Background/Purpose: Obesity has been proposed as a risk factor to develop rheumatoid arthritis (RA) and it has been associated with a worse response to several disease modifying anti-rheumatic drugs (DMARDs). Objective: To study the differences in baseline characteristics according to the body mass index (BMI) of patients in the PEARL (Princesa Early Arthritis Register Longitudinal) cohort.

Methods: A total of 432 patients (69.1% female) of the PEARL cohort were included for this study. The register protocol comprises the collection of sociodemographic, disease-related and treatment data in five visits (baseline, 6, 12, 24 and 60 months). The local ethics and clinical research committee approved the register protocol and all patients sign an informed consent prior to their inclusion. For this study it was analyzed the data of the baseline visit from the 304 (70.37%) patients that met ACR 1987 criteria for RA after 2 years of follow-up, as well as those considered undifferentiated arthritis (UA)since other diagnoses were excluded. The WHO definition for low weight, normal weight, overweight and obesity (BMI <18.5, 18.5-25, 25-30 or ≥30 kg/m2 respectively) was applied. ACPA were assessed by enzyme immunoassay (CCP2 Eurodiagnostica). HLA-DRB1 genotype was determined in 219 patients using specific HLADRB1 typing kits (Dynal RELI SSO). A multivariate logistic regression was performed to determine which factors may be related to ACPA positivity, including BMI, age, sex, smoking habit, number of SE alleles and study level as independent variables.

Results: Patients were 54.9 years old [44.2-67.5] (median [p25-p75]); disease duration was 5.3 months [3-8.4]. Differences in pain perception and dysability were related to BMI. Table 1 shows the main variables significantly associated to BMI. It was observed an inverse relationship between the presence of ACPA and BMI as well as a lower frequency of SE in patients with a higher BMI. The multivariate analysis, performed with the data of the 219 patients in whom the genetic study was available, showed, as previously described, that being smoker (everorcurrent) and carrying SE alleles is associated with the presence of ACPA. Moreover, adjusted by these variables, overweight and obesity were associated with a significantly lower probability of suffering an ACPA positive disease(OR 0.49, p = 0.027 and OR 0.39, p = 0.019 respectively).

Table 1 – Variables significantlydifferentaccordingto BMI

*W: women; M: men; N: no studies; P: primary studies; Se: secondary studies; U: universitary studies.

Conclusion: In our early arthritis registry, patients with a higher BMI have predominantly ACPA negative disease, a more intense perception of pain and higher disability. These findings should be validated in other populations.

« Back to 2017 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/does-the-body-mass-index-have-any-influence-in-the-characteristics-of-early-arthritis-patients/