Seasons Affect MS Symptoms

At the age of 45, Anne Rowling died from complications of multiple sclerosis (MS). Her daughter, J.K. Rowling, of Harry Potter fame, recently announced she was donating £10 million ($15.4 million) to form a MS and neurodegenerative disease research center at the University of Edinburgh. Scottish people suffer from the disease at a higher rate than others and the disease seems to impact more people living in northern regions. Researchers at Brigham and Women's Hospital discovered that the seasons impact MS symptoms, causing them to seriously consider the role environment plays in causing the disease.

MS is an autoimmune disease where the body destroys myelin sheaths, a fatty material that protects the nerve endings in the brain and the spine. This lessens the brain's ability to communicate and often causes scarring and lesions, leading to permanent disability. (The image at left, from Wikimedia user Marvin 101, is a photomicrograph of a demyelinating MS-Lesion.) There are no known cures for the disease but many physicians have been able to slow the disease's progression.

Researchers led by Dominik Meier examined MRI scans of 44 participants. The scientists asked participants, between ages 25 and 52, to undergo eight weekly scans, then eight scans every other week, followed by a six-month check-up. Each person averaged 22 scans. When each scan was taken, researchers recorded weather information such as temperature, precipitation, and solar radiation levels. The study took place from 1991 through 1993 before pharmaceuticals that regulate MS relapses entered the market.

Meier and his colleagues found that more brain lesions occurred from March to August. According to the paper, published in Neurology, 310 new T2 lesions were found in 31 patients and the researchers discovered more lesions during periods of higher levels of solar radiation.