Multiple Sclerosis severity might change with seasons

Patients show higher levels of disease activity in spring and summer

By comparing brain scans of patients with weather patterns, U.S. researchers have found that patients show higher levels of disease activity in the spring and summer, the BBC reports, which could have implications for testing new medicines that might show different results in different times of year. While it isn’t clear why warm weather might be a factor, other studies have suggested that vitamin D from the sun could have a protective effect against MS, which is a long-term inflammation of the central nervous system. By comparing MRI brain scans of 44 people (from 1991 to 1993) with temperature, solar radiation and precipitation over the same time, they found that lesions were up to three times more likely to appear in warmer spring and summer months. Adults with untreated MS had eight weekly scans, then eight scans each two weeks, then six monthly checkups, averaging 22 scans per person; after one year, 310 new brain lesions were found in 31 people.


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