Multiple sclerosis among Spanish-surnamed Californians.

The 2,500,000 Spanish-surnamed white Californians have an age-adjusted multiple sclerosis death rate of 0.27 per 100,000 based on 48 MS deaths from 1966 through 1975. This compares with a rate of 0.83 for other white Californians and 0.75 for all Californians, suggesting that the MS death rate in California is due to genetic or local environmental causes. However, the 620,000 foreign-born Spanish-surnamed white Califorians have the extremely low MS death rate of 0.07, which is one-sixth the rate of 0.42 for the 1.330,000 Spanish-surnamed whites born in California. These data, by contrast with the first set, seem to indicate that environmental factors associated with place of birth are of primary importance. These findings suggest that Spanish-Americans as a whole have an MS death rate that is among the lowest of all subpopulation in the United States and that they offer additional opportunities for studying the etiology of multiple sclerosis.