RESUMO
BACKGROUND: Although obstructive sleep apnea (OSA) has long been associated with daytime sleepiness, far less is known about its association with the ability to remain awake. The aim of this study was to examine the relative importance of inter-correlated measures of OSA severity (eg, various indices of oxygen saturation and sleep fragmentation) in the ability to stay alert as measured objectively by the Maintenance of Wakefulness Test (MWT), defined by a mean sleep latency of ≥12 min. METHODS: Seventy-eight obese women and men of similar age and body mass index living at altitude (Mexico City) underwent standard polysomnography, MWT, and completed validated sleep-related questionnaires. RESULTS: Men had more severe sleep apnea than women (p = 0.002) and were also less alert on MWT (p = 0.022). Logistic regression models indicated that measures of desaturation consistently predicted MWT-defined alertness, whereas varied measures of sleep fragmentation did not. Nearly a third of the variance (r(2) = 0.304) in MWT-defined alertness was accounted for by the number of desaturations per hour of sleep (p = 0.003), which is considerably higher than other studies have reported in different populations. CONCLUSION: The ability to remain awake in obese patients is best accounted for by hypoxemia rather than sleep fragmentation. Whether the size of this effect reflects differences in the population under study (eg, extent of obesity, racial background, residence at moderate altitude) and/or is a function of the measurement of alertness with the MWT remains uncertain.
Assuntos
Altitude , Hipóxia/complicações , Obesidade , Apneia Obstrutiva do Sono/complicações , Vigília/fisiologia , Adulto , Feminino , Humanos , Masculino , México , Polissonografia , Fases do Sono/fisiologia , Inquéritos e QuestionáriosRESUMO
STUDY OBJECTIVES: Sleep disordered breathing (SDB) is a highly prevalent condition in high-income countries, with major consequences for cardiopulmonary health, public safety, healthcare utilization, and mortality. However, its prevalence and effect in low- and middle-income countries are less well known. We sought to determine the prevalence, risk factors, and comorbidities of SDB symptoms in four resource-limited settings. DESIGN: Cross-sectional analysis of the CRONICAS Cohort, a population-based age- and sex-stratified sample. SETTING: Four resource-limited settings in Peru varying in altitude, urbanization, and air pollution. PARTICIPANTS: There were 2,682 adults aged 35 to 92 y. MEASUREMENTS AND RESULTS: Self-reported SDB symptoms (habitual snoring, observed apneas, Epworth Sleepiness Scale), sociodemographics, medical history, anthropometrics, spirometry, blood biomarkers were reported. We found a high prevalence of habitual snoring (30.2%, 95% confidence interval [CI] 28.5-32.0%), observed apneas (20.9%, 95% CI 19.4-22.5%) and excessive daytime sleepiness (18.6%, 95% CI 17.1-20.1%). SDB symptoms varied across sites; prevalence and adjusted odds for habitual snoring were greatest at sea level, whereas those for observed apneas were greatest at high altitude. In multivariable analysis, habitual snoring was associated with older age, male sex, body mass index (BMI), and higher socioeconomic status; observed apneas were associated with BMI; and excessive daytime sleepiness was associated with older age, female sex, and medium socioeconomic status. Adjusted odds of cardiovascular disease, depression, and hypertension and total chronic disease burden increased progressively with the number of SDB symptoms. A threefold increase in the odds of having an additional chronic comorbid disease (adjusted odds ratio 3.57, 95% CI 2.18-5.84) was observed in those with all three versus no SDB symptoms. CONCLUSIONS: Sleep disordered breathing symptoms were highly prevalent, varied widely across four resource-limited settings in Peru, and exhibited strong independent associations with chronic diseases.