Scores of a web-based version of the Seasonal Pattern Assessment Questionnaire in Brazil

Seasonal affective disorder (SAD) is a proposed mental disorder still controversial. This condition is prevalent in northern latitudes, but few studies have been conducted at locations in the southern hemisphere. It is usually assessed by the Seasonal Pattern Assessment Questionnaire (SPAQ). This study aimed to evaluate, through on-line questionnaire, the hypothesis that, in the Brazilian population, latitude and longitude influence SPAQ scores. Methods: An advertisement was posted on a sleep medicine website inviting visitors to investigate seasonal patterns of behavior and mood, using a Brazilian Portuguese version of the SPAQ. The geographic coordinates of the place of residence of each respondent were analyzed as a continuous variable or distributed in quartiles of latitude and longitude. The psychometric properties of the SPAQ were assessed by reliability and factor analyses. Results: Answers from 1001 respondents out of 1045 were considered eligible. High SPAQ scores were observed in 287 respondents, equally distributed among all latitude and longitude quartiles. Data collected in different seasons and during daylight saving time did not differ significantly in any of the scores for SPAQ dimensions. No correlations between SPAQ scores and latitude or longitude were observed. Psychometric properties of the SPAQ were preserved in all geographic locations. Conclusion: The finding of similar SPAQ scores at a wide latitude range defies the concept of SAD symptoms as latitude or longitude-dependent phenomena...

Is sleep apnea a winter disease?: meteorologic and sleep laboratory evidence collected over 1 decade.

BACKGROUND: The severity of obstructive sleep apnea increases by influence of conditions that are more frequent in winter. The hypothesis that the apnea-hypopnea index (AHI) of different patients undergoing polysomnography may be seasonally affected was tested. METHODS: The retrospectively analyzed database included 7,523 patients of both sexes who underwent in-laboratory baseline polysomnography to investigate any complaint of disordered sleep, during 1 decade, between January 2000 and December 2009. Data on climate and air pollution were obtained from official organizations. AHI was the main outcome variable. Cosinor analysis, a statistical method for the investigation of time series, was used to detect seasonality. RESULTS: The cosinor analysis confirmed the existence of a circannual pattern of AHI, with acrophase in winter and nadir during the summer. The seasonality is significant even after adjusting for sex, age, BMI, neck circumference, and relative air humidity. Median (25-75 interquartile range) AHI in the 6 months with colder weather was 17.8 (6.5-40.6/h), and in the warmer weather was 15.0 (5.7-33.2/h). The AHI correlated inversely with ambient temperature and directly with atmospheric pressure, relative air humidity, and carbon monoxide levels. Correlations with precipitation, particulate air matter < 10 µm, sulfur dioxide, and ozone were nonsignificant. CONCLUSIONS: More sleep-disordered breathing events were recorded in winter than in other seasons. Cosinor analysis uncovered a significant seasonal pattern in the AHI of different patients undergoing polysomnography, independent of sex, age, BMI, neck circumference, and relative air humidity. This finding suggests that obstructive sleep apnea severity may be associated with other seasonal epidemiologic phenomena.

Immediate and overnight recumbence-dependent changes of neck circumference: relationship with OSA severity in obese and nonobese subjects.

BACKGROUND: Overnight increases in neck circumference - attributed to rostral fluid displacement - correlate with the severity of obstructive sleep apnea (OSA). No studies were found investigating the relationship between OSA severity and recumbence-related immediate changes in neck circumference. We evaluated the relationship of OSA severity with immediate recumbence-related and overnight changes in neck circumference in obese and nonobese subjects. METHODS: Male patients undergoing full-night in-laboratory polysomnography had their neck and ankle circumferences determined before and after sleep, both while standing and supine. Circumference changes were calculated by the difference between standing and recumbent positions (Immediate Change) and between before and after sleep (Overnight Change). RESULTS: Immediate Change in neck circumference showed a linear significant correlation with apnea-hypopnea index (AHI; r=0.37373; p=0.012) and with lowest O2 saturation (r=-0.35355; p=0.017). In a multivariate model to predict AHI, adjusting for age and obesity, Immediate Change in neck circumference is the only significant regressor (beta=0.34; p=0.03). The Overnight Change in neck circumference correlated neither with the AHI nor with the lowest SaO2. CONCLUSION: Correlation of AHI with the immediate increase in neck circumference on assuming recumbence indicates that fast components of tissue displacement, besides overnight fluid displacement, may have implications in the pathogenesis of OSA.

High risk for sleep apnea in the Berlin questionnaire and coronary artery disease.

INTRODUCTION: Obstructive sleep apnea (OSA) affects up to 30% of the adult population and is a risk factor for coronary artery disease (CAD). The diagnostic process, involving polysomnography, may be complex. Berlin questionnaire (BQ) is a validated and economical screening tool. PURPOSE: The aim of this study was to assess the performance of the BQ for the diagnosis of OSA in individuals with angina complaints. METHODS: Patients undergoing diagnostic cineangiography, portable type III polysomnography to determine the apnea-hypopnea index (AHI), and who answered the BQ were included. We excluded patients older than 65 years that were smokers, diabetics, and morbidly obese. High risk for OSA was based on positive responses in two of three symptom criteria of the BQ. CAD was defined by the presence of >50% lesion in coronary arteries. RESULTS: In 57 included cases, high risk in the BQ indicates significant odds ratio [95% confidence interval] for the presence of CAD (4.5[1.03-19.25], P = 0.045), adjusted for usual confounders: gender, age, and body mass index. The sensitivity and the specificity of BQ for CAD were 70% and 48%, respectively; the positive and negative predictive values are 56% and 64%. CONCLUSIONS: In conclusion, simple questionnaire-based diagnostic tools can be included in the screening procedures of patients with angina to detect the need for further OSA evaluation. In conclusion, the BQ is an effective instrument for this purpose.

Sleep apnea is a stronger predictor for coronary heart disease than traditional risk factors.

BACKGROUND: Sleep apnea (SA) may be linked to coronary artery disease (CAD). Both conditions have similar risk factors, confounding the analyses. Investigation of the lipid profile is routine in the adult population, even without symptoms or suspected cardiac ailment. SA, however, remains underdiagnosed even in the presence of unambiguous clinical manifestations. PURPOSE: The aim of this study was to verify the association between SA and CAD, adjusting for usual CAD risk factors. METHODS: Patients who underwent diagnostic or therapeutic coronariography and portable type III polysomnography were studied. The severity of SA was determined by the apnea-hypopnea index (AHI). We measured classic CAD risk factors: fasting glucose; total, HDL, and LDL cholesterols; triglycerides; uric acid, and high-sensitivity C-reactive protein. We excluded patients older than 65 years, with body mass index higher than 40 kg/m(2), with diabetes, and with history of smoking in the last year. RESULTS: Of 55 included patients, 28 had AHI > 14, showing an odds ratio of 8.7 for CAD. Patients without (n = 29) and with CAD (n = 26), showed AHI of, respectively, 11 ± 11 and 23 ± 14 per hour (P = 0.001). In a binary logistic regression to predict CAD, controlling for all the above risk factors, the only variables entered in the stepwise model were AHI (either as continuous or categorical variable) and uric acid. CONCLUSION: In a sample without smokers, morbidly obese, or diabetic patients, AHI is the main predictor of CAD. SA should integrate the set of risk factors routinely assessed in clinical investigation for coronary disease risk stratification.

Repeating administration of Epworth Sleepiness Scale is clinically useful.

PURPOSE: We aimed to verify whether it is clinically useful to repeat the Epworth Sleepiness Scale (ESS) in individuals with suspected sleep-disordered breathing (SDB). METHODS: In this cross-sectional, prospective study, results of the repeated administration of the ESS were analyzed. In 929 consecutive patients, ESS was obtained as usual in the laboratory routine, immediately before the sleep study (ESS1) and was repeated in the morning, after the polysomnography (ESS2). ROC curve, classical psychometry, and item response theory (IRT) Rasch analysis were used to assess measurement properties of ESS. RESULTS: The ESS1 score was (mean ± SD), 11 ± 5.1, and the ESS2, 13 ± 4.7 (p < 0.001). Change in ESS score is explained in multivariate analysis by age, but not by gender, educational level, change in Stanford Sleepiness Scale, symptoms of sleep disorder, or polysomnography results. Accuracy of an ESS score >10 to predict apnea-hypopnea index ≥5 increased from 56% (ESS1) to 72% (ESS2). IRT psychometric properties (unidimensionality, invariance, local independence) were maintained in ESS2. CONCLUSIONS: Repeating the administration of the Epworth Sleepiness Scale in a clinical setting increases its score and diagnostic accuracy and correlation with SDB variables, without changing the psychometric properties of the scale. This experiment indicates the clinical usefulness of repeating the ESS. The scale can be repeated at a negligible cost, before dismissing individual patients on the basis of a low ESS score, discontinuing a potentially lifesaving diagnostic and therapeutic process.