Annual incidence, prevalence, and mortality of multiple sclerosis in white South-African-born and in white immigrants to South Africa.

Abstract

On settling in South Africa in 1947 I learned that multiple sclerosis (M.S.), or disseminated sclerosis as it was usually called, was thought to be uncommon among South Africans.I therefore proceeded with a study of all white patients diag- nosed as having this disease at the major South African hospitals and found that 14 out of 27 in whom the diagnosis could be accepted as probable in 1948 were immigrants from Europe, though immigrants were only 10% of the population at risk.Among the South-African born White population the disease was apparently uncommon.1 * This study was supported by Research Grants Nos.247-1-5 from the National Multiple Sclerosis Society, New York, U.S.A.t Eastern Cape Provincial Hospital, Port Elizabeth, South Africa.were immigrants to South Africa.There is also a high propor- tion of immigrants among the possible M.S. patients, 17 out of 38.Of the 158 South-African-born M.S. patients, 101 were English-speaking, and a higher proportion of these M.S. cases than of age-standardized controls, from a large market research survey of the population at risk, were first-generation South- African-born with both parents immigrants from Europe.2The difference between the actual number with both parents born in Europe (40 out of 101) and the "expected" number (23.5) is statistically significant (P<0.01).In a further 22 of the on 16