Secular trend of mortality from cerebral infarction and cerebral hemorrhage in Taiwan, 1974-1988.

BACKGROUND AND PURPOSE Pathological patterns of stroke are different in various races, with the predominant stroke type in the Chinese being intracerebral hemorrhage. A total of 31,078 deaths from cerebral infarction and 77,773 deaths from cerebral hemorrhage in Taiwan were reported for groups of subjects aged 40-79 years during the period 1974-1988 to elucidate their secular trends. METHODS Vital statistics and demographic data were collected for analyzing the truncated age-adjusted mortality rates. Poisson regression analysis was used to estimate the relative risk and 95% confidence interval. RESULTS The mortality rates for cerebral hemorrhage were greater than those for cerebral infarction. The mortality rates increased exponentially with age for both subtypes. The decline in age-specific mortality for the period 1974-1983 was much more striking for cerebral hemorrhage than for cerebral infarction. Mortality from cerebral infarction and hemorrhage increased with age for all birth cohorts except the cerebral hemorrhage mortality of the oldest cohort. Male/female ratios for both cerebral infarction and hemorrhage were greater in the younger age groups. The cerebral hemorrhage/infarction ratio during the period 1984-1988 was highest for the younger age groups and lowest for the oldest age groups. CONCLUSIONS The different secular trends of mortality from cerebral infarction and hemorrhage imply that these two patterns of stroke may be associated with some different risk factors.