Yes, you can be too thin - if you have rheumatoid arthritis. Weighing less than normal appears to increase the risk of dying from heart disease for people with arthritis, results of a population-based study indicate.

“This may appear to be counter-intuitive at first glance,” Dr. Sherine E. Gabriel told Reuters Health, noting that “in most people, a high BMI (a measure of weight in relation to height) is a risk factor for heart disease.”

Gabriel and a team at the Mayo Clinic in Rochester, Minnesota, compared BMI patterns and cardiovascular deaths in 603 patients with rheumatoid arthritis and a like number of matched but arthritis-free “controls” who were followed for an average of 27 years prior to and 15 years after a diagnosis of rheumatoid arthritis.

By the end of that period, 356 participants with arthritis (59 percent) and 306 without (51 percent) had died. The underlying or contributing cause of death was cardiovascular disease in 214 arthritis patients and 167 non-arthritis subjects, according to a report in the medical journal Arthritis and Rheumatism.

The investigators found that arthritis patients with a low BMI at the time of diagnosis were more than three times more likely to die of heart disease compared with non-arthritis, normal-weight individuals.

Arthritis patients with a normal BMI at diagnosis who lost weight during follow-up were twice as likely to die of cardiovascular causes as control subjects who maintained a normal BMI over the years.

“This is important for doctors caring for people with rheumatoid arthritis because it means that they need to pay close attention to cardiovascular disease prevention and care among their rheumatoid arthritis patients, especially their thin rheumatoid arthritis patients,” Gabriel said.

“It is likely that patients with the most severe forms of rheumatoid arthritis typically have very active systemic inflammation, which can be associated with weight loss,” Gabriel told Reuters Health.

If a low body weight in people with rheumatoid arthritis is a consequence of inflammation, then the current findings support the idea that inflammation may play a role in cardiovascular disease, she and her colleagues point out.

SOURCE: Arthritis and Rheumatism, November 2004.