Clinical Summary
Clinical Summary: The Role of Chronic Anhedonia in the Relationship Between Treatment-Resistant Depression and Suicidality
Patients with treatment-resistant depression often remain symptomatic despite multiple medication trials, and many present with ongoing suicide risk that is difficult to stratify in routine care. This study highlights a practical signal clinicians can assess quickly: whether anhedonia has been present both historically and currently, not just in the past 2 weeks.
Design
This study’s cross-sectional design and reliance on self-report measures for diagnostic assessment inherently limit the conclusions that can be drawn about causality.
N
160 individuals
Population
The study included 160 individuals from the START Clinic for Mood and Anxiety Disorders in Toronto, Canada. Participants were selected based on a history of at least 1 major depressive episode. In line with the study’s hypothesis that untreated ADHD may present as TRD symptoms, individuals referred for adult ADHD treatment were excluded to prevent potential confounding effects.
Setting
the START Clinic for Mood and Anxiety Disorders in Toronto, Canada
Key Findings
- Of 160 participants, 97 (61%) participants met criteria for TRD; within the TRD cohort (N=92 after correcting for missing suicide data), 60 (65%) participants reported suicidal ideation in the month prior to assessment and 16 (17%) reported a suicide attempt within the same timeframe.
- In the TRD cohort (N=92 after correcting for missing suicide data), 84 participants (91%) reported a past episode of anhedonia, 54 participants (59%) experienced an acute episode, and 53 participants (58%) indicated chronic anhedonia.
- Among participants in the TRD group, 65% of participants with chronic anhedonia reported suicidal ideation, compared with only 44% of their TRD counterparts with past or acute anhedonia; this difference was statistically significant (χ2 [1, N =97]=3.86, P= .049, Φ =.205).
- Participants in the TRD group with chronic anhedonia were 2.4-fold more likely to report suicidal ideation than participants in the TRD group without chronic anhedonia (ie, acute or past anhedonia).
- Participants in the TRD group with chronic anhedonia were significantly more likely to report a suicide attempt (χ2 [1, N=97]=4.43, P=.035, Φ =.220) and were 3.9-fold more likely to attempt suicide in the month prior to assessment via MINI than those without chronic anhedonia.
Clinical Bottom Line
In treatment-resistant depression, chronic anhedonia marks a higher-risk subgroup for both suicidal ideation and recent suicide attempt. Asking whether anhedonia has been present both historically and currently can improve suicide risk assessment beyond noting anhedonia alone.
Practice Implications
- When evaluating treatment-resistant depression, assess the persistence of anhedonia, not just its current presence; the study defined chronic anhedonia by endorsement of both historical and current anhedonia on MINI items A2a and A2b.
- Prioritize closer suicide monitoring in patients with treatment-resistant depression who report chronic anhedonia, given the 2.4-fold greater likelihood of suicidal ideation and 3.9-fold greater likelihood of suicide attempt.
- Interpret any anhedonia cautiously in major depressive disorder, since 84 participants (91%) in the TRD cohort endorsed past anhedonia; the clinically useful distinction here was chronic anhedonia versus past-only or acute-only anhedonia.
- Consider structured suicide assessment tools in this population; the article notes that validated tools such as the Sheehan Suicidality Tracking Scale, combined with more frequent follow-up, may aid early identification and intervention.
