Obstructive Sleep Apnea and Cardiovascular Events After Percutaneous Coronary Intervention.

BACKGROUND: There is a paucity of data from large cohort studies examining the prognostic significance of obstructive sleep apnea (OSA) in patients with coronary artery disease. We hypothesized that OSA predicts subsequent major adverse cardiac and cerebrovascular events (MACCEs) in patients undergoing percutaneous coronary intervention. METHODS AND RESULTS: The Sleep and Stent Study was a prospective, multicenter registry of patients successfully treated with percutaneous coronary intervention in 5 countries. Between December 2011 and April 2014, 1748 eligible patients were prospectively enrolled. The 1311 patients who completed a sleep study within 7 days of percutaneous coronary intervention formed the cohort for this analysis. Drug-eluting stents were used in 80.1% and bioresorbable vascular scaffolds in 6.3% of the patients, and OSA, defined as an apnea-hypopnea index of ≥15 events per hour, was found in 45.3%. MACCEs, a composite of cardiovascular mortality, nonfatal myocardial infarction, nonfatal stroke, and unplanned revascularization, occurred in 141 patients during the median follow-up of 1.9 years (interquartile range, 0.8 years). The crude incidence of an MACCEs was higher in the OSA than the non-OSA group (3-year estimate, 18.9% versus 14.0%; p=0.001). Multivariate Cox regression analysis indicated that OSA was a predictor of MACCEs, with an adjusted hazard ratio of 1.57 (95% confidence interval, 1.10-2.24; P=0.013), independently of age, sex, ethnicity, body mass index, diabetes mellitus, and hypertension. CONCLUSIONS: OSA is independently associated with subsequent MACCEs in patients undergoing percutaneous coronary intervention. Evaluation of therapeutic approaches to mitigate OSA-associated risk is warranted. CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01306526.

Optimal Body Mass Index Cut-offs for Identification of Patients with Coronary Artery Disease at High Risk of Obstructive Sleep Apnoea.

BACKGROUND: We sought to evaluate the relationship between Body Mass Index (BMI) and obstructive sleep apnoea (OSA) in Chinese patients hospitalised with coronary artery disease, and to determine the optimal BMI cut-off for prediction of OSA. METHODS: Consecutive Chinese patients who were hospitalised with symptomatic coronary artery disease were recruited to undergo an in-hospital sleep study. RESULTS: A total of 587 patients were recruited. Using cut-off for Asians, 81.2% of the cohort was overweight (BMI ≥23kg/m(2)) and 31.6% was obese (≥27kg/m(2)). A total of 59.5% was diagnosed with OSA, defined as apnoea-hypopnoea index ≥15. Body mass index, hypertension and smoking were predictors of OSA. Multiple logistic regression analysis showed that BMI remains an independent predictor of OSA (odds ratio: 1.11 [95% confidence interval: 1.06 to 1.17], p<0.001) after adjusting for smoking and hypertension. Further analysis using BMI and Apnoea-Hypopnoea Index (AHI) as continuous variables showed significant correlation between BMI and AHI (Pearson's r =0.25, P<0.001). In adjusted models, optimal BMI cut-offs to screen for OSA were 27.3kg/m(2), 23.0-23.9kg/m(2), and 20kg/m(2) for patients with neither, either, or both predictors (smoking and hypertension) respectively. The area under the curve for the adjusted and unadjusted models were similar (0.6013 vs 0.6262, p=0.118). CONCLUSIONS: Body mass index represents a convenient and readily available tool for bedside identification of patients at high risk of OSA. Body mass index cut-offs to predict risks of OSA in Chinese patients with symptomatic coronary artery disease are defined in this study.

Sleep behaviour in a sample of preschool children in Singapore.

INTRODUCTION: Sleep problems are common in all ages, but may be particularly acute in urban Singapore. This study aims to describe the sleep behaviour of, and to identify any sleep problems in, preschool children. MATERIALS AND METHODS: This was a cross-sectional questionnaire survey of 372 children attending local childcare centers. The questionnaire was based on the Children's Sleep Habits Questionnaire (CSHQ), a validated parent-report sleep screening questionnaire that contains 54 items identifying sleep behaviours in children. RESULTS: A total of 372 (40.0%) children participated. The mean age was 4.1 (SD 1.3) years (range, 2 to 6 years). Average total sleep duration was 10.8 hours (SD 1.1) with average night-time sleep duration of 8.5 hours (SD 0.6) and average nap duration of 1.6 hours (SD 1.0). Co-sleeping was common; 80.9% of children shared a room with someone else. The most common sleep problems were in the domains of sleep resistance and morning behaviour; namely: requiring company to fall asleep (n = 272, 73.1%), being afraid to sleep alone (n = 228, 61.6%) and diffi culty in waking up (n = 165, 44.4%). Among parents, 84.1 % (n = 313) perceived that their child's sleep duration was adequate. CONCLUSION: The duration of sleep in the Singaporean preschool population sampled is signifi cantly lower than recommended values and that of previously described Caucasian populations. Parental perception of sleep adequacy deviates from current recommendations. Given the clear relation of sleep duration with cognitive functioning, learning, and physical growth, this sleep deprivation should be addressed with parental education and opportunistic screening of sleep in well-child follow-ups.