[WITHDRAWN] Health Conditions and Risk of Suicide Among Adults Aged 55 and Older

Background and Purpose: According to the CDC, suicide was the 12^th leading cause of death in the U.S. in 2020. Although the age-adjusted suicide rate decreased between 2018 and 2020, rates for men 75+ remain high. The Surgeon General’s 2021 Call to Action on Suicide Prevention identifies older adults as a high-risk group for suicide and calls for increased understanding of risk factors risk.

Methods: This case-control study examines health conditions as risk factors for suicide death among adults aged 55+ adjusting for mental health or substance use diagnoses. Using data from nine healthcare systems affiliated with the Mental Health Research Network, 1,327 patients aged 55 and older who died by suicide between 2000 and 2015 were matched with controls in a 1:10 ratio using propensity score matching method. A total of 14,597 patients were included in this study. Suicide deaths were identified using ICD-10 codes from official government mortality records matched with health system records. Diagnoses within the year prior to the index date were identified by ICD-9 codes and included mental health and substance use, nineteen physical health conditions, and Alzheimer’s Disease and other dementias. Demographic information on age, sex, neighborhood income, and education were included. Descriptive statistics were used to characterize the sample by case and control groups. Conditional logistic regression models were used to estimate the unadjusted and adjusted odds of suicide associated with each diagnosis as well as the odds of suicide for individuals with zero, one, or two or more of the 20 health conditions. All adjusted models controlled for age and sex, then mental health and substance use diagnoses.

Results: Overall, among adults aged 55 and older a higher proportion who died by suicide were aged 76 or older (29.3%) and male (80%) compared to controls (19.1% and 46% respectively). Sixteen conditions were associated with suicide in unadjusted models. Eight conditions remained associated with suicide in adjusted models. The two most common conditions – hypertension and back pain – were both moderately associated with suicide. Sleep disorder and epilepsy also had strong associations with suicide, but while epilepsy was uncommon in both groups, 23.5% of those who died by suicide were diagnosed with sleep disorder compared with 8% of controls. Over half (57.9%) of those who died by suicide had two or more conditions compared to 35.9% of controls. Having two or more diagnosed conditions was associated with an increased risk for suicide (AOR=1.65, p<.001).

Conclusions and Implications: The co-occurrence of mental health and substance use diagnoses attenuated all associations, however eight conditions remained significant. Furthermore, over three-quarters (78.4%) of adults aged 55 and older who died by suicide had a diagnosis of at least one of these conditions in the year before their death compared with 62% of the control group. Findings suggest the importance of suicide prevention efforts across all healthcare settings.