February 17, 2016 – Prateeti Khazanie, MD, MPH, and her colleagues found that hydralazine-isosorbide dinitrate was rarely prescribed by doctors.
Although current guidelines recommend the use of hydralazine–isosorbide dinitrate (H-ISDN) for heart failure patients, a new study by DCRI researchers has found that it is not prescribed very often. Moreover, adherence rates for patients who are prescribed the therapy tend to be low.
The study, which appears in the journal Circulation: Heart Failure, also found no difference in clinical outcomes between patients who received H-ISDN and those who did not.
Previous research has suggested that H-ISDN is useful for treating heart failure patients with reduced ejection fraction, particularly black patients and patients with intolerance to angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers. Consequently, current guidelines from both the American College of Cardiology/American Heart Association and the Heart Failure Society of America include H-ISDN as a class I recommendation for heart failure patients of all races.
However, doctors have been generally slow to adopt H-ISDN treatment for their patients. This may be because of concerns that the treatment might be less effective in the general population than in clinical trial cohorts, which are carefully selected and receive protocol-driven care and follow-up.
In an observational study, a team of researchers led by the DCRI’s Prateeti Khazanie, MD, MPH (pictured), examined the use of H-ISDN therapy among heart failure patients and its associations with outcomes among black patients and patients of other races. Using data from American Heart Association’s Get With The Guidelines-Heart Failure (GWTG-HF) registry linked with Medicare claims, the researchers identified 12,300 patients aged 65 years or older who received treatment for heart failure between 2005 and 2011. Of this original study population, 4,663 patients were deemed eligible for H-ISDN treatment.
Among eligible patients, just 22.7 percent of black patients and 18.2 percent of patients not on an angiotensin-converting enzyme inhibitor or angiotensin II receptor blockers were prescribed H-ISDN therapy. Adherence rates for patients who were prescribed H-ISDN therapy were also low among patients of all races, with more than half of patients who were discharged on the therapy not filling an prescription for the therapy within 90 days. The researchers’ analysis of outcomes found that H-ISDN therapy was not associated with lower rates of mortality, all-cause readmission, or cardiovascular readmission.
The researchers concluded that their findings illustrate the need to implement guideline-directed medical therapies in a manner that replicates as closely as possible the treatments observed in clinical trial settings and the need to ensure that clinical trial evidence is broadly generalizable.
Other DCRI authors on the study included Li Liang, PhD; Lesley H. Curtis, PhD; Zubin J. Eapen, MD; Eric D. Peterson, MD, MPH, and Adrian F. Hernandez, MD, MHS.