Treatment-resistant depression and risk of all-cause mortality and suicidality in Danish patients with major depression

• Published in: Journal of psychiatric research Vol. 135; pp. 197 - 202
• Main Authors: Gronemann, Frederikke Hørdam, Jørgensen, Martin Balslev, Nordentoft, Merete, Andersen, Per Kragh, Osler, Merete
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.03.2021
• Subjects: Denmark - epidemiology; Depression; Depressive Disorder, Major - drug therapy; Depressive Disorder, Major - epidemiology; Depressive Disorder, Treatment-Resistant; Humans; Major depressive disorder; Mortality; Risk Factors; Self-harm; Suicide; Treatment-resistant depression; Denmark; Suicide; Self-harm; Mortality; Major depressive disorder; Treatment-resistant depression
• ISSN: 0022-3956; 1879-1379; 1879-1379
• DOI: 10.1016/j.jpsychires.2021.01.014

Treatment-resistant depression (TRD) has been associated with higher mortality and risk of suicide, but this has mainly been showed in few studies which did not include self-harm. The aim was to investigate the association of TRD with all-cause mortality, suicide and self-harm in a nationwide cohort of patients with major depression and explore any differences in relation to patient characteristics. First-time hospital contacts for major depression between January 1, 1996 and December 31, 2014 were identified in Danish patient registers (ICD-10: F32 and F33). TRD was defined as two shifts in antidepressant treatment, assessed from one year prior depression diagnosis until one year after. Information on mortality, suicide and self-harm was obtained from Danish registers and associations between TRD and the three prognostic outcomes were analyzed using Cox Proportional Hazard Regression. TRD was not associated with all-cause mortality the first year of follow-up (adjusted HR (aHR) 1.04, 95% confidence interval (CI) [0.98–1.11]), and the HR for mortality was lower the following 1–5 years. However, TRD was associated with higher rates of suicide (0–1 year: aHR 2.20, 95% CI [1.77–2.74]; 1–5 years: aHR 1.70, 95% CI [1.42–2.03]) and self-harming behavior (0–1 year: aHR 1.51, 95% CI [1.36–1.66]; 1–5 years: aHR 1.59, 95% CI [1.48–1.70]). The above risk estimates varied only slightly across sociodemographic and clinical patient characteristics. Patients with TRD have higher rates of suicide and self-harm compared with non-TRD patients, whereas there seems to be no increase overall in all-cause mortality – in fact, there was a lower rate at follow-up after 1 year. We found only a few differences in HRs for mortality or suicidality across patient characteristics. •Treatment-resistant depression (TRD) is not associated with all-cause mortality during 5 years of follow-up.•TRD is associated with higher rates of suicide and self-harm during 5 years of follow-up.•These associations vary only slightly across sociodemographic and clinical patient characteristics.•Women and those with mild depression posed higher relative rates of suicidality.