Despite the best available clinical care,
pain after surgery is a virtually universal patient experience that can have pervasive negative consequences. Given the large variability among patients in
postoperative pain levels, research on novel modifiable risk factors is needed. One such factor suggested by recent experimental studies indicates that disruption of even a single night's sleep can increase subsequent
pain in healthy volunteers. In this preliminary clinical study, we tested the hypothesis that poor sleep the night before surgery would predict heightened
postoperative pain. Patients (n=24) scheduled for routine breast-conserving
surgical procedures for the diagnosis or treatment of
cancer were recruited and wore an actigraphy device providing objective, validated measures of sleep duration and disruption (low sleep efficiency).
Pain severity and interference with daily activities for the week after surgery was assessed with the Brief
Pain Inventory. As hypothesized, multiple regression analyses revealed that lower sleep efficiency was a significant predictor of greater
pain severity and interference, controlling for age, race, and perioperative
analgesics as appropriate. Sleep efficiency was not significantly related to measures of depressed mood, emotional upset, or relaxation assessed on the morning of surgery. Patients with sleep efficiency in the lowest tertile had clinically higher levels of
pain (>2 points) compared with patients in the highest sleep efficiency tertile. Sleep duration had no significant effects. This preliminary clinical study supports the possibility that sleep disruption on the night before surgery may increase patients' experience of
pain after surgery. Research to investigate the mechanisms underlying these effects and to explore the possible clinical benefits of interventions to improve patients' sleep before surgery is now warranted.