Faculty Bibliography

BACKGROUND:Only half of hypertensive adults achieve blood pressure (BP) control in the United States, and it is unclear how BP control rates may be improved most effectively and efficiently at the population level. OBJECTIVE:We sought to compare the potential effects of system-wide isolated improvements in medication adherence, visit frequency, and higher physician prescription rate on achieving BP control at 52 weeks. DESIGN/METHODS:We developed a Markov microsimulation model of patient-level, physician-level, and system-level processes involved in controlling hypertension with medications. The model is informed by data from national surveys, cohort studies and trials, and was validated against two multicenter clinical trials (ALLHAT and VALUE). SUBJECTS/METHODS:We studied a simulated, nationally representative cohort of patients with diagnosed but uncontrolled hypertension with a usual source of care. INTERVENTIONS/METHODS:We simulated a base case and improvements of 10 and 50%, and an ideal scenario for three modifiable parameters: visit frequency, treatment intensification, and medication adherence. Ideal scenarios were defined as 100% for treatment intensification and adherence, and return visits occurring within 4 weeks of an elevated office systolic BP. MAIN OUTCOME/RESULTS:BP control at 52 weeks of follow-up was examined. RESULTS:Among 25,000 hypothetical adult patients with uncontrolled hypertension (systolic BP ≥ 140 mmHg), only 18% achieved BP control after 52 weeks using base-case assumptions. With 10/50%/idealized enhancements in each isolated parameter, enhanced treatment intensification achieved the greatest BP control (19/23/71%), compared with enhanced visit frequency (19/21/35%) and medication adherence (19/23/26%). When all three processes were idealized, the model predicted a BP control rate of 95% at 52 weeks. CONCLUSION/CONCLUSIONS:Substantial improvements in BP control can only be achieved through major improvements in processes of care. Healthcare systems may achieve greater success by increasing the frequency of clinical encounters and improving physicians' prescribing behavior than by attempting to improve patient adherence to medications.

BACKGROUND:The American Heart Association (AHA) published guidelines for treatment of resistant hypertension in 2008 recommending use of thiazide diuretics (particularly chlorthalidone), aldosterone antagonists, and fixed-dose combination medications, but it is unclear the extent to which these guidelines are being followed. OBJECTIVE:To describe trends in physician use of recommended medications for resistant hypertension and assess variations in medication use based on geography, physician specialty and patient characteristics. DESIGN/METHODS:Cross-sectional analysis using the National Ambulatory Medical Care Survey from 2006 to 2010. STUDY SAMPLE/METHODS:We analyzed visits of hypertension patients to family physicians, general internists, and cardiologists. Resistant hypertension was defined as concurrent use of ≥ 4 classes of blood pressure (BP) medications or elevated BP despite the use of ≥ 3 medications. Pregnant patients and visits with diagnosed heart failure or end-stage renal disease were excluded. MAIN OUTCOME/RESULTS:Use of AHA-recommended medications for management of resistant hypertension. RESULTS:Of 19,500 patient visits with hypertension, 1,567 or 7.1 % CI (6.6-7.7 %) met criteria for resistant hypertension. Thiazide diuretic use was reported in 58.9 % of visits pre-guidelines vs. 54.8 % post-guidelines (p = 0.37). Use of aldosterone antagonists was low and also did not change significantly after guideline publication (3.1 % vs. 4.5 %, p = 0.27). Fixed-dose combinations use was 42.0 % before and 37 % after guideline publication (p = 0.29). Each 10-year increase in patient age was associated with lower thiazide use (OR 0.87, CI 0.77-0.97), as was presence of comorbid ischemic heart disease (OR 0.62, CI 0.41-0.94). Medication use did not vary by geography or physician specialty. CONCLUSION/CONCLUSIONS:Use of AHA-recommended medications for resistant hypertension remains low after publication of guidelines. Healthcare systems should encourage more frequent prescribing of these medications to improve care in this high-risk population.