Multiple sclerosis is a lifelong autoimmune disease in which a person’s immune system attacks the nerve fibers in their spinal cord and brain. A recent study published in the August 31 issue of Neurology has confirmed a long held theory that there is a seasonal pattern to the disease.
Multiple Sclerosis Symptoms Have Seasonal Patterns: The Study
The study, conducted at Brigham and Women’s Hospital in Boston and Washington University in St. Louis, looked at MRIs of multiple sclerosis patients from 1991 to 1993 and compared them with weather data from the same time. MRIs are the main tool used to monitor the progress of multiple sclerosis as it allows doctors to see scarring of the brain, called lesions, caused by the disease. The study was specifically testing the theory that multiple sclerosis symptoms have seasonal patterns.
Study Finds Multiple Sclerosis Symptoms Have Seasonal Patterns
The results were astounding. Scientists found an increase in the numbers of T2 brain lesions in multiple sclerosis patients between March and August. The overall intensity of the disease also increased during that time. Researchers believe that the reason for this may be because warmer temperatures and increased solar radiation present during the warm spring and summer months somehow fuels multiple sclerosis.
Brain Lesions Peak in Spring and Summer
Brain scans showed T2 brain lesions in patients involved in the study were two to three times higher between March and August when compared to other months of the year. Researchers have linked more brain lesions in multiple sclerosis patients to the warmer temperatures and increased amounts of solar radiation present in the environment in summer. Though it is clear that the link exists, lead researcher Dominik Meier, PhD, of Brigham and Women’s Hospital in Boston, Mass. revealed that more study is needed to better understand the complete nature of the connection.
An Important Study
This is an important scientific study for multiple sclerosis patients and doctors. The study analyzed data from the early 1990’s, before approved medications for multiple sclerosis relapse were approved and came into widespread use. That means medications did not affect the outcomes of the study. Because medications are now used to treat recurring multiple sclerosis relapses, it is unlikely that the conditions will ever again exist to allow this study to be repeated.
Other Research Has Found That Multiple Sclerosis Symptoms Have Seasonal Patterns
U.S. research results are in agreement with results in other countries. Studies in Japan and Sweden have also found that multiple sclerosis symptoms have seasonal patterns. Taken together, this entire body of research sets the stage for developing new treatments and drugs that target disease symptoms using seasonal criteria.
Role of Environment
There is more research needed to look at how and why the environment increases multiple sclerosis disease activity. The link has been made, now researchers need to look at why it exists. It had long been suspected that multiple sclerosis symptoms have seasonal patterns. Now there is proof. Scientists hope that this study is a breakthrough for better understanding multiple sclerosis and can act as a springboard for developing new treatments and medications.
What Does This Mean for Multiple Sclerosis Patients?
According to the National Multiple Sclerosis Society, approximately 400,000 people in the U.S. and 2.1 million people worldwide suffer from the disease. What do the results of the study mean for them? The results may impact testing and development of new multiple sclerosis drugs. Most drug trials last anywhere from 6 to 12 months. Drug developers will now have to account for seasonal differences in the disease.
Continued research and analysis of the study may eventually yield important clues to the workings of multiple sclerosis and how it progresses.