A higher body mass index (BMI — an estimate of body fat based on weight and height) was associated with greater CRP in women with rheumatoid arthritis and women in the general population, especially in severely obese women. There was also a modest association between obesity and ESR.
Conversely, in men with rheumatoid arthritis, a lower BMI was associated with greater CRP and ESR.
The findings may help improve understanding of the link between weight and inflammation. It may also help doctors learn more about how this relationship differs between women and men, the study authors added.
The findings were published April 10 in the journal Arthritis Care & Research.
“Our results suggest that obesity may lead to increased levels of CRP and ESR in women with rheumatoid arthritis,” George said in a journal news release.
“The increase in these levels of inflammation was not because rheumatoid arthritis was worse in these women,” he said.
“In fact, we found that obesity leads to very similar increases in these lab tests even in women without rheumatoid arthritis,” he added.
Doctors should be careful when interpreting the results of these lab tests since both rheumatoid arthritis and obesity can contribute to inflammation levels, George said.