Residual symptoms and functioning in depression, does the type of residual symptom matter? A post-hoc analysis

Patients with MDD who responded (≥50% on the 17-item Hamilton Rating Scale for Depression; HAMD-17) after 3？months of treatment (624/930) were included. Residual core mood-symptoms (HAMD-17 core symptom subscale ≥1), residual insomnia-symptoms (HAMD-17 sleep subscale ≥1), residual anxiety-symptoms (HAMD-17-anxiety subscale ≥1), residual somatic-symptoms (HAMD-17 Item 13 ≥1), pain (Visual Analogue Scale ≥30), and functioning were assessed after 3？months treatment. A stepwise logistic regression model with normal functioning (Social and Occupational Functioning Assessment Scale ≥80) as the dependent variable was used.After 3？months, 59.5% of patients (371/624) achieved normal functioning and 66.0% (412/624) were in remission. Residual symptom prevalence was: core mood symptoms 72%; insomnia 63%; anxiety 78%; and somatic symptoms 41%. Pain reported in 18%. Factors associated with normal functioning were absence of core mood symptoms (odds ratio [OR] 8.7; 95% confidence interval [CI], 4.6–16.7), absence of insomnia symptoms (OR 1.8; 95% CI, 1.2–2.7), episode length (4–24？weeks vs. ≥24？weeks [OR 2.0; 95% CI, 1.1–3.6]) and better baseline functioning (OR 1.0; 95% CI, 1.0–1.1). A significant interaction between residual anxiety symptoms and pain was found (p？=？0.0080).Different residual symptoms are associated to different degrees with patient functioning. To achieve normal functioning, specific residual symptoms domains might be targeted for treatment.Residual symptoms of depression cause significant functional impairment [1,2]. This has been reported in patients who respond but are not remitters, partial remitters [1,2], and even in remitters (typically defined as a score of ≤7 on the 17-item Hamilton Depression Rating scale [HAMD-17]) with residual symptoms [2]. Residual symptoms are also associated with persistent functional impairment [1]. However, little is known about the role of specific residual symptom domains, such as core symptoms, symptoms of anxiety, somatic