Global trends and projections of Parkinson's disease incidence: a 30-year analysis using GBD 2021 data

Parkinson's disease (PD) is a neurodegenerative disorder marked by the progressive loss of dopaminergic neurons, leading to motor dysfunction and non-motor symptoms like cognitive decline and depression. With the aging global population, PD incidence is anticipated to rise, especially in regions with rapidly growing elderly populations. This study leverages Global Burden of Disease (GBD) 2021 data to analyze the burden of PD by region, sex, and age group, examining trends from 1992 to 2021 and projecting the future burden to 2030.

Data from the GBD 2021 database for the years 1992-2021 were analyzed to assess age-standardized incidence rates (ASIR) and mortality of PD across socio-demographic index (SDI) regions, sex, and age groups. The Age-Period-Cohort (APC) model was used to explore temporal trends, while the Bayesian Age-Period-Cohort (BAPC) model projected future PD burden from 2022 to 2030.

From 1992 to 2021, global PD cases increased from 450,000 to 1.34 million, with crude incidence rates rising from 8.19 to 16.92 per 100,000 and ASIR from 11.54 to 15.63 per 100,000, indicating an annual net drift of 1.11% (95% CI 1.06%-1.17%), reflecting a growing burden driven by an aging population. All SDI regions saw a growth in PD burden, with the highest increases in middle- and high-middle-SDI regions, where male incidence was notably higher than female. Incidence rates escalated sharply in individuals aged 60 and older, peaking in those aged 85 and above. Projections suggest that by 2030, global PD cases will reach 1.93 million, with an ASIR of 27 per 100,000.

The findings highlight a sustained global increase in PD burden, particularly in middle- and high-income regions and among men. In low-SDI areas, PD burden may be underestimated due to limited healthcare access and diagnostic challenges. These results stress the urgent need for health policies focused on elderly populations, especially men, and call for effective prevention and intervention strategies to mitigate the future impact of PD.