Does alleviating depression reduce loneliness? A longitudinal study

Background: Loneliness is a key factor affecting outcomes in depression, but its course and correlates during recovery remain understudied. Aim: To examine the prevalence, course, and psychosocial and clinical correlates of loneliness in patients with depression using a longitudinal design. Methods: In this naturalistic longitudinal study, 110 patients with current depressive episode were assessed at baseline and at 3-month follow-up using the Hamilton depression rating scale (HDRS), revised UCLA loneliness scale (RULS-6), Social Support Questionnaire, Social Connectedness Scale–Revised, Lubben Social Network Scale, Pittsburgh Sleep Quality Index, WHO quality of life scale- brief (WHOQOL-BREF), and Columbia Suicide Severity Rating Scale. Univariate analyses examined associations between loneliness and clinical and psychosocial variables, followed by multivariate regression to identify independent predictors. Results: At baseline, 94.5% of participants reported significant loneliness, decreasing to 58.2% at follow-up. Depressive symptoms improved substantially, with 31.8% achieving remission; however, 45.7% of remitted individuals continued to report loneliness. Loneliness was significantly associated with greater depression severity, poorer social connectedness, lower social support, poorer sleep quality, poorer quality of life, and higher suicidality. In multivariate regression, depression severity did not independently predict loneliness. Lower social connectedness and poorer quality of life in the social relationships domain consistently predicted loneliness across assessments. Conclusion: Loneliness remains highly prevalent in depression and often persists despite symptomatic improvement. Findings suggest loneliness represents a partially distinct therapeutic target requiring focused psychosocial assessment and intervention in depressive disorders.