The Cost Effectiveness of Treatment Strategies for Depression in Ethiopia: A Multiple Cohort Markov Model Analysis

This study aimed to evaluate the cost effectiveness of delivering treatment interventions for major depression among Ethiopian adults aged 18-64 years.

A multiple cohort Markov model was developed to simulate how population cohorts move between three health states over time: healthy, depression and dead. Three drug interventions (tricyclic antidepressants [TCAs], selective serotonin reuptake inhibitors [SSRIs] and serotonin norepinephrine reuptake inhibitors [SNRIs]), one non-pharmacological therapy (psychotherapy) and one combination therapy (drug plus psychotherapy) were compared to a common comparator, a partial null scenario. We modelled interventions for Ethiopians aged 18-64 years with major depression in 2021 (n = 2,431,898). The study employed a cost-utility analysis framework to estimate the incremental cost-effectiveness ratios (ICERs), expressed as a cost per quality-adjusted life year (QALY). The model was run over a 10-year period, adopted a health sector perspective to estimate population-level costs and benefits with a 3% annual discount rate. Uncertainty analysis was conducted using a Monte Carlo simulation with 3000 iterations.

Psychotherapy was associated with incremental cost of US$17million (M) (95% CI US$9M-US$26M) and QALY gains of 11,857 (95% CI 125-35,227). In comparison, antidepressants, such as SNRIs, had a higher cost of US$236M (95% confidence interval [CI] US$132M-US$353M) with QALY gains of 15,369 (95% CI - 304 to 50,059). Combination therapy was associated with the highest health benefit (40,755 QALYs [95% CI - 210 to 124,928]) and incurred an incremental cost of US$162M (95% CI US$89M-US$244M). The ICER for psychotherapy was US$1,419 per QALY gained (95% CI US$344-US$22,433/QALY), suggesting cost effectiveness when adopting a one-times GDP per capita per QALY threshold. In contrast, combination therapy had an ICER of US$3,973/QALY (95% CI dominated to $63,677/QALY) and may be an appropriate option for individuals requiring both pharmacotherapy and psychotherapy. Conversely, drug therapies did not appear to be cost effective.

Psychotherapy appears to be a cost-effective intervention in Ethiopia, while combination therapy may be an alternative cost-effective option. However, access to psychotherapy and combination therapy in Ethiopia is currently restricted to hospitals and the private sector, largely due to a shortage of trained professionals such as clinical psychologists. To address this gap, policymakers should explore cost-effective strategies to expand the availability of psychotherapy services.