Sleep disturbances and sleep disorders as risk factors for chronic postsurgical pain: A systematic review and meta-analysis

This systematic review and meta-analysis aimed at evaluating the role of sleep disturbances and sleep disorders in influencing presence and intensity of chronic postsurgical pain (CPSP). We included cohort studies which enrolled adults, assessed sleep disturbances or disorders before surgery, measured pain intensity, presence of pain, or opioid use at least three months after surgery. Eighteen studies were included in a narrative synthesis and 12 in a meta-analysis. Sleep disturbances and disorders were significantly related to CPSP, with a small effect size, r = 0. 13 (95% CI 0. 06-0. 20). The certainty of evidence was rated low due to risk of bias and heterogeneity. In subgroup analyses the above association was significant in studies that used pain intensity as the outcome, but not in those that used presence of pain; in studies on patients who underwent total knee arthroplasty or other surgeries, but not in those on patients who had breast cancer surgery or total hip arthroplasty; in the single study that assessed insomnia and in studies that assessed sleep disturbances as predictors. A meta-regression showed that the follow-up length was positively associated with the overall estimate. Our findings suggest that presurgical sleep disturbances and disorders should be evaluated to detect patients at risk for CPSP. Registration: https: //www. crd. york. ac. uk/PROSPERO/displayᵣecord. php? RecordID=272654.