Hypertensive patients

Sodium and Hypertension. Salt-free or low salt diets often are prescribed for hypertensive patients (57). However, sodium chloride increases the blood pressure in some individuals but not in others. Conversely, restriction of dietary NaCl lowers the blood pressure of some hypertensives, but not of others. Genetic factors and other nutrients, eg, Ca " and K", may be involved. The optimal intakes of Na" and K" remain to be estabUshed... 

It is well accepted that hypertension is a multifactorial disease. Only about 10% of the hypertensive patients have secondary hypertension for which causes, ie, partial coarctation of the renal artery, pheochromacytoma, aldosteronism, hormonal imbalances, etc, are known. The hallmark of hypertension is an abnormally elevated total peripheral resistance. In most patients hypertension produces no serious symptoms particularly in the early phase of the disease. This is why hypertension is called a silent killer. However, prolonged suffering of high arterial blood pressure leads to end organ damage, causing stroke, myocardial infarction, and heart failure, etc. Adequate treatment of hypertension has been proven to decrease the incidence of cardiovascular morbidity and mortaUty and therefore prolong life (176—183). 

Calcium channel blockers normalize the blood pressure in about 80% of hypertensive patients older than 60 years of age, 50% of those between 40 and 60 years of age, and only 20% of patients under 40 years of age. Thus calcium channel blockers are best for patients who are elderly and have low PRA and mosdy ineffective in patients who have high PRA. This responsiveness profile is very similar to that of the diuretics. 

Calcium channel blockers cause more pronounced lowering of blood pressure in hypertensive patients than in normotensive individuals. Generally, all calcium channel blockers cause an immediate increase in PRA during acute treatment in patients having hypertension but PRA is normalized during chronic treatment despite the sustained decrease in blood pressure. These agents also do not generally produce sodium and water retention, unlike the conventional vasodilators. This is because they produce diuretic effects by direct actions on the kidney. 

Verapamil (Table 1), the first slow channel calcium blocker synthesized to selectively inhibit the transmembrane influx of calcium ions into cells, lowers blood pressure in hypertensive patients having good organ perfusion particularly with increased renal blood flow. Sustained-release verapamil for once a day dosing is available for the treatment of hypertension. Constipation is a prominent side effect. Headache, dizziness, and edema are frequent and verapamil can sometimes cause AV conduction disturbances and AV block. Verapamil should not be used in combination with -adrenoceptor blockers because of the synergistic negative effects on heart rate and contractile force. 

Methyldopa is effective in mild, moderate, and severe hypertension but a thiazide-type diuretic is needed to overcome the fluid retaining side effect. Methyldopa has been shown to prevent and induce regression of ventricular hypertrophy in hypertensive patients. The principal side effects are sedation, drowsiness, nasal congestion, fluid retention, and in rare occasions, hemolytic anemia. 

Guanfacine. Guanfaciae, used ia patients having mild to moderate hypertension, can lower blood pressure 50/25 mm Hg (systoHc/diastoHc) ia hypertensive patients. Side effects such as sedation, dry mouth, and asthenia are less as compared to those of guanaben2 and clonidine. Guanfaciae reduces blood cholesterol and triglyceride and does not cause glucose iatolerance. 

Hypokalemia. Hypokalemia associated with thia2ide diuretic therapy has been knpHcated in the increased incidence of cardiac arrhythmias and sudden death (82). Several large clinical trials have been conducted in which the effects of antihypertensive dmg therapy on the incidence of cardiovascular complications were studied. The antihypertensive regimen included diuretic therapy as the first dmg in a stepped care (SC) approach to lowering the blood pressure of hypertensive patients. 

A third study (85) enrolled 7825 hypertensive patients (55% males and 45% females) having diastoHc blood pressures (DBP) of 99—104 mm Hg (13—14 Pa) there were no placebo controls. Forty-six percent of the patients were assigned to SC antihypertensive dmg therapy, ie, step 1, chlorthaUdone step 2, reserpine [50-55-5] or methyldopa [555-30-6], and step 3, hydralazine [86-54-4]. Fifty-four percent of the patients were assigned to the usual care (UC) sources in the community. Significant reductions in DBP and in cardiovascular and noncardiovascular deaths were noted in both groups. In the SC group, deaths from ischemic heart disease increased 9%, and deaths from coronary heart disease (CHD) and acute myocardial infarctions were reduced 20 and 46%, respectively. 

Angiotensin converting enzyme (ACE) plays a central role in cardiovascular hemostasis. Its major function is the generation of angiotensin (ANG) II from ANGI and the degradation of bradykinin. Both peptides have profound impact on the cardiovascular system and beyond. ACE inhibitors are used to decrease blood pressure in hypertensive patients, to improve cardiac function, and to reduce work load of the heart in patients with cardiac failure. 

Criteria for initiation of drug treatment now take into consideration total cardiovascular risk rather than blood pressure alone, such that treatment is now recommended for persons whose blood pressure is in the normal range but still bear a heavy burden of cardiovascular risk factors. Thus, the role of simultaneous reduction of multiple cardiovascular risk factors in improving prognosis in hypertensive patients is stressed. In addition, more aggressive blood pressure goals are recommended for hypertensive patients with comorbid conditions such as diabetes mellitus or renal insufficiency. 

Avoid alcohol and nonprescription drug s unless their use has been approved by the primary health care provider. Hypertensive patients should be careful to avoid medications that increase blood pressure, such as over-the-counter drag s for appetite suppression and cold symptoms. 

National and international trends over the past 15 years depict modest improvements in the treatment and/or control of blood pressure (BP) for hypertensive patients. This observation is made despite efforts to promote awareness, treatment, and the means available to aggressively manage high blood pressure. Over 65 million Americans have hypertension, which was listed as the primary cause of death for over 261,000 individuals in the United States in 2002.1 Hypertension is also a significant cause of end-stage renal disease and heart failure. National and international organizations continually refine their recommendations of how... 

In addition to primary and secondary hypertension, the clinician may encounter what is referred to as resistant hypertension. Patients failing to achieve goal blood pressure despite maximum doses of three antihypertensives including a diuretic should be carefully screened for resistant hypertension. Several causes of resistant hypertension are listed in Table 2-2 and should be carefully considered in such patients. 

Symptoms The primary hypertension patient may be asymptomatic or may have major cardiovascular disease risk factors. 

Laboratory Tests (Not necessarily indicative of hypertension, but may be seen in hypertensive patients)... 

Julius S, Kjeldsen SE, Weber M, et al. Outcomes in hypertensive patients at high cardiovascular risk treated with regimens based on valsartan or amlodipine the VALUE randomised trial. Lancet 2004 363(9426) =2022-2231. 

Major outcomes in high-risk hypertensive patients randomized to angiotensin-converting enzyme inhibitor or calcium channel blocker vs. diuretic The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). JAMA 2002 288(23) =2981-2997. 

There are several areas of study that will help you understand the research topic. As a first step you will want to read the clinical protocol. The protocol describes the device or medication to be used, the patient populations under study, the statistical plan of the clinical trial, and the details of the disease state. If you want to understand the disease state or indication further, you may want to seek out a clinical investigator of the clinical trial or do some further reading about the disease. Understanding the patient population is a good way to understand the data that you will see and whether there is reason for concern when viewing the data. For example, if you were studying a medication to reduce hypertension, you would not be as worried if patient blood pressure data were elevated at baseline. You would expect to see this because you understand that hypertensive patients have high blood pressure. 

Excessive lead exposure has also been implicated as a causative agent in kidney disease associated with gout and essential hypertension (Batuman et al. 1981, 1983). Gout patients with renal impairment, and hypertensive patients with renal impairment, had significantly higher lead stores (as determined by the 3-day EDTA lead mobilization test) than gout patients or hypertensive patients without renal impairment, respectively. Therefore, excessive lead absorption may be involved in the renal impairment seen in patients with gout or essential hypertension. 

Hypertension is the most common cardiovascular disease in fact, nearly 25% of adults in the U.S. are considered hypertensive. Hypertension is defined as a consistent elevation in blood pressure such that systolic/diastolic pressures are >140/90 mmHg. Over time, chronic hypertension can cause pathological changes in the vasculature and in the heart. As a result, hypertensive patients are at increased risk for atherosclerosis, aneurysm, stroke, myocardial infarction, heart failure, and kidney failure. There are several categories of antihypertensive agents ... 

Perticone F, Ceravolo R, Maio R, Ventura G, Zingone A, Perrotti N, Mat-tioli PL. Angiotensin-converting enzyme gene polymorphism is associated with endothelium-dependent vasodilation in never treated hypertensive patients. Hypertension 1998 31 900-905. 

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