Background The rheumatoid factor (RF) and anti-citrullinated protein antibodies (ACPA) autoantibodies in rheumatoid arthritis (RA), have been used as diagnostic and prognostic tools . However, this traditional perspective has changed toward a major role in RA pathogenesis. Several studies have demonstrated that FR and ACPA autoantibodies positivity beyond its level, might influence disease activity, bone erosions and development of comorbidities. Anti-Ro52kDa antibodies have also been associated with disease severity in RA and might influence the development of comorbidities such as insulin resistance (IR) in RA.
Objectives To evaluate the association between RF, ACPA and anti-Ro52 kDa and IR in RA patients.
Methods We included 83 RA patients classified according to ACR 1987 and ACR/EULAR 2010 criteria and 90 controls matched for age, gender and body mass index (BMI). Homeostasis Model Assessment-Insulin Resistance (HOMA-IR), anthropometric parameters and antibody positivity (RF, ACPA, Ro52 kDa) were evaluated. Multivariate regressiόn analysis was used to assess the contribution of autoantibodies, adiposity and disease activity to insulin resistance in RA.
Results Patients positive for RF or anti-Ro52 kDa showed higher levels of basal insulin (P=0.009, P=0.006) and HOMA-IR. DAS-28 ESR was correlated with basal insulin (r=0.31, P=0.01) and HOMA-IR (r=0.29, P=0.02). We also observed positive correlations between serum triglycerides (r=0.47, P=0.01) and HDL-c (r=-0.38, P=0.02) and basal insulin. Multivariate analysis showed that Triglycerides, HDL-c, DAS-28, RF and anti-Ro52 kDa were independent predictors of basal insulin and HOMA-IR in patients with RA.
Conclusions In RA, RF or anti-Ro52 kDa are independent predictors of IR. This phenomenon might be linked to the network of inflammation, adipokine secretion, since disease activity was also precitive of higher basal insulin. Both RF and anti Ro52 kDa, along with disease activity are independent predictors of IR in RA patients without comorbidities.
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Disclosure of Interest None declared