Geographic and racial patterns of preventable hospitalizations for hypertension: Medicare beneficiaries, 2004-2009.

OBJECTIVES: Hypertension as the primary reason for hospitalization is often used to indicate failure of the outpatient health-care system to prevent and control high blood pressure. Investigators have reported increased rates of these preventable hospitalizations for black people compared with white people; however, none have mapped them nationally by race.
METHODS: We used Medicare Part A data to estimate preventable hypertension hospitalizations from 2004-2009 using technical specifications published by the Agency for Healthcare Research and Quality. Rates per 100,000 beneficiaries were age- and sex-standardized to 2000 U.S. Census data. We mapped county-level rates by race and identified clusters of counties with extreme rates.
RESULTS: Black people had higher crude rates of these hospitalizations than white people for every year studied, and the test for an increasing linear time trend for the standardized rates was significant for both black and white people; that is, the gap between the races increased over time. For both races, clusters of high-rate counties occurred primarily in parts of Oklahoma, Texas, Southern Alabama, and Louisiana. High rates for white people were also found in parts of Appalachia. Large differences in rates among black and white people were found in a number of large urban areas and in parts of Florida and Alabama.
CONCLUSIONS: Racial disparities in preventable hospitalizations for hypertension persisted through 2009. The gap between black and white people is increasing, and these inequities exist unevenly across the country. Although this study was intended to be purely descriptive, future studies should use multivariate analyses to examine reasons for these unequal distributions.