Adding short-term psychodynamic psychotherapy (STPP) to antidepressants increases treatment efficacy, but it is unclear which patients benefit specifically. This study examined efficacy moderators of combined treatment (STPP + antidepressants) v. antidepressants for adults with depression.

For this systematic review and meta-analysis (PROSPERO registration number: CRD42017056029), we searched PubMed, PsycINFO, Embase.com, and the Cochrane Library from inception to 1 January 2022. We included randomized clinical trials comparing combined treatment (antidepressants + individual outpatient STPP) v. antidepressants in the acute-phase treatment of depression in adults. Individual participant data were requested and analyzed combinedly using mixed-effects models (adding Cochrane risk of bias items as covariates) and an exploratory machine learning technique. The primary outcome was post-treatment depression symptom level.

Data were obtained for all seven trials identified (100%, n = 482, combined: n = 238, antidepressants: n = 244). Adding STPP to antidepressants was more efficacious for patients with high rather than low baseline depression levels [B = −0.49, 95% confidence interval (CI) −0.61 to −0.37, p < 0.0001] and for patients with a depressive episode duration of >2 years rather than <1 year (B = −0.68, 95% CI −1.31 to −0.05, p = 0.03) and than 1–2 years (B = −0.86, 95% CI −1.66 to −0.06, p = 0.04). Heterogeneity was low. Effects were replicated in analyses controlling for risk of bias.

To our knowledge, this is the first study that examines moderators across trials assessing the addition of STPP to antidepressants. These findings need validation but suggest that depression severity and episode duration are factors to consider when adding STPP to antidepressants and might contribute to personalizing treatment selection for depression.

The duration of untreated illness (DUI) is a potentially modifiable parameter associated with worst prognosis in several psychiatric disorders, but poorly investigated in Obsessive-Compulsive Disorder (OCD). Our aims were to estimate the mean DUI in a large sample of individuals with OCD and its impact on response to the first ever adequate SRI treatment.

We retrospectively examined records of 251 patients with OCD (SCID-I, DSM-IV) who referred to our Department and were prospectively and naturalistically treated according to International Guidelines. The DUI was defined as the interval between age at onset and age at which patients received their first adequate pharmacological treatment. Response rates were compared in subjects with brief (≤24 months) versus long DUI. Logistic regression models predicting response and 12-week Y-BOCS score were run with DUI (among others) as independent variable.

The mean DUI was 106.19 ± 118.14 months, with a mean interval between onset of the disorder and when patients sought professional help of 82.27 ± 112.30 months. Response rates were significantly reduced in subjects with a long DUI, using both the cut-off of 24 months and the median value of 60 months. Regression analyses confirmed that a long (>24 months) DUI predicts poorer response and higher Y-BOCS scores at 12 weeks.

Our results, although preliminary, seem to suggest that a longer duration of untreated illness in OCD is associated with poorer outcome in terms of response to SRI treatments. It is imperative to do all the possible to shorten the DUI, both by improving access to mental health services, improving the ability of primary care physicians and mental health professionals to recognize OCD, and disseminate best-practice prescription guidelines.