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This study aimed to identify determinants of objectively-estimated bedtime habits and to determine if these bedtime habits differed between adults with and without type 2 diabetes. Adults with accelerometry data from the National Health and Nutrition Examination Survey 2003-2004 and 2005-2006 cohorts were classified as having no diabetes or type 2 diabetes and matched for age, gender, and BMI across the two groups. Multivariate linear regression models assessed bedtime habits (time-in-bed, early versus late bedtime periods, regularity), chronotype (mid-points), and type 2 diabetes status. While the results indicated no differences in bedtime habits between adults with and without type 2 diabetes, an interesting finding was the support for an association between objectively-estimated earlier bedtime midpoints and greater physical activity. Keywords: sleep, sleep behavior, chronotype, bedtime, social jetlag, type 2 diabetes, Introduction Lifestyle modification programs are twice as effective in preventing type 2 diabetes than pharmacological interventions (Diabetes Prevention Program Research Group, 2002). Approaches that build on the success of these [...]

Rationale: Nocturnal hypoxemia is common in sleep-disordered breathing (SDB) and is associated with increased morbidity and mortality. Although impaired diffusing capacity of the lung for carbon monoxide (DlCO) is associated with daytime hypoxemia, its influence on SDB-related nocturnal hypoxemia is not known. Objectives: To characterize the effects of DlCO impairment on SDB-related nocturnal hypoxemia and associated health outcomes. Methods: Data from a multicenter cohort of men with and without human immunodeficiency virus (HIV) infection, with concomitant measures of DlCO and home-based polysomnography (n = 544), were analyzed. Multivariable quantile regression models characterized associations between DlCO and several measures of SDB-related hypoxemia (e.g., total sleep time with oxygen saturation as measured by pulse oximetry [SpO2] < 90% [T90]). Structural equation models were used to assess associations of impaired DlCO and SDB-related hypoxemia measures with prevalent hypertension and type 2 diabetes. Results: DlCO impairment (<80% predicted) was associated with sleep-related hypoxemia. Participants with severe SDB (apnea–hypopnea index ⩾ 30 events/h) and impaired DlCO had higher T90 (median difference, 15.0% [95% confidence interval (CI), 10.3% to 19.7%]) and average SDB-related desaturation (median difference, 1.0 [95% CI, 0.5 to 1.5]) and lower nadir SpO2 (median difference, −8.2% [95% CI, −11.4% to −4.9%]) and average SpO2 during sleep (median difference, −1.1% [95% CI, −2.1% to −0.01%]) than those with severe SDB and preserved DlCO. Higher T90 was associated with higher adjusted odds of prevalent hypertension (odds ratio, 1.39 [95% CI, 1.14 to 1.70]) and type 2 diabetes (odds ratio, 1.25 [95% CI, 1.07 to 1.46]). Conclusions: DlCO impairment in severe SDB was associated with sleep-related hypoxemia, prevalent hypertension, and type 2 diabetes. Assessment of SDB should be considered in those with impaired DlCO to guide testing and risk stratification strategies. [ABSTRACT FROM AUTHOR]

Background: Sleep-disordered breathing (SDB) is a known risk factor for hypertension. Despite the well-established link between HIV infection and hypertension, it remains to be determined whether HIV infection modifies the association between SDB and hypertension. Setting: The Multicenter AIDS Cohort Study. Methods: SDB was assessed using in-home polysomnography in 779 men (436 with and 343 without HIV). The apnea-hypopnea index (AHI) based on oxyhemoglobin desaturation threshold of ≥3% or arousal (AHI 3a ) and ≥4% (AHI 4 ) along with oxygen desaturation index (ODI) were used to quantify SDB severity. Hypertension was defined as a blood pressure ≥140/90 mm Hg, use of antihypertensive medication, or self-report of a clinical diagnosis. The associations between HIV, SDB, and hypertension were characterized using multivariable logistic regression. Results: The prevalence of hypertension and SDB (AHI3a ≥ 5 events/hr) was high, with estimates of 53.8% and 82.8%, respectively. Among men without SDB, HIV was independently associated with hypertension, with an adjusted odds ratio (OR) of 3.05 [95% confidence interval (CI): 1.33 to 7.01]. In men without HIV, SDB was associated with hypertension (OR: 2.93; 95% CI: 1.46 to 5.86). No significant increase in the odds of hypertension was noted in men with both HIV and SDB compared with men with either factor alone, with an OR of 3.24 (95% CI: 1.62 to 6.47). These results were consistent across different measures used to define SDB (AHI3a, AHI4, ODI3, and ODI4). Conclusions: Predictors of hypertension differed by HIV status. SDB was associated with hypertension in men without HIV, but not in men with HIV. Among men with HIV, SDB did not affect the odds of hypertension. [ABSTRACT FROM AUTHOR]

Continuous glucose monitors (CGMs) are increasingly used to measure blood glucose levels and provide information about the treatment and management of diabetes. Our motivating study contains CGM data during sleep for 174 study participants with type II diabetes mellitus measured at a 5‐min frequency for an average of 10 nights. We aim to quantify the effects of diabetes medications and sleep apnea severity on glucose levels. Statistically, this is an inference question about the association between scalar covariates and functional responses observed at multiple visits (sleep periods). However, many characteristics of the data make analyses difficult, including (1) nonstationary within‐period patterns; (2) substantial between‐period heterogeneity, non‐Gaussianity, and outliers; and (3) large dimensionality due to the number of study participants, sleep periods, and time points. For our analyses, we evaluate and compare two methods: fast univariate inference (FUI) and functional additive mixed models (FAMMs). We extend FUI and introduce a new approach for testing the hypotheses of no effect and time invariance of the covariates. We also highlight areas for further methodological development for FAMM. Our study reveals that (1) biguanide medication and sleep apnea severity significantly affect glucose trajectories during sleep and (2) the estimated effects are time invariant. [ABSTRACT FROM AUTHOR]

Continuous positive airway pressure (CPAP) is the first-line treatment for obstructive sleep apnea (OSA). Although CPAP improves symptoms (e.g., daytime sleepiness), there is a lack of high-quality evidence that CPAP prevents many long-term outcomes, including cognitive impairment, myocardial infarction, and stroke. Observational studies suggest that patients with symptoms may be particularly likely to experience these preventive benefits with CPAP, but ethical and practical concerns limited the participation of such patients in prior long-term randomized trials. As a result, there is uncertainty about the full benefits of CPAP, and resolving this uncertainty is a key priority for the field. This workshop assembled clinicians, researchers, ethicists, and patients to identify strategies to understand the causal effects of CPAP on long-term clinically important outcomes among patients with symptomatic OSA. Quasi-experimental designs can provide valuable information and are less time and resource intensive than trials. Under specific conditions and assumptions, quasi-experimental studies may be able to provide causal estimates of CPAP's effectiveness from generalizable observational cohorts. However, randomized trials represent the most reliable approach to understanding the causal effects of CPAP among patients with symptoms. Randomized trials of CPAP can ethically include patients with symptomatic OSA, as long as there is outcome-specific equipoise, adequate informed consent, and a plan to maximize safety while minimizing harm (e.g., monitoring for pathologic sleepiness). Furthermore, multiple strategies exist to ensure the generalizability and practicality of future randomized trials of CPAP. These strategies include reducing the burden of trial procedures, improving patient-centeredness, and engaging historically excluded and underserved populations. [ABSTRACT FROM AUTHOR]