[The influence of geographical background on the clinical and neurophysiological characteristics of patients with multiple sclerosis in Cuba].
BACKGROUND
Multiple sclerosis (MS) was first described by Charcot in 1868 and the first case in Cuba was reported in 1965. Prevalence rate is now considered to be about 10 cases/100,000 inhabitants. Cuba is an island that can be divided into three different geographical regions and a comparison of these areas is interesting because it is known that geographical features exert an influence on MS. Demographic differences are also present.


OBJECTIVE
The purpose of this study was to evaluate a sample of cases from the Western part of the country as regards their results on two important scales and the results of evoked potentials (EP), and to compare them with two samples of patients from the other two regions.


METHODS
The first sample was made up of 50 patients living in the western region; their diagnosis was confirmed, the scales were applied and the EP test was performed because of its high degree of sensitivity, objectivity and reproducibility. Results were then compared with the other two studies that had already been reported.


RESULTS
Most cases had a score of between 0.5 and 5.5 points on the EDSS and only 6% scored above 7.0 points. Patients with PP type MS obtained higher scores. More than half the cases had more than 80 points on the Scripps scale and the second largest group had between 61 and 80 points; the two progressive forms behaved in a similar manner. The most sensitive EP are visual, followed by somatosensory and, lastly, by brain stem auditory EP (BAEP). The vast majority of the results compared with the series from the central region and from Santiago de Cuba were similar, yet some significant differences were found: progression time is longer in the West, EDSS scores were higher in the primary progressive form in the East and the BAEP were less sensitive in the West.


CONCLUSIONS
Our findings correspond to those available from other countries around the world and it can be seen that some of the parameters differ between the three regions.
Instituto Nacional de Neurologia y Neurocirugia, La Habana, Cuba. erelido@infomed.sld.cu
E
E
Hernández-Valero
J A
JA
Cabrera-Gómez
D003462:Cuba / Q000453:epidemiology; D018450:Disease Progression; D005071:Evoked Potentials / Q000502:physiology*; D005843:Geography; D006801:Humans; D009103:Multiple Sclerosis / Q000175:diagnosis / Q000453:epidemiology* / Q000503:physiopathology*