Antihypertensive drugs: how different classes can impact patients' coronary heart disease risk profile and quality of life

Back to thiazide-diuretics for hypertension: reflections after a decade of irrational prescribing

BACKGROUND

Whether newer antihypertensive drugs, such as calcium channel blockers, angiotensin converting enzyme inhibitors and alpha blockers are more effective than thiazides and beta blockers in preventing coronary disease, has been debated for years.

DISCUSSION

Recently several trials addressing this issue have been finalised, and they provide a convincing answer: the newer drugs are no better than the older ones. In the largest trial to date (ALLHAT), thiazide-type diuretic was found to offer advantages over newer drugs. The medical community should now be capable of reaching consensus, and recommend thiazides as the first line therapy for the treatment of hypertension. Prescribing physicians, cardiologists, drug companies and health authorities are all partly responsible for the years of irrational prescribing that we have witnessed.

SUMMARY

All stakeholders should now contribute in order to achieve what is clearly in the public's interest: implementing the use of thiazides in clinical practice.

Effect of perceived barriers on compliance with antihypertensive medication

Noncompliance with antihypertensive medication remains an obstacle to the management of hypertension, and despite research efforts over the past decade, the predictors of noncompliance remain unclear. According to values expectancy theory, individuals rationally choose noncompliance when the barriers or costs of treatment outweigh the expected benefits. Noncompliance, therefore, is likely to occur when net costs of treatment are high. Using a cross-sectional study design among subjects (n = 197) attending a specialized clinic for hypertension, we measured "net barriers" (costs), self-reported compliance, and possible determinants of noncompliance, including socio-demographics, the medical regimen, and locus of control. The effect of each quartile of the net barriers score (none, low, moderate, and high) on compliance, controlling for potential effect modifiers, was assessed using logistic regression modeling. Noncompliance (47%) was associated with younger age, higher salt use, longer duration of treatment, and higher levels of net barriers, but duration of treatment modified the effect of net barriers. Among subjects in short-term treatment, noncompliance increased with severity of net barriers suggesting a dose-response effect. In contrast, patients in long-term treatment showed no dose-response effect but a consistent association between noncompliance and levels of net barriers. Subjects at greater risk for noncompliance, however, were those who reported high net barriers, regardless of duration of treatment. Net barriers accounted for 50% of the noncompliance and appeared most important for patients who were younger or in the early stages of treatment. Implications for health care providers are discussed.

Effects of antihypertensive therapy on blood pressure control, cognition, and reactivity. A placebo-controlled comparison of prazosin, propranolol, and hydrochlorothiazide

A randomized, placebo-controlled trial was conducted to compare the effects of treatment with prazosin, propranolol, or hydrochlorothiazide on the following variables: blood pressure, cognitive and psychomotor skills, cardiovascular reactivity to natural and laboratory challenges, and serum lipid and lipoprotein levels. Side effects were recorded and patients evaluated how they felt during their treatment. Sixty-nine men, 35 percent black, aged 25 to 55 (mean 51.3) years, with diastolic blood pressures between 90 and 104 mm Hg (mean, 93.3 mm Hg), completed the study. There were no differences between active treatment groups in the proportion of patients with controlled blood pressure during the maintenance phase of the study. In the cognitive and psychomotor tests, the hydrochlorothiazide group showed significantly less improvement from baseline than the other treatment groups on the block design subscale of the Wechsler Adult Intelligence Scale-Revised, and there was a trend for the propranolol group to have less improvement from baseline than the other groups on the digit span subscale. There were no other significant pretreatment to post-treatment changes in the other cognitive or psychomotor tests, the Russell Revision of the Wechsler Memory Scale, or a number of computerized reaction-time and signal-detection tasks. In the reactivity testing, there was a significantly lower increase in heart rate in the prazosin group compared with placebo during the second laboratory challenge of the Stroop Color Interference Test. Post-treatment declines in ambulatory blood pressure were seen in all of the drug treatment groups in average and maximal diastolic and systolic blood pressures. Both propranolol and hydrochlorothiazide treatment resulted in low-density lipoprotein cholesterol levels that were higher than baseline and the hydrochlorothiazide treatment had significantly increased total cholesterol levels. In contrast, the prazosin-treated group experienced no adverse changes in these parameters. Overall, the propranolol group had significantly more moderate and severe side effects than did the other three groups. Considering the pattern of blood pressure control, cognitive and psychomotor effects, changes in lipid levels, and magnitude of side effects, prazosin seems to have the most advantageous profile in this study of the three anti-hypertensive agents evaluated.

Quality of life issues in hypertension: consequences of diagnosis and considerations in management

Most patients with mild to moderate hypertension are asymptomatic. Any adverse response to nonpharmacologic or pharmacologic therapies can negatively influence some aspect of the patient's sense of well-being and life satisfaction; this will likely limit the compliance with and the resultant benefits of therapy. The diagnosis of hypertension itself is associated with psychological consequences, termed the "labeling effect," that impair life quality. A number of life-style modifications and a variety of highly effective and safe classes of antihypertensive agents can satisfactorily control blood pressure in most patients. Evaluation of the patient's response to an antihypertensive regimen should, in addition to measurement of the level of blood pressure and review of laboratory test values, include assessment of quality of life outcomes: impact of therapy on the patient's daily routine, fatigue or activity limitation, sexual dysfunction, impairment of memory, alertness, mood, or cognitive ability, sleep dysfunction, work performance and satisfaction, and satisfaction with family, social, and leisure time activities.