Blood Pressure Control in Hispanics in the Antihypertensive and Lipid-

lowering Treatment to Prevent Heart Attack Trial (ALLHAT)

Karen L. Margolis, Linda B. Piller, Charles E. Ford, Mario Henriquez, William C. Cushman, Paula T.

Einhorn, Pedro J. Colon, Sr., Donald G. Vidt, Rudell Christian, Nathan D. Wong, Jackson T. Wright, Jr.,

David C. Goff, Jr., for the ALLHAT Collaborative Research Group

Hypertension. 2007;50:854-861

ALLHAT

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From Bernard CheungFrom Bernard CheungOng, et al, Hypertension 2007Ong, et al, Hypertension 2007

Prevalence of Hypertension in U.S. byRace/Ethnicity: 1988-2004

Hypertension Awareness,Treatment and Control

  White Non-Hispanic

Mexican American

  NHANES II

1976-80

NHANES III

1988-91

HispHANES1982-4

NHANES III

1988-91

Aware 50 74 60 57

Treat 31 56 38 37

Control 10 30 19 21 

Changes in Hypertension Awareness, Treatment, and Control

• NHANES 2003-2004 – some improvement among Mexican-Americans, but disparities remain

BP Control

TotalAmong Treated Hypertensives

Mexican American 27% 57%

Non-Hispanic Black 29% 52%

Non-Hispanic White 35% 68%

Reasons for Racial and Ethnic Differences in BP Control?

• Lack of access to health care• Inability to afford medication• Other socioeconomic factors• Beliefs about hypertension• Language barriers• Poor MD-patient communication• Family influences• Diet• Metabolic risk factors• Other biological factors insufficient treatment or

resistance to treatment

6

AntihypertensiveTrial Design

• Randomized, double-blind, concurrently controlled practice-based clinical trial in 42,418 participants with hypertension comparing 4 commonly-used antihypertensive drugs.

• ALLHAT investigated whether there was a difference in fatal CHD & nonfatal MI (primary endpoint) among patients randomized to CCB, ACEI, or alpha-blocker compared to a thiazide-type diuretic.

• Step-up medications as needed for BP control.

ALLHAT

Secondary Outcomes

• All-cause mortality

• Stroke

• Combined CHD – nonfatal MI, CHD death, coronary revascularization, hospitalized angina

• Combined CVD – combined CHD, stroke, lower extremity revascularization, other treated angina, treated HF

• Other – renal (reciprocal serum creatinine, ESRD, estimated GFR), diabetes, and cancer

ALLHAT

Inclusion Criteria

Men and women aged > 55 years

Seated blood pressure (2 categories):

1) Treated for @ least 2 months (1-2 drugs).

2) Not on drugs or on drugs <2 months.

Additional risk factor or target organ damage.

ALLHAT

BP Eligibility Criteria

Lower Limit (mm Hg)

Upper Limit (mm Hg)

Status at Visit 1 and Visit 2 SBP DBP SBP DBP

On 1-2 drugs used for hypertension >= 2 months

Visit 1 Visit 2

---

---

---

---

160

180

100

110

On drugs for < 2 months or currently untreated

Visit 1 & Visit 2

140 90 180 110

SBP or DBP lower limit must be met at Visit 1 and Visit 2 SBP and DBP upper limit must be met at Visit 1 and Visit 2

ALLHAT

10

Doxazosin Arm Terminated Early

• Statistically significant 25% higher rate of major secondary endpoint, combined CVD outcomes (2-fold higher rate of heart failure and 20% higher risk of stroke)

• Futility of finding a significant difference for primary CHD outcome

ALLHAT

JAMA. 2000;1967-1975 & Hypertension. 2003;42:239-246.

Randomized Design of ALLHAT BP Trial

42,418

High-risk hypertensive patients

Consent / Randomize

Amlodipine

Chlorthalidone

Doxazosin

Lisinopril

Follow until death or end of study (4-8 years, mean 4.9 years)

ALLHAT

• 42,418 participants randomized (Feb. 1994 through Jan. 1998)

• After excluding doxazosin arm – 33,357– 3% Black Hispanic (BH)– 16% White Hispanic (WH)– 33% Black nonHispanic (BNH)– 48% White nonHispanic (WNH)

• 73% of Hispanics were from Puerto Rico

Study PopulationALLHAT

Treatment

• Access to high-quality hypertension care

• Study medications at no cost

• Required dosage titration and additional medications if SBP 140 or DBP 90 mmHg.

ALLHAT

AntihypertensiveTreatment Regimen

Step 1 Dose 1 Dose 2 Dose 3

Chlorthalidone 12.5 mg 12.5 mg 25 mg

Amlodipine 2.5 mg 5 mg 10 mg

Lisinopril 10 mg 20 mg 40 mg

Step 2

Reserpine 0.05 mg qd 0.1 mg qd 0.2 mg qd

Clonidine 0.1 mg bid 0.2 mg bid 0.3 mg bid

Atenolol 25 mg qd 50 mg qd 100 mg qd

Step 3

Hydralazine 25 mg bid 50 mg bid 100 mg bid

ALLHAT

Baseline Characteristics-1ALLHAT

BH WH BNH WNHSample Size 1,090 5,239 10,608 15,705Mean SBP/DBP 147/87 146/85 145/84 145/82Previous HT treatment, % 89 90 91 90Mean age, years 66 67 66 68Women, % 59 56 54 39Current smoking, % 19 18 26 21History of type II diabetes, %

39 40 40 32

ASCVD, % 45 45 45 59LVH by baseline ECG, % 3 2 6 2

Baseline Characteristics-2ALLHAT

BH WH BNH WNHSample Size 1,090 5,239 10,608 15,705Puerto Rican or USVI, % 87 70 0.1 0.1

Education, years 8 9 10 12Mean BMI, kg/m2 30 29 31 30S. Creatinine, mg/dL 1.0 0.9 1.1 1.0F. Glucose, mg/dL 126 128 127 119

Mean Systolic Blood Pressure

by Race and EthnicityALLHAT

Mean Diastolic Blood Pressure

by Race and EthnicityALLHAT

Blood Pressure ControlALLHAT

Number ofAntihypertensive MedicationsALLHAT

Participants withUncontrolled BP on 1 Medication –

Percentage Stepped UpALLHAT

Participants withUncontrolled BP on 2 Medications –

Percentage Stepped UpALLHAT

Relative Odds ofBP Control at Year 2Unadjusted Adjusted*

OR† 95% CI OR† 95% CI

Total

Black Hisp 1.05 0.89 – 1.24 1.04 0.86 – 1.25

White Hisp 1.17 1.09 – 1.27 1.20 1.10 – 1.31

Black nonHisp 0.70 0.66 – 0.74 0.73 0.69 – 0.78

Excluding PR/VI

Black Hisp 1.03 0.70 – 1.51 1.01 0.68 – 1.52

White Hisp 0.99 0.88 – 1.11 1.07 0.94 – 1.22

Black nonHisp 0.70 0.66 – 0.74 0.74 0.69 – 0.78* Adjusted for age, sex, race-ethnicity, history of diabetes, current smoking, history of ASCVD, BMI30 kg/m2, antihypertensive treatment prior to enrollment, baseline SBP, creatinine 1.5 mg/dL, LVH on ECG, treatment assignment.

† Compared with White non-Hispanic

ALLHAT

Summary - 1U.S. population 14.1% Hispanic/Latino in 2004

• Hispanic ALLHAT participants had equivalent or superior BP control compared with non-Hispanics– Equal access to care

– No-cost medications

• Also reported in INVEST

• Hispanic Blacks had slightly lower levels of BP control compared with Hispanic whites, similar BP control to non-Hispanic whites, and better BP control than non-Hispanic Blacks.

ALLHAT

Summary - 2• Compared with non-Hispanic whites, Hispanics less

likely to have health insurance or regular source of care, less likely to receive preventive services

– Linked to lower rates of BP screening and treatment in Hispanics

• Primary care clinics in Boston – Hispanic participants less likely to have meds intensified, but if intensified, equally likely to achieve BP control

THUS:

• Hispanic patients likely to face barriers to hypertension screening, initiation of therapy, and appropriate intensification of therapy.

ALLHAT

Conclusions• Low rate of BP control in US Hispanics not due to

biological factors.– Controlled in 2/3 of Hispanic ALLHAT participants

– Commonly-available medications, including thiazide-type diuretics

• Focus on improving:– Hypertension knowledge and awareness

– Doctor-patient communication

– Access to medical care

– Affordable medications

• BP control in Hispanic patients is an achievable goal and should therefore be declared a public health priority

ALLHATALLHAT

Reserve SlideReserve Slide

Summary - 3• Other explanations for better BP control among

Hispanic participants?

• Adherence to med may have been lower among Hispanics prior to randomization (slightly higher BP levels) – more Hispanics essentially “untreated”?

• Systematic bias in BP measurements

– 0 terminal digit preference associated with underestimates of BP, undertreatment of hypertension

– Relatively high frequency (24% for SBP at 1 year) – 42% in Hispanics vs 21% in non-Hispanics) – especially high in PR and USVI

– No evidence for systematic effort to inflate BP control rates

ALLHATALLHAT

Clinical Inertia• Failure to advance therapy despite suboptimal BP

control

• Reinforces need for effective methods to improve BP control through comprehensive programs

– Patients

– Providers

– Health care systems

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