Multiple sclerosis in Mexico: hospital cases at the National Institute of Neurology and Neurosurgery, Mexico City.

The frequency and clinical features of multiple sclerosis (MS) at the National Institute of Neurology and Neurosurgery in Mexico City for the period spanning 1984-1993 is presented. Hospital records of patients with clinically diagnosed MS were selected, the frequency and cumulative frequency of this diagnosis were determined and demographic information and clinical features were recorded. It was found that 70% of the patients were women, 25% were professionals, and 95% were of mixed race. The clinical features of our patients and their neuroimages were consistent with those of MS patients in other populations. Importantly, we found that the frequency of MS has almost doubled over the last 10 years. The reason for this phenomenon is discussed as resulting from better health screening, the availability of nuclear magnetic resonance imaging, and the cultural, demographic and dietary changes that have occurred due to the rapid urbanization of our country.