***TASK*** the task is to summarize an input biomedical literature in six sentences 
    ***INPUT*** the input is a biomedical literature 
    ***OUTPUT*** the output is the summary of an input biomedical literature in six sentences 
    ***DOCUMENTATION*** 
    ***EXAMPLES*** 
    Input: The aim of this study was to evaluate prevalence of obstructive sleep apnea among patients undergoing bariatric surgery  and the predictive value of various clinical parameters : body mass index ( BMI ) , neck circumference ( NC ) and the Epworth Sleepiness Scale ( ESS ) . We performed a prospect i ve , multidisciplinary , single-center observational study including all patients on the waiting list for bariatric surgery between June 2009 and June 2010 , irrespective of history or clinical findings . Patients visited our ENT outpatient clinic for patient history , ENT and general examination and underwent a full night polysomnography , unless performed previously . As much as 69.9 % of the patients fulfilled the criteria for OSA ( mean BMI 44.2 ± SD 6.4 kg/m2 ) ; 40.4 % of the patients met the criteria for severe OSA . The regression models found BMI to be the best clinical predictor , while the ROC curve found the NC to be the most accurate predictor of the presence of OSA . The discrepancy of the results and the poor statistical power suggest that all three clinical parameters are inadequate predictors of OSA . In conclusion , in this large patient series , 69.9 % of patients undergoing BS meet the criteria for OSA . More than 40 % of these patients have severe OSA . A mere 13.3 % of the patients were diagnosed with OSA before being placed on the waiting list for BS . On statistical analysis , increased neck circumference , BMI and the ESS were found to be insufficient predictors of the presence of OSA . Polysomnography is an essential component of the preoperative workup of patients undergoing BS . When OSA is found , specific perioperative measures are indicated BACKGROUND Limited data have suggested that sleep-disordered breathing , a condition of repeated episodes of apnea and hypopnea during sleep , is prevalent among adults . Data from the Wisconsin Sleep Cohort Study , a longitudinal study of the natural history of cardiopulmonary disorders of sleep , were used to estimate the prevalence of undiagnosed sleep-disordered breathing among adults and address its importance to the public health . METHODS A r and om sample of 602 employed men and women 30 to 60 years old were studied by overnight polysomnography to determine the frequency of episodes of apnea and hypopnea per hour of sleep ( the apnea-hypopnea score ) . We measured the age- and sex-specific prevalence of sleep-disordered breathing in this group using three cutoff points for the apnea-hypopnea score ( > or = 5 , > or = 10 , and > or = 15 ) ; we used logistic regression to investigate risk factors . RESULTS The estimated prevalence of sleep-disordered breathing , defined as an apnea-hypopnea score of 5 or higher , was 9 percent for women and 24 percent for men . We estimated that 2 percent of women and 4 percent of men in the middle-aged work force meet the minimal diagnostic criteria for the sleep apnea syndrome ( an apnea-hypopnea score of 5 or higher and daytime hypersomnolence ) . Male sex and obesity were strongly associated with the presence of sleep-disordered breathing . Habitual snorers , both men and women , tended to have a higher prevalence of apnea-hypopnea scores of 15 or higher . CONCLUSIONS The prevalence of undiagnosed sleep-disordered breathing is high among men and is much higher than previously suspected among women . Undiagnosed sleep-disordered breathing is associated with daytime hypersomnolence CONTEXT Excess body weight is positively associated with sleep-disordered breathing ( SDB ) , a prevalent condition in the US general population . No large study has been conducted of the longitudinal association between SDB and change in weight . OBJECTIVE To measure the independent longitudinal association between weight change and change in SDB severity . DESIGN Population -based , prospect i ve cohort study conducted from July 1989 to January 2000 . SETTING AND PARTICIPANTS Six hundred ninety r and omly selected employed Wisconsin residents ( mean age at baseline , 46 years ; 56 % male ) who were evaluated twice at 4-year intervals for SDB . MAIN OUTCOME MEASURES Percentage change in the apnea-hypopnea index ( AHI ; apnea events + hypopnea events per hour of sleep ) and odds of developing moderate-to-severe SDB ( defined by an AHI > or = 15 events per hour of sleep ) , with respect to change in weight . RESULTS Relative to stable weight , a 10 % weight gain predicted an approximate 32 % ( 95 % confidence interval [ CI ] , 20%-45 % ) increase in the AHI . A 10 % weight loss predicted a 26 % ( 95 % CI , 18%-34 % ) decrease in the AHI . A 10 % increase in weight predicted a 6-fold ( 95 % CI , 2.2 - 17.0 ) increase in the odds of developing moderate-to-severe SDB . CONCLUSIONS Our data indicate that clinical and public health programs that result in even modest weight control are likely to be effective in managing SDB and reducing new occurrence of SDB Daytime sleepiness , impaired cognitive performance and dysphoric mood are often present in patients with obstructive sleep apnoea syndrome ( SAS ) . This prospect i ve controlled study evaluates the effects of treatment with continuous positive airway pressure ( CPAP ) during 1 yr on daytime functioning in a large group of patients with SAS . The authors studied 80 patients ( mean+/-sem 49+/-1 yrs ) with SAS with a mean apnoea-hypopnoea index of 60+/-2 h-1 , and 80 healthy control subjects matched for sex and age ( 46+/-1 yrs . ) . Measurements were obtained at the beginning of the study and 12+/-1 months later , and included : daytime sleepiness ( Epworth scale ) , depression and anxiety ( Beck tests ) , vigilance ( Steer-Clear ) and reaction time ( Psychometer Vigilance Test 192 ) . Drug , coffee and alcohol intake , as well as the sleep schedule , were also recorded . Results showed that , before treatment , patients were more somnolent ( p<0.001 ) , anxious ( p<0.01 ) and depressed ( p<0.001 ) than control subjects . Also , they had a longer reaction time ( p<0.05 ) and poorer vigilance ( p<0.01 ) . The use of CPAP improved significantly the levels of somnolence ( p<0.0001 ) and vigilance ( p<0.01 ) , but failed to modify anxiety and depression . Reaction time changes were minor . Variables with a potential confounding effect did not change during the study . These results provide firm evidence to substantiate the use of continuous positive airway pressure in patients with sleep apnoea syndrome BACKGROUND Results of clinical studies suggest that there may be a relationship between breathing-related sleep disorders and depressive disorders . This study aims to assess the impact of breathing-related sleep disorder on major depressive disorder in the general population . METHOD A cross-sectional telephone survey was carried out between 1994 and 1999 in the general population of the United Kingdom , Germany , Italy , Portugal , and Spain . A total of 18,980 r and omly selected subjects aged 15 to 100 years and representative of the general population of their respective countries participated in the study . The question naire included a series of questions about  sleep quality , breathing-related sleep disorder symptoms , mental disorders , and medical conditions . Data are presented using point prevalence . RESULTS 2.1 % of the subjects were found with  obstructive sleep apnea syndrome  at the time of the interview , and 2.5 % had some other type of DSM-IV breathing-related sleep disorder diagnosis . The association of DSM-IV breathing-related sleep disorder diagnosis and major depressive disorder diagnosis was found in 0.8 % of the sample . As many as 18 % of individuals with a major depressive disorder diagnosis also have a DSM-IV breathing-related sleep disorders diagnosis , and 17.6 % of subjects with a DSM-IV breathing-related sleep disorders diagnosis have a major depressive disorder diagnosis . Multivariate models showed that even after controlling for obesity and hypertension , the odds of having a DSM-IV breathing-related sleep disorders diagnosis was 5.26 for individuals with a major depressive disorder diagnosis . CONCLUSION About 800 of 100,000 individuals have both a breathing-related sleep disorder and a major depressive disorder . The identification of 1 of these 2 disorders should prompt the investigation of the other disorder since nearly a fifth of them have the other disorder 
    Output:
    
People with SMI ( particularly MDD ) have a high prevalence of OSA .