BMI matters: understanding the link between weight and severe psoriasis

Area of Science:

• Medical Genetics
• Dermatology
• Epidemiology

Background:

• Psoriasis (PsO) is a chronic inflammatory disease.
• Obesity, indicated by Body Mass Index (BMI), is a common comorbidity.
• The causal relationship between BMI and PsO severity requires further investigation.

Purpose of the Study:

• To investigate the causal relationship between Body Mass Index (BMI) and Psoriasis (PsO) severity.
• To assess the impact of BMI on PsO development and clinical outcomes.

Main Methods:

• Bidirectional Mendelian Randomization (MR) analyses using large-scale Genome-Wide Association Study (GWAS) data for BMI.
• Regression analyses on a cohort of 1,979 psoriasis patients assessing Psoriasis Area and Severity Index (PASI), Body Surface Area (BSA), and Dermatology Life Quality Index (DLQI).

Main Results:

• MR analyses indicated a significant causal association between increased BMI and higher risk of developing psoriasis (MR1 OR 2.28, MR2 OR 2.37).
• Logistic regression showed a 6% increased risk of severe psoriasis for every 1-unit increase in BMI.
• Linear regression demonstrated that higher BMI correlated with increased PASI, BSA, and DLQI scores.

Conclusions:

• Abnormal weight gain, reflected by BMI, is causally linked to increased psoriasis risk and severity.
• Clinicians should emphasize weight management and nutritional balance in managing psoriatic disease.