Tobacco smoking is viewed as a behavioral risk factor for psoriasis initiation and progress, even among those undergoing biologic treatment. However, evidence regarding the association between tobacco smoking and treatment response to biologics among patients with psoriasis is limited. This study aimed to explore the impact of tobacco smoking on the efficacy of biologic treatment in patients with psoriasis. Patients with psoriasis undergoing biologic treatment were recruited from 2022 to 2024 at the Shanghai Skin Disease Hospital. Demographic characteristics and smoking habits were collected using a structured questionnaire. Clinical features and treatment efficacy were assessed and recorded by dermatologists at baseline and weeks 4, 8, 12, 24, and 48 after treatment, and the Psoriasis Area and Severity Index (PASI) 75 and PASI 90 measures were calculated for treatment efficacy evaluation. A total of 192 patients with psoriasis were included, of whom 78 (40.6%) were tobacco smokers, with a higher smoking prevalence observed in male patients (74/154, 48.1%). The PASI 75 response rates at weeks 4, 8, 12, 24, and 48 were 29.2% (56/192), 54.2% (104/192), 78.6% (151/192), 84.5% (153/181), and 82.7% (134/162), respectively. The PASI 90 response rates increased from 13.0% (25/192) at week 4 to 62.4% (113/181) at week 24 and 59.9% (97/162) at week 48. Logistic regression analysis indicated that nonsmoking patients with psoriasis had a high PASI 75 response rate. The adjusted odds ratios were 2.57 (95% CI 1.19-5.53), 2.61 (95% CI 1.34-5.08), 2.62 (95% CI 1.13-6.04), 2.27 (95% CI 0.89-5.75), and 2.75 (95% CI 1.01-7.49) at weeks 4, 8, 12, 24, and 48, respectively. Moreover, nonsmoking patients with psoriasis also had a higher PASI 90 response rate than those who smoked. The odds ratios ranged from 1.32 (95% CI 0.49-3.54) to 2.59 (95% CI 1.21-5.55). Correlation analysis showed that both tobacco smoking duration and daily cigarette consumption were negatively correlated with the reduction in PASI score at weeks 4 to 48 after treatment (P<.05). Tobacco smoking was negatively associated with treatment response among patients with psoriasis undergoing biologic treatment, especially among patients with longer tobacco smoking duration and higher daily cigarette consumption.
