25-year trends in first-time hospitalizations for Parkinson's disease and subsequent mortality: A Danish nationwide cohort study

Background: In most countries, incidence and mortality for Parkinson's disease (PD) have not been monitored by surveillance registries, although it could demonstrate the need for primary and tertiary prevention.

Objective: To examine 25-year trends in first-time hospitalizations for PD in Denmark and subsequent short and long-term mortality.

Methods: In a nationwide population-based cohort we identified all 34,947 individuals with a first-time hospitalization for PD from 1995 through 2019. We calculated standardized incidence rates of PD and 1-year and 5-year mortality by sex. Mortality rates were compared with a reference cohort randomly selected from the background population matched on sex, age, and index date.

Results: The annual standardized incidence rate of PD was relatively stable during the study period in both men and women. The incidence of PD was higher in men than in women and with the highest incidence in those aged 70-79 years. One and 5-year mortality risk after first-time hospitalization for PD was similar for men and women, and decreased by around 30% and 20%, respectively, between 1995 and 2019. The matched reference cohort had a similar decline in mortality over time.

Conclusion: The rate of first-time hospitalization for PD was relatively stable between 1995 and 2019, whereas subsequent short and long-term mortality declined during the period as in the reference cohort.