ObjectivesMany researchers have expected pioglitazone to serve as an effective neuroprotective agent against Parkinson’s disease (PD). Therefore, we conducted this cohort study to investigate the association between pioglitazone use and PD by using a large Asian population-based dataset in Taiwan.DesignRetrospective cohort study.SettingTaiwan.Participants7906 patients with diabetes who had received pioglitazone were defined as the study cohort, and 7906 matched patients with diabetes who had not received pioglitazone were defined as the comparison cohort.Primary and secondary outcome measuresWe tracked each patient individually over a 5-year follow-up period to identify those diagnosed as having PD during this period. We performed Cox proportional hazard regression analyses to evaluate the HRs for PD between the study and comparison cohorts.ResultsThe findings indicated that among the sampled patients, PD occurred in 257 (1.63%): 119 (1.51%) pioglitazone users and 138 (1.75%) non-users. The adjusted HR for PD within the follow-up period was 0.90 (95% CI: 0.68 to 1.18) in the patients who had received pioglitazone compared with the matched patients who had not received pioglitazone. Moreover, this study revealed that pioglitazone use was not associated with PD incidence in men (HR: 1.06, 95% CI: 0.71 to 1.59) or women (HR: 0.84, 95% CI: 0.61 to 1.15).ConclusionsThis study did not find the relationship between pioglitazone use and PD incidence, regardless of sex, among an Asian population of patients with diabetes.