CHAP TER 7 Methods of Tertiary Prevention Table 17-2 Evaluation of Blood Pressure(BP)and Staging of Hypertension, Based on Average Systolic BP and Diastolic BP in Persons Not Acutely Ill and Not Taking Antihypertensive Medications' Systolic BP(mm Hg) Diastolic BP(mm Hg) nterpretation Initiate Drug Treatment? Normal BP 20-139 8C-89 Prehypertension some cases 140-159 Stage I hypertension Yes: thiazides for most tage 2 hypertension hypertension. Not 一标 alifies is taken as the stage of hypertension. For example, if systolic is 165 and diastolic 95 mm Hg, this is stage monitored at 2-year intervals. Individuals with prehyper- and vasodilators. Although many antihypertensive medica- ension should be counseled about lifestyle changes and tions cause significant side effects, the wide range of choices should be used to develop a treatment plan that is satisfac tension should begin diet and lifestyle changes and should tory to the patient. diet and lifestyle changes and should be trea. should begin In controlled clinical trials, thiazide-type diuretics have other drugs. Thiazide diuretics should be used with caution cian should check for any evidence of target organ damage, in elderly patients because of possible orthostatic hypoten ecause any stage of hypertension is more severe if there is sion(lightheadedness or fainting), acute renal failure, and evidence of such damage electrolyte imbalances (particularly low potassium). Beta Most hypertension is classified as essential hypertension, blockers are a good choice for patients who have CAD, heart aning that the specific underlying cause is unknown. failure, or diabetes. Beta blockers are contraindicated Depending on the patient, however, hardening of the arter- however, in patients with conduction abnormalities, and car s,fluid retention, or changes in the renin-angiotensin- dioselective beta blockers are often used in patients with aldosterone system may be involved. Nonessential asthma or COPD. Beta blockers seem to be less effective as secondary)hypertension is caused by other, often treatable first-time treatment of high BP in patients without heart auses, such as renal artery disease, chronic kidney disease, disease; meta-analyses suggest an association with increased r obstructive sleep apnea. risk of cardiovascular events and death. 2 Symptomatic stage prevention and therapy are aimed at In the heart Outcomes Prevention Evaluation(HOPE) reducing systolic BP to less than 140 mm Hg, reducing dia trials, investigators found clear evidence that ACE inhibitors tolic BP to less than 90 mm Hg, and monitoring patients to can prevent deaths caused by MI and stroke and can reduce nsure that these levels are maintained. The goal is to prevent the mortality in many groups of high-risk cardiac patients damage to the organs at risk from hypertension to prevent However, ACE inhibitors should not be used in patients who disability, organ failure, and death. For patients with any might become pregnant( due to the risk of birth defects)or of hypertension, the following lifestyle modifications in patients who have bilateral renal artery stenosis dicated: weight reduction, increased physical activity, and institution of a healthy diet. In the Dietary Approaches D. Diabetes Mellitus to Stop Hypertension(DASH)trials, investigators found that instituting a diet that was rich in fruits, vegetables, grains, More than 26 million people in the United States have dia- and nonfat dairy products was associated with a reduction betes, and this number is rising. If current trends continue, in systolic BP, and even greater BP reductions were seen if one in three adults will have diabetes by 2050. About 5% sodium intake was restricted to no more than 1200 mg/day. of diabetic patients have type 1 diabetes mellitus, a disease Other dietary measures to reduce BP include the moderation that requires lifelong treatment with insulin and places them of alcohol intake and an increase in the intake of potassiun at higher risk for a variety of cardiovascular, renal, and other lcium, and magnesium Smokers should be encouraged serious complications. The remaining 95% of patients have stop smoking, because smoking cessation reduces the risk type 2 diabetes mellitus, usually associated with obesity and damage to many of the sam hat hypertension insulin resistance Much can be done to prevent ta For patients whose BP levels remain elevated despite these diabetes, as shown in the landmark Diabetes Control and estyle modifications, use of one or more antihypertensive Complications Trial (DCCT)and the United Kingdom Pro medications is indicated, Because most hypertension is spective Diabetes Study(UKPDS) In patients with type 1 asymptomatic, providers must counsel patients about the diabetes, DCCT showed that improved control of blood importance of taking medications and the risks of stopping glucose levels significantly reduced the incidence of micro- treatment. The major classes of effective antihypertensive vascular disease(retinopathy, nephropathy, neuropathy) agents include diuretics, beta blockers, angiotensin- and reduced the incidence of macrovascular disease(ath converti g enzyme(ACE) inhibitors, angiotensin receptor erosclerosis of large blood vessels, MI, angina pectoris, blockers(ARBs), calcium channel blockers, alpha blockers, stroke, aneurysm, amputations of distal lower extremity). 32