Unfavorable Blood Fat Levels Predict Rheumatoid Arthritis Up to 10 Years in Advance

An unfavorable ratio of blood fats could herald the development of the inflammatory joint disease rheumatoid arthritis up to 10 years later, suggests research published ahead of print in the Annals of Rheumatic Diseases. The authors base their findings on analysis of more than 2000 blood samples donated to a blood bank in The Netherlands.

They analyzed the fat content of 1078 deep frozen blood samples from 79 people who had given blood between 1984 and 1999 and subsequently went on to develop rheumatoid arthritis 10 or more years later. In particular, they looked at levels of total cholesterol, high density lipoprotein, triglycerides, apolipoproteins A and B, and lipoprotein (a). The samples were then compared with those taken from 1071 randomly selected blood donors, matched for age, sex, and storage time.

They found that the samples of people who subsequently developed rheumatoid arthritis had a more unfavorable balance of circulating blood fats than the samples of those who did not develop the disease. On average, total cholesterol was 4% higher, while high density lipoprotein levels were 9% lower. Triglycerides were 17% higher and apolipoprotein B was 6% higher.

Taken together, these figures also indicate an increased risk of ischemic heart disease, in which the artery walls are thickened and hardened by fat deposits. This might help to explain the link between an increased risk of cardiovascular disease among patients with rheumatoid arthritis, say the authors. The authors speculate that a poorer blood fat ratio might make a person more susceptible to inflammation or inflammatory diseases, such as rheumatoid arthritis.