Clinical Characteristic of Patients with Uncontrolled, Potentially Under-treated and Apparent Treatment Resistant Hypertension: NHANES 19882008.

1Brent M. Egan, 1Yumin Zhao, 1,2R. Neal Axon, 1Walter A. Brzezinski, 3Keith C. Ferdinand 1Medical University of South Carolina and 2Ralph H. Johnson VAMC, Charleston, SC; 3Emory University, Atlanta, GA

Abstract. Background. Defining the characteristics of uncontrolled hypertensive patients may facilitate efforts to improve blood pressure (BP) control.

Methods: Subjects included 13,375 hypertensive adults from National Health and Nutrition Examination Surveys (NHANES) 1988 – 2008. Uncontrolled hypertension was defined as BP 140/90 mmHg and apparent treatment resistant (aTRH) if the patient reported taking 3 antihypertensive medications. Framingham 10-year coronary risk (FCR) was calculated. Multivariate regression was used to identify predictors of untreated, treated uncontrolled, and aTRH.

Results: The majority of uncontrolled hypertensives were untreated across surveys. Multivariate predictors of untreated hypertension in all three NHANES survey periods, i.e., consistent, included male sex (odds ratio [OR} 2.262.73, 95% confidence intervals [{CI}1.863.51]), infrequent healthcare (01 visits/yr) OR (4.664.95 , 95% CI [3.116.94]), body mass index <25 kg/m2 and <Stage 3 chronic kidney disease ([CKD], (OR 1.672.28, 95% CI [1.103.66] and FCR <10% (OR 7.658.61 [4.78 12.26]).

Most treated, uncontrolled patients reported taking 12 BP medications. Predictors of treated, uncontrolled hypertension among all controlled and uncontrolled subjects that reported taking 1–2 BP medis included increasing age (OR 1.191.30, 95% CI [1.061.42]/10 yrs), black race/ethnicity (OR 1.431.47, 95% CI [1.131.85]), and FCR >20% (OR 1.812.93, 95% CI [1.273.86]).

The percentage of uncontrolled hypertensives with aTRH increased over time (15.9% vs. 28.0%, p<0.01). Predictors of aTRH included obesity (OR 2.04, 95% CI [1.173.53], CKD (OR 2.52, 95% CI [1.75 3.62]), and FCR >20% (OR 4.29, 95% CI [1.95 9.42]) with age and black race/ethnicity significant in 2005 2008.

Conclusions: Strategies to increase healthcare use by people that are disproportionately male, lean and low 10-yr FCR could improve hypertension treatment and control. Targeted strategies are needed to offset projected increases in uncontrolled (under)treated (1–2 BP meds) and aTRH (≥3 BP meds) given population health trends to older age, more ethnic minorities, a higher prevalence of obesity complicated by CKD, and CHD risk equivalence.

BACKGROUND. Defining characteristics of uncontrolled hypertensive patients that are untreated, under-treated and treatment resistant may facilitate efforts to improve blood pressure (BP) control.

OBJECTIVES. Define clinical predictors of uncontrolled hypertension that is (a) untreated (b) potentially under-treated (1–2 BP meds) and apparent treatment resistant ([aTRH] ≥3 meds)

METHODS. Subjects included 13,375 hypertensive adults from NHANES 1988 to 2008. Uncontrolled hypertension was defined as BP 140/90. Framingham 10-year coronary risk (FCR) was calculated. Multivariate logistic regression analysis was used to identify independent clinical predictors of untreated (0 BP meds), ‘under-treated’ (1–2 BP meds), and aTRH (≥3 BP meds).

RESULTS. The number of BP meds reportedly taken by hypertensives in 3 NHANES periods are shown in Figure 1. The majority of uncontrolled hypertensives were untreated across surveys. Multivariate predictors of untreated hypertension in all three NHANES survey periods (Figure 2), i.e., consistent, included male sex, infrequent (01) healthcare visits/yr, body mass index <25 kg/m2, <Stage 3 chronic kidney disease (CKD), and FCR <10%.

Most treated, uncontrolled patients reported taking 12 BP meds. Predictors of treated, uncontrolled hypertension across surveys are depicted in Figure 3. Consistent predictors of ‘under-treated’ hypertension included increasing age, black race, and FCR >20%.

SUMMARY AND CONCLUSIONS. Untreated, ‘under-treated’, and aTRH patients have consistent distinguishing clinical characteristics that could inform strategies to decrease untreated hypertension, reduce therapeutic inertia in under-treated patients, and enhance therapeutic efficiency in aTRH.

Given an aging population with complicated, high-risk obesity, the prevalence of ‘under-treated’ and aTRH is likely to increase in the absence of a data-guided response.

Published in Circulation. 2011; 124:1046–1058.

RESULTS (continued) The percentage of uncontrolled hypertensives with aTRH increased over time (15.9% vs. 28.0%, p<0.01). Consistent independent clinical predictors of aTRH across surveys included obesity (Figure 4), CKD, and FCR >20%. Increasing age and black race were independently predictive of aTRH in 20052008.

Fig 1. # of BP Meds Reportedly Taken by Hypertensive Patients in the 3 NHANES periods.

Fig 2. Independent Clinical Predictors of Untreated Hypertension in 3 NHANES. Periods (multivariate logistic regression analysis)

Fig 3. Independent Clinical Predictors of Uncontrolled among Treated Hypertension in 3 NHANES. Periods (multivariate logistic regression analysis)

Fig 4. Independent Clinical Predictors of TRH among Uncontrolled Hypertension in 3 NHANES. Periods (multivariate logistic regression analysis)