The changes of AHI after long-term CPAP in patients with comorbid OSA and cardiovascular disease.

PURPOSE: To evaluate the effect of long-term continuous positive airway pressure (CPAP) treatment on disease severity of obstructive sleep apnea (OSA). METHODS: We analyzed results from the Sleep Apnea and Cardiovascular Events (SAVE) study involving participants recruited at the Guangdong Provincial People's Hospital, China. Participants were aged 45-75 years with a history of cardiac or cerebrovascular disease. OSA was confirmed by home sleep apnea testing (HSAT). Participants were randomized to receive CPAP plus standard cardiovascular care (CPAP group) or standard care alone (UC group) and followed for several years. At the study conclusion, surviving participants were invited to repeat HSAT. Changes in OSA indicators were compared by independent samples t-tests and subgroup analysis was implied among groups stratified by OSA severity. RESULTS: One hundred two adults were recruited (51 per group) and followed for 48.0 ± 14.5 months. Daily CPAP usage in the CPAP group was 4.1 ± 1.9 h. AHI decreased from baseline to end-of-study in both CPAP and UC groups (- 5.0 (- 12.5,2.0), P = 0.000; - 4.0 (- 12.5,1.5), P = 0.007, respectively), with no between-group difference (P = 0.453). An improvement in nadir SpO2 showed from baseline to end-of-study in the CPAP but not UC group (2.3% ± 6.1%, P = 0.011 and - 0.7% ± 7.6%, P = 0.511, respectively; between-group difference P = 0.032). Subgroup analysis shows that CPAP could improve AHI in patients with moderate OSA (- 8.0 (- 11.8, - 2.8) in CPAP group, - 2.0 (- 0.8,6.0) in UC group, P = 0.022) and improve nadir SpO2 in patients with severe OSA (5.0 (- 0.8, - 0.8,7.0) in CPAP group, 0.0 (- 8.5,2.5) in UC group, P = 0.032). CONCLUSION: Long-term CPAP use did not result in clinically significant changes in AHI or ODI overall but showed variable effects stratified by OSA severity. CLINICAL TRIAL REGISTRATION: Registry: Clinical Trials.gov, title: Continuous Positive Airway Pressure Treatment of Obstructive Sleep Apnea to Prevent Cardiovascular Disease (SAVE), URL: www. CLINICALTRIALS: gov , identifier: NCT00738179.

Clinical predictors of working memory performance in obstructive sleep apnea patients before and during extended wakefulness.

STUDY OBJECTIVES: Extended wakefulness (EW) and obstructive sleep apnea (OSA) impair working memory (WM), but their combined effects are unclear. This study examined the impact of EW on WM function in OSA patients and identified clinical predictors of WM impairment. METHODS: Following polysomnography (PSG), 56 OSA patients (mean ± SD, age 49.5 ± 8.9, apnea hypopnea index 38.1 ± 25.0) completed WM 2-back performance tasks 10 times over 24 h of wakefulness to assess average accuracy and completion times measured after 6-12 h awake (baseline) compared to 18-24 h awake (EW). Hierarchical cluster analysis classified participants with poorer versus better WM performance at baseline and during EW. Clinical predictors of performance were examined via regression and receiver operator characteristic (ROC) analyses. RESULTS: WM performance decreased following EW and showed consistent correlations with age, Epworth Sleepiness Score (ESS), total sleep time, and hypoxemia (O2 nadir and mean O2 desaturation) at baseline and with EW (all p < .01). O2 nadir and age were significant independent predictors of performance at baseline (adjusted R2 = 0.30, p < .01), while O2 nadir and ESS were predictors of WM following EW (adjusted R2 = 0.38, p < .001). ROC analysis demonstrated high sensitivity and specificity of models to predict poorer versus better performing participants at baseline (83% and 69%) and during EW (84% and 74%). CONCLUSIONS: O2 nadir, age, and sleepiness show prognostic value for predicting WM impairment in both rested and sleep-deprived OSA patients and may guide clinicians in identifying patients most at risk of impaired WM under both rested and heightened sleep pressure conditions.Clinical Trial Registration: This manuscript presents data collected as part of a larger trial-ANZCTR: Novel brain biomarkers of performance impairment in sleep apnea-https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=363830, No. ACTRN12613001171707.

Assessment and interpretation of sleep disordered breathing severity in cardiology: Clinical implications and perspectives.

Sleep disordered breathing (SDB) is highly prevalent in patients with atrial fibrillation, heart failure and hypertension and is associated with increased risk of mortality, cardiovascular (CV) events and arrhythmias. Current assessment of the severity of SDB is mainly based on the apnea-hypopnea index (AHI) representing the number of hypopneas and apneas per hour of sleep. However, this event-based parameter alone may not sufficiently reflect the complex pathophysiological mechanisms underlying SDB potentially contributing to CV outcome risk. In this review article, we highlight important limitations and pitfalls of current assessment, quantification and interpretation of SDB-severity in patients with CV disease and will discuss pathophysiological considerations from preclinical and clinical mechanistic studies and possible clinical implications.

Factors affecting sleep quality of patients in intensive care unit.

INTRODUCTION: Sleep disturbance is a frequently overlooked complication of intensive care unit (ICU) stay. AIM: To evaluate sleep quality among patients admitted to ICU and investigate environmental and non-environmental factors that affect sleep quality in ICU. METHODS: Over a 22-month period, we consecutively recruited patients who spent ≥ 2 nights post-endotracheal extubation in ICU and who were orientated to time, place, and person on the day of discharge. Self-reported sleep quality, according to a modified Freedman questionnaire, which provided data on self-reported ICU sleep quality in ICU and environmental factors affecting sleep quality in the ICU, were collected. We also investigated non-environmental factors, such as severity of illness, ICU interventions, and medications that can affect sleep quality. RESULTS: Fifty males and 50 females were recruited with a mean (± SD) age of 65.1 ± 15.2 years. APACHE II score at admission to ICU was 18.1 ± 7.5 with duration of stay 6.7 ± 6.5days. Self-reported sleep quality score at home (1 = worst; 10 = best) was 7.0 ± 2.2; this decreased to 4.0 ± 1.7 during their stay in ICU (p < 0.001). In multivariate analysis with APACHE III as severity of illness (R(2) = 0.25), factors [exp(b)(95% CI), p value] which significantly affected sleep in ICU were sex [0.37(0.19-0.72), p < 0.01], age and sex interaction [1.02(1.01-1.03), p < 0.01], bedside phone [0.92(0.87-0.97), p < 0.01], prior quality of sleep at home [1.30(1.05-1.62), p = 0.02], and use of steroids [0.82(0.69-0.98), p = 0.03] during the stay in ICU. CONCLUSION: Reduced sleep quality is a common problem in ICU with a multifactorial etiology.

Obstructive sleep apnea syndrome in Prader-Willi Syndrome: an unrecognized and untreated cause of cognitive and behavioral deficits?

Prader-Willi Syndrome (PWS) is a rare genetic disorder characterized by a range of physical, psychological, and physiological abnormalities. It is also distinguished by the high prevalence of obstructive sleep apnea syndrome (OSAS), i.e., repetitive upper airway collapse during sleep resulting in hypoxia and sleep fragmentation. In non-PWS populations, OSAS is associated with a range of neurocognitive and psychosocial deficits. Importantly, these deficits are at least partly reversible following treatment. Given the findings in non-PWS populations, it is possible that OSAS may contribute to neurocognitive and psychosocial deficits in PWS. The present review examines this possibility. While acknowledging a primary contribution from the primary genetic abnormality to central neural dysfunction in PWS, we conclude that OSAS may be an important secondary contributing factor to reduced neurocognitive and psychosocial performance. Treatment of OSAS may have potential benefits in improving neurocognitive performance and behavior in PWS, but this awaits confirmatory investigation.