Valsartan

* EVIDENCE-BASED ANSWER

Low-dose thiazide diuretics (eg, hydrochlorothiazide 12.5 to 25 rag/d) are the best first-line pharmacotherapy for treating uncomplicated hypertension (strength of recommendation [SOR]: A, based on randomized trials [RCTs] and 1 meta-analysis). Alternate first-line agents include angiotensin-converting enzyme (ACE) inhibitors, beta blockers, and calcium channel blockers (SOR: A, based on RCTs).

* EVIDENCE SUMMARY

Three landmark placebo-controlled studies have established that thiazide diuretic-based treatment reduces morbidity and mortality among patients with hypertension, (1-3) Based on these data, thiazide diuretic therapy is considered the gold-standard treatment for uncomplicated hypertension.

Several other clinical trials have subsequently compared the effect of thiazide diuretics with that of other antihypertensive agents (beta-blockers, calcium channel blockers, and alpha-blockers) on patient-oriented outcomes. These were analyzed in a recent meta-analysis of 42 clinical trials that included 192,478 patients randomized to 7 treatment strategies including placebo. (4) Results from the largest antihypertensive clinical trial, the Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT), were included in this meta-analysis. (5) Comparative results are depicted in the Table. Although these data showed no differences between drug therapies in total and cardiovascular disease mortality, low-dose diuretics reduced certain cardio-vascular endpoints (ie, heart failure, stroke, cardiovascular disease events) more than other drug therapies.

Angiotensin receptor blockers (ARBs) have not been compared with thiazide diuretics in a trial. Two long-term trials have compared an ARB to other types of drug therapy: losartan vs atenolol in the Losartan Intervention for Endpoint Reduction (LIFE) trial, (6) and valsartan vs amlodipine in the Valsartan Antihypertensive Long-term Use Evaluation (VALUE) trial. (7) In the LIFE trial, the primary composite endpoint of cardiovascular death, myocardial infarction, and stroke was less with losartan than atenolol (23.8 vs 27.9 events per 1000 patient-years, losartan and atenolol, respectively; number needed to treat=243 people-years, P=.021). (6) However, in the VALUE trial, the primary endpoint of time to cardiac event was not different between valsartan and amlodipine (25.5 vs 24.7 events per 1000 patient-years, valsartan and amlodipine, respectively; P=.49). (7)

* RECOMMENDATIONS FROM OTHERS

The Seventh Report of the Joint National Committee (JNC7) recommended thiazide diuretics as preferred initial agents in uncomplicated hypertension? The European Society of Hypertension/European Society Cardiology recommended either a diuretic, beta-blocker, calcium channel blocker, ACE inhibitor, or ARB for initial therapy stating that blood pressure control to recommended values via any agent is more important than the type of agent used? Both guidelines identified other antihypertensives that may be used in addition to or in place of thiazide diuretics for compelling indications, such as heart failure, diabetes, high-risk cardiovascular disease, chronic kidney disease, post-myocardial infarction, and secondary stroke prevention.

REFERENCES

(1.) Prevention of stroke by antihypertensive drug treatment in older persons with isolated systolic hypertension. Final results of the Systolic Hypertension in the Elderly Program (SHEP). SHEP Cooperative Research Group. JAMA 1991; 265:3255-3264.

(2.) Medical Research Council trial of treatment of hypertension in older adults: principal results. MRC Working Party. BMJ 1992; 304:405-412.

(3.) Dahlof B, Lindholm LH, Hansson L, Schersten B, Ekbom T, Wester PO. Morbidity and mortality in the Swedish Trial in 01d Patients with Hypertension (STOP-Hypertension). Lancet 1991; 338:1281-1285.

(4.) Psaty BM, Lumley T, Furberg CD, et al. Health outcomes associated with various antihypertensive therapies used as first-line agents: a network meta-analysis. JAMA 2003; 289:2534-2544.

(5.) ALLHAT Officers and Coordinators for the ALLHAT Collaborative Research Group. The Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial. Major outcomes in high risk hypertensive patients randomized to augiotensin-converting enzyme inhibitor or calcium channel blocker vs diuretic: The Antihypertensive and Lipid Lowering Treatment to Prevent Heart Attack Trial (ALLHAT). JAMA 2002; 288:2981-2997.

(6.) Dahlof B, Devereux RB, Kjeldsen SE, et al. Cardiovascular morbidity and mortality in the Losartan Intervention For Endpoint reduction in hypertension study (LIFE): a randomised trial against atenolol. Lancet 2002; 359:995-1003.

(7.) 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; 363:2022-2031.

(8.) Chobanian AV, Bakris GL, Black HR, et al. Seventh report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure. Hypertension 2003; 42:1206-1252.

(9.) European Society of Hypertension--European Society of Cardiology Guidelines Committee. 2003 European Society of Hypertension-European Society of Cardiology guidelines for the management of arterial hypertension. J Hypertens 2003; 21:1011-1053.

* CLINICAL COMMENTARY

Thiazide diuretics: first or second agent for patients with hypertension

Skeptics argue that other antihypertensives are equal to thiazides. However, thiazides are the least expensive agents (1-year hydrochlorothiazide 25 mg/d is <$25.00). This aspect of therapy supports thiazides as first-line pharmacotherapy. The debate of which agent to use first may be moot considering most hypertensive patients require 2 or more drugs to achieve a systolic blood pressure goal of <140 mm Hg. In addition, the JNC7 recommended starting with 2 agents for patients far from their blood pressure goal (eg, systolic blood pressure [greater than or equal to] 160 mm Hg). Therefore, even if a thiazide is not the initial agent (because of preference or other compelling indications) it should be the second agent for most patients.

Joseph J. Saseen, PharmD, FCCP, Chad Turner, MD, University of Colorado Health Sciences Center, Denver; Roger G. Russell, MLS, AHIP, Laupus Health Sciences Library, East Carolina University, Greenville, NC

COPYRIGHT 2005 Dowden Health Media, Inc.
COPYRIGHT 2005 Gale Group