Smoking and obesity in systemic lupus erythematosus: a cross‐sectional study

Background Both smoking and obesity have been demonstrated as risk factors in several autoimmune diseases. Little is known about the relationship between systemic lupus erythematosus ( SLE ) and both smoking and obesity. Objectives To investigate the association between SLE , tobacco consumption and body mass index ( BMI ). Materials and methods Using data from the largest Health Maintenance Organization ( HMO ) in Israel, the Clalit Health Services, we searched for an association between SLE , smoking and obesity. Chi‐square and t ‐test were used for univariate analysis, and a logistic regression model was used for multivariate analysis. Data available from Clalit Health Services database included age, sex, BMI , smoking status, socioeconomic status ( SES ) and diagnoses of chronic diseases. Results The study included 5018 patients with SLE and 25 090 age‐ and sex‐matched controls. In multivariate analysis, we found a significant association between smoking and SLE ( OR = 1·91). Conversely, there was no association between BMI and SLE . Conclusion In this study, we have shown that smoking is independently associated with SLE , whereas BMI scores were not.