Higher body fat percentage, higher waist circumference, and obesity are associated with an increased risk of developing rheumatoid arthritis (RA) in women, according to study results published in Arthritis Care & Research.
The study included participants enrolled in the Danish Diet, Cancer, and Health cohort (n=55,037). At baseline, information on lifestyle and anthropometric measures were recorded. The researchers identified participants who developed RA through linkage with the Danish National Patient Registry. They used Cox proportional hazards regression models stratified by gender to determine the relationships between body fat percentage, waist circumference, body mass index (BMI), and incident RA.
During a median follow-up of 20.1 years, 210 men and 456 women developed RA. In women, the risk of developing RA increased by 10% for each 5% increment in total body fat (hazard ratio [HR], 1.10; 95% CI, 1.02-1.18) and by 5% for each 5-cm increment in waist circumference (HR, 1.05; 95% CI, 1.01-1.10). Women with obesity had a nearly 50% increased risk of developing RA compared with women with a normal BMI (HR, 1.46; 95% CI, 1.12-1.90).
In male participants, the researchers did not find any clear associations between body fat percentage, waist circumference, or BMI and RA.
“It remains unknown whether the association of the development of RA with excess adipose tissue simply reflects the presence of inflammatory activity as a part of the metabolic syndrome or whether it contributes to the development of autoimmune inflammatory joint disease,” the researchers wrote.
Linauskas A, Overvad K, Symmons D, et al. Body fat percentage, waist circumference, and obesity as risk factors for rheumatoid arthritis — a Danish cohort study [published online July 5, 2018]. Arthritis Care Res. doi:10.1002/acr.23694