April 1, 2009

Does MS Protect Against Cancer?

People with multiple sclerosis (MS) have a lot of health issues to worry about. But cancer may be lower on the list for them than for most people.

Researchers who compared the health records of 20,000 people with MS with 204,000 people without the condition found about a 10 percent reduction in the risk of developing cancer in the people with MS. While the across the board risk was lower, however, people with MS did have an increased risk of certain types of the disease, including brain cancer and urinary tract cancers.

Why would MS patients have a lower risk of cancer? The researchers believe it could have something to do with lifestyle factors related to MS. For example, people with MS tend to have lower body mass index (BMI) than people without MS. Higher BMIs are linked to many forms of cancer.

The investigators also have an explanation for the higher risk for brain cancer seen in the study, noting people with MS receive more frequent neurological exams, and these exams could simply be catching more cancers sooner. MS can also lead to chronic irritation of the urinary track, which might explain the higher risk seen there as well.

SOURCE: Neurology, published online March 30, 2009