Trends in mortality from cerebrovascular disease in Italy, 1955-78.

Trends in age-specific and age-standardized death certification rates from all cerebrovascular diseases and various diagnostic subcategories in Italy during the period 1955-78 have been analysed. In both sexes, a decrease in excess of 25% was evident in the overall age-standardized cerebrovascular disease mortality. However, rates were roughly stable in males up to age 50 and in females up to age 45, and slightly but consistently increasing in the younger age groups (under 40), mostly in females. The largest downward trends were for both sexes in the 55 to 74 age groups, and the declines were more marked in females, averaging 3% per year. Since death certification is most reliable in the younger age groups and it is difficult to imagine any modification of risk factors which should affect mortality in later middle age but not in younger age groups, there is no obvious and simple interpretation of this pattern of trends. A comparison with similar trends in ischemic heart disease and other causes of death suggests that the decline in overall cerebrovascular disease mortality might be partially or largely artefactual, though a between-sexes comparison indicates that at least part of the decrease registered in females may well be real. The extent of the decline, however, has been almost certainly more limited in Italy than in most other Western countries. Only in the younger age group (30-34) did rates show a larger increase in females, which might be related to increased prevalence of cigarette smoking, or the use of oral contraceptives.