For nearly 6,000 patients with heart failure and chronic kidney disease (CKD), the use of an implantable cardioverter defibrillator (ICD) showed no mortality benefit but a higher risk of subsequent hospitalizations after covariate adjustment, researchers reported in JAMA Internal Medicine.
"The finding surprised us," lead author Nisha Bansal, MD, MAS, with the division of nephrology at University of Washington, said in a press release. "Chronic kidney disease is common in adults with heart failure and is associated with a greater risk of heart attack. However, in this observational study, we did not find a significant overall benefit from ICDs for patients with kidney disease."
Indeed, more than 5.7 million adults have heart failure and 30 percent of those have CKD, according to the authors. But while ICDs have been shown to reduce the risk of arrhythmic death in randomized trials of heart failure patients, the researchers pointed out patients with CKD are underrepresented in those studies.
“Because ICD placement carries risks and is expensive, a better understanding of how best to use this therapy in high-risk subgroups such as patients with CKD is critical,” they wrote.
Bansal and coauthors studied 5,877 adults with CKD and heart failure with a left ventricular ejection fraction of 40 percent or less. Among the study population—68.9 percent men; mean age 72.9—1,556 received an ICD and 4,321 didn’t.
After adjusting for demographics, comorbidities and medication use, the researchers noted a 4 percent decrease in all-cause death in the ICD group, but the difference didn’t reach statistical significance. However, over the average follow-up of 3.1 years, all-cause hospitalizations were 25 percent higher in the ICD group and heart failure-related hospitalizations were 49 percent higher.
“Hospitalizations are an important outcome to patients as a quality of life measure and pose substantial economic burdens to the health care system,” the researchers wrote. “Patients with CKD are known to have a disproportionate burden of hospitalizations and recurrent hospitalizations even without placement of cardiac devices.”
Bansal et al. said their findings could help guide clinical decision-making when it comes time consider ICDs in patients with heart failure and CKD—particularly because there is a lack of sizable, randomized trials evaluating ICD use in this population.
The authors noted their patients largely had moderate stages of CKD, so the findings may not be generalizable to patients with other severities. In addition, they couldn’t determine the causality of their endpoints, suggesting the need for a future randomized trial.