Even minor weight loss is associated with worse health outcomes among patients implanted with cardiac resynchronisation therapy with defibrillator (CRT-D), according to research presented by Valentina Kutyifa, postdoctoral research associate at the University of Rochester Medical Center, Rochester, USA, at the American College of Cardiology’s (ACC) 62nd Annual Scientific Session.
People with symptoms of heart failure who have an implantable CRT-D device may believe that losing weight will ultimately improve their long-term health outcomes. However, in the first study to look at weight loss and subsequent health outcomes among patients with a CRT-D, researchers found the opposite may be true.
“In patients with heart failure who receive a cardiac resynchronisation device with defibrillator, unintended weight loss of just five pounds increases the risk of a serious cardiac event,” said Kutyifa, who is the lead author of the MADIT-CRT (Multicenter automatic defibrillator implantation with cardiac resynchronisation therapy) trial. “These findings suggest clinicians should be monitoring patients with unplanned weight loss more closely.”
Among the subset of patients who had left bundle branch block, the risk of heart failure or death with weight loss doubled.
In this study, nearly 1,000 patients who received a CRT-D were observed at 12 months after implantation. Of these, nearly one in five (17%) had lost more than two kilograms, or 4.4 pounds, during that time. These patients had a significant increase in their risk of heart failure or death compared to those without significant weight loss. In fact, each kilogram (2.2 pounds) of weight lost correlated to a 4% higher risk of heart failure or death.
This research fits with other studies that have looked at the “obesity paradox,” wherein overweight patients with chronic diseases such as heart disease, kidney disease or diabetes, have better health outcomes than those of normal weight. One reason for this paradox among CRT-D patients might be that heart failure causes the body to be in a catabolic state, meaning it has a high demand for energy. Heart failure patients without significant weight loss may have reserves that better allow their bodies to tolerate this high energy demand, Kutyifa said.
Study authors caution that their findings are not a prescription for patients to pack on the pounds.
“We would still recommend weight control under a physician’s supervision since we know that obesity is associated with other serious diseases including diabetes, high blood pressure, coronary artery disease and sleep apnea,” Kutyifa said. “Heart failure patients should continue to follow their clinicians’ advice in regards to diet and lifestyle changes.”
According to Kutyifa, more research is needed to examine the effects of weight loss among heart failure patients with pacemakers in prospective clinical trials. The MADIT-CRT trial was supported by a research grant from Boston Scientific.