Association between insomnia phenotypes and subclinical myocardial injury: the Multi-Ethnic Study of Atherosclerosis.

STUDY OBJECTIVES: To assess whether the association between insomnia and subclinical myocardial injury, as measured by cardiac troponin T (cTnT), differs across insomnia phenotypes. METHODS: We measured cTnT in 2188 participants in the Multi-Ethnic Study of Atherosclerosis study who had completed sleep questionnaires and undergone unattended polysomnography (PSG) and 7-day actigraphy. Insomnia symptoms were defined as reporting at least one of the following ≥5 nights/week over the past 4 weeks: trouble falling asleep, waking up several times a night, having trouble getting back to sleep after waking up too early, or taking sleeping pills to help falling asleep. Obstructive sleep apnea (OSA) was defined as an apnea-hypopnea index (AHI >15 events/h). Participants were classified into insomnia phenotypes, including comorbid insomnia and OSA (COMISA) and insomnia associated with actigraphy-estimated short sleep (<6 h) or sleep fragmentation. RESULTS: The mean age was 68.8 (SD 9.2) years, 53.6% were male. In total, 47.8% met threshold levels for insomnia symptoms, and 43.1% had an AHI >15. In adjusted linear regression models COMISA (ß 0.08 [standard error (SE) 0.03], p < .01) and insomnia with short sleep duration (ß 0.07 [SE 0.03], p < .05) were each associated with higher cTnT compared to a reference group with no insomnia. Insomnia with fragmented sleep (ß 0.03 [SE 0.02]) was not associated with higher cTnT (p > .05) in adjusted analyses. OSA was associated with higher cTnT (ß 0.09 [SE 0.03], p < .01) in adjusted models. CONCLUSIONS: COMISA and insomnia with short sleep duration, but not insomnia symptoms alone or fragmented sleep, were associated with increased circulating cTnT in older adults.

Prevalence of sleepiness and associations with quality of life in patients with sleep apnea in an online cohort.

STUDY OBJECTIVES: Excessive daytime sleepiness (EDS) is a treatment target for many patients with obstructive sleep apnea (OSA). We aimed to understand the prevalence, risk factors, and quality of life associated with EDS in a nonclinical, "real world" sample of patients with OSA. METHODS: Cross-sectional survey of patients with OSA participating in an online peer support community, assessing demographics, comorbidities, treatment, and quality of life. Differences in those with and without EDS (Epworth Sleepiness Scale > and ≤ 10) were assessed. RESULTS: The sample (n = 422) was 54.2% male, 65.9% were ≥ 55 years, and 43.3% reported sleeping ≤ 6 hours/night. EDS was identified among 31.0% of respondents and 51.7% reported sleepiness as a precipitating factor for seeking initial OSA treatment. EDS was more prevalent in individuals reporting asthma, insomnia symptoms, positive airway pressure (PAP) use less than 6 hours/night on ≥ 5 nights/week, or sleep duration < 6 hours/night. After adjusting for demographics and comorbidities, patients with EDS reported poorer mental and physical health and well-being, lower disease-specific functional status, more activity and work impairment, and more driving impairment (P values < .05). In the subsample (n = 265) with high PAP adherence, 26.0% reported EDS, and similar associations between EDS and outcomes were observed. CONCLUSIONS: These "real world" data suggest that patients seeking online OSA support experience a high prevalence of EDS, which was associated with poorer quality of life and worse functional status. Associations persisted among respondents with high self-reported PAP-therapy adherence, potentially driving these individuals to seek online support for sleepiness-related symptoms. CITATION: Wanberg LJ, Rottapel RE, Reid ML, et al. Prevalence of sleepiness and associations with quality of life in patients with sleep apnea in an online cohort. J Clin Sleep Med. 2021;17(12):2363-2372.

Characterization of lung-to-finger circulation time in sleep study assessment: the Multi-Ethnic Study of Atherosclerosis.

OBJECTIVES: Lung-to-finger circulation time (LFCT) measured from sleep studies may reflect underlying cardiac dysfunction. We aimed to examine the distribution of LFCT in community-dwelling men and women in order to better understand the factors determining LFCT between and within subjects. APPROACH: We included participants of the Multi-Ethnic Study of Atherosclerosis (MESA) Sleep with polysomnography-based evidence of sleep apnea (defined by apnea hypopnea index >15 hr-1). In a randomly selected subset of the analytical dataset, we tested an automated LFCT measurement method against the visual method. Using the automated method we then scored LFCTs from all eligible respiratory events for all included participants. A multiple regression model was constructed to determine factors independently associated with average LFCT across subjects. We also explored factors that are associated with LFCT within subjects using linear mixed-effect models. MAIN RESULTS: In a subset of the cohort (N = 39) there was a high correlation in average LFCT obtained by automated and visual methods (r = 0.96). In the analysis of 596 participants, men [19.6 (2.8)] (vs. women [17.9 (2.7) s], p < 0.0001) and older age (> 69 (vs. ≤ 69) had longer average LFCT (19.4 [2.8] vs. 18.5 [2.9] s, p < 0.0001). These associations persisted in multivariable analysis. No association was found with body habitus. Within subject analysis revealed trivial associations between apnea/hypopnea duration, apnea (vs. hypopnea), nadir O2 saturation and sleep stages (NREM vs. REM) and individual LFCT. SIGNIFICANCE: Automated LFCT measurement was highly correlated with visual-based LFCT measurement. In this group of community-dwelling adults, male sex and older age were associated with higher average LFCT.

The role of sham continuous positive airway pressure as a placebo in controlled trials: Best Apnea Interventions for Research Trial.

STUDY OBJECTIVES: The main objective of this study was to evaluate the role of sham continuous positive airway pressure (CPAP) compared to conservative medical therapy (CMT) as a control arm in the Best Apnea Interventions for Research (BestAIR) study by assessing differences in subjectively and objectively measured outcomes, adverse events, adherence, and retention rates. METHODS: BestAIR is a clinical trial aimed to identify important design features for future randomized controlled trials of CPAP. Participants with obstructive sleep apnea were randomized to one of four groups; two control arms (CMT, sham-CPAP) and two active CPAP arms (with and without behavioral interventions). Blood pressure and health-related quality of life outcomes were assessed at baseline, 6 and 12 months. Study outcomes, retention, and adverse event rates were compared between the two control arms. Sham-CPAP adherence and self-efficacy were also compared to active-CPAP adherence (without behavioral intervention). RESULTS: Our sample included 86 individuals in the control arms and 42 participants in the active-CPAP arm. There were no differences in longitudinal profiles in blood pressure, health-related quality of life outcomes, dropout rates, or adverse events in sham-CPAP group compared to CMT-only group (all ps > 0.05); standardized differences were generally small and with inconsistent directionality across measurements. When compared to active-CPAP, sham-CPAP was associated with 93 fewer minutes/night of usage over 12 months (p = 0.007) and lower outcome expectations (p < 0.05). CONCLUSION: We observed no evidence of differences in objectively or subjectively measured outcomes with the use of sham-CPAP compared to CMT group. The lower adherence on sham-CPAP and poorer self-efficacy compared to active-CPAP may suggest differences in perceived benefit. REGISTRATION: NCT01261390 Best Apnea Interventions for Research (BestAIR) www.clinicaltrials.gov.

S reactivity of an oil sands composite tailings deposit undergoing reclamation wetland construction.

This study is the first to characterize the S stability of a composite tailings (CT) deposit undergoing pilot wetland reclamation in the Athabasca Oil Sands Region (AOSR, Alberta, Canada). As CT is sulfur, organic carbon and bacterially rich, the goal of this study was to characterize the in situ aqueous distribution of sulfur compounds across the wetland, sand cap and underlying CT zones of the deposit, in an effort to establish the potential for microbial sulfur cycling and generation of H2S, an explosive, corrosive and toxicity risk. Porewater samples from three depths spanning the different layers of the deposit, as well as wetland surface ponded water samples were collected for geochemical analyses (July and Sept 2013), and for microbial enrichments (both S reducing and S oxidizing bacteria) in June 2014. While porewater ΣH2S(aq) was detected at all depths across the three zones of the deposit, results identify that the sand cap layer required for construction, acts as a mixing zone generating the highest solution H2S concentrations (>500 uM or 18 mg/L) and H2S gas levels (over 100 and up to 180 ppm) observed. Porewater dissolved sulfate concentrations (0.14-6.97 mM) were orders of magnitude higher and did not correlate to the observed distribution of ΣH2S concentrations throughout the deposit. Unique to the sandcap, dissolved organic carbon positively correlated with the observed maxima of ΣH2S(aq) seen in this layer. The water management of the deposit is a critical factor in the observed S trends. Active dewatering of the CT resulted in migration of S rich water up into the sandcap, while downwelling labile organic carbon from the developing wetland acted in concert to stimulate microbial generation of the H2S in this structural layer to the highest levels observed. Functional enrichments identified that diverse S reducing and oxidizing microbial metabolisms are widespread throughout the deposit, indicating that these waste materials are biogeochemically reactive with implications for longterm stability. These results are of relevance to both the oil sands region, as well as other mine contexts where S rich wastes occur, identifying the need to consider the potential bacterially driven cycling of S and C in the generation of constituents of concern, as well as the water management of such waste deposits to minimize risk.

Real-time translocation of fullerene reveals cell contraction.

Carbon-based nanomaterials possess unique structural, mechanical, and electronic properties that are exploited in numerous applications. The fate of nanomaterials in living systems and in the environment is largely unknown, though there is a reason for concern. Here it is shown how the interaction of fullerene with natural phenolic acid induces cell contraction. This phenomenon has a general applicability to carbon-based nanomaterials interacting with natural amphiphiles. Atomistic simulations reveal that the self-assembly of C(70)-gallic acid (GA) favors aggregation. Confocal fluorescence microscopy shows that C(70)-GA complexes translocate across the membranes of HT-29 cells and enter nuclear membranes. Confocal imaging further reveals the real-time uptake of C(70)-GA and the consequent contraction of the cell membranes. This contraction is attributed to the aggregation of nanoparticles into microsized particles promoted by cell surfaces, a new physical mechanism for deciphering nanotoxicity.