May's Article of the Month: Psychological interventions reduce subclinical depressive symptoms and protect against worsening for up to a year after treatment
The Research and Communication Committee of the Department of Clinical and Health Psychology has selected the article “Psychological intervention in individuals with subthreshold depression: individual participant data meta-analysis of treatment effects and moderators” as May's article of the month
This work has been published in the British Journal of Psychiatry which has an impact factor of 8.8 (top decile in the Psychiatry category of the JCR), and involved over 70 international researchers. Among the authors is Dr. Juan Vicente Luciano, member of the Department of Clinical and Health Psychology at the UAB, who actively contributed to this large-scale collaborative research.
The meta-analysis, which includes data from over 10,000 participants, shows that psychological interventions for individuals with subthreshold depression (depressive symptoms without a diagnosis of major depression) are effective in reducing symptoms and preventing their intensification for at least one year. The benefits observed at two years are less clear and only persist among individuals with more severe symptoms at baseline.
The authors examined both symptom reduction and reliable improvement, as well as the risk of deterioration, and found that interventions such as cognitive-behavioral therapy or behavioral activation have clearly beneficial effects, especially for individuals scoring 10 or more on the PHQ-9, indicating moderate depressive symptoms. In contrast, among individuals with very mild symptoms (PHQ-9 = 5), benefits were smaller but still meaningful, opening the door to offering scalable treatments (such as digital interventions) in these cases.
The study also shows that these interventions have a protective effect against symptom worsening—a key finding supporting their preventive use. However, effects begin to fade after 12 months, and by 24 months, no significant differences are observed between treatment and control groups. The authors suggest future studies to explore maintenance strategies, such as booster sessions one year post-treatment.
This international collaborative effort provides strong support for the use of psychological interventions as a preventive strategy for major depression and highlights the importance of tailoring treatment based on initial symptom severity.