A Popular Sleep Med Linked to Arrhythmia
REVIEW OF: Chen HJ et al, J Chin Med Assoc 2026
STUDY TYPE: Population-based matched cohort study
EVIDENCE GRADE: Low (4/10)
This study looked at new cardiac arrhythmias over an average of 15 years in a large data base from Taiwan. They matched 152,652 new zolpidem (Ambien) users to 305,304 controls, matching for age, sex, and index year. Those who had prior arrhythmia or heart failure were excluded.
Zolpidem users had nearly twice the rate of arrhythmia compared to controls (adjusted hazard ratio, aHR, 1.98). The strongest associations were with paroxysmal tachycardia (aHR 2.57), atrial flutter (aHR 2.49), atrial fibrillation (aHR 1.99), and cardiac arrest (aHR 2.22). The risk held up across sex, age groups, and when stratified by medical disorders. Patients on two or more drugs in the zolpidem class (Z-drugs) had a higher risk than those on zolpidem alone (aHR 2.46 vs 1.39). Zolpidem was not linked to sinus node dysfunction or premature beats.
This is a well-powered observational study, and the associations are consistent and biologically plausible — zolpidem inhibits hERG potassium channels, which can prolong QTc and promote re-entry tachyarrhythmias. That said, causality can’t be established here, and the dataset lacked dosing data, adherence information, and lifestyle factors.
Rather than the sleep medicine, it could be the insomnia itself that contributes to arrhythmia risk. Still, a near-doubling in arrhythmia hazard is hard to dismiss.
Practice Implications
- For patients with pre-existing cardiac risk — especially those with hypertension, ischemic heart disease, or a history of atrial flutter — it’s worth asking whether zolpidem is really the best choice, and whether therapy (CBT-insomnia) or alternative agents have been adequately considered.
—Chris Aiken, MD
Director, Psych Partners
Editor in Chief, Carlat Psychiatry Report
