People with Parkinson’s disease at increased risk for suicide

Individuals with Parkinson’s disease were at increased risk for suicide, according to results of a nationwide population-based cohort study published in JAMA Psychiatry.

“Research into the association between [Parkinson’s disease] and suicide has not provided a consistent picture,” Ying-Yeh Chen, MD, ScD, of the Taipei City Psychiatric Center in Taiwan, and colleagues wrote. “Several studies have found high suicide rates in patients with [Parkinson’s disease], whereas others have not, and [one] study has shown a considerably lower risk than in the general population. Given that suicide is a rare occurrence, studies with large and representative population-based [Parkinson’s disease] samples are needed to reach a reliable estimate of suicide rates.”

The investigators analyzed data of 35,891 patients with Parkinson’s disease, linking data from Taiwan’s National Health Insurance data set and the Taiwan Death Registry across 14 years. They randomly selected by risk set sampling and matched four control participants from the general population to each affected individual according to age, sex and residence, for a total of 143,557 control participants. Parkinson’s disease diagnosis retrieved from the National Health Insurance data set served as the exposure. Main outcomes and measures included suicide recorded in the Taiwan Death Registry, and Cox proportional models and hazard ratios used to assess the link between Parkinson’s disease and the risk for suicide over the follow-up period.

Results showed 151 individuals with Parkinson’s disease and 300 control participants died by suicide. Those with Parkinson’s disease had higher risk (HR = 2.1; 95% CI, 1.7-2.5) for suicide than control participants, after adjustments for markers of dementia, socioeconomic position and medical comorbidities. The association between Parkinson’s disease and suicide risk remained (HR = 1.9; 95% CI, 1.6-2.3) after controlling for mental disorders. Those who died by suicide in the Parkinson’s disease group were slightly younger and more likely to be urban dwelling, have mental disorders and adopt jumping as a method of suicide compared with control participants.

“Over and above identifying and treating mental disorders in [Parkinson’s disease], integrating mental health care into primary care, geriatric health care and [Parkinson’s disease] specialty care might be helpful. Furthermore, socioenvironmental interventions, such as enhancing family and community connectedness and home safety assessment to prevent suicide by jumping, are all potential intervention measures.”