The capacity to consent to treatment is altered in suicidal patients.

Background: Many patients with depression refuse treatment. Moreover, suicide attempters often display low perceived need of treatment and impaired decision-making. These observations raise questions about the capacity to treatment consent in depressed suicide attempters (SA).

Methods: In patients with current depressive episode (N = 33 SAs and N = 27 non-SAs), consent capacity was evaluated with the MacArthur Competence Assessment Tool for Treatment (MacCAT-T), insight with the Beck Cognitive Insight Scale, and depression severity with the Beck Depression Inventory (BDI).

Results: The median BDI score in the whole sample (N = 60) was 21 [10;36], and was higher in SAs than non-SAs (27 [11;36] vs. 15 [10:33], p < 0.001). Consent capacity was impaired in 30% (appreciation), 53% (reasoning) and 60% (understanding) of all patients. MacCAT-T sub-scores were lower in SAs than non-SAs (understanding: 4.4 [2.35;5.8] vs. 5.3 [3.13;6]); appreciation: 3 [1;4] vs. 4 [2;4]); reasoning (4 [1;7] vs. 7 [3;8]), and ability to express a choice: 1 [0;2] vs. 2 [0;2]; all p < 0.001). In multivariate analyses, suicide attempt history and depression severity (but not insight) were negatively associated with MacCAT-T sub-scores.

Conclusion: More research is needed on the capacity to consent to treatment of patients with depression, particularly suicidal individuals, to make informed choices about their treatment. Trial registration The Montpellier University Hospital Institutional Review Board approved the study (No. 202100714).