Benefits of Losartan in Patients with Hypertension and Left Ventricular Hypertrophy but No Vascular Disease

What is the problem and what is known about it so far?

High blood pressure (hypertension) is a chronic condition that damages blood vessels and body organs. It increases the risk for heart attacks, heart failure, strokes, and kidney failure. Doctors use many types of antihypertensive drugs to treat high blood pressure. Although the drugs may reduce blood pressure to a similar extent, their ability to prevent complications of high blood pressure may vary.

Recently, a large study in hypertensive patients with thickened heart muscle (left ventricular hypertrophy) showed that treatment with losartan (an angiotensin II receptor–blocker drug) prevented strokes more than did treatment with atenolol (a β-blocker drug). The study included high-risk patients who already had blood vessel disease (vascular disease) and lower-risk patients without vascular disease. Many researchers wondered whether losartan worked well in the lower-risk patients.

Why did the researchers do this particular study?

To assess the benefits of losartan in patients with hypertension and left ventricular hypertrophy but no vascular disease.

Who was studied?

6886 hypertensive men and women 55 to 80 years of age. All patients had heart tracings that showed left ventricular hypertrophy. No patient had known vascular disease.

How was the study done?

The researchers randomly assigned 9193 patients to receive either losartan or atenolol. Of these patients, 6886 had no previous heart, brain, or peripheral vascular disease. The patients and their doctors did not know who received which drug. Patients' blood pressures were taken regularly. If blood pressure levels were greater than 140/90 mm Hg, higher doses of losartan or atenolol or additional antihypertensive drugs were used. Patients were followed for about 5 years. During that time, the researchers routinely checked for complications, such as heart attacks and strokes.

What did the researchers find?

The losartan and atenolol groups achieved similar blood pressure reductions, but most patients in both groups needed two to three drugs to control blood pressure. Fewer patients in the losartan group had strokes and developed diabetes. Similar numbers of patients in both groups had heart attacks. More patients in the atenolol group (10%) had drug-related side effects than did patients in the losartan group (6%).

What were the limitations of the study?

The study is a subgroup analysis of a larger study. Subgroup analyses typically decrease the ability to show differences between groups in some outcomes and increase the possibility of finding some false differences. Most patients (95%) were white, and findings may not apply to black people.

What are the implications of the study?

Lower-risk, white patients with hypertension and left ventricular hypertrophy but no vascular disease benefit more from losartan-based therapy than atenolol-based therapy.