SOME EPIDEMIOLOGIC ASPECTS OF STROKE - MORTALITY MORBIDITY TRENDS, AGE, SEX, RACE, SOCIOECONOMIC-STATUS

Background and Purpose: The reasons for decreasing stroke mortality could be related to either decreasing incidence and/or improved prognosis. Thus far, secular trends of stroke have been analyzed either through mortality or morbidity data. This report examines both aspects simultaneously, on a nationwide basis, for the period 1968-1988. Methods: Mortality statistics were based on the Compressed Mortality File. Estimates of morbidity were based on the National Hospital Discharge Survey. The Area Resource File was used to obtain county-specific socioeconomic statistics. Results: The decline in stroke mortality continued through the 1970s and 1980s, whereas morbidity remained constant and possibly even increased. Mortality and morbidity rates were similar in both sexes, higher in blacks, and lower in other (primarily Asian) Americans. There was an inverse correlation between death rates and socioeconomic status, which was particularly marked in blacks. Temporal decline occurred in all strata. Conclusions: The observed decrease in stroke mortality rates results most probably from an improved survival rather than from a decline in incidence. The abundance of new drugs and screening programs may not have affected the overall morbidity of stroke, possibly because of inefficient treatment regimens.