Mortality and causes of death in patients with Parkinson's disease in Taiwan

Background Previous studies that examined Parkinson's disease (PD) mortality were mostly conducted in Western countries. Objects We compared mortality rates and causes of death in PD patients and persons without PD from Taiwan over 15 years of follow-up. Methods Within the National Health Insurance database, we followed 50,290 incident PD patients (2003–2016) and 201,153 matched non-PD participants (controls) until 31/12/2018. We used multivariable Cox proportional-hazards regression models to compare mortality rates and causes of death in PD patients and controls. Due to non-proportionality, we performed stratification by follow-up duration (≤5/>5 years). We examined interactions between PD status participants’ characteristics for all-cause mortality. Results PD patients had higher all-cause mortality than controls (HR = 1.40, 95% CI = 1.37–1.42); the association was stronger ( p < 0.0001) after the first 5 years of follow-up (HR = 1.49 [1.46–1.53]) than before (HR = 1.34 [1.31–1.37]). The strongest associations were observed for suicide (HR = 1.79 [1.52–2.10]), dementia (HR = 1.69 [1.47–1.93]), and pneumonia (HR = 1.57 [1.49–1.65]). The association between PD and death decreased as age increased, and was stronger in patients without comorbidities, depression, and dementia than in those with. Conclusions Taiwanese PD patients have reduced life expectancy throughout the course of disease with a stronger association after the first 5 years of follow-up. PD had a stronger impact on mortality in younger persons and in those without comorbidities. Prevention of pneumonia and suicide, and appropriate management of dementia and comorbidities would help reduce PD-related mortality. Our findings may help health authorities allocate resources to improve the management of PD patients in order to address PD-related mortality.