Pulse pressure changes with six classes of antihypertensive agents in a randomized, controlled trial

Pulse pressure has been more strongly associated with cardiovascular outcomes, especially myocardial infarction and heart failure, than has systolic, diastolic, or mean arterial pressure in a variety of populations. Little is known, however, of the comparative effects of various classes of antihypertensive agents on pulse pressure. In retrospective analyses of the Veterans Affairs Single-Drug Therapy for Hypertension Study, we compared changes in pulse pressure with 6 classes of antihypertensive agents: 1292 men with diastolic blood pressure of 95 to 109 mm Hg on placebo were randomized to receive hydrochlorothiazide, atenolol, captopril, clonidine, diltiazem, prazosin, or placebo. Drug doses were titrated to achieve a goal diastolic blood pressure of <90 mm Hg during a 4- to 8-week medication titration phase. Pulse pressure change (placebo subtracted) was assessed from baseline to the end of the 3-month titration and 1-year maintenance. Mean baseline systolic, diastolic, and pulse pressures were 152, 99, and 53 mm Hg, respectively. Reductions in pulse pressure during titration were greater (P<0.001) with clonidine (6.7 mm Hg) and hydrochlorothiazide (6.2 mm Hg) than with captopril (2.5 mm Hg), diltiazem (1.6 mm Hg), and atenolol (1.4 mm Hg); reduction with prazosin (3.9 mm Hg) was similar to all but clonidine. After 1 year, pulse pressure was reduced significantly more (P<0.001) with hydrochlorothiazide (8.6 mm Hg) than with captopril and atenolol (4.1 mm Hg with both); clonidine (6.3 mm Hg), diltiazem (5.5 mm Hg), and prazosin (5.0 mm Hg) were intermediate. These data show that classes of antihypertensive agents differ in their ability to reduce pulse pressure. Whether these differences affect rates of cardiovascular events remains to be determined.

Ventricular and myocardial function following treatment of hypertension

This study assesses and evaluates left ventricular (LV) contractile function after treatment of hypertension, with an emphasis on LV midwall mechanics. Although prior studies have assessed cardiac function after hypertension treatment, none has performed an analysis of LV midwall mechanics. The Veterans Affairs Study of monotherapy in hypertension was a study large enough to permit analysis of midwall mechanics across a wide spectrum of mass changes accompanying hypertension treatment. LV chamber function was assessed by computing fractional shortening at the endocardial surface; LV midwall shortening was used to define myocardial function. Both shortening indexes were related to end-systolic circumferential stress in the entire population by partitioning values of mass and relative wall thickness changes. Two hundred sixty-eight patients were studied at baseline and again after a 1- or 2-year period. In the entire group, there was no significant change in circumferential shortening either at the endocardium (38 +/- 8% at baseline vs 37 +/- 7% at follow up, p = 0.29) or in shortening at the midwall (20 +/- 3% vs 20 +/- 3%, p = 0.53). However, 83 patients had a reduction in relative wall thickness and an increase in midwall shortening. The change in midwall shortening was significantly related to changes in relative wall thickness (r = -0.53, p = 0.0001). Thus, reductions in LV mass associated with antihypertensive therapy are generally not accompanied by a decrement in LV chamber or myocardial function. Improvement in midwall shortening is more closely related to normalization of LV geometry than to reduction in LV mass.

Placebo-associated blood pressure response and adverse effects in the treatment of hypertension: observations from a Department of Veterans Affairs Cooperative Study

BACKGROUND

The use of placebo in clinical trials has been vigorously debated. Placebo control may be useful in disease states, such as stage 1 and stage 2 hypertension as defined by the Sixth Report of the Joint National Committee on Detection, Evaluation and Treatment of High Blood Pressure (JNC VI), in which response rates for placebo are high or close to response rates for effective therapies, or when established interventions have significant adverse effects.

OBJECTIVE

To compare rates for the control of blood pressure and adverse effects of placebo vs active treatment in patients with stage 1 and stage 2 hypertension.

METHODS

This study is a randomized controlled trial evaluating the blood pressure response and adverse effects of placebo vs 6 active treatments administered in 15 Veterans Affairs hypertension centers. The 1292 subjects of the Veterans Affairs Cooperative Study receiving single-drug therapy for hypertension were randomly allocated to receive treatment with 1 of 6 active drugs (n= 1105) or placebo (n=187). Treatment success was defined as maintaining a diastolic blood pressure of less than 95 mm Hg for at least 1 year. We compared treatment success rates for the control of blood pressure and adverse effects of placebo vs active treatment. Using the Kaplan-Meier method, we also compared rates of discontinuation from placebo vs active drug treatment over time as a result of adverse drug effects and blood pressure exceeding safety limits.

RESULTS

At the end of the titration phase, 58 patients who were treated with placebo (31%) achieved a goal diastolic blood pressure lower than 90 mm Hg and 57 (30%) achieved success at 1 year. Older white patients who received placebo had a success rate of 38% vs 23% to 27% for the other age-race subgroups. The rates of discontinuation as a result of adverse drug effects were 13% for patients receiving placebo vs 12% for patients receiving active treatment (P=.40). The rates of discontinuation for blood pressure being too high were 14% for patients receiving placebo vs 7% for patients receiving active treatment (P=.01).

CONCLUSIONS

Placebo control provides an important benchmark for both efficacy and adverse effects. It continues to have an appropriate place in certain therapeutic trials, particularly those involving the treatment of stage 1 and stage 2 hypertension.

Regional and racial differences in response to antihypertensive medication use in a randomized controlled trial of men with hypertension in the United States. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

BACKGROUND

Stroke incidence and mortality rates are higher in the southeastern region of the United States, which is called the "Stroke Belt." We compared the response to antihypertensive medication use in patients from different US regions.

METHODS

The short-term and 1-year efficacy of the antihypertensive medications hydrochlorothiazide, atenolol, diltiazem hydrochloride (sustained release), captopril, prazosin hydrochloride, and clonidine was compared by US region in a randomized controlled trial of 1,105 men with hypertension from 15 US Veterans Affairs medical centers.

RESULTS

Compared with patients outside the Stroke Belt, patients inside the Stroke Belt achieved significantly lower treatment success rates of diastolic blood pressure control at 1 year with hydrochlorothiazide (63% vs 41%), atenolol (62% vs 46%), captopril (60% vs 30%), and clonidine (69% vs 43%); there were no differences in treatment success rates with diltiazem (70% vs 71%) or prazosin (54% vs 53%). When controlling for race, patients inside the Stroke Belt had significantly lower treatment success rates with hydrochlorothiazide (P = .003) and clonidine (P = .003), and the lower success rate with atenolol approached significance (P = .15). Regardless of region, blacks were less likely than whites to achieve treatment success with atenolol (P = .02) or prazosin (P = .03) and more likely with diltiazem (P = .05). There was a trend for blacks residing inside the Stroke Belt to have a lower treatment success rate than other race-region groups when treated with captopril (P = .07). Many regional and racial differences in diet, lifestyle, and other characteristics were observed. After adjustment for these characteristics by regression analysis, the effect of residing inside the Stroke Belt remained for captopril (P = .01) and clonidine (P = .01) and approached significance for hydrochlorothiazide (P = .10).

CONCLUSIONS

Hypertension in patients residing inside the Stroke Belt responded less to the use of several antihypertensive medications and important differences were shown in a number of characteristics that may affect the control of blood pressure, compared with patients residing outside the Stroke Belt.

Reducing the risk of malpractice claims

Many physicians will be sued for malpractice at some time during their careers. Risk of litigation can be reduced by adopting practices that include keeping thorough medical records, educating office personnel, and fostering good patient-physician relationships. The last is important because patients who view their physicians as caring tend not to sue even if an adverse outcome occurs.

Accessing data from external centralized sources to enhance analysis of a completed clinical trial

After the data collection phase of a clinical trial has been completed, new hypotheses may surface which require additional data before they can be tested. In the Veterans Affairs Cooperative Study on Single Drug Therapy of Hypertension, we investigated the relationship between location of the participating center, race and ability to control blood pressure. The analysis indicated poorer blood pressure control among sites located in the "stroke belt" (southeastern United States), especially among African-Americans. We sought to determine whether the effect was attributable to socioeconomic patterns; however, income data were not collected as part of the original study. Therefore, we accessed centralized data bases to obtain zipcode-level income information for the randomized study patients. This approach yielded estimates of income data for 94.3% of the patients and compared favorably to data acquisition rates for variables which were collected prospectively in the study.

Clinical presentation and management of patients with uncontrolled, severe hypertension: results from a public teaching hospital

CONTEXT

There is relatively little data available on the management of patients with severe, uncomplicated hypertension and severe hypertension with stable hypertensive complications.

OBJECTIVE

To determine the incidence, clinical features, acute management, and clinical course of severe, uncomplicated hypertension and severe hypertension with stable hypertensive complications presenting for emergency department care in a large public teaching hospital.

DESIGN

Chart survey of consecutive emergency department visits.

PATIENTS

Ninety-one of 2898 consecutive visits to a public teaching hospital emergency department were specifically for severe, uncomplicated hypertension.

RESULTS

Of 2898 consecutive medical emergency department visits, there were 142 (4.9%) patient visits specifically for systolic blood pressure (SBP) > or =220 mm Hg or diastolic blood pressure (DBP) > or =120 mm Hg. Ninety-one of the 142 patient visits were for severe hypertension in the absence of acute target organ impact or neuroretinopathy. Eighty-nine patients received acute drug therapy. Twenty-nine patients received two drugs, and 15 received three drugs. Sixty-eight patients (75%) received clonidine, and 15 (16.5%) received short-acting nifedipine despite widely published concerns about the safety of this practice. We found a wide variability of blood pressure response to treatment. The average decline in SBP was 50+/-31 mm Hg and the average decline of DBP was 34+/-20 mm Hg over 4.2+/-2.9 h. Forty-two patients (46%) had the SBP reduced to less than 160 mm Hg, and 46 patients (50%) the DBP to less than 100 mm Hg. Long-term management and follow-up were suboptimal. Of 74 patients discharged from the emergency room, 22 patients (30%) returned because of uncontrolled hypertension within an average of 33+/-28 days, 10 patients with hypertensive complications.

CONCLUSIONS

Severe hypertension continues to present an important and common problem. Physicians appear to place a strong emphasis on acute lowering of the blood pressure to near-normal levels. Patients are frequently lost to follow-up and have a very high rate of recurrent emergency department visits and hypertensive complications. This study points to a need for detailed, specific practice guidelines and comprehensive disease management protocols for severe, uncomplicated hypertension.

Diuretics and beta-blockers do not have adverse effects at 1 year on plasma lipid and lipoprotein profiles in men with hypertension. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

BACKGROUND

Concern based on the reported short-term adverse effects of antihypertensive agents on plasma lipid and lipoprotein profiles (PLPPs) has complicated the therapy for hypertension.

OBJECTIVE

To compare the long-term (1-year) effects of 6 different antihypertensive drugs and placebo on PLPPs in a multicenter, randomized, double-blind, parallel-group clinical trial in 15 US Veterans Affairs medical centers.

PATIENTS AND METHODS

A total of 1292 ambulatory men, 21 years or older, with diastolic blood pressures (DBPs) ranging from 95 to 109 mm Hg taking placebo were randomized to receive placebo or 1 of 6 antihypertensive drugs: hydrochlorothiazide, atenolol, captopril, clonidine, diltiazem, or prazosin. After drug titration, patients with a DBP of less than 90 mm Hg were followed up for 1 year. Plasma lipids and lipoprotein profiles were determined at baseline, after initial titration, and at 1 year.

RESULTS

After 8 weeks on a regimen of hydrochlorothiazide, increases of 3.3 mg/dL (0.09 mmol/L) in total cholesterol and 2.7 mg/dL in apolipoprotein B were significantly different (P< or =.05) from decreases of 9.3 mg/dL in total cholesterol and 5.4 mg/dL in ApoB levels while receiving prazosin but not from placebo. Patients achieving positive DBP control using hydrochlorothiazide (responders) showed no adverse changes in PLPPs, whereas nonresponders exhibited increases in triglycerides, total cholesterol, and low-density lipoprotein cholesterol levels. Plasma lipids and lipoprotein profiles did not change significantly among treatment groups after 1 year except for minor decreases in high-density lipoprotein 2 levels using hydrochlorothiazide, clonidine, and atenolol.

CONCLUSIONS

None of these 6 antihypertensive drugs has any long-term adverse effects on PLPPs and, therefore, may be safely prescribed. Previously reported short-term adverse effects from using hydrochlorothiazide are limited to nonresponders.

Effects of antihypertensive single-drug therapy on heart rate. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

Heart rate increasingly is being recognized either as an independent risk factor for a wide variety of cardiovascular disorders or as a surrogate marker for them. We analyzed the changes in heart rate associated with antihypertensive therapy with six drugs and placebo from the VA Cooperative Study on Single-Drug Therapy. These results were published previously (American Journal of Hypertension 1998;11:597-601). This paper provides a summary of the earlier publication with the addition of three figures not previously published. Atenolol had the greatest effect on heart rate reduction, followed by clonidine and diltiazem-SR. Hydrochlorothiazide and captopril were associated with small reductions in heart rate over time, whereas prazosin increased heart rate. Patients whose blood pressure was controlled by placebo had a 3.1 beats/min reduction of heart rate at 2 years. When the baseline heart rate was 65 beats/min or less, all drugs increased the heart rate except for atenolol, which further reduced it. Although it is clear that each of the six drugs used in our study had a different effect on heart rate, we cannot state that drug-induced reduction in heart rate per se confers a decrease in cardiovascular risk.

Age-race subgroup compared with renin profile as predictors of blood pressure response to antihypertensive therapy. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

CONTEXT

Renin profiling and age-race subgroup may help select single-drug therapy for stage 1 and stage 2 hypertension.

OBJECTIVE

To compare the plasma renin profiling and age-race subgroup methods as predictors of response to single-drug therapy in men with stage 1 and 2 hypertension as defined by the Joint National Committee on Prevention, Detection, Evaluation and Treatment of High Blood Pressure.

DESIGN

The Veterans Affairs Cooperative Study on Single-Drug Therapy of Hypertension, a randomized controlled trial.

SETTING

Fifteen Veterans Affairs hypertension centers.

PATIENTS

A total of 1105 ambulatory men with entry diastolic blood pressure (DBP) of 95 to 109 mm Hg, of whom 1031 had valid plasma and urine samples for renin profiling.

INTERVENTIONS

Randomization to 1 of 6 antihypertensive drugs: hydrochlorothiazide, atenolol, captopril, clonidine, diltiazem (sustained release), or prazosin.

MAIN OUTCOME MEASURE

Treatment response as assessed by percentage achieving goal DBP (<90 mm Hg) in response to a single drug that corresponded to patients' renin profile vs a single drug that corresponded to patients' age-race subgroup.

RESULTS

Clonidine and diltiazem had consistent response rates regardless of renin profile (76%, 67%, and 80% for low, medium, and high renin, respectively, for clonidine and 83%, 82%, and 83%, respectively, for diltiazem for patients with baseline DBP of 95-99 mm Hg). Hydrochlorothiazide and prazosin were best in low- and medium-renin profiles; captopril was best in medium- and high-renin profiles (low-, medium-, and high-renin response rates were 82%, 78%, and 14%, respectively, for hydrochlorothiazide; 88%, 67%, and 40%, respectively, for prazosin; and 51%, 83%, and 100%, respectively, for captopril for patients with baseline DBP of 95-99 mm Hg). Response rates for patients with baseline DBP of 95 to 99 mm Hg by age-race subgroup ranged from 70% for clonidine to 90% for prazosin for younger black men, from 50% for captopril to 97% for diltiazem for older black men, from 70% for hydrochlorothiazide to 92% for atenolol for younger white men, and from 84% for hydrochlorothiazide to 95% for diltiazem for older white men. Patients with a correct treatment for their renin profile but incorrect for age-race subgroup had a response rate of 58.7%; patients with an incorrect treatment for their renin profile but correct for age-race subgroup had a response rate of 63.1% (P = .30). After controlling for DBP and interactions with treatment group, age-race subgroup (P<.001) significantly predicted response to single-drug therapy, whereas renin profile was of borderline significance (P= .05).

CONCLUSIONS

In these men with stage 1 and stage 2 hypertension, therapeutic responses were consistent with baseline renin profile, but age-race subgroup was a better predictor of response.

Will angiotensin converting enzyme genotype, receptor mutation identification, and other miracles of molecular biology permit reduction of NNT?

Severe forms of hypertension demand treatment because they have a high incidence of morbidity and mortality that can be reduced by antihypertensive therapy. Stage 1-2 hypertension has a low morbidity and mortality; short-term benefits of treatment are harder to document. Managed care organizations know that members have a high turnover rate, so they are less interested in costly mass treatment to prevent a few future events. Stage 1-2 hypertension causes the vast majority of morbid events simply because a low incidence in a large population exceeds the lower absolute number of events in a small population with a high incidence. We must focus our efforts and resources on hypertensives at highest risk and thereby reduce the number needed to treat for 5 years (NNT) to avoid a morbid event. Obvious risks include hypertension severity, existing target organ damage, and concomitant diseases. Clues to the genetic etiology of primary hypertension are less obvious. DD genotype for angiotensin-converting enzyme (ACE) is associated with more left ventricular hypertrophy and greater risk for cardiovascular morbid events. Some genotypes of nitric oxide synthetase are associated with less effective production of NO and achieve less arterial vasodilation in response to stimuli. Many receptors have mutations that make them more or less functionally appropriate. Understanding these genetic factors may permit us in the future to focus appropriate drug therapy on the population most likely to benefit, thereby reducing NNT.

Effect of single-drug therapy on reduction of left atrial size in mild to moderate hypertension: comparison of six antihypertensive agents

BACKGROUND

Cardiac effects of hypertension include increased left ventricular (LV) mass and LV hypertrophy, as well as increased left atrial size, a predictor of stroke and atrial fibrillation. Although literature on reduction of LV mass with antihypertensive therapy is extensive, little information is available on effects of treatment on left atrial size.

METHODS AND RESULTS

Patients with mild to moderate hypertension (diastolic blood pressure 95 to 109 mm Hg) were randomly allocated to treatment with atenolol, captopril, clonidine, diltiazem, hydrochlorothiazide, or prazosin in a double-masked trial. Two-dimensional targeted M-mode echocardiography was used to assess left atrial size and LV mass at baseline, 8 weeks, and 1 and 2 years. Longitudinal analysis examined changes in left atrial size from the baseline study, statistically adjusting for age, race, pretreatment left atrial size and LV mass, and serial measurements of systolic blood pressure, body weight, urinary sodium excretion, and physical activity score. Without adjustment for covariates, only hydrochlorothiazide was associated with decreases in left atrial size from baseline at 8 weeks (-1.0 +/- 5.2 mm; P=0.052), 1 year (-2.0 +/- 5.1 mm; P=0.02), and 2 years (4.6+/-7.2 mm; P=0.002). After adjustment for effects of covariates, patients with normal left atrial size had greater reduction (-3.3 mm) in left atrial size at 2 years with hydrochlorothiazide than with any other drug. For patients with left atrial enlargement, left atrial size decreased significantly with hydrochlorothiazide, atenolol, clonidine, and diltiazem at 1 year and with all treatments at 2 years. However, reduction at 2 years was greater with hydrochlorothiazide than with captopril or prazosin.

CONCLUSIONS

Antihypertensive drugs differ in their effects on left atrial size. Hydrochlorothiazide was associated with greater overall reduction of left atrial size than other drugs effective for the treatment of hypertension. Reduction of left atrial size with therapy is in part independent of factors known to influence left atrial size, including LV mass and reduction of LV mass with treatment. The clinical benefit of reducing left atrial size with antihypertensive treatment remains to be determined.

Comparison of effects of antihypertensive drugs on heart rate: changes from baseline by baseline group and over time. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

Baseline heart rate is becoming recognized as a predictor of cardiovascular risk. Various antihypertensive drugs have differing effects on heart rate. A randomized controlled clinical trial of 1292 ambulatory men with stage 1 or 2 hypertension was conducted in 15 Veterans Affairs medical centers. Patients were treated with hydrochlorothiazide, atenolol, captopril, clonidine, diltiazem, prazosin, or placebo for up to 2 years. Heart rates were measured at baseline, the end of titration, 1 year, and 2 years. Data were also stratified by baseline heart rate. A subset of patients had heart rate also determined by electrocardiogram. All drugs except prazosin reduced heart rate from baseline; additional small decreases were obtained over time with hydrochlorothiazide and placebo. The decrease initially achieved with clonidine was attenuated over time. The overall reduction in heart rate was greatest for atenolol (-12.2 beats/min) and least for prazosin (+3.8 beats/min). Only atenolol effected a further reduction of heart rate for patients whose baseline rate was < or =65 beats/min. All drugs reduced heart rate when the baseline was > or =85 beats/min. Data derived by electrocardiogram yielded similar results. The drugs used in this study differ in their ability to reduce heart rate, sustain that reduction over time, and to change heart rate in groups with high or low rates at baseline. The importance of these comparative changes as independent cardiac risk factor variables remains to be determined.

Safety of long-acting dihydropyridine calcium channel blockers in hypertensive patients

Issues raised recently concerning the safety of calcium channel blockers (CCBs) prompted an analysis of the occurrence of cardiovascular events and death in the Pfizer Inc. hypertension clinical trial databases for amlodipine (Norvasc) and nifedipine in the gastrointestinal therapeutic system (GITS) formulation (Procardia XL). Prospectively defined analyses of data from comparative and noncomparative trials of amlodipine and nifedipine GITS were conducted. Outcome measures included cardiovascular and noncardiovascular deaths, and adverse cardiovascular events including new/worsened angina, myocardial infarction (MI), serious arrhythmia, stroke, congestive heart failure, and bleeding. Among all amlodipine-treated patients (n = 32,920), the incidence rates for all-cause death, MI, and new/worsened angina were 3.0, 3.3, and 1.6/1,000 patient-years of exposure, respectively. Among those in comparative trials alone (n = 4,126), the all-cause death rate was 4.1/1,000 patient-years, which was comparable to that of other non-CCB agents and significantly less than that of other CCBs (23.8/1,000 patient-years, p = 0.015), although the difference in rates represents only 2 deaths. Among all nifedipine-GITS-treated patients (n = 2,645), the rate of all-cause death was 4.1/1,000 patient-years, of MI 6.5/1,000 patient-years, and of new/ worsened angina 5.7/1,000 patient-years. The incidence rates for MI and other cardiac events were low in these hypertension trials, and did not differ among treatment groups in either the amlodipine or nifedipine GITS comparative analyses. In the clinical trial databases analyzed, there is no signal suggesting excessive risk of death or cardiovascular events for hypertensive patients treated with amlodipine or nifedipine GITS.

Systolic function in hypertensive men with concentric remodeling

Hypertensive patients with concentric remodeling (relative wall thickness > or = 0.45 and normal left ventricular [LV] mass index) may have poor outcomes. It is unclear whether systolic function abnormalities, shown to be present in some patients with concentric LV hypertrophy (increased LV mass index and relative wall thickness > or = 0.45), are also present in patients with concentric remodeling. To assess LV pump, chamber, and myocardial function in hypertensive men with concentric remodeling, clinical and echocardiographic data of 118 hypertensive men with concentric remodeling were compared with data from 104 hypertensive men with normal relative wall thickness and normal LV mass index. Chamber function was assessed by relating endocardial fractional shortening to end-systolic circumferential stress, myocardial function was assessed by relating midwall fractional shortening to circumferential stress, and pump performance was assessed by stroke volume (Teichholz method). Compared with hypertensive men with normal relative wall thickness, concentric-remodeling patients had lower stroke volume (84 +/- 20 versus 111 +/- 20 mL, P < .001). Endocardial shortening was no different between the two groups (38 +/- 7% versus 40 +/- 7%, P=NS), but midwall shortening was lower in patients with concentric remodeling (20 +/- 3% versus 22 +/- 3%, P < .001), despite lower end-systolic stress (81 +/- 25 versus 117 +/- 37 g/cm2, P < .001). Endocardial and midwall stress-shortening regression plots classified 28% and 42%, respectively, of the concentric remodeling patients below the fifth percentile of hypertensive patients with normal geometry. These data indicate that indexes of chamber and myocardial function are lower than those observed in hypertensive patients with normal geometry. Thus, indices of chamber, myocardial, and pump performance indicate potential abnormalities in systolic function in men with concentric remodeling.

Proteinuria in mild to moderate hypertension: results of the VA cooperative study of six antihypertensive agents and placebo. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

The prevalence and natural history of severe proteinuria in mild to moderate hypertension are not completely defined. We screened 1635 men with a history of hypertension and randomized 1292 with untreated diastolic blood pressure (DBP) 95-109 mmHg to single-drug treatment with either hydrochlorothiazide, atenolol, captopril, clonidine, diltiazem-SR, prazosin, or placebo in a double-blind prospective trial. Twenty-seven of 1635 patients (1.7%) satisfying clinical criteria for primary hypertension were found to have developed proteinuria > 1000 mg/24 hours and were removed from the study. Follow-up data were obtained on 19 of these 27 patients. One patient was found to have focal segmental sclerosis and progressed to end-stage renal disease. Three other patients developed severe (serum creatinine > 3.5 mg/dl) chronic renal failure (one with diabetic nephropathy), one progressed from serum creatinine 1.4 to 2.2 mg/dl, but 14 of the 19 remained with stable serum creatinine < 2.0 mg/dl on follow-up for 6-9 years. Data were available for 1076 of 1155 (93%) treated study patients at end titration, 522/600 (87%) at one year and 322/444 (73%) at two years. There were significant associations for proteinuria with obesity and higher systolic blood pressure. There was a trend toward significant difference in mean 24-hour protein excretion rates at baseline between black (127 mg) and white (139 mg) patients (p = 0.07). There were no statistically significant changes in urinary protein excretion/24 hours between or within the different treatment groups (including placebo). Eighteen patients were removed from the study during the active treatment phase for proteinuria > 1000 mg/24 hours: hydrochlorothiazide 4, placebo 3, diltiazem 3, prazosin 3, atenolol 2, clonidine 2, and captopril 1. We conclude: (1) the prevalence of severe (> 1 g/24 hours) proteinuria in the hypertensive population is significant but does not necessarily imply a poor prognosis; (2) mean 24-hour urinary protein excretion rates did not vary in response to the different classes of antihypertensive drugs; and (3) there was no drug-specific increase in proteinuria detected in this study.

Effect of single-drug therapy on reduction of left ventricular mass in mild to moderate hypertension: comparison of six antihypertensive agents. The Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

BACKGROUND

Antihypertensive drugs may differ in their ability to reduce LV mass. Covariates other than drug selection, such as pretreatment LV mass, body weight, the magnitude of blood pressure reduction, race, and age may modify the response of LV mass to therapy.

METHODS AND RESULTS

Patients with mild to moderate hypertension (diastolic blood pressure, 95 to 109 mm Hg) were randomly allocated to treatment with atenolol, captopril, clonidine, diltiazem, hydrochlorothiazide, or prazosin in a double-masked trial. Patients achieving the goal diastolic blood pressure of <90 mm Hg during drug titration entered a 1-year maintenance period. Longitudinal analysis examined changes from baseline echocardiogram in LV mass at 8 weeks and at 1 year, statistically adjusted for pretreatment LV mass, systolic blood pressure, body weight, sodium excretion, physical activity, race, and age. Significant reductions at 1 year in adjusted LV mass were seen for patients in the highest tertile of pretreatment LV mass treated with hydrochlorothiazide (mean, -42.9; 95% confidence limits, -65.5, -20.2 g), captopril (mean, -38.7; 95% confidence limits, -61.0, -16.4 g), and atenolol (mean, -28.1; 95% confidence limits, -50.9, -5.3 g). These treatment effects differed from those of prazosin, diltiazem, or clonidine.

CONCLUSIONS

Antihypertensive drugs have disparate effects on LV mass independent of the magnitude of blood pressure reduction. Patients with adequate blood pressure control on captopril, hydrochlorothiazide, and atenolol show a reduction of LV mass after 1 year of treatment, whereas patients on diltiazem, clonidine, or prazosin do not.

Acetaminophen-related acute renal failure without fulminant liver failure

BACKGROUND

Our patient experienced acute renal failure but not fulminant hepatic failure from acetaminophen toxicity.

OBJECTIVE

To review the clinical and laboratory characteristics of similar cases of acetaminophen nephrotoxicity.

METHODS

A MEDLINE search and medical record search at two large teaching hospitals.

RESULTS

We reviewed our index case, a patient at Jackson Memorial Hospital, and 34 additional patients with acetaminophen nephrotoxicity reported in the literature. Oliguria was present in 23 of 31 patients. There was no difference in peak serum creatinine levels between patients treated with N-acetylcysteine and those not treated. The onset of acute renal failure was from 2-5 days after overdose, and peak serum creatinine levels occurred 3-16 days (average 7.3 days) after overdose. Thirteen patients required hemodialysis; all but one were oliguric. Renal failure was spontaneously reversible in all patients.

CONCLUSION

Although uncommon, it is possible to have acute renal failure due to acetaminophen toxicity in the absence of fulminant hepatic failure.

Left atrial size in hypertensive men: influence of obesity, race and age. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

OBJECTIVES

We sought to determine the relations of left atrial (LA) size to blood pressure, obesity, race, age and left ventricular (LV) mass in hypertension.

BACKGROUND

Although obesity, race and age may influence LV mass, their effects on LA size have not been defined in hypertension.

METHODS

Left atrial size was measured in 690 men (58% African-Americans) with mild to moderate hypertension (mean [+/-SD] blood pressure 152 +/- 15/98 +/- 6 mm Hg) and a high prevalence of LV hypertrophy. Effects of LV mass, adiposity, race, age, physical activity, height, weight, sodium excretion, plasma renin activity and heart rate were examined.

RESULTS

Left atrial size was greater (p < or = 0.0001) in obese (44.2 +/- 5.7 mm) than in overweight (41.6 +/- 5.9 mm) or normal weight (38.9 +/- 6.2 mm) patients. Left atrial enlargement (> or = 43 mm) was present in 56% of obese patients compared with 42% of overweight and 25% of normal weight hypertensive men. As age increased, white patients had a greater LA size than African-American patients. Although there was no relation between LV mass and LA size in normal weight patients, there was a significant positive relation in obese patients. On multiple regression analysis, obesity was the strongest independent predictor of increased LA size.

CONCLUSIONS

Obesity is the strongest predictor of LA size in patients with hypertension and amplifies the relation between LA size and LV mass. Race influences effects of age and hypertension on LA size. Because increased LA size and LV mass (also influenced by obesity) are associated with an adverse outcome, these findings underscore the importance of obesity, race and age with regard to the cardiac effects of hypertension.

Prevention of diabetic nephropathy

Normalization of blood pressure--and use of an ACE inhibitor or AT1-receptor blocker for patients with abnormal albumin or creatinine levels--can prevent or significantly slow the rate of progression toward end-stage renal disease.

Lessons from combination therapy in Veterans Affairs Studies. Department of Veterans Affairs Cooperative Study Group on antihypertensive agents

A subset of 102 patients of an original cohort of 1292 with stage 1 to 2 hypertension was characterized by having failed to achieve goal blood pressure (< 90 mm Hg diastolic) after treatment with two single antihypertensive drugs. These patients were given a combination of the two drugs on which they had failed to achieve blood pressure goal when they were administered as single-drug therapy. The drugs were hydrochlorothiazide, atenolol, captopril, diltiazem-SR, clonidine, and prazosin. We examined the responses in each of the drug combination categories by the order that the drugs were administered, by estimated total response rates for the combinations, and by age and race. The order of drug administration did have an effect for some of the drug pairs. This was of two types: 1) different results for each member of the pair, but the same combination result; and 2) different end result of the combination. An example of the first type is that prazosin had only a 6% response rate in patients who had failed on diltiazem, while diltiazem had a 22% response rate in patients who had failed on prazosin. Nevertheless, the combinations yielded the same total responses (86% and 84%) regardless of order. An example of the second type is that captopril-diltiazem was less effective in total response than diltiazem-captopril (88% v 97%). Differences were seen in the response to combinations in the race and age groups. There were ordering differences of type similar to those described above. We conclude that combination drug therapy is highly effective even when the individual components have failed and that some differences in response by order of drug administration may occur.

Comparison of plasma lipid and lipoprotein profiles in hypertensive black versus white men. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

An abnormal plasma lipid and lipoprotein profile is an independent and strong predictor of mortality and morbidity from coronary artery disease (CAD). We report on plasma lipid and lipoprotein profiles with respect to race, age, obesity, blood pressure (BP), smoking, and drinking history in 1,292 male veterans with a diastolic BP of 95 to 109 mm Hg while off antihypertensive medications. Blacks had 24% (p <0.001) lower triglycerides than whites. In contrast, the following parameters were higher in blacks than in whites by the indicated percentages: high-density lipoprotein (HDL) cholesterol, 16% (p <0.001); HDL2 cholesterol, 36% (p <0.001); apolipoprotein (Apo) A1, 8% (p <0.001); HDL/low-density lipoprotein (LDL), 18% (p = 0.018); HDL2/LDL, 36% (p = 0.031); HDL2/HDL3, 21% (p <0.001); and Apo A1/Apo B, 15% (p <0.001). Triglycerides were unchanged up to age 60, but were lower by 24% (p <0.001) in those aged > or = 70. Apo A1 levels were higher (p <0.001), whereas LDL cholesterol was lower (p <0.008) in moderate alcohol consumers versus abstainers. Triglycerides were higher (p <0.001), whereas HDL, HDL2 cholesterol, and Apo A1 were lower (p <0.001) with increasing obesity. Moderate alcohol consumption had a strong favorable effect on HDL, HDL2, and HDL3 cholesterol among subjects of normal weight, but this effect was diminished in obese subjects. Total and LDL cholesterol were higher by 6.4% (p = 0.001) and 9.4% (p <0.003), respectively, whereas HDL cholesterol remained unchanged in those with diastolic BP of 105 to 109 mm Hg versus those with diastolic BP of 95 to 99 mm Hg. We conclude that hypertensive black men have lipid and lipoprotein profiles indicative of less CAD risk than white men. Chronic moderate alcohol consumption correlates with a favorable plasma lipid and lipoprotein profile in normal, but not obese, men. Obesity is associated with an adverse plasma lipid and lipoprotein profile. Thus, race, alcohol intake, and obesity may be important modifiers of CAD in untreated hypertensive men.

Hypertension in Haitians: results of a pilot survey of a public teaching hospital multispecialty clinic

Little is known about hypertension in Haitians. We performed a pilot survey of ambulatory Haitian patients in a multispecialty clinic at a large public teaching hospital. Approximately 10% of the clinic population was of Haitian origin. Clinical data were collected on 88 consecutive Haitian patients. Of these 88, 77 (87.5%) were hypertensive (SBP > or = 140 or DBP > or = 90 mm Hg or taking antihypertensive medication). The characteristics of the hypertensive patients were: age 54.1 +/- 13.0 (s.d.) years; 27 men, 50 women; 12/64 (19%) smoked; 7/63 (11%) used alcohol. Diabetes was present in 21/77 (27%). In patients for whom height and weight were available, obesity was present in 52%. Using JNC V criteria, 18 (23%) had Stage 1, 16 (21%) Stage 2, 18 (23%) Stage 3, and 25 (33%) Stage 4 hypertension. Despite 63/77 (82%) being treated for hypertension, only 20 (26%) were controlled (< 140/< 90 mm Hg). Of those under treatment, 29 were taking one drug; 18 (two drugs); 12 (three drugs); and four (four drugs). Target organ damage was evident in 37 (48%), including coronary artery disease (8), CHF (6), chronic renal failure (15), stroke (9), and LVH by ECG (19). There was evidence of severe noncompliance in 32 (42%). We conclude that in this clinic sample, hypertension was highly prevalent and unusually severe in terms of blood pressure (BP) level, refractoriness to treatment, and target organ consequences. Further studies are indicated.

Lessons on the interaction of race and antihypertensive drugs from the VA cooperative study group on antihypertensive agents

The Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents, organized by Dr. Edward D. Freis, has made numerous contributions to our knowledge about hypertension and its treatment. In the late 1970s the group observed post hoc that there were racial differences in response to hydrochlorothiazide and propranolol. Subsequent studies were designed to seek out racial differences if they existed. A series of observations led to the design of a comparative study of six drugs and placebo used as single-drug therapy of mild to moderate hypertension in men. Further analyses of those data have indicated that racial differences still exist when a second drug is substituted for a failed first drug. A combination of two drugs that had previously failed to achieve control of blood pressure did produce control in 58% of the patients. Electrocardiographic data suggested that black patients were much more likely to have left ventricular hypertropy (LVH) than whites, but analysis of echocardiograms showed that there was no racial difference in the prevalence of LVH. Additional analyses are in progress addressed to serum lipid changes, proteinuria, and drug-induced changes in left ventricular mass.

Results of combination anti-hypertensive therapy after failure of each of the components. Department of Veterans Affairs Cooperative Study Group on Anti-hypertensive Agents

We randomised ambulatory men with diastolic blood pressure (BP) 95-109 mmHg without anti-hypertensive medication to single drug treatment with either hydrochlorothiazide 12.5-50 mg/day, atenolol 25-100 mg/day, captopril 25-100 mg/day, clonidine 0.2-0.6 mg/day, diltiazem-SR 120-360 mg/day, prazosin 4-20 mg/day or placebo in a double-blind prospective trial. The assigned drug was titrated to a goal BP of < 90 mm Hg. Patients not achieving goal BP were rerandomised to an alternative single active drug. Non-responders to the second drug received the first drug in combination with the second. Of the 102 non-responders to both drugs who qualified for the combination, 59 (57.8%) responded. The combination pairs that included a diuretic achieved diastolic goal BP in 69% and < 140 mm Hg systolic in 77% compared with 51% and 46%, respectively, for those combinations without a diuretic (P = 0.067; P = 0.002). Six of the eight terminations due to adverse drug reactions were in combinations containing prazosin; three of these six were hypotensive reactions. We conclude that two single drugs of insufficient efficacy to control BP individually have a high probability of achieving goal BP when combined, especially if the combination contains a diuretic.

Response to a second single antihypertensive agent used as monotherapy for hypertension after failure of the initial drug. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

BACKGROUND

An important issue in clinical practice is how to treat patients whose blood pressure does not respond to the first antihypertensive drug selected.

OBJECTIVE

To analyze the antihypertensive response of patients who had failed to achieve their diastolic blood pressure goal (< 90 mm Hg at the end of 8 to 12 weeks of titration) with one of six randomly allocated drugs or placebo to the random allocation of an alternate drug.

METHODS

We initially randomized 1292 men with diastolic blood pressure of 95 to 109 mm Hg to treatment with hydrochlorothiazide, atenolol, captopril, clonidine hydrochloride, diltiazem hydrochloride (sustained release), prazosin hydrochloride, or placebo. Of 410 men in whom initial treatment failed, 352 qualified for randomization to the alternate drug.

RESULTS

Of the 352 patients, 173 (49.1%) achieved their goal diastolic blood pressure, in 133 (37.8%) the alternate drug failed, and 46 (13.1%) left the study for various reasons. Overall response rates were as follows: diltiazem, 63%; clonidine, 59%; prazosin, 47%; hydrochlorothiazide, 46%; atenolol, 41%; and captopril, 37%. The best response rate for patients in whom hydrochlorothiazide failed was achieved with diltiazem (70%); after atenolol failure, clonidine (86%); after captopril failure, prazosin (54%); after clonidine failure, diltiazem (100%); after diltiazem failure, captopril (67%); and after prazosin failure, clonidine (53%). The combined response rate for patients initially randomized to an active treatment was 76.0%, which is similar to that achieved by the combination of two drugs in previous studies.

CONCLUSIONS

We conclude that sequential single-drug therapy is a rational approach for treatment of hypertension in patients in whom initial drug therapy has failed.

Calcium channel blockers. Is it time to split the lump?

Antihypertensive drug classes such as thiazide diuretics, angiotensin-converting enzyme inhibitors, beta-adrenergic blocking agents, peripheral alpha 1-antagonists, and central alpha 2-agonists all describe therapeutic agents that are quite similar to each other and strikingly different from members of the other classes. A glaring exception is the rubric "calcium channel blocker," under which strikingly dissimilar drugs have been lumped. Although the phenylalkylamines (verapamil and gallapamil) and benzothiazepines (diltiazem and TA3090) bind at different receptors on the alpha 1 component of the calcium channel, they are reasonably similar in their clinical pharmacology. For example, both types of drugs slow the heart rate and there are intravenous preparations that are used to treat supraventricular tachycardia. The dihydropyridines (nifedipine and many others) bind to another receptor on the alpha 1 component, but have markedly different pharmacologic properties. For example, they tend to increase the heart rate, do not cause constipation, but are more likely to cause peripheral edema. I propose that we refer to this entire class of drugs as "calcium antagonists," that we continue to refer to verapamil, diltiazem, and similar drugs as "calcium channel blockers," but recognize the very different properties of nifedipine and like drugs by referring to them as dihydropyridines or DHPs.

Department of veterans Affairs single-drug therapy of hypertension study. Revised figures and new data. Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

The antihypertensive efficacy of six drugs and placebo was compared in 1292 men with untreated diastolic blood pressure of 95 to 109 mm Hg. The primary end point "success" was defined as the patient having achieved a diastolic blood pressure of < 90 mm Hg at the end of the drug titration period and having maintained a diastolic blood pressure of < 95 mm Hg for 1 year without drug intolerance. The original published success rate data (N Engl J Med 1993;328:914-921) were discovered to be in error due to a computer programming code omission (N Engl J Med 1994;330:1689). This paper presents corrected graphic figures. The corrected success rates were generally higher than originally published. Overall, diltiazem (72%) was significantly higher than hydrochlorothiazide (55%), prazosin (54%), captopril (50%), and placebo (31%); clonidine (62%) and atenolol (60%) were intermediate. There were some changes in the hierarchy of drug response, but important differences in success rates according to age by race subgroups remained. Whites responded well to all drug classes, except for lower efficacy of hydrochlorothiazide in younger whites. Blacks responded better to diltiazem than other agents. In addition, we have analyzed the data using a definition of success based on < 90 mm Hg for 1 year. Use of the <90 mm Hg criterion reduced the rate of success, but had only a minor effect on the drug success rate hierarchy. We conclude that single-drug antihypertensive therapy is effective in a majority of stage 1 to 2 diastolic hypertensive patients, although there are important age-by-race differences in success rates among various drug classes.

Importance of obesity, race and age to the cardiac structural and functional effects of hypertension. The Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

OBJECTIVES

The purpose of this study was to determine the effects of obesity and its interaction with age, race and the magnitude of blood pressure elevation in a large cohort of patients with mild to moderate hypertension and a high prevalence of left ventricular hypertrophy.

BACKGROUND

Obesity, race and age each have important effects on the incidence and severity of hypertension and may contribute to the effects of blood pressure elevation on the cardiac manifestations of hypertension.

METHODS

Left ventricular structure and function were assessed with two-dimensional targeted M-mode echocardiography in 692 men with mild to moderate hypertension (average blood pressure 153/100 mm Hg), and the data were compared in relation to obesity (determined from body mass index), age, race, blood pressure, physical activity, plasma renin activity, urinary sodium excretion, hematocrit, heart rate and serum lipids.

RESULTS

Left ventricular hypertrophy was common (63% with increased left ventricular mass, 22% with left ventricular hypertrophy on the electrocardiogram [ECG]). On multivariable regression analysis, body mass index was the strongest predictor of left ventricular mass and magnified the slope relation of blood pressure to left ventricular mass. Despite a greater prevalence of ECG left ventricular hypertrophy in blacks (31%) than in whites (10%), left ventricular mass and echocardiographic prevalence of left ventricular hypertrophy did not differ by race. However, septal, posterior left ventricular and relative wall thickness were greater in black than in white men.

CONCLUSIONS

Obesity is the strongest clinical predictor of left ventricular mass and left ventricular hypertrophy in men, even in those with mild to moderate hypertension of sufficient severity to be associated with a high prevalence of left ventricular hypertrophy. Moreover, independent effects of systolic blood pressure on left ventricular mass are amplified by obesity. Although race does not affect left ventricular mass or the prevalence of left ventricular hypertrophy, black race is associated with greater relative wall thickness, itself a predictor of unfavorable cardiovascular outcome.

Modern strategies to prevent coronary sequelae and stroke in hypertensive patients differ from the JNC V Consensus Guidelines

In recent years, government agencies of many countries have established consensus guidelines for the evaluation and treatment of hypertension. Once published, guidelines tend to be perceived as directives by a variety of health care providers. Unfortunately, these guidelines often do not reflect the practices of most hypertension experts. This report summarizes the opinions of seven hypertension experts concerning the impact of "official" guidelines on clinical practice. In addition, the individual therapeutic recommendations of these panel members are summarized. Their different treatment strategies reflect the diversity of first rate treatment plans that aim to reduce the cardiovascular sequelae in individual patients with essential hypertension. Most importantly, not one of these seven treatment strategies followed the "preferred" treatment of the U.S. guidelines, which recommend diuretics and beta-blockers as first-line therapy. The present authors approach the treatment of hypertension as a means to reduce cardiovascular events. Thus, reduction of blood pressure is not the most important therapeutic endpoint. The panel believes that whereas many different drugs can produce effective blood pressure reduction, the modern primary goal of antihypertensive drug therapy is to select a regimen most likely to prolong the quality and duration of life. In real terms, this means that the primary goal of treatment is the prevention of the major vascular sequelae of hypertension (heart attack, ventricular remodeling, hypertrophy, heart failure, and stroke) that shorten useful life. There are a number of effective hypertensive treatments, which can be selected based on individual patient requirements. However, many consensus guidelines do not allow the flexibility required to optimize individual patient treatment. As a result, health care providers should not feel compelled to regard the preferences of "official" guidelines as the best, modern, state-of-the-art therapy for an individual patient. All seven experts who are deeply involved in the daily care of patients preferred drugs other than beta-blockers and diuretics (the Joint National Committee [JNC] choices) for first-line therapy of hypertension.

Angiotensin-converting enzyme inhibitors in hypertension. A dozen years of experience

Introduction of the first angiotensin-converting enzyme (ACE) inhibitor, captopril, in 1981 marked a major advance in the treatment of essential hypertension. This article reviews the 12 years of clinical experience during which it and other ACE inhibitors have become recognized as first-line agents for treating hypertension. The benefits of ACE inhibition in diabetic patients are being defined. In recent years, beneficial effects on glucose handling, left-ventricular mass, quality of life, renal function, and myocardial protection have become recognized. For these reasons, and because of their excellent safety profile, ACE inhibitors are now widely used for the treatment of hypertensive patients.

Alterations in heart rate variability and its circadian rhythm in hypertensive patients with left ventricular hypertrophy free of coronary artery disease

Heart rate variability (HRV) and its circadian rhythm were evaluated in 22 patients with treated hypertension and left ventricular hypertrophy in whom coronary artery disease was excluded by stress thallium or angiography. By using 24-hour Holter monitoring, HRV and its spectral components were measured. Findings were compared with 11 age-matched normal controls. The difference between mean R-R intervals during sleep (11 PM to 7 AM) and while awake (9 AM to 9 PM) (73 +/- 33 vs 263 +/- 63 msec, p < 0.0001) and the mean 24-hour SD of the R-R intervals (55 +/- 6.3 vs 93 +/- 11, p < 0.0001) were lower among the hypertensive patients compared with controls. The percentage of difference between successive R-R intervals that exceeded 50 msec, a measure of parasympathetic tone, was also lower among the hypertensive patients (6.8 +/- 7.1 vs 13.6 +/- 8.9, p < 0.002); it increased at night and decreased during the day among the controls, and this circadian rhythm was blunted among the patients. Spectral analysis showed that power in the high-frequency range (0.15 to 0.40 Hz) was lower among the hypertensive patients during 21 of 24 hours but that the difference was statistically significant only during 9 hours (p ranging from < 0.05 to 0.009). Power in the low-frequency range (0.04 to 015 Hz) was lower at night, increased in the morning, and higher during the day among controls; this circadian rhythm was absent among hypertensive patients.(ABSTRACT TRUNCATED AT 250 WORDS)

[The cost of quality assurance]

This paper views quality assurance costs as appraisal costs. We used cost accounting techniques to estimate the cost of quality assurance activities in a large university affiliated Veteran Administration Medical Center. In addition to the personnel employed full-time for quality assurance activities, all other employees in or directly in support of clinical services were interviewed in order to determine the per cent of their work time devoted to specific quality assurance activities. The per cent time committed was multiplied by the salary and benefits package for each employee and the total computed for the facility. In addition, non-salary overhead expenses were estimated by multiplying the salary and fringe benefit costs to the ratio of total medical center non-personnel costs to total medical center costs. We found that 3.39 per cent of the total budget or $4,884,775 was devoted to quality assurance activities. The highest costs aside from the designated quality assurance personnel were for pharmacy, Laboratory, extended care (including nursing home), psychiatry, and nursing services. We did not attempt a formal benefit analysis. We concluded that quality assurance activities in a major medical center are not free. Careful cost accounting studies should be performed both to determine the cost of quality assurance and to identify its specific benefits.

Single-drug therapy for hypertension in men. A comparison of six antihypertensive agents with placebo. The Department of Veterans Affairs Cooperative Study Group on Antihypertensive Agents

BACKGROUND

Characteristics such as age and race are often cited as determinants of the response of blood pressure to specific antihypertensive agents, but this clinically important issue has not been examined in sufficiently large trials, involving all standard treatments, to determine the effect of such factors.

METHODS

In a randomized, double-blind study at 15 clinics, we assigned 1292 men with diastolic blood pressures of 95 to 109 mm Hg, after a placebo washout period, to receive placebo or one of six drugs: hydrochlorothiazide (12.5 to 50 mg per day), atenolol (25 to 100 mg per day), captopril (25 to 100 mg per day), clonidine (0.2 to 0.6 mg per day), a sustained-release preparation of diltiazem (120 to 360 mg per day), or prazosin (4 to 20 mg per day). The drug doses were titrated to a goal of less than 90 mm Hg for maximal diastolic pressure, and the patients continued to receive therapy for at least one year.

RESULTS

The mean (+/- SD) age of the randomized patients was 59 +/- 10 years, and 48 percent were black. The average blood pressure at base line was 152 +/- 14/99 +/- 3 mm Hg. Diltiazem therapy had the highest rate of success: 59 percent of the treated patients had reached the blood-pressure goal at the end of the titration phase and had a diastolic blood pressure of less than 95 mm Hg at one year. Atenolol was successful by this definition in 51 percent of the patients, clonidine in 50 percent, hydrochlorothiazide in 46 percent, captopril in 42 percent, and prazosin in 42 percent; all these agents were superior to placebo (success rate, 25 percent). Diltiazem ranked first for younger blacks (< 60 years) and older blacks (> or = 60 years), among whom the success rate was 64 percent, captopril for younger whites (success rate, 55 percent), and atenolol for older whites (68 percent). Drug intolerance was more frequent with clonidine (14 percent) and prazosin (12 percent) than with the other drugs.

CONCLUSIONS

Among men, race and age have an important effect on the response to single-drug therapy for hypertension. In addition to cost and quality of life, these factors should be considered in the initial choice of a drug.

Antihypertensive drug therapy does not perturb the circadian blood pressure pattern

The literature was reviewed to determine whether failure of older antihypertensive drugs to suppress the early morning increase of blood pressure was responsible, in part, for the less than satisfactory rate of reduction in cardiovascular mortality rates in the United States. The authors found that neither the old nor the new antihypertensive drugs altered the 24-hour blood pressure curve pattern, although long-acting drugs did show continued effect at the end of the 24-hour period when compared with placebo. The efficacy of these drugs most likely lies with their blood pressure lowering and other ancillary effects and not with pattern changes. More importantly, examination of new data (1989) shows that the rate of decline in death due to diseases of the heart has exceeded that for cerebrovascular diseases. Our overall health care effort may be more successful than we thought.

Adverse effects of angiotensin-converting enzyme inhibitors in antihypertensive therapy with focus on quinapril

Angiotensin-converting enzyme (ACE) inhibitors are useful first-line drugs in the therapy of mild and moderate hypertension. Adverse reactions to this drug class are rarely serious. Hypotension, cough, rash, and taste disturbance are uncommon; reduced glomerular filtration and hyperkalemia occur infrequently; angioedema is rare and neutropenia is extremely rare. Quinapril is a new ACE inhibitor that is converted to biologically active quinaprilat in the liver. This ACE inhibitor has a rapid onset of action and inhibits local tissue converting enzyme systems in kidney, heart, and brain, as well as in the circulating renin-angiotensin system. Clinically significant adverse effects of quinapril occur at low rates. In 1,771 patients receiving quinapril, the reported incidence of the first occurrence of orthostatic hypotension was comparable to that seen in patients receiving placebo. In other studies, headache was reported by up to 4.7% of patients receiving quinapril, which is comparable to reported incidences of headache in patients receiving other ACE inhibitors. Other adverse events reported at rates greater than 1% include cough with associated rhinitis and bronchitis, dizziness, and somnolence. Such adverse events have only rarely led to the withdrawal of patients from clinical studies of quinapril.