Assessing the Risk of Stroke in Florida By Geographical Region

BACKGROUND:   Stroke is the fourth leading cause of death in Florida. Identifying geographic areas with significantly high risks of stroke is important for informing public health prevention efforts.  Age-adjusted stroke hospitalization/mortality data have been mapped historically in Florida, but statistical analyses to determine if rates in certain areas are significantly higher than other areas have not been conducted.  This study investigated how geographic location impacts the risk of stroke in Florida, and identified areas with statistically higher rates of stroke hospitalizations and mortality.

METHODS:   Stroke hospitalization/mortality data from 1992-2012 was obtained from the Agency for Health Care Administration, for cases with stroke as the primary discharge diagnosis or underlying cause of death. ArcGIS 10 was used to develop choropleth maps, and assess disparities. Global Moran’s I was used to detect clustering of both hospitalization/mortality rates.  Additionally, local indicators of spatial association (LISA) and spatial scan statistics were used to identify the locations of stroke hotspots. 

RESULTS:   There were 196,923 stroke deaths and 1,463,524 hospitalizations during this time. Moran’s I for stroke mortality was significant for all years, however hospitalizations were not. High rate clusters for mortality consistently occurred in the northern region “stroke belt and similar patterns of low risk clusters occurred in the south.

CONCLUSIONS:   Stroke morbidity/mortality significantly impacts the health of many Floridians.  Stroke disproportionately impacts certain populations more than others. Public health officials should continue to identify areas and populations with higher risks for stroke and related risk factors.  These findings can be used to help inform public health efforts and policies.