Epidemiology of multiple sclerosis in the Canary Islands (Spain) -: A study on the island of La Palma

Objective To determine the prevalence of multiple sclerosis (MS) on the Island of La Palma, Canary Islands, Spain. Methods A population-based transverse study was carried out on the Island of La Palma (population: 81,507), from 1995 to 1998. The 15 December 1998 was established as prevalence day. Sources of information were periodically obtained from case records from public primary care centres, private hospitals, private centres, magnetic resonance units and others. In accordance with the Poser criteria all cases of definite or probable MS were included. Results 34 cases of MS were found on prevalence day (9 male and 25 female): 32 cases were clinically definite and 2 were clinically probable MS. Crude prevalence was 42/100,000. Incidence during time of study was 2.25/100,000. Conclusions The island of La Palma could be considered as an area of medium-high risk, the risk being higher than that expected because of the geographical latitude of the island. This study confirms the hypothesis of the high prevalence of MS in Spain. We have not found significant clinical differences in MS patients from those in other studies.