The role of obesity (and weight loss through bariatric surgery) in autoimmune diseases

Introduction: Obesity has been linked to the onset or worsening of autoimmune diseases. Objective: To review the presence of autoantibodies in obese patients undergoing bariatric surgery and verify the possible change in this profile after the surgical procedure. Method: Narrative review of the literature carried out in PubMed and Scielo. The search used the keywords: “obesity, autoimmunity, antinuclear factor, bariatric surgery”. The inclusion criteria comprised review articles, experimental studies, pre-clinical and clinical research, written in Portuguese and English and available in full text. Result: 63 articles were included. Conclusion: There is a high prevalence of positive ANA in the obese population and candidates for bariatric surgery, which decreases considerably post-operatively. The same cannot be verified with rheumatoid factor, ENA and anti-ds DNA antibodies, IgG and IgM anticardiolipin antibodies, and anti-endomysium antibodies. No clinical or anthropometric variables could be linked to the presence of autoantibodies, except for vitamin D levels, which were significantly lower in preoperative and ANA-positive individuals.