
Neurological diseases such as multiple sclerosis (MS) and Parkinson's disease may be far more common than had previously been thought. A recent survey has found that one out of every 100 elderly Americans has Parkinson's, and nearly one out of every 1,000 Americans has MS.
That rate for MS, for example, is about 50 percent higher than the MS prevalence found in a comprehensive review from 1982. It is unknown whether the disease is becoming more common, or is instead being diagnosed more accurately.
The rate of Alzheimer's disease is also up substantially from past estimates, with 67 out of 1,000 American seniors affected by it. Current projections suggest that there will be roughly 10 million cases of Alzheimer's disease in the United States by 2050.
The survey projects that the number of people with Parkinson's worldwide will double over the next 25 years, rising from 4.3 million people to 9 million people.