A Pharmacotherapy of Hypertension

The Seventh Report of the Joint National Committee on the Detection, Evaluation, and Treatment of High Blood Pressure (JNC7) is the national clinical guideline that was developed to aid clinicians in the management of hypertension. This chapter reviews relevant components of this evidence-based guideline with a focus on the pharmacotherapy of hypertension. Data from the National... 

FIGURE 59-1. Pharmacotherapy treatment algorithm. A select population of individuals, based on body mass index (BMI) and waist circumference (WC) together with concurrent risk factors, may benefit from medication therapy as an adjunct to a program of weight loss that includes diet, exercise, and behavioral modification. (CHD, coronary heart disease DM, diabetes mellitus, HTN, hypertension INC WC, >40 inches for males and >35 inches for females LCD, low-calorie diet.)... 

Herbs have been used as medical treatments since the beginning of civilization and some herbal derivatives (e.g., aspirin, reserpine, and digitalis) have become a mainstay of human pharmacotherapy. For cardiovascular diseases, herbal treatments have been used in patients with congestive heart failure, systolic hypertension, angina pectoris, atherosclerosis, cerebral insufficiency, venous insufficiency, and arrhythmia. Scientific validation of several plant species has proved the efficacy of the botanicals in reducing the... 

Carter BL, Barnette DJ, Chrischilles E, Mazzotti GJ, Asali ZJ. Evaluation of hypertensive patients after care provided by community pharmacists in a rural setting. Pharmacotherapy 1997 17 1274-1285. 

Although not a quantitative measure of renal function, urinary microalbuminuria has been identified as an early marker of renal disease in patients with diabetic nephropathy and numerous other conditions, such as hypertension and obesity. Patients with microalbuminuria (30 to 300 mg/day) on at least two occasions or overt albuminuria (>300 mg/day) should begin to receive pharmacotherapy. For children, microalbuminuria is considered present if albumin excretion exceeds 0.36 mg/kg per day, and overt albuminuria has been defined as an excretion rate that exceeds 4 mg/kg per day. The urinary albumin creatinine ratio is also an accurate predictor of 24-hour proteinuria, a marker of renal disease. Guidelines for monitoring indicate that a urine albumin creatinine ratio of >30 mg/g places the patient at increased risk of developing diabetic nephropathy and is an indication for the initiation of pharmacotherapeutic intervention. Microalbuminuria has also been suggested as a risk factor for renal dysfunction among patients with essential hypertension. ... 

Consequently, diuretics have a variety of uses. Thiazide diuretics may be used either alone or in combination with other pharmacotherapy for the treatment of hypertension. Loop diuretics can provide immediate diuresis and are used for heart failure and in lieu of thiazides in patients with compromised renal function. In addition to more traditional uses, certain potassium-sparing diuretics provide added benefit to other pharmacotherapy in patients with primary hyperaldosteronism, heart failure, or post-acute myocardial infarction. Carbonic anhydrase inhibitors have limited use for diuresis however, they may be used to reduce intraocular pressure and treat acute mountain sickness. 

FIGURE 19-2. Relationship of sinusoids to hepatocytes and the venous system. (From Timm EJ, Stragand JJ. Portal hypertension and cirrhosis. In DiPiro JT, Talbert RL, Yee GC, et al, (eds.) Pharmacotherapy A Pathophysiologic Approach. 6th ed. New York McGraw-Hill 2005 695, with permission.)... 

Evidence-based pharmacotherapy provides a succinct appreciation of the benefits of a drug, but rarely takes into account the patient s quality of life. Eor instance, intensive statin therapy is recommended because it reduces the incidence of cardiovascular death (odds ratio 0.86), myocardial infarction (odds ratio 0.84), and stroke (odds ratio 0.82) however, the increased risks for any adverse event (odds ratio 1.44), for abnormalities on liver function testing (odds ratio 4.48), for elevations in CK (odds ratio 9.97) and for adverse events requiring discontinuation of therapy (odds ratio 1.28) are less often taken into account by the prescriber. This example emphasises that individualisation is of the utmost importance to keep an acceptable benefit/risk ratio (Clin Ther 2007 29 253-60). The benefits of evidence-based pharmacotherapy may be obtained whenever concordance/compliance of the patient is adequate. However, concordance rate is slightly higher than 30% for chronic conditions, such as hypertension (Curr Hypertens Rep 2007 9 184-9), indicating that the patient has to be educated about the use of drugs, and therapy has to be individualised. 

Developmental differences, disease presentation, disease progression, and comorbidities also need to be considered when determining pediatric pharmacotherapy. Even when the mechanism of action and PD response surface may be similar between pediatric and adult populations, differences in therapy may be indicated based on disease progression. For example, hypertension rarely presents as primary finding in children but most frequently as secondary to renal disease or other processes, which frequently impact the pharmacologic goals of therapy. HIV infection and AIDS will result in a 50% 2-year mortality in untreated infants yet typically takes 10 years in adults to wear down the immune system to the point at which opportunistic infections and AIDS take hold. Thus, therapeutic targets must account for these differences especially if these therapies will be used for chronic conditions. 

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