Background: Independently, veterans and individuals with Parkinson's Disease (PD) are at increased risk for suicide. To our knowledge, the risk of suicide among veterans with PD has yet to be evaluated. This study aimed to examine the associations between PD and risk of suicide, as well as suicide means among those using Veteran Health Administration (VHA) services.
Methods: Retrospective cohort study of individuals who used VHA services between 1/1/2001-12/31/2019. Cox proportional hazard models were used to estimate the hazard of suicide for those with PD relative to those without. A nested-case control study was carried out among the suicide decedents where logistic regression was used to assess the relationship between PD and suicide by firearms versus suicide by any other means.
Results: The unadjusted hazard of death by suicide for those with a PD diagnosis, relative to those without, was 1.51 (95% CI: 1.32-1.72, p < 0.0001), and was still significant after controlling for age/gender, and psychiatric/chronic physical health diagnoses (HR: 1.50; 95% CI: 1.32-1.72, p < 0.0001; HR:1.21, 95% CI:1.06-1.38, p = 0.006, respectively). Compared to the non-PD cohort, the PD group also had higher rates of mood, anxiety, and psychotic disorders. There was no significant difference between the method of suicide for those with PD versus those without PD (p = 0.60). Most suicide deaths among both cohorts were firearm-related (PD = 78.9%, No-PD = 80.3%).
Conclusions: PD is associated with an elevated risk for suicide. Based on the high rate of deaths by firearm, increased efforts to facilitate lethal means safety among veterans is warranted.
Published by Elsevier Ltd.