ISCHEMIC-HEART-DISEASE MORTALITY AMONG MEN IN NORWAY - REVERSAL OF URBAN-RURAL DIFFERENCE BETWEEN 1966 AND 1989

Objective - This study aimed to examine regional urban-rural differenc es in mortality from ischaemic heart disease, including sudden death o f unknown cause (IHD/SUD) in Norway from 1966-89, for men and women ag ed 30-69 years. Design - Analysis was based on vital statistics. Regio nal mortality rates were obtained by aggregating the 443 municipalitie s in Norway into urban, rural, and intermediate municipalities. Settin gs and subjects - Norway. Results - In 1966-70 the age adjusted IHD/SU D mortality in the age group 30-69 years was higher in urban than in r ural areas; for men by 31% (95% CI 27%, 36%) and for women by 28% (95% CI 19%, 36%). In 1986-89 the IHD/SUD mortality for men showed a rever sed urban-rural gradient: it was 8% (95% CI 2%, 13%) higher in rural t han in urban areas. The mortality rates for women were equal for both these aggregates. For men the results indicate that IHD/SUD mortality peaked first in urban municipalities and then, but at a lower level, i n rural areas. For women there was a substantial decline in IHD/SUD mo rtality between 1966 and 1989, but an actual peak could not be demonst rated in any of the three aggregates during the period. The decline in IHD/SUD mortality among women was steepest in urban municipalities an d least noticeable in rural municipalities, but the decline tapered of f towards the end of the study period. Conclusion - The results confir m a phase-shifted peak in IHD/SUD mortality, which began in towns and ended in rural areas, and provides clues to the main underlying factor s in the IHD epidemic at the population level.