Secular trends in cerebrovascular mortality.

Since 1950 a marked decrease in cerebrovascular mortality has occurred in most Western countries. To evaluate whether changes in the pharmacological treatment of hypertension, introduced during the period observed (1950-87), have influenced this downward trend the linear time-trends over the period considered were calculated. Mass treatment of hypertension at the population level started in the early 1970s. Before this period a marked decrease in cerebrovascular mortality had already occurred. Moreover, the linear time trends were highly significant over the whole period with several correlation coefficients of > 0.98. The decrease in cerebrovascular mortality can best be explained by a decreased salt and saturated fat intake in the populations considered. In several Eastern European countries cerebrovascular mortality has increased. This runs parallel with an increase in all-cause mortality and an increase in ischaemic heart disease mortality and can be explained by the high saturated fat intake of these populations. The data show that important changes in cerebrovascular mortality are also occurring in the older age groups, e.g. 70-74 and 80-84 years. Epidemiological data point towards nutrition as playing an important role in the evolution of cerebrovascular mortality over the period considered.