Does Melatonin Improve Sleep Following Primary Total Hip Arthroplasty? A Randomized, Double-Blind, Placebo-Controlled Trial.

Abstract

Sleep impairment following total hip arthroplasty (THA) is common and may decrease patient satisfaction and early recovery. Standardized postoperative recommendations for sleep disturbance (SD) have not been established. We aimed to assess whether melatonin use improves sleep quality and quantity in the acute period following THA. Patients undergoing primary, elective THA between July 2021 and March 2024 were prospectively enrolled and randomized to receive either 5 mg of melatonin or a placebo nightly for 14 days postoperatively. Participants recorded nightly pain scores on the visual analog scale, the number of hours slept, and the number of nighttime awakenings in a sleep diary. SD was assessed preoperatively and on postoperative day (POD) 14 using the patient-reported outcome measurement information system SD form. Epworth Sleepiness Scores (ESS) were collected to assess sleep quality. Of the 139 patients who completed the study protocol, there were 64 patients in the placebo group and 75 patients in the melatonin group. Both groups demonstrated comparable postoperative ESS (melatonin: 6.0 ± 4.0; placebo: 6.8 ± 4.5, P = 0.35). Melatonin patients experienced significantly more hours slept on POD two (6.5 ± 1.7; 5.7 ± 2.4, P = 0.017) and averaged over POD one to three (6.1 ± 1.6; 5.7 ± 2.0, P = 0.14), although this was not statistically significant. Fewer nighttime awakenings in the melatonin group were observed on POD 2 (2.7 ± 1.5; 3.1 ± 2.0, P = 0.28), although this was not statistically significant. The melatonin group demonstrated significantly lower postoperative patient-reported outcome measurement information system SD scores (52.5 ± 9.3; 56.3 ± 9.2, P = 0.040). Melatonin may not improve overall postoperative sleep quality following THA as measured by the ESS. Melatonin may promote sleep duration in the POD one to three period, although potential benefits wane after POD three. Melatonin is safe and can be considered for THA patients experiencing early postoperative SD. I.