Effects of anhedonia on health-related quality of life and functional outcomes in major depressive disorder: A systematic review and meta-analysis

Background: Major depressive disorder (MDD) is a heterogeneous group of mood disorders. A prominent symptom domain is anhedonia narrowly defined as a loss of interest and ability to experience pleasure. Anhedonia is associated with depressive symptom severity, MDD prognosis, and suicidality. We perform a systematic review and meta -analysis of extant literature investigating the effects of anhedonia on health -related quality of life (HRQoL) and functional outcomes in persons with MDD. Methods: A literature search was conducted on PubMed, OVID databases, and SCOPUS for published articles from inception to November 2023, reporting on anhedonia and patient -reported outcomes in persons with MDD. The reported correlation coefficients between anhedonia and self -reported measures of both HRQoL and functional outcomes were pooled using a random effects model. Results: We identified 20 studies that investigated anhedonia with HRQoL and/or functional outcomes in MDD. Anhedonia as measured by the Snaith-Hamilton Pleasure Scale (SHAPS) scores had a statistically significant correlation with patient -reported HRQoL ( r = -0.41 [95 % CI = -0.60, -0.18]) and functional impairment ( r = 0.39 [95 % CI = 0.22, 0.54]). Limitations: These preliminary results primarily investigate correlations with consummatory anhedonia and do not distinguish differences in anticipatory anhedonia, reward valuation or reward learning; therefore, these results require replication. Conclusions: Persons with MDD experiencing symptoms of anhedonia are more likely to have worse prognosis including physical, psychological, and social functioning deficits. Anhedonia serves as an important predictor and target for future therapeutic and preventative tools in persons with MDD.