Zolpidem and the risk of Parkinson's disease: A nationwide population-based study

Background: This nationwide population-based study investigated the risk of Parkinson's disease (PD) after zolpidem use in patients with sleep disturbance using the National Health Insurance Research Database (NHIRD) in Taiwan. Material and methods: In total, 59,548 adult patients newly diagnosed with sleep disturbance and who used zolpidem were recruited as the study cohort, along with 42,171 subjects who did not use zolpidem as a comparison cohort from 2002 to 2009. Each patient was monitored for 5 years, and those who subsequently had PD were identified. A Cox proportional hazards model was used to compare the risk of PD between the study and comparison cohorts after adjusting for possible confounding risk factors. Results: The patients who received zolpidem had a higher cumulative rate of PD than those who did not receive zolpidem during the 5-year follow-up period (1.2% vs. 0.5%, P <0.001). The adjusted hazard ratios were 1.10 (95% CI, 0.88-1.37), 1.41 (95% CI, 1.17-1.72), and 1.27 (95% CI, 1.05-1.55) for zolpidem use with 28-90, 91-365, and more than 365 cumulative defined daily doses (cDDDs), respectively, compared to those who did not use zolpidem. Conclusions: Among the patients with sleep disturbance, zolpidem use increased the risk of PD after 5 years of follow-up. Further mechanistic research of zolpidem effect in PD is needed. (C) 2014 Elsevier Ltd. All rights reserved.