Anhedonia is one of the two symptoms, along with depressed mood, indispensable for the DSM-5 diagnosis of major depressive disorder. However, anhedonia in depressed patients is poorly explored in terms of prevalence or correlation with other clinical features.

The HEDONIE study aimed to explore the patterns and course of anhedonia in major depressive disorder.

1657 patients were followed over 10 to 12 weeks and assessed with the QIDS-SR, MADRS, CGI, SHAPS and SDS.

At inclusion, the mean QIDS-SR score was 17.4 ± 4.2 and the mean MADRS score was 32.6 ± 7. The mean SHAPS score was 9.8 ± 3.6 and 86.2% of the patients had a SHAPS > 5, which can be considered as a severe anhedonia. Patients with severe anhedonia had a significantly higher QIDS-SR mean score. The SDS total score was 22.1 ± 4.7. Patients were mainly treated with agomelatine (91, 3%).

At last visit, significant reductions were observed in QIDS-score (−11.0 ± 5.7, P<0.0001), MADRS score (−21. 2 ± 9.3, P<0.0001), SHAPS score (−6.9 ± 4.6, P<0.0001) and SDS score (−12.7 ± 7.8, P<0.0001). The correlation between improvement of anhedonia and improvement of functioning was strong (r=0.646; P<0.0001).

This study emphasizes the high prevalence of anhedonia in depression and the importance of its screening and evaluation, given its consequences in terms of functionality. The improvement in anhedonia and functioning observed in this study may be due to the specific antidepressant efficacy profile of agomelatine, already demonstrated in other trials.