Impact of the Uncoupling Protein 1 on Cardiovascular Risk in Patients with Rheumatoid Arthritis

Adiposity is strongly associated with cardiovascular (CV) morbidity. Uncoupling protein 1 (UCP1) increases energy expenditure in adipocytes and may counteract adiposity. Our objective was to investigate a connection between expression and cardiovascular health in patients with rheumatoid arthritis (RA) in a longitudinal observational study. Transcription of was measured by qPCR in the subcutaneous adipose tissue of 125 female RA patients and analyzed with respect to clinical parameters and the estimated CV risk. Development of new CV events and diabetes mellitus was followed for five years. Transcription of was identified in 89 (71%) patients. positive patients had often active RA disease ( = 0.017), high serum levels of IL6 ( = 0.0025) and were frequently overweight ( = 0.015). IL-6BMI patients and patients treated with IL6 receptor inhibitor tocilizumab had significantly higher levels of compared to other RA patients ( < 0.0001, = 0.032, respectively). Both UCP1 groups displayed unfavorable metabolic profiles with high plasma glucose levels and high triglyceride-to-HDL ratios, which indicated insulin resistance. Prospective follow-up revealed no significant difference in the incidence of new CV and metabolic events in the UCP1 groups and remaining RA patients. The study shows that high transcription of in adipose tissue is related to IL6-driven processes and reflects primarily metabolic CV risk in female RA patients.