Low-dose aspirin not associated with improved outcomes in heart failure without afib
A total of 5,450 patients were using low-dose aspirin at baseline, and of these, 3,840 were propensity-matched to nonaspirin users in a 1:1 ratio.
In patients with heart failure and no history of atrial fibrillation, low-dose aspirin use did not reduce a composite outcome of all-cause mortality and admission for myocardial infarction or stroke and was linked to an increased risk of readmission for heart failure, a study found.
The study included 12,277 patients with new-onset heart failure and no history of atrial fibrillation from 2007 to 2012. A total of 5,450 patients were using low-dose aspirin at baseline, and 3,840 were propensity matched to nonaspirin users in a 1:1 ratio. The primary composite outcome included all-cause mortality, myocardial infarction, and stroke, and the secondary outcomes were bleeding and heart failure readmission. Patients were followed for a median of 1.7 years. Results of the study were published in the February JACC: Heart Failure.
The composite outcome occurred in 1,554 (40.5%) patients in the aspirin group and 1,604 (41.8%) patients in the nonaspirin group. Aspirin use was not associated with any difference in the composite outcome (hazard ratio [HR], 0.98; 95% CI, 0.91 to 1.05) but was associated with an increased risk of myocardial infarction (HR, 1.34; 95% CI, 1.08 to 1.67). No differences were noted in all-cause mortality and stroke or in bleeding. In subgroup analyses of patients with a history of ischemic heart disease, the results were similar to the main results.
The aspirin group had an increased risk for heart failure readmission (HR, 1.25; 95% CI, 1.17 to 1.33). The study authors calculated that the number needed to harm was 48. The higher risk of heart failure readmission in the aspirin group could be partly explained by impaired renal function caused by aspirin, which subsequently could contribute to salt and water retention and worsened heart failure, the authors said. Although the study's results could be affected by residual confounding, it seems biologically plausible that aspirin could increase the risk of readmission, they added.
The authors noted that no association between low-dose aspirin and reduced risk of the composite endpoint of death, myocardial infarction, and stroke was found. “The findings cast further doubt on the benefit associated with the use of aspirin in patients with [heart failure]. A prospective, randomized clinical trial could be relevant,” they said.
An editorial noted that most heart failure patients discharged from the hospital in sinus rhythm are not prescribed aspirin, including one-third or more of those with ischemic heart disease. “Therefore, it seems that a randomized controlled trial is feasible to ensure that aspirin is either given or withheld appropriately based on evidence,” the editorial said.