Overview
- The analysis drew on five years of TriNetX electronic health records for 130,828 adults with chronic insomnia, including about 65,414 with documented melatonin use for at least 12 months.
- Long-term users had higher five-year rates of incident heart failure (4.6% vs. 2.7%), hospitalization for heart failure (19.0% vs. 6.6%), and all-cause death (7.8% vs. 4.3%) compared with matched non-users.
- Researchers emphasized the findings are associative, with key limitations such as likely misclassification of over-the-counter use, missing data on insomnia severity and psychiatric comorbidities, and a retrospective design.
- A sensitivity analysis requiring at least two melatonin prescriptions 90 days apart produced similar elevated risks, reinforcing the observed signal in documented users.
- The results were released ahead of presentation at the American Heart Association Scientific Sessions in New Orleans on Nov. 7–10, as clinicians highlight variable supplement dosing and advise patient–doctor discussion for long-term use.