Long-term Risks of Depression and Suicide Among Men with Prostate Cancer: A National Cohort Study

Background: A diagnosis of prostate cancer (PC) may cause psychosocial distress that worsens quality of life; however, long-term mental health outcomes are unclear. Objective: To determine the long-term risks of major depression and death by suicide in a large population-based cohort. Design, setting, and participants: This was a national cohort study of 180 189 men diagnosed with PC during 1998–2017 and 1 801 890 age-matched, population-based, control men in Sweden. Outcome measurements and statistical analysis: Major depression and death by suicide were ascertained from nationwide outpatient, inpatient, and death records up to 2018. Cox regression was used to compute hazard ratios (HRs) adjusted for sociodemographic factors and comorbidities. Subanalyses assessed differences by PC treatment during 2005–2017. Results and limitations: Men diagnosed with high-risk PC had higher relative rates of major depression (adjusted HR [aHR] 1.82, 95% confidence interval [CI] 1.75–1.89) and death by suicide (aHR 2.43, 95% CI 2.01–2.95). These associations persisted for ≥10 yr after PC diagnosis. The relative increase in major depression was lower among those treated with radiation (aHR 1.44, 95% CI 1.31–1.57) or surgery (aHR 1.60, 95% CI 1.31–1.95) in comparison to androgen deprivation therapy (ADT) alone (aHR 2.02, 95% CI 1.89–2.16), whereas the relative rate of suicide death was higher only among those treated solely with ADT (aHR 2.83, 95% CI 1.80–4.43). By contrast, men with low- or intermediate-risk PC had a modestly higher relative rate of major depression (aHR 1.19, 95% CI 1.16–1.23) and higher relative rate of suicide death at 3–12 mo after PC diagnosis (aHR 1.88, 95% CI 1.11–3.18) but not across the entire follow-up period (aHR 1.02, 95% CI 0.84–1.25). This study was limited to Sweden and will need replication in other populations. Conclusions: In this large cohort, high-risk PC was associated with substantially higher relative rates of major depression and death by suicide, which persisted for ≥10 yr after PC diagnosis. PC survivors need close follow-up for timely detection and treatment of psychosocial distress. Patient summary: In a large Swedish population, men with aggressive prostate cancer had higher long-term relative rates of depression and suicide.