Poster Topical Area: Energy and Macronutrient Metabolism
Location: Hall D
Poster Board Number: 476
Objectives: Being overweight or obese increases the risk of rheumatoid arthritis (RA) among women. We investigated whether abdominal obesity predicts RA risk in two large prospective cohorts, the Nurses' Health Study (NHS) and Nurses' Health Study II (NHSII).
Methods: We followed 48,919 women in NHS (aged 40-67 years in 1986) and 47,220 women in NHSII (aged 29-48 years in 1993) without RA at baseline. Lifestyle and environmental exposures and anthropometric measures were collected through biennial questionnaires. Incident RA cases were identified using the previously validated connective tissue disease screening questionnaire followed by a medical record review. RA serologic status was determined by positive rheumatoid factor (RF) or anti-citrullinated peptide antibodies (ACPA) in the medical record. Abdominal obesity was measured using waist circumference (WC) reported in 1986, 1996 and 2000 in NHS and 1993 and 2005 in NHS II. The cutoff point for abdominal obesity (WC≥88cm) was based on WHO recommendations. Using pooled data from the two cohorts, we estimated hazard ratios (HR) for RA risk using time-varying Cox proportional hazards models. We repeated analyses restricted to young and middle aged women (age≤55 years).
Results:During 28 years of follow-up, we identified 807 incident RA cases (510 in NHS, 297 in NHSII). Age-adjusted incidence rates were 33 /100,000 person-years in NHS, and 28 /100,000 person-years in NHSII. Women with WC>88cm had increased RA risk compared with women with WC
Conclusions: In this prospective cohort study of women followed up to 28 years, abdominal obesity was significantly associated with increased risk of developing RA. Abdominal obesity conferred the greatest risk for seropositive RA among women ≤55 years old independent of BMI.
Brigham and Women's Hospital / Harvard Medical School