Patterns and predictors of sleep pattern disturbance after cardiac surgery.

The purposes of this study were to examine changes in sleep patterns after cardiac surgery and the contributions of preoperative sleep to postoperative sleep. Seventy-two cardiac surgery patients wore wrist actigraphs for 3 days during the preoperative period (T1) and the 1st (T2), 4th (T3), and 8th (T4) postoperative weeks. They completed the Pittsburgh Sleep Quality Index at T1, T3, and T4. Sleep was most disturbed during the 1st postoperative week and improved at T3 and T4. Overall, sleep pattern disturbance was higher at T3 and T4 than at T1. Age, gender, preoperative New York Heart Association Functional Class, and preoperative sleep variables explained 20%-50% of the variance in sleep at T2, T3, and T4. Sleep disturbance is present preoperatively and continues during the postoperative period.