A new study of 6,500 patients, published in the April 11 issue of JAMA, shows that losartan, a primary drug for hypertension, is not linked to a higher all-cause death or cardiovascular death, in comparison with ARB candesartan. Observational studies had indicated that losartan was likely to be linked to a higher mortality rate amongst patients with heart failure than other medications in the same class of drugs, such as angiotensin II receptor blockers [ARBs].
Henrik Svanstrom, M.Sc., of Statens Serum Institut in Copenhagen, Denmark, and his team decided to examine whether losartan is linked to a higher all-cause death rate in heart failure patients, as compared with candesartan.
The team used data from 6,479 patients from a nationwide Danish registry aged 45 years and older with first-time hospitalization for heart failure in 1998-2008 and cross-referenced individual-level information on hospital contacts with filled prescriptions and potential factors, which can affect outcomes. They included new losartan and candesartan users, with the final study group consisting of 2,082 candesartan users and 4,397 losartan users.
2,378 patients died during the follow-up, of which 330 deaths occurred during ongoing candesartan use and 1,212 during ongoing losartan use. The team observed that losartan use posed no substantially higher death risk than using candesartan. Furthermore, losartan was not related to a substantially higher risk of cardiovascular mortality in comparison with candesartan.
However, the researchers did establish that low-dose losartan of 12.5 mg was linked to a more than double the risk of mortality, as compared with high doses of candesartan that consisted of 16-32 mg. A medium dose of losartan, i.e. 50 mg of losartan was also related to a higher death risk, unlike a high-dose of losartan of 100 mg, which also showed no higher risk.
The researchers state that in comparison with earlier observational studies, "our data provide a more detailed insight into the complexity of the association between losartan use and mortality risk in heart failure."
The conclude, saying:
"This large, nationwide cohort study of patients with heart failure found no significantly increased risk of all-cause mortality associated with use of losartan as compared with candesartan. Whereas lower doses of losartan were associated with increased mortality risk, as compared with higher doses of candesartan, there was a decreasing risk of mortality with increasing losartan dose; and no significantly increased mortality risk was observed when comparing the highest dose of losartan against the highest doses of candesartan. These findings do not support the hypothesis of differential effects of specific ARBs in patients with heart failure."
Written By Petra Rattue