The epidemiology of multiple sclerosis in Latin America and the Caribbean: a systematic review.

The incidence and prevalence of multiple sclerosis (MS) varies geographically as shown through extensive epidemiological studies performed mainly in developed countries. Nonetheless, scant data is available in Latin America and the Caribbean (LAC). The objective of this review is to assess epidemiological data of MS in LAC. We conducted a systematic review of published articles and gray literature from January 1995 to May 2011. Twenty-two studies met the inclusion criteria after full-text review. Incidence data were found in only three studies and ranged from 0.3 to 1.9 annual cases per 100,000 person-years. Prevalence was reported in 10 studies and ranged from 0.83 to 21.5 cases per 100,000 inhabitants. The most prevalent subtype of MS was the relapsing-remitting form (48% to 91% of the series). No data about mortality were found. This study showed low frequency for MS in LAC compared with North American and European countries. The role of environmental and genetic factors should be well studied, providing new insights about its etiology.