Sleep duration in the 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.

Aim: The aims of this study were:

(1) to describe the clinical characteristic of ST-elevation myocardial infarction (STEMI) patients who sleep too little or too much; and

(2) to determine whether sleep duration is independently associated witha higher risk of all-cause mortality.

Methods: We enrolled into the study 407 consecutive patients admitted with a diagnosis of STEMI. All patients were asked for sleep duration in the first three months after being discharged from the hospital. According to the sleep duration, we divided patients into three groups: A — the reference category defined as 6–8 sleep hours, B — short sleep with < 6 h, and C — long sleep with > 8 h.

Results: The final analysis covered 379 patients (271 males; mean age 59.4 ± 10.61). 36 (9.5%) patients slept less than 6 h, 26 (6.9%) slept more than 8 h per night. The all-cause three-year mortality was 1.9% in the reference category, 13.9% in patients who slept less than 6 h, and 30.8% in patients who slept more than 8 h per night (p < 0.0001). In the multiple logistic regression analysis, short (OR 10.2, 95% CI 2.1–50, p = 0.004) and long sleep duration (OR 33.3, 95% CI 6.8–163.4, p < 0.001) were strong and independent predictors of all-cause mortality.

Conclusions: Too short and especially too long duration of sleep in the first months after myocardial infarction are strong,independent predictors of all-cause mortality.