Racial disparities in hypertension control, but not treatment intensification.

BACKGROUND: Racial disparities in hypertension control are well documented, yet the contribution of providers to these disparities remains unclear. The objective of this study was to examine whether provider management of uncontrolled hypertension differed by patient race.
METHODS: In a retrospective cohort of 16,881 hypertensive adults in six academic primary care practices from 1/2004 to 12/2006, we evaluated hypertension control in black vs. white patients according to expert guidelines and, among those with uncontrolled hypertension, whether antihypertensive drugs were intensified by providers. Generalized estimating equations accounted for clustering and adjusted sequentially and additively for patient, provider, and practice characteristics, as well as health-care utilization and antihypertensive medication potency.
RESULTS: Black patients' visits (55.5% of 132,730 visits) had a higher unadjusted odds (1.63, 95% confidence interval (CI) 1.57-1.69) of uncontrolled hypertension than white patients' visits; the fully adjusted odds ratio remained significant (1.40, CI 1.33-1.48, P < 0.001). Among 66,327 visits with uncontrolled hypertension, no intensification of antihypertensive drugs was less likely for blacks' visits before adjustment (0.80, CI 0.76-0.83, P < 0.001) but moderated in the fully adjusted model (adjusted odds ratio 0.93, CI 0.87-0.99, P < 0.05) compared with whites' visits. Accounting for provider race, intensification was more likely at black patients' visits compared with white patients' visits.
CONCLUSIONS: In our study, black patients had poorer hypertension control, and providers were more likely to intensify antihypertensive drugs at visits of black compared with white patients as appropriate. These data suggest that more research is needed to understand racial disparities in hypertension control.