To evaluate national trends in Parkinson’s disease–related mortality among U.S. adults aged ≥65 years with psychiatric, behavioral, and neurodevelopmental comorbidities from 1999–2023.

Parkinson’s disease (PD) is a major neurodegenerative disorder frequently accompanied by psychiatric comorbidities. Despite diagnostic and therapeutic advances, mortality involving PD and psychiatric disorders among older adults remains underexplored. This study analyzes temporal trends in PD-related mortality among U.S. individuals with psychiatric disorders.

CDC WONDER data from 1999–2023 were analyzed to study deaths among adults aged ≥65 years with both Parkinson’s disease (PD; ICD-10: G20) and psychiatric disorders (ICD-10: F01–F99). Age-adjusted mortality rates (AAMRs) per 1,000,000 population were calculated using the 2000 U.S. standard population. Trends were analyzed using Joinpoint regression to estimate annual percent change (APC) and ARIMA models were applied for forecasting.

From 1999 to 2023, there were 264,770 deaths involving both Parkinson’s disease (PD) and psychiatric disorders in adults aged 65 and older. ARIMA forecasting projected the AAMR  to 172.6  (95% CI: 116.7-426.4) by 2035 (ADF p = 0.20, Box-Ljung test p = 0.61). Mortality rates were higher in men than in women (AAMR: 355.7 vs. 171.3). Substance use-related deaths were more frequent(10.4%). Whites had the highest AAMR: 260.3, while Asian or Pacific Islanders had the lowest (124.7). The Midwest and rural areas showed the highest rates(284.2 and 278.9). People aged 75–84 years had the most deaths (117,870). Among states, Kentucky had the highest state-level burden (AAMR:549.7).

Mortality involving PD and psychiatric disorders has steadily increased, disproportionately affecting men, White individuals, and residents of rural and Midwestern regions. Integrated neuropsychiatric care, early mental health screening, and equitable neurological access are essential to curb this growing burden.