Is the occurrence of multiple sclerosis increasing since I am meeting more persons with MS than previously?
We do not know the actual prevalence (number of persons with a disease at any given time) with multiple sclerosis. The estimated number varies from 250,000 to 450,000 in the United States. It is my impression that your observation is correct that the number of diagnosed individuals has increased but it does not necessarily mean that the disease itself has increased. The reason for the apparent increase in the number of diagnosed individuals is not clear. There are several possible explanations:
- An actual increase in the occurrence of the disease for reasons not yet identified.
- More readily available diagnostic modalities, particularly MRI scans, that facilitate the diagnosis.
- Heightened awareness and improvement in the reporting of the disease.
- A push toward diagnosis since there are now available good drug treatments.
I suspect that it is some of all of the above. Specifically in North Carolina a shift in population, that is, migration from other parts of the United States, particularly from the north, may account for an increase that may not necessarily reflect an overall change in the prevalence of the disease in the United States. We hope that epidemiological analysis will give us clues as to the cause or at least a better understanding of the disease. Such is the case with vitamin D. It has been known for a long time that multiple sclerosis is less common as one goes south towards the equator. Vitamin D may play a role by virtue of the relationship between it and sunlight exposure. Thus many have advocated taking vitamin D as part of the treatment. It is reassuring that data such as this is being continuously analyzed.
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