Birthweight tied to later risk of arthritis

NEW YORK People who have a birthweight over 10 pounds are twice as likely to develop rheumatoid arthritis when they are adults compared to individuals born with an average birthweight, according to a study published by researchers from Hospital for Special Surgery in the Annals of the Rheumatic Diseases. While the mechanism for this association is unclear, the study identifies a potentially modifiable risk factor and highlights a potential way to decrease the incidence of the disease.

“There may be a relationship between being born over 10 pounds and getting rheumatoid arthritis later in life,” said Lisa Mandl, who led the study and is an attending rheumatologist at Hospital for Special Surgery in New York City. “If there was some way that you could prevent someone from getting rheumatoid arthritis by making sure their birth weight wasn’t over 10 pounds, this is a risk factor that could be modifiable. You can’t change someone’s age. You can’t change someone’s gender, but potentially you could change someone’s birth weight. This is however only speculative at this point.”

The study population included only women who answered a 1992 survey that collected information about birthweight. After these exclusions, 87,077 individuals were included in the study and 619 of them developed rheumatoid arthritis. This was the second study performed on this matter. The first, published in 2003, included 400 individuals in Sweden and showed the same results.