CHANGES IN THE GEOGRAPHIC PATTERN OF STROKE MORTALITY IN THE UNITED-STATES, 1962 TO 1988

Background and Purpose The factors that contribute to the Stroke Belt- a concentration of high stroke mortality rates in the southeastern Uni ted States-remain unidentified. Previous hypotheses that focused on ph ysical properties of the area have not been confirmed. This study desc ribes changes in the locations of areas with the highest rates of stro ke mortality and the implications for new hypotheses regarding the Str oke Belt. Methods We calculated annual, age-adjusted stroke mortality rates for black women, black men, white women, and white men for the y ears 1962 to 1988 using a three-piece log-linear regression model. Map s were produced with the state economic area (SEA) as the unit of anal ysis. The baseline Stroke Belt was defined as the area with the larges t concentration of high-quintile SEAs in 1962. Results The concentrati on of high-rate SEAs tended to shift away from the Piedmont region of the Southeast and toward the Mississippi River valley. For example, wh ereas among black women in 1962, 72% of SEAs in the baseline Stroke Be lt were in the highest quintile, by 1988 this percentage had dropped t o 48%. Similar patterns were observed for the other race/sex groups. C onclusions Temporal changes in the location of areas with the highest stroke mortality rates suggest that new hypotheses for understanding t he geographic pattern of stroke mortality should consider temporal tre nds in a variety of medical, socioeconomic, and behavioral factors.