The Mind-skin Interface: Depression Prevalence, Comorbidities and Treatment Outcomes in Patients with Psoriasis

Background: Psoriasis is a chronic inflammatory dermatosis associated with substantial psychological morbidity. Indian data on depression in psoriasis remain limited, and the impact of depressive symptoms on treatment outcomes is inadequately studied. Objectives: To estimate the prevalence of depression amongst patients with psoriasis attending a tertiary-care dermatology outpatient department, to validate depression screening using a structured psychiatric interview and to evaluate associations with clinical characteristics, comorbidities and treatment outcomes. Methods: This hospital-based cross-sectional study with a 12-week follow-up included 70 adult patients with clinically diagnosed psoriasis. Depression was screened using the Patient Health Questionnaire-9 (PHQ-9) and validated in a randomly selected subset using the Mini International Neuropsychiatric Interview (MINI). Disease severity was assessed using the Psoriasis Area and Severity Index (PASI). Medical comorbidities were systematically recorded and treatment response was evaluated at follow-up. Results: Depression was identified in 29 patients, yielding a prevalence of 41.4% (95% confidence interval: 29.8%–53.8%). Psychiatric validation demonstrated 89% concordance between PHQ-9 and MINI diagnoses (κ =0.78, P < 0.001). Depression severity showed no significant correlation with baseline PASI scores. Patients with depression had significantly poorer treatment response at 12 weeks, with lower mean PASI improvement and reduced PASI-75 response rates compared to non-depressed patients ( P < 0.05). Conclusions: Depression affects over two-fifths of Indian patients with psoriasis and is associated with suboptimal treatment outcomes independent of disease severity. Routine depression screening and integrated dermatology–psychiatry care are the essential components of comprehensive psoriasis management.