Melatonin and Multivitamin Use in Sleep Disturbance Populations: Associations with Health Outcomes and Mortality from a National Cohort Study

Background Comprehensive health benefits and risks of melatonin remain scarce. This study aims to evaluate the association between melatonin use and health outcomes, as well as its comparative effectiveness against multivitamins. Methods In total, 7,717 adults experiencing sleep disturbances with dietary supplements data were enrolled from the 2005–2018 National Health and Nutrition Examination Survey (NHANES). Multivariable Cox regression analysis was employed to investigate the associations of melatonin and multivitamin supplementation with all-cause and cardiovascular mortality. Results Melatonin and multivitamin users had longer sleep durations than non-users (melatonin: t = 2.68, P < 0.001; multivitamins: t = 5.44, P < 0.001). Only multivitamin users showed fewer depressive symptoms (t = -7.00, P < 0.001), while melatonin users did not. Melatonin users (odds ratio [OR], 0.44; 95% CI: 0.20–0.86; P = 0.024) and multivitamin users (OR, 0.79; 95% CI: 0.69–0.91; P = 0.001) had lower odds of short sleep. After adjustments, melatonin users faced a higher risk of cardiovascular mortality (hazard ratio [HR], 3.46; 95% CI, 1.01 to 11.82; P = 0.048), whereas multivitamin users had lower risks of all-cause mortality (HR, 0.84; 95% CI, 0.71 to 0.99; P = 0.040) and cardiovascular mortality (HR, 0.61; 95% CI, 0.39 to 0.95; P = 0.027). Conclusions Melatonin does not appear to be the sole selection for early-stage sleep disturbances; multivitamins might constitute a more judicious alternative, associated with better sleep duration and overall health outcomes. Further studies are required to confirm these findings.