Cardiac mortality in Alaska's indigenous and non-Native residents.

Cardiac disease mortality in Alaska, from both ischaemic and rheumatic heart disease, is of interest given the high consumption of fish and high streptococcal disease rates in the indigenous population. Uniformly coded underlying cause-of-death data for the period 1979-1988, compared with that from 1955-1965, indicated that deaths from all cardiac diseases combined, have been increasing in Alaska Natives over the past 30 years. Recent mortality from all cardiac, ischaemic, and rheumatic heart diseases in Alaska Natives were 80%, 61%, and 202% of those corresponding levels in Alaskan whites, whose cardiac mortality closely profiles US whites. Alaska Native men aged 30-45 years had higher overall mortality rates for cardiac diseases than did whites because of higher mortality rates of rheumatic heart disease and cardiomyopathy. Elderly Alaska Native men had lower rates than whites, reflecting less ischaemic heart disease mortality. The lowest levels of ischaemic heart disease mortality, less than one-third that of US whites, occurred in Alaskan Eskimos who lived in an area with documented patterns of high salmon consumption by individuals with high blood concentrations of omega-3 fatty acids. Elevated mortality from non-ischaemic heart disease and previously documented genetic markers suggest associations deserving further study.