Evaluating Whether Melatonin Impacts Postoperative Sleep Following Total Joint Arthroplasty: A Systematic Review and Meta-analysis of Randomized Controlled Trials

Melatonin is a commonly used sleep aid, though its effects on postoperative sleep after total joint arthroplasty (TJA) remain unclear. Therefore, the objective of this study was to evaluate the effect of melatonin on subjective and objective sleep measures of postoperative sleep after TJA. The primary outcome of interest was the Pittsburgh Sleep Quality Index (PSQI). A search was performed utilizing the Boolean search phrase “(melatonin OR ramelteon OR tasimelteon OR agomelatine) AND (joint OR hip OR knee) AND (replacement OR arthroplasty).” Sleep duration, nightly awakenings, and patient-reported sleep outcomes were recorded when available. PSQI scores at six weeks were compared with a random-effects proportion meta-analysis weighted for individual study size. Across the 4 included randomized controlled trials, 455 patients were identified, of whom 227 received melatonin, and 228 received a placebo. Melatonin dosage was 5 mg in three studies and 6 mg in one. Across the four studies, melatonin did not significantly impact subjective or objective sleep outcomes. Meta-analysis of 6-week postoperative PSQI scores of 144 patients demonstrated no significant differences compared to 146 control patients (P = 0.74). Melatonin does not appear to have a significant impact on postoperative sleep following TJA. Further investigation is warranted to address other factors, such as pain and environmental disturbances, to improve sleep quality.