Introduction:
Hypertensive black patients have the lowest rates of blood pressure (BP) control. It is unknown to what extent variation in healthcare processes like treatment intensification (TI) and missed visits explain this disparity.
Hypothesis:
We hypothesized there would be no racial differences in TI but missed visits would be more frequent among black patients and mediate a sizable percentage of BP control disparities.
Methods:
We used a structural equation multivariate regression model to estimate the likelihood of BP control (BP<140/90 mm Hg) in black vs. white hypertensive patients, mediated by TI and missed visits. We included 6,556 patients who had diagnosis of hypertension and at least one clinic visit with uncontrolled BP (≥140/90 mm Hg) in 12 safety-net clinics in San Francisco from 2015-2017.We used the standard-based method (SBM), which is predictive of BP control, to calculate TI (dose increase or medication addition). We measured missed visits as the number of “no-shows” in the four weeks after an uncontrolled BP. BP control was defined based on the most recent BP as of Nov 15, 2017. The model adjusted for gender, age, first recorded BP between Jan 2015 and Nov 2017, visit frequency, and diagnosis of diabetes.
Results:
The mean (SD) age was 57.0 (11.2), 41% were female, and 44% were black. Compared to whites, blacks had more missed opportunities for TI (β=-0.02, p<0.001) and missed more visits (β=0.37, p<0.001). After accounting for these differences, black patients remained less likely than whites to achieve BP control (β=0.16, OR=0.85, 95% CI=0.76-0.95). The indirect effect of decreased TI and missed visits accounted for 22% and 13% of the total effect of black race on BP control, respectively (Figure).
Conclusion:
Racial inequities in treatment intensification may be responsible for over 20 percent of racial disparities in hypertension. Efforts to ensure more equitable treatment intensification may reduce black-white disparities in BP control.