[Descriptive epidemiology of neuromyelitis optica in the Caribbean basin].

INTRODUCTION: Data on epidemiology of neuromyelitis optica (NMO) remained scarce in the last century, but the recent development of diagnostic criteria now enables inclusion of both monophasic and relapsing NMO in epidemiologic studies. Given the rarity of NMO, multicentric studies are needed to confirm a presumed higher frequency in women and in populations of black/Asian ancestry. The Caribbean basin is a suitable area for collecting a large NMO cohort and to assess the prevalence, incidence, and mortality of this disorder.

PATIENTS AND METHODS: This population-based survey of the NMO spectrum in the French West Indies (FWI) and Cuba included 151 cases.

RESULTS: Ninety-eight patients (female/male ratio: 9.8) had NMO. Age of onset in NMO patients was 30.9 years. Mean annual incidence of NMO in the French West Indies for the period July 2002 to June 2007 was 0.20/100,000 inhabitants (IC 95% 0.05-0.35). Incidence rates were steady in the FWI during the 1992 to 2007 period. Decreasing mortality in the FWI during the 1992 to 2007 period explained the increasing prevalence which was 4.20/100,000 inhabitants (IC 95% 3.7-5.7) in June 2007. The prevalence of NMO in Cuba on November302004 was 0.52/100,000 inhabitants. (IC 95% 0.39-0.67). Prevalence rates did not differ significantly by ethnic group in Cuba, however, black Cubans exhibited the highest prevalence.

DISCUSSION: Epidemiologic studies on NMO in each population are needed to determine whether aggressive therapies can reduce the mortality of this devastating disorder.

CONCLUSION: In the Caribbean basin, NMO involves almost exclusively young women; the epidemiologic data confirm its predilection for populations of African ancestry. In the FWI, recent and aggressive therapy has lowered mortality but with an increase in the prevalence of NMO.