Healthcare utilization, costs, and productivity losses in treatment-resistant depression in Finland – a matched cohort study

BACKGROUND: Due to its relatively high prevalence and recurrent nature, depression causes a major burden on healthcare systems, societies and individuals. Our objective was to investigate healthcare resource utilization and costs associated with treatment-resistant depression (TRD) compared with non-treatment-resistant depression in Finland. METHODS: Of all patients aged 16–65 years and diagnosed with depression in Finland during 2004–2016, persons with TRD (N = 15,405) were identified from nationwide registers and matched 1:1 with comparison persons with depression who initiated antidepressant use but did not have TRD at the time of matching. TRD was defined as initiation of a third treatment trial after having failed two pharmacological treatment trials. Follow-up period covered 5 years after TRD or corresponding matching date (until end of 2018). Health care resource utilization was studied with negative binomial regression and costs of TRD (per patient per year) with generalized estimating equations, by adjusting for baseline costs, comorbidity and baseline severity of depression. RESULTS: Persons with TRD (mean age 38.7, SD 13.1, 60.0% women) had more health care utilization and work disability (sick leaves and disability pensions), adjusted incidence rate ratio for work disability days was 1.72 (95% CI 1.64–1.80). This resulted in 1.9-fold higher total costs for persons with TRD (15,907 versus 8335 EUR), adjusted mean difference 7572 (95% CI 7215–7929) EUR per patient per year, higher productivity losses (due to sick leaves and disability pensions, mean difference 5296, 95% CI 5042–5550), and direct healthcare costs (2003, 95% CI 1853–2151) compared with non-TRD patients. Mean difference was the highest during the first year after TRD (total costs difference 11,760, 95% CI 11,314–12,206) and the difference decreased gradually after that. CONCLUSION: Treatment-resistant depression is associated with about two-fold cost burden compared with non-treatment-resistant depression. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12888-022-04115-7.