Anticoagulation for heart failure and afib associated with reductions in mortality, but maybe not readmissions

Starting anticoagulation for older patients with heart failure and atrial fibrillation at hospital discharge was associated with improved mortality at 1 and 3 years but was not associated with improved rates of all-cause cardiovascular readmission or stroke, a study found.

Using Get With The Guidelines-Heart Failure Registry data and Medicare claims from 2005 to 2011, researchers examined the effectiveness of anticoagulation begun at discharge in older patients hospitalized with heart failure and atrial fibrillation. Results appeared at Circulation: Cardiovascular Quality and Outcomes on Sept. 9.

Among 5,105 patients in 195 hospitals, 1,623 (31.8%) started anticoagulation at discharge. Treated patients had lower cumulative unadjusted rates of all-cause mortality (26.4% vs. 42.8%; P<0.001) and all-cause readmission (58.4% vs. 63.7%; P<0.001) at 1 year. Readmissions for heart failure, bleeding, ischemic stroke, stroke, and other cardiovascular causes were not significantly different between the groups.

After inverse weighting for the probability of treatment and adjustment for other discharge medications, anticoagulation was associated with significantly lower 1-year mortality (hazard ratio [HR], 0.70; 99% CI, 0.59 to 0.82), but the difference in readmissions was no longer statistically significant (HR, 0.89; 99% CI, 0.78 to 1.01). Results were similar at 3 years and for older patients, patients in racial/ethnic minority groups, and patients with background antiplatelet therapy, the researchers noted.

“Given how frequently heart failure and atrial fibrillation coexist, there is increasing interest in how clinical trial results translate into clinical practice and to what extent benefits are observed in understudied populations,” the researchers wrote. “We observed a mortality rate >40% at 1 year and ≅70% by 3 years among untreated patients with heart failure and atrial fibrillation. Given the overall mortality risk among older patients with heart failure, our finding of lower risk with anticoagulation therapy deserves further study, especially with the emergence of warfarin alternatives that may be easier to administer.”