Cost-Utility of Repetitive Transcranial Magnetic Stimulation (rTMS) among Treatment Resistant Depression Patients

Depression has a high prevalence worldwide and because of its recurrent nature, it represents a major economic burden on society. It is important to identify and evaluate effective treatments to avoid the health disutilities and costs related to poor health. Repetitive transcranial magnetic stimulation (rTMS) is a neuromodulatory technique which is clinically safe, non-invasive, and effective for major depressive disorder and it is used for treatment after at least two failed antidepressant medication trials. The availability of rTMS treatment is still limited in many countries.

The main study objective was to evaluate the cost-effectiveness of add-on rTMS therapy compared with pharmacotherapy in patients with treatment-resistant depression in Finland from a societal perspective.

A one-year Markov-model with two-month cycles was analysed to compare costs and quality adjusted life years (QALYs). Medical and productivity costs were included in the analysis. The data for the model (transition probabilities, resource utilization, utilities) were sourced from published literature, a national unit cost report, and Finnish expert opinions. Incremental cost-effectiveness ratio was calculated. Uncertainty was assessed using univariate and multivariate probabilistic sensitivity analyses and scenario analyses.

rTMS patients gained an average of 0.041 additional QALYs over one year time horizon with an incremental cost of 3,514 EUR compared to pharmacotherapy alone. The result corresponds to incremental cost-effectiveness ratio (ICER) of 85,133 EUR per QALY. Sensitivity analysis points out that one of the key parameters relating to uncertainty and driving ICER is the high unit cost of rTMS treatment.

rTMS as an add-on treatment for depression has a beneficial clinical effect compared to pharmacotherapy alone, with greater costs. However, ICER was very high suggesting that rTMS may not be cost-effective acute treatment for TRD patients in Finland. If the unit cost of the rTMS treatment can be reduced, the treatment could be cost-effective. The main limitation of this study was the short time horizon. In addition, modelling studies include assumptions, which contain uncertainty.

The cost-effectiveness of interventions depends on the health care decision-maker's willingness to pay. rTMS can be effective in treating depression; however, in high price level countries (high unit costs) with limited access to treatment, rTMS may not provide value for money for treating acute phase TRD patients, and it may not be recommended for public health care resources investments. It should be still noted that mental health conditions can be complex and have broad effects on an individual's life. When conducting economic evaluations of mental health interventions, it is important to consider productivity costs alongside direct medical costs.

Decisions and recommendations concerning allocating public funding should require economic evaluation of interventions. One method to support local decision-making can be localization and modelling studies when effectiveness data is already available.

Economic evaluation of interventions is more needed in the field of mental health to support sustainable decision-making. Long-term data is also needed to ensure those decisions.