Prevalence and Risk Factors of Cognitive Impairment in Parkinson Disease: A Population-Based Case–Control Study in Taiwan

The aim of this study was to evaluate the Parkinson disease (PD) prevalence of cognitive impairment in Taiwan. The case–control study consisted of 6177 cognitive impairment patients and 24,708 noncognitive impairment as controls for the period of 2006 to 2010 and both of the groups aged ≥50 years. The multivariable logistic regression analyses were used to estimate the odds ratio (OR) for cognitive impairment, and the 95% confidence intervals (CIs) among patients with PD were compared with those of non-PD patients. PD (adjusted odds ratio [aOR] is 3.07, 95% CI 2.76–3.41) is the one of the most contributed risk factors for cognitive impairment. Besides, we found a remarkable result of the diagnosed cognitive impairment of PD that was found highest in the first 6 months (aOR 11.98, 95% CI 8.51–16.86) and then decrease the incident year by year. The PD prevalence in a patient with cognitive impairment in our data present is 12.1% lower than those with truly dementia published previously and documented by western studies. We found a remarkable result of the diagnosed cognitive impairment of PD that was found highest in the first 6 months and then decrease the incident year by year.