Background Increased concentrations of leptin have been observed during infectious processes and inflammation, in such a way that it plays a role in the inflammatory and the immune response
Objectives Determine the association between serum leptin and disease activity measured through DAS-28 PCR.
Methods Patients with the diagnosis of rheumatoid arthritis (RA) according to the ACR/EULAR 2010 criteria were studied. Leptin was determined by enzyme immunoassay (ELISA) with the TECO® Test Kit, the values higher than 17ng/mL were considered as hyperleptinemia. Disease activity was assessed by the DAS-28 PCR, classifying as remission <2.3, low activity ≥2.3 to <3.8, moderate activity as ≥3.8 to <4.9 and high activity ≥4.9. Statistical analysis was performed using the SPSS 22.0 package. A p≤0.05 was considered a significant result. A multivariate logistic regression model was used to determine the association between significant variables and leptin concentrations.
Results 77 patients were studied, 93,5% were female. The activity of the disease was determined, finding that 40,3% of patients were in remission, 41,6% had low activity, 11,7% had moderate activity and 6,5% had high activity. The 46,8% had obesity, 32,5% were overweight, 18,2% had normal weight and 2,5% were underweight. The 37,7% of the patients studied had metabolic syndrome, being the main factor the presence of an altered abdominal perimeter. The 63,6% had positive rheumatoid factor. The 71,4% had leptin levels ≥17 ng/ml. A multivariate logistic regression was performed with leptin as dependent variable. The results show an independent association between higher concentrations of leptin and disease activity (OR 1,9; 95% CI 1,3–3,8; p=0,045), obesity (OR 3,63; 95% CI 1,1–11,9; p=0,033), the presence of metabolic syndrome (OR 2,74; 95% CI 1,7–10,4; p=0,038), and positive rheumatoid factor (OR 3,5; 95% IC 1,2–11,3; p=0,033). It was also found that at higher disease activity, there were higher concentrations of serum leptin. Patients with severe activity had higher leptin media than patients in remission
Conclusions There is a positive relationship between the activity of the disease and the serum leptin concentration, likewise this hormone is related to other inflammatory processes such as metabolic syndrome and rheumatoid factor.
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Disclosure of Interest None declared