Sleep is related to physical function and emotional well-being after cardiac surgery

Background. Emotional well-being and physical function are important quality-of-life outcomes after cardiac surgery. Alterations in sleep patterns, including sleep deprivation and altered circadian patterning, also are common. The relations among sleep pattern alterations, physical function, and emotional well-being are not well understood. Objective: This study aimed to examine the relations of sleep patterns to physical function and emotional well-being 4 and 8 weeks after cardiac surgery. Methods: Cardiac surgery patients (n = 72) wore wrist actigraphs and completed sleep diaries for 3 days during postoperative weeks 4 and 8. They also completed the Epworth Sleepiness Scale, the Pittsburgh Sleep Quality Index, and the Medical Outcomes Survey Short Form 36 preoperatively and at postoperative weeks 4 and 8. Pearson correlations and hierarchical multiple regression analysis were used to analyze the data. Results: Mean sleep efficiency was 71% at 4 weeks and 74% at 8 weeks, as measured with wrist actigraphy. According to participants' self-report, 64% experienced sleep disturbance at 4 weeks and 47% at 8 weeks. Sleep pattern variables, including sleep efficiency and self-reported sleep quality, explained 16% of the variance in physical function at 4 weeks. Self-reported sleep quality explained 8% of the variance in physical function at 8 weeks as well as 12% of the variance in emotional well-being at postoperative week 4 and 13% of the variance at postoperative week 8, after control was used for the contributions of baseline physical function, emotional well-being, age, and sex. Conclusions: The results suggest that sleep contributes to both physical functional and emotional well-being 4 and 8 weeks after cardiac surgery.