Abstract 11020: Sleep Duration in First Months After ST-elevation Myocardial Infarction -- An Independent Predictor of All-cause Mortality

Abstract

Background: Sleep duration and sleep quality affect patients’ general condition and self-reported health status. The aim of this study was:(1)to describe the clinical characteristic of ST-elevation myocardial infarction patients who sleep too little or too much;(2)to determine if sleep duration is independently associated with higher risk of all-cause mortality.

Methods: 407 consecutive patients (271 males) admitted with diagnosis of ST-elevation myocardial infarction were enrolled. All patients were asked for sleep duration in first 3 months after discharged from the hospital. 28 patients were lost of follow-up. The primary endpoint was all-cause mortality. Sleep duration was assessed by asking the study participants to give the habitual night sleep time: How many hours do you sleep usually each night? According to the sleep duration, we divided patients into 3 groups:A) the reference category was defined as 6-8 sleep hours per night, B) short sleep was defined as <6 hours per night and C) long sleep was defined as >8 hours per night.

Results: After excluding patients who were lost to follow up, the final analysis covered 379 patients [271 males; mean age 59.4±10.61]. 36 (9.5%) patients slept less than 6 hours, 26 (6.9%) slept more than 8 hours per night. Patients with sleep disturbances were older (62.7±10.2 vs 58.7±10.6 years;p=0.006), had often history of myocardial infarction (25.8 vs 11.9%;p=0.03), stroke (12.9 vs 2.8%;p=0.001) and coronary artery bypass grafting (6.5 vs 1.3%;p=0.03) compared to the patients without. There was a statistically significant increase in 3 years all-cause mortality:1.9% for reference category,13.9% for patients who slept less than 6 hours, and 30.8% for patients who slept more than 8 hours per night (p value for trend<0.0001). In the multiple logistic regression analysis, short (odds ratio 10.2, 95% confidence interval 2.1-50;p=0.004) and long sleep duration (odds ratio 33.3, 95%confidence interval 6.8-163.4;p<0.001) were strong and independent predictors of all-cause mortality.

Conclusion: Short and long duration of sleep in first months after myocardial infarction are strong, independent predictors of developing all-cause mortality. The relationship between sleep duration and all-cause mortality is U-shaped.