Mortality and cause of death in South Korean patients with Parkinson’s disease: a longitudinal follow-up study using a national sample cohort

OBJECTIVE: The incidence rate of Parkinson’s disease (PD) is growing rapidly owing to the ageing population. We investigated the mortality rates and causes of death in South Korean patients with PD. DESIGN: We investigated a national cohort using the nationwide insurance database. SETTING: Korean Health Insurance Review and Assessment Service—National Sample Cohort database. PARTICIPANTS: We included 3510 participants ≥60 years of age who were diagnosed with PD between 2002 and 2013, as well as 14 040 matched controls. INTERVENTIONS: None PRIMARY AND SECONDARY OUTCOME MEASURES: A stratified Cox proportional hazards model was used to evaluate patients with PD who were matched 1:4 with non-PD control subjects adjusted for age, sex, income and region of residence. The causes of death were grouped into 12 classifications. RESULTS: The adjusted HR for mortality in the PD group was 2.09 (95% CI 1.94 to 2.24, p<0.001). Subgroup analysis according to age (<70 years, 70–79 years, and ≥80 years) and sex revealed that patients with PD showed higher adjusted HRs for mortality across all subgroups. Mortalities caused by metabolic, mental, neurologic, circulatory, respiratory, and genitourinary diseases, as well as trauma, were more common in the PD group than in the control group, with the highest OR observed in patients with neurologic disease. CONCLUSIONS: We demonstrated that PD in South Korean patients ≥60 years of age was associated with increased mortality in both sexes regardless of age.