TUESDAY, April 10 (HealthDay News) -- Although research has suggested that the blood pressure drug losartan (Cozaar) may be tied to an increased risk of death in heart-failure patients compared to a similar medication, a new study finds that's not the case.

"Use of this and other similar drugs has been shown to reduce morbidity and mortality in patients with heart failure," said Dr. Gregg Fonarow, co-director of the Preventative Cardiology Program at the University of California, Los Angeles, and director of the Ahmanson-UCLA Cardiomyopathy Center, commenting on the study results.

An earlier observational study in patients with heart failure suggested that losartan was associated with higher risk of death compared to the drug candesartan (Atacand), he said.

"There were, however, a number of limitations to this prior study that could have biased these results, including differences in dosing and treating physicians," said Fonarow, who was not involved in the studies.

The new research, conducted in Denmark, finds no meaningful difference in survival among heart failure patients treated with losartan or candesartan, he said.

"This study also finds for both agents that the use of higher doses, as recommended in guidelines, is associated with better outcomes than the use of lower doses," Fonarow said.

The report was published in the April 11 issue of the Journal of the American Medical Association.

Heart failure, also called congestive heart failure, means the heart is unable to pump blood to the rest of the body the way it should.

For the study, Henrik Svanstrom, from the Statens Serum Institute in Copenhagen, and colleagues collected data on nearly 6,500 heart failure patients who had recently started taking losartan (4,397 patients) or candesartan (2,082 patients).

Both are a type of drug called angiotensin II receptor blockers (ARBs).

During follow-up, 2,378 participants died -- 330 taking candesartan and 1,212 patients taking losartan, the researchers found.

However, there was no significant increased risk of all-cause death or cardiovascular death associated with losartan compared to candesartan, the researchers said.

But dosage was important, the team said. The study found twice the risk of death with low-dose losartan compared to high-dose candesartan. Medium-dose losartan and low-dose candesartan also had a higher risk of death, but high-dose losartan had no increased death risk compared to high doses of candesartan.

"Our data provide a more detailed insight into the complexity of the association between losartan use and mortality risk in heart failure," the researchers concluded.

"These findings do not support the hypothesis of differential effects of specific ARBs in patients with heart failure," they added.

Dr. David Friedman, chief of heart failure services at North Shore-LIJ Health System's Plainview Hospital in Plainview, N.Y., said, "These medications are very helpful in heart failure patients."

Friedman noted that those in the losartan group were older and sicker, which may explain why more of them died.

These patients could only tolerate lower doses of losartan, and because they were sicker they were more likely to die than patients who could tolerate higher starting doses of candesartan, he said.

More information

For more on heart failure, visit the American Heart Association.