical elements of one of the main pathophysiologic loops in the genesis of OSAS. Therefore, we believe that all of us, as ISAC members, are well qualified to contribute in multidisciplinary research teams with well defined translational interests.

The views presented in this article are the fruit of reflections and discussion with my colleagues at Valladolid and with the members of the Sleep Apnea Hypopnea Syndrome Group of the CIBERES (Spain). We have assembled the article in three sections. In the first one we provide a mechanistic description of obstructive sleep apnea (OSA) and all of its components, including the repetitive episodes of upper airways (UA) obstruction and accompanying hypoxic hypoxia, the respiratory efforts to fight and overcome the obstruction, and the sleep fragmentation due to the hypoxia-triggered arousal reactions, all events occurring during sleep hours with frequencies that might reach up >40–50 episodes/sleep hour. When OSA is accompanied by some of the elements of a big cohort of associated pathologies (vascular, metabolic, and neuropsychiatric) it conforms the obstructive sleep apnea syndrome (OSAS). The high frequency of OSAS in adults (>35 years old) and the costs in every regard of the treatment makes the syndrome a primary importance socio-sanitary problem. In the second section, we describe the experimental models of OSAS, basically the episodic repetitive hypoxic model described by Fletcher and coworkers in 1992, today named in short intermittent hypoxia (IH). From these lines, we want to call for some kind of consensus among researchers to lessen the dispersion of IH protocols. Finally, in the last section we intend to share our optimism with all ISAC members. The optimism is based on the recognition that carotid body (CB) chemoreceptors are critical elements of one of the main pathophysiologic loops in the genesis of OSAS. Therefore, we believe that all of us, as ISAC members, are well qualified to contribute in multidisciplinary research teams with well defined translational interests., Supported by the MICINN grant (BFU2007-61848) and Accion Integrada PT2009-0172 and ICiii-CIBERES CB06/06/0050.

Home respiratory polygraphy (HRP) may be a cost-effective alternative to polysomnography for the diagnosis of sleep apnoea-hypopnoea syndrome (SAHS), but stronger evidence is needed. Normally, patients transport HRP equipment from the hospital to home and back, which may create difficulties for some patients.To determine both the diagnostic efficacy and cost of HRP (with and without a transportation service moving the device and telematic transmission of data) in a large sample compared with in-hospital polysomnography.Patients suspected of having SAHS were included in a multicentre study (eight hospitals). They were assigned to home and hospital protocols in random order. Receiver operating characteristic curves were constructed for manual respiratory polygraphy scoring protocol and different polysomnographic cut-off points. Diagnostic efficacies for several polysomnographic cut-off points were explored and costs for two equally effective alternatives were calculated.Of 366 randomised patients, 348 completed the protocol. The best receiver operating characteristic curve was obtained with a polysomnographic cut-off of the apnoea-hypopnoea index (AHI)≥5. The sensitive HRP AHI cut-off point (5) had a sensitivity of 96%, a specificity of 57% and a negative likelihood ratio (LR) of 0.07; the specific cut-off (10) had a sensitivity of 87%, a specificity of 86% and a positive LR of 6.25. The cost of HRP was half that of polysomnography. Telematic transmission costs were similar if the patients' costs were taken in to account.HRP is an alternative to polysomnography in patients with suspected SAHS. Telematic procedures may help patients with limited mobility and those who live a long way from the sleep centre.

Obstructive Sleep Apnoea (OSA) seems to worsen metabolism. This effect has not evaluated in morbid obesity (MO). We hypothesized that the metabolic profile is more impaired in MO patients with OSA than in those without and investigated whether any specific metabolic dysfunction is related to OSA in MO. A prospective multi-centre cross-sectional study was conducted in consecutive subjects before bariatric surgery. OSA was defined as apnoea-hypopnoea index (AHI)≥15 by overnight polysomnography (PSG). Anthropometrical, blood pressure (BP) and fasting blood measurements were obtained the morning after. Metabolic Syndrome (MetS) was defined according to NCEP ATPIII modified criteria. 159 patients were studied: 72% female, 72% OSA. MetS prevalence was 70% in OSA vs 36% in non-OSA (p

Objective: To assess the effect of continuous positive airway pressure (CPAP) on 24 hour ambulatory blood pressure monitoring values in a large number of patients with untreated systemic hypertension of new onset and obstructive sleep apnoea. Design: Multicentre, double blind, randomised, placebo controlled trial. Setting: Eleven general hospitals in Spain between 2004 and 2007. Participants: 340 patients recently diagnosed as having systemic hypertension by a general practitioner (systolic blood pressure ≥140 mm Hg, diastolic blood pressure ≥90 mm Hg, or both) and an apnoea-hypopnoea index per hour of sleep of >15 events/hour. Intervention: Patients were assigned to CPAP (n=169) or sham CPAP (n=171) for three months. Main outcome measurements Net changes in the different 24 hour ambulatory blood pressure monitoring values from baseline to three months of optimal or sham CPAP. Results: 277 (81%) of the 340 patients randomised were men; the patients had a mean age of 52.4 (SD 10.5) years, a body mass index of 31.9 (5.7), an Epworth sleepiness scale score of 10.1 (4.3), an apnoea-hypopnoea index of 43.5 (24.5). No differences between groups were seen at baseline. Compared with placebo and analysed by intention to treat, the mean 24 hour ambulatory blood pressure of the CPAP group decreased by 1.5 (95% confidence interval: 0.4 to 2.7) mm Hg (P=0.01). The mean 24 hour ambulatory blood pressure monitoring measures decreased by 2.1 mm Hg (0.4 to 3.7) mm Hg (P=0.01) for systolic pressure and 1.3 (0.2 to 2.3) mm Hg (P=0.02) for diastolic blood pressure. Mean nocturnal blood pressure decreased by 2.1 (0.5 to 3.6) mm Hg (P=0.01). Conclusions: CPAP produced a statistically significant reduction in blood pressure in patients with systemic hypertension and obstructive sleep apnoea. This reduction is small and did not achieve the 3 mm Hg drop in mean 24 hour ambulatory blood pressure that the trial was powered to detect. Consequently, these results may have uncertain clinical relevance. However, taking into account the prevalence of hypertension and the likelihood of comorbidities, the decrease in blood pressure, although minimal, may be beneficial. Trial registration: Clinical trials NCT00202527. The study was sponsored by the Spanish Ministry of Health (PI041110), the Basque Government’s Department of Health (20031103), and the Spanish Respiratory Society (SEPAR 2005). The sponsors had no role in the design and conduct of the study; in the collection, analysis, and interpretation of the data; or in the preparation, review, and approval of the manuscript. The opinions, results, and conclusions are those of the authors.

Study objectives Taking an afternoon nap (siesta) is a common habit. A number of studies have shown an increased cardiovascular mortality in habitual nappers. Afternoon nappers have anthropometric characteristics similar to those of patients with sleep apnea. Nappers appear to suffer from more sleep apnea, which could contribute to cardiovascular disorders. Our aim was therefore to determine the association between sleep apnea and napping, as well as to analyze the relationship of sleep apnea and napping with hypertension. Design Case-control study. Setting Residents in the town of Caceres (Spain) with a population of 100,000 inhabitants. Participants Four hundred five individuals were initially selected (186 nappers and 219 nonnappers). Interventions Telephone interviews were conducted to contact habitual nappers and nonnappers. Out of the total population selected, 90 nappers and 88 nonnappers completed the study protocol (personal interview and polysomnography). Measurements and results The nappers had a higher frequency of sleep apnea at the 3 cutoff points studied (apnea and hypopnea index > or = 5, > or = 10, > or = 15). The adjusted odds ratio was between 2.8 (confidence interval, 1.3-5.8) and 5.5 (confidence interval, 2.3-13). Napping was associated with hypertension in the univariate analysis (odds ratio: 2.1; confidence interval, 1.1-4), but this association disappeared once sleep apnea was included as a covariate in the multivariate modeling (odds ratio dropped to 1.1). Conclusions Our findings suggest that napping could be regarded as a marker of sleep apnea, which could account for the cardiovascular diseases observed in nappers. Given that napping is common and that sleep apnea is treatable, more attention should be focused on this population.

Standard practice for continuous positive airway pressure (CPAP) treatment in sleep apnea and hypopnea syndrome (SAHS) requires pressure titration during attended laboratory polysomnography. However, polysomnographic titration is expensive and time-consuming. The aim of this study was to ascertain, in a large sample of CPAP-naive patients, whether CPAP titration performed by an unattended domiciliary autoadjusted CPAP device or with a predicted formula was as effective as CPAP titration performed by full polysomnography. The main outcomes were the apnea-hypopnea index and the subjective daytime sleepiness. We included 360 patients with SAHS requiring CPAP treatment. Patients were randomly allocated into three groups: standard, autoadjusted, and predicted formula titration with domiciliary adjustment. The follow-up period was 12 weeks. With CPAP treatment, the improvement in subjective sleepiness and apnea-hypopnea index was very similar in the three groups. There were no differences in the objective compliance of CPAP treatment and in the dropout rate of the three groups at the end of the follow-up. Autoadjusted titration at home and predicted formula titration with domiciliary adjustment can replace standard titration. These procedures could lead to considerable savings in cost and to significant reductions in the waiting list.

⇓The sleep apnoea syndrome represents something of a paradox in clinical medicine. On the one hand, this disorder has been recognised only in recent decades, and is still regarded as a niche interest by many clinicians, particularly those from clinical disciplines other than respiratory medicine, neurology and otolaryngology. On the other hand, the syndrome is now recognised as being very common and current epidemiological data indicate that sleep apnoea syndrome is second only to asthma in the prevalence league table of chronic respiratory disorders 1. Furthermore, there is increasing evidence that sleep apnoea syndrome is associated with a considerable number of adverse sequelae, both behavioural and physical. Behavioural consequences include daytime sleepiness, impaired concentration and neuropsychological dysfunction, whereas physical consequences include cardiovascular disorders, particularly hypertension. In 1997, the European Respiratory Society (ERS) established a Task Force to examine the Public Health and Medicolegal Implications of the Sleep Apnoea Syndrome with particular reference to the impact of sleepiness on patient and public safety. The following report represents the outcome of several meetings and discussions of the Task Force membership and also includes a review of current European Regulations concerning driver licensing prepared by one of the members (J. Krieger). Obstructive sleep apnoea syndrome (OSAS) is a condition characterised by repetitive obstruction of the upper airway, often resulting in oxygen desaturation and arousals from sleep. The principal daytime manifestation is excessive sleepiness but other symptoms such as unrefreshing sleep, poor concentration and fatigue are commonly reported. Early definitions of the syndrome were based on an apnoea frequency without reference to symptoms 2. However, as epidemiological data from many studies made it clear that apnoeas during sleep are very common in the general population, the definition of a clinical syndrome was revised to include certain symptoms, particularly daytime sleepiness. Hypopnoeas …

Introduction: Home single-channel nasal pressure (HNP) may be an alternative to polysomnography (PSG) for obstructive sleep apnea (OSA) diagnosis, but no cost studies have yet been carried out. Automatic scoring is simpler but generally less effective than manual scoring. Objectives: To determine the diagnostic efficacy and cost of both scorings (automatic and manual) compared with PSG, taking as a polysomnographic OSA diagnosis several apnea-hypopnea index (AHI) cutoff points. Methods: We included suspected OSA patients in a multicenter study. They were randomized to home and hospital protocols. We constructed receiver operating characteristic (ROC) curves for both scorings. Diagnostic efficacy was explored for several HNP AHI cutoff points, and costs were calculated for equally effective alternatives. Results: Of 787 randomized patients, 752 underwent HNP. Manual scoring produced better ROC curves than automatic for AHI < 15; similar curves were obtained for AHI >= 15. A valid HNP with manual scoring would determine the presence of OSA (or otherwise) in 90% of patients with a polysomnographic AHI >= 5 cutoff point, in 74% of patients with a polysomnographic AHI >= 10 cutoff point, and in 61% of patients with a polysomnographic AHI >= 15 cutoff point. In the same way, a valid HNP with automatic scoring would determine the presence of OSA (or otherwise) in 73% of patients with a polysomnographic AHI >= 5 cutoff point, in 64% of patients with a polysomnographic AHI >= 10 cutoff point, and in 57% of patients with a polysomnographic AHI >= 15 cutoff point. The costs of either HNP approaches were 40% to 70% lower than those of PSG at the same level of diagnostic efficacy. Manual HNP had the lowest cost for low polysomnographic AHI levels (>= 5 and >= 10), and manual and automatic scorings had similar costs for higher polysomnographic cutoff points (AHI >= 15) of diagnosis. Conclusion: Home single-channel nasal pressure (HNP) is a cheaper alternative than polysomnography for obstructive sleep apnea diagnosis. HNP with manual scoring seems to have better diagnostic accuracy and a lower cost than automatic scoring for patients with low apnea-hypopnea index (AHI) levels, although automatic scoring has similar diagnostic accuracy and cost as manual scoring for intermediate and high AHI levels. Therefore, automatic scoring can be appropriately used, although diagnostic efficacy could improve if we carried out manual scoring on patients with AHI < 15.

BACKGROUND: Minor differences in technique may account for the wide range of published normal values of maximum expiratory and inspiratory pressures. The effects of holding the lips while the subject performed a maximal expiratory pressure manoeuvre were investigated in this study. METHODS: Maximum static expiratory pressures (PEmax) obtained with a cylindrical tube by means of lip compression by the subject and technician aided compression were compared in 20 men (mean age 27 years) and 20 women (mean age 28 years). RESULTS: Technician aided lip compression was associated with higher maximum expiratory pressure than compression by the subject in both men (195 v 110 cm H2O) and women (134 v 80 cm H2O). CONCLUSION: Compression of the lips and corners of the mouth should be performed by a trained technician for maximum expiratory pressure measurements when a cylindrical mouthpiece is used.

Seven patients suffering from amiodarone-induced pneumonitis were followed after diagnosis over a period of 16 +/- 6 months. All of them showed clinical, radiographic and functional manifestations of interstitial lung disease. Bronchoalveolar lavage was performed on 6 of them and disclosed lymphocytosis in 2 cases (associated to eosinophilia in 1 of them), neutrophilia in 1 and normal differential count in 2. In 1 case there were abundant hemosiderin-laden macrophages. In addition, all patients evidenced an increased 67Ga lung scan uptake. After discontinuation of amiodarone therapy (with or without corticosteroid therapy), 67Ga lung uptake normalized in 3 cases, but remained increased in 3. Bronchoalveolar lavage was repeated only in 2 cases, showing disappearance of lymphocytosis in one and abundant hemosiderin-laden macrophages in the other. Our results suggest that (1) hemosiderin-laden macrophages can be found in bronchoalveolar lavage in patients with amiodarone-induced pneumonitis, probably related to subclinical chronic left-sided heart failure; (2) 67Ga lung scan appears to be a sensitive marker of amiodarone pneumonitis, although it can remain abnormal after pulmonary clinical, radiographic and functional normalization.

The outcome of 49 asthmatics (20 men and 29 women) who had suffered a severe exacerbation of asthma requiring mechanical ventilation was investigated in a follow-up study ranging from 23 weeks to 10 years. Over this time, there were 6 fatalities, all female chronic asthmatics requiring treatment with bronchodilators, beclometha-sone, and short courses of oral steroids. Three died at home as a consequence of a sudden attack. Another patient developed a cardiorespiratory arrest immediately after having received a sedative. In the remaining two cases, death occurred within hours or days of progressive deterioration. Four of the six women had required psychiatric treatment for an anxiety-depression syndrome. These findings support previous studies suggesting that psychological disturbances may be predisposing factors to death in bronchial asthma.

Patterns of a/ distribution and their relationship to spirometric indices were studied in 10 patients with acute severe asthma requiring hospitalization (7 women and 3 men 41.0 ± 5.6 yr of age, mean ± SEM) on admission and during subsequent recovery. On admission, all patients received the standard therapeutic regimen for our hospital. Spirometry and essentially noninvasive multiple inert gas elimination measurements were obtained serially, approximately once every day, whereas conventional arterial blood gases were determined every 3 days. On admission, all patients showed severe air-flow obstruction (FEV1/FVC% = 34.1 ± 4.3%) and moderate to severe hypoxemia without CO2 retention (PaO2 = 50.5 ± 2.6 mm Hg; PaCO2 = 37.1 ± 2.4 mm Hg; AaPO2 = 53.7 ± 3.0 mm Hg). Nine of the 10 patients showed bimodal blood flow distributions (dispersion of blood flow distribution, log SD Q = 1.34 ± 0.11; normal range, 0.3 to 0.6) with only small amounts of shunt (1.09 ± 0.8%). However, no significant interindividual correlati...

Resumen Se analiza la respuesta a un tratamiento estandar realizado con teofilina, salbutamol y corti coides, en un grupo de asmaticos ingresados por agudizacion grave de su enfermedad (AGA gra do II). En todos ellos se observo una mejoria clinica y/o funcional, pudiendo ser dados de alta al nove no dia del tratamiento. Se observo un periodo libre entre tres y cinco dias hasta que la mejoria comen zaba a ser evidente. Segun las valoraciones de PEF (Peak Expiratory Flow), se obtuvieron tres modelos de recuperacion: uno rapido hacia la normalidad (A), otro lento, tambien hacia la normalidad (B), y un tercero de recuperacion incompleta (C). Estos modelos parecen guardar relacion con la edad, siendo los del grupo A significativamente menores que los del B y C. Las pruebas funcionales efectuadas antes del al ta, demostraron la presencia de un patron obstruc tivo de mediana intensidad en los pacientes perte necientes al modelo C. Este diferente comportamiento debera ser consi derado siempre que se realicen ensayos terapeuti cos en enfermos asmaticos.

Se presenta el caso de una paciente afecta de neumonia eosinofila cronica (NEC) que, tras iniciar tratamiento corticoideo, presento una evolucion clinico radiologica correcta. Tras resaltar la rareza de esta entidad nosologica, se subraya el interes diagnostico que comporta el lavado broncoalveolar en la NEC.

Se midieron las presiones inspiratorias maximas estaticas (pico y meseta) —PIM— en diez sujetos normales. Las medidas fueron repetidas 6 veces a lo largo de 6 semanas consecutivas. Se observo un aumento estadisticamente significativo a partir de la cuarta determinacion en la presion pico y de la sexta en la presion meseta. La presion pico y la presion meseta se comportaron siempre de un modo similar siendo su diferencia practicamente constante a lo largo de las seis semanas. En consecuencia, creemos que para una interpretacion correcta de la PIM debe de tenerse en cuenta el efecto aprendizaje. Con fines practicos la presion pico puede ser usada para medir la funcion muscular al igual que la presion meseta.

The prevalence of spontaneous pneumothorax was studied in 82 patients with cryptogenic fibrosing alveolitis. In 46 patients the disease affected only the lung ('lone' fibrosing alveolitis); in the remaining 36 patients the interstitial lung disease was associated with several systemic diseases ('associated' fibrosing alveolitis). 3 patients with the 'lone' form had a spontaneous pneumothorax. This figure represents a prevalence of 3.6%. We did not observe this complication in any patient with the associated form. Suction drainage was ineffective in the 3 patients. One of them died as a consequence of pleural infection. In the other 2 subjects thoracotomy, resection of blebs and pleurectomy were required.

To determine the number of maximal mouth pressure manoeuvres needed to obtain a reproducible value of maximal inspiratory mouth pressure (MIP), we studied 44 patients with chronic airflow obstruction, with a mean (SD) % predicted FEV1 value of 53.9 (25), who were clinically stable. Maximal inspiratory mouth pressure was determined with an anaeroid manometer during maximal inspiratory efforts in a quasi static condition at residual volume. All patients performed 20 consecutive maximal inspiratory mouth manoeuvres, each one separated by 30-40 seconds. The mean (SD) values of MIP varied from 71.5 (25.5) cm H2O at the first measurement to 80.1 (27) cm H2O at the last measurement. Maximal values of MIP were usually achieved after nine determinations. It is concluded that to obtain a reproducible MIP value in patients with chronic airflow obstruction who are untrained and unexperienced in such manoeuvres a minimum of nine technically acceptable maximal mouth pressure manoeuvres should be performed.

Asthmatics who sometimes experience respiratory arrest during an exacerbation are a particular concern. To date no adequate explanation exists for this phenomenon. Impaired perception of resistive loads is considered a factor in the development of hypercapnic respiratory failure, especially during exacerbation in patients with chronic obstructive pulmonary disease. We analyzed the perception of resistive loads in 10 asthmatics who had suffered two or more respiratory arrests during an acute exacerbation. A group of eight asthmatics (same mean age and basal bronchial obstruction) who had never developed respiratory arrest or acidosis during their exacerbations was also studied. No statistically significant differences were found between the two groups in the perception of resistive loads. This negative result seems to exclude a deficiency in the ability to detect resistive loads as a cause of respiratory arrest in asthmatic patients.

Sleep apnea hypopnea syndrome (SAHS) is an entity that occurs frequently in the population and produces an elevated morbidity and mortality, especially at an apnea index greater than 20 events per hour. To our knowledge there are only a few studies available addressing the general health status of sleep apnea hypopnea patients. Such information may be useful for both clinical management and better understanding of the physiopathological mechanisms of the disease, particularly with the consideration that not infrequently the physiological disturbances found in such patients do not always agree with their own health perception. Therefore, the aim of the present study was to assess the general health status and the degree of daytime somnolence, as a major symptom in SAHS patients, and relate them to the number of respiratory events per hour. Measurements of general health status and the degree of daytime somnolence were assessed in 103 consecutive patients 50.4 +/- 12 years old [mean +/- standard deviation (SD)] with an apnea/hypopnea index (AHI) of 38 +/- 27 events per hour. Forty nonsnoring healthy subjects were used as the control group. During the afternoon preceding the full polysomnography, a medical history was taken; basic anthropometric data and the presence of other diseases were recorded. The Nottingham Health Profile (NHP) questionnaire and a questionnaire assessing the degree of daytime somnolence were administered to the patients. No significant differences were found in the general health status and the degree of daytime hypersomnolence when patients were divided into three groups according to the severity of the respiratory events during the night, but there were significant differences between SAHS patients and control subjects. It was concluded that in spite of the fact that SAHS patients showed a deterioration of general health status parameters in comparison with healthy subjects, these parameters do not correlate with the physiological disturbances of SAHS, expressed as the number of respiratory events per hour.

We describe a case of a lingual tonsillar metastasis as the first manifestation of a bronchial adenocarcinoma. Tonsillar metastases infrequently become manifest before the diagnosis of the primary neoplasm. A review of the literature disclosed 89 cases of carcinoma metastasizing to the palatine tonsil, but no one has reported the involvement of the lingual tonsil. Our patient is the first described case of bronchogenic carcinoma with this unusual form of presentation and furthermore is also the first carcinoma metastasizing to the lingual tonsil.

Although the mechanism of aspirin-induced asthma and rhinitis is unknown, it has been suggested that adverse nasal and bronchial reactions are caused by an increased production of lipoxygenase products. In examining this hypothesis we have measured the release of peptide leukotrienes (PeptLTs), 15-HETE, and prostaglandins in nasal fluids obtained by nasal lavages after instillation of acetylsalycilic acid (ASA) and placebo (saline). Ten ASA-sensitive asthmatics, 10 ASA-insensitive asthmatics, and seven healthy subjects were challenged in a double-blind study with normal saline and 12 mg of ASA. Twelve mg were administered based on the results of a previous study that showed that this dose caused minor to moderate symptoms in ASA-sensitive patients. PeptLTs, LTB4, 15-HETE, PGE2, PGF2 alpha, and PGD2 were measured by radioimmunoassay methods. Significant levels of PeptLTs were detected in sensitive asthmatic patients 60 min after nasal challenge. This change was associated with a significant increase in symptoms. No increase in PeptLTs levels were found, however, in either insensitive patients or healthy subjects. Inhibition of PGE2 and PGF2 alpha release was detected in the three groups after ASA administration. ASA also inhibited PGD2 release in insensitive asthmatic patients but not in both sensitive patients and healthy subjects. These results suggest that an abnormal release of PeptLTs in ASA-sensitive asthmatic patients contributes to nasal and bronchial adverse reactions. The lack of effects on PGD2 release suggests that mast cells from ASA-insensitive patients are more sensitive to ASA than those from sensitive asthmatic patients and healthy subjects.

The effects of intermittent negative pressure ventilation have been studied in 20 patients with chronic obstructive pulmonary disease during an exacerbation of their disease. Measurements of arterial blood gas tensions and maximal inspiratory pressure (MIP) were performed before and after six hours of negative pressure ventilation or standard treatment (control day) given in random order on two consecutive days. After negative pressure ventilation the mean (SD) value of MIP increased from 68.1 (21.5) to 74.8 (20) cm H2O;* arterial oxygen tension (PaCO2) fell from 60.6 (12.2) to 50.9 (8.9) mm Hg* but PaO2 changed little (from 48.4 (7.4) to 47.6 (8.2) mm Hg). There were no significant changes on the control day in arterial blood gas tensions (PaO2 47.8 (8.1) and 48.9 (9.4) and Paco2 59.8 (10.9) and 57.5 (8.06) mm Hg) or in MIP (69.4 (22.4) and 70.9 (22.9) cm H2O). Six patients tolerated negative pressure ventilation poorly and these patients showed less improvement after negative pressure ventilation. Our results suggest that intermittent negative pressure ventilation can increase alveolar ventilation in patients with an exacerbation of chronic obstructive lung disease, particularly in those who tolerate the procedure well. Most subjects showed a fall in PaCO2 and an increase in MIP. The fact that PaO2 was unchanged despite the fall in PaCO2 suggests that gas exchange may deteriorate with negative pressure ventilation in these patients.

The purpose of this study was to analyse the validity and the economic efficiency of a portable monitor of respiratory parameters (PMRP), used in a home setting for the diagnosis of sleep apnoea/hypopnoea syndrome (SAHS). Eighty nine patients with suspected SAHS were studied in two settings: in the sleep laboratory using full-polysomnography (full-PSG); and at the patient's home using a PMRP. In the home setting, 50 patients were assisted by a technician and 39 set up the equipment themselves. SAHS (apnoea/hypopnoea index (AHI) >10 events x h(-1) by means of full-PSG) was diagnosed in 75 of the 89 patients. An acceptable agreement was obtained between the AHI measured by full-PSG and PMRP, according to the Bland and Altman method of concordance (mean bias 2.56; 95% confidence interval 3.25). Sensitivity and specificity of PMRP were adequate for diagnostic purposes; however, their values rely on the prior PMRP-AHI cut-off point selected with reference to full-PSG-AHI >10. The clinical therapeutic decision taken after PMRP agreed with that taken with full-PSG in 79 patients (89%). Although 10% of the studies with an individual set-up needed repetition, both of the domiciliary modalities (with and without a technician's intervention) were, economically, about three times more efficient than full-PSG. In conclusion, we believe that patients with a suspected sleep apnoea/hypopnoea syndrome should initially be studied in a home setting with a portable monitor of respiratory parameters, since it is a reliable method with an acceptable cost-effective profile.