P33 The impact of body mass index on psoriasis area and severity index response in patients treated with adalimumab

Abstract Obesity and psoriasis are bidirectionally linked. Some biologics are given in higher doses in patients >90 kg while others have only one licensed dose. The bioavailability of subcutaneous medication is negatively impacted by fat volume with body mass index (BMI) a potential negative effector on treatment response. Our aim was to assess the impact of baseline BMI on psoriasis area and severity index (PASI) 75 response with adalimumab treatment. Patients recruited to BADBIR with complete datasets in our centre were included. Information was collected from BADBIR records and local electronic care records including age, gender, baseline BMI and PASI at baseline, 6 and 12 months. Statistical analysis was completed using Jamovi v2.0 (Sydney, Australia). We identified 46 patients including 33 males (71.7%) with a median age of 45.5 years [interquartile range (IQR) 35–51]. Most patients were overweight/obese (n = 38, 82.6%) with a median BMI of 29.1 kg/m2 (IQR 25.7–34.6). Disease severity was moderate-to-severe (n = 44, 95.7%) with a median PASI of 12.1 (IQR, 10.3–17.6). Using linear regression analysis, for every 1 standard deviation (SD) increase in baseline PASI, baseline BMI increased by 1.1 kg/m2. Conversely, for every 1 SD increase in baseline BMI, baseline PASI increased by 1.2. Using binomial regression, baseline BMI did not predict PASI75 response at Month 6 (P = 0.786) or Month 12 (P = 0.117). Data regarding the impact of BMI on treatment response in psoriasis are important to predict PASI response on an individualized patient basis. Studies have been conflicting with some suggesting higher weight in treatment-refractory patients and others identifying no difference. We have identified a reciprocal effect between PASI and BMI but fall short of identifying BMI as a predictor of PASI75 response. Large-scale studies including multiple biologic agents are required to further evaluate this.