NEW YORK (Reuters Health) – People who were heavier than average when they were born appear to be twice as likely to develop rheumatoid arthritis as their normal birth-weight counterparts, researchers report.

Findings from several small studies have hinted at links between high birth-weight and rheumatoid arthritis as well as other autoimmune diseases, Dr. Lisa Mandl, at the Hospital for Special Surgery in New York City, and her colleagues note in the Annals of the Rheumatic Diseases.

To investigate further, Mandl’s group analyzed data from the Nurses’ Health Study, which included 87,000 women 30 to 55 years old at the start of the study in 1976. A total of 619 subjects were subsequently diagnosed with rheumatoid arthritis.

The likelihood of being diagnosed with rheumatoid arthritis was doubled in women born weighing more than 10 pounds, compared with those born weighing 7 to 8.5 pounds, considered the average birth weight.

“If fetal nutrition has an impact on future risk of rheumatoid arthritis, this could be a potentially modifiable risk factor,” Mandl and her colleagues suggest.

Their findings, they add, “provide further evidence for the importance of fetal environment as a crucible for future adult diseases.”

SOURCE: Annals of the Rheumatic Diseases, online June 30, 2008.