UCLA researchers for the first time showed that advanced heart failure patients with diabetes who are treated with insulin faced a mortality rate four times higher than heart failure patients with diabetes treated with oral medications.The new study may help raise awareness among physicians and patients of this previously unknown relationship between insulin use and increased mortality in advanced heart failure patients. More research is needed to explore the mechanisms of how insulin use may be contributing to the higher mortality rate.
The research appears in the January issue of the peer reviewed American Heart Journal.
Previous studies have shown a connection between type 2 diabetes, heart failure and insulin. The UCLA study is the first to identify a high mortality rate for advanced heart failure patients who use insulin to manage diabetes. "Further studies into what is the best strategy to control blood sugar levels in patients with diabetes and heart failure are urgently needed," said Fonarow. Dr. Gregg Fonarow, senior study author; professor of cardiology, David Geffen School of Medicine at UCLA; and director, Ahmanson-UCLA Cardiomyopathy Center.
Researchers assessed the history of diabetes and insulin treatment in 554 patients with advanced heart failure after adjusting for various risk factors. One year survival rates were 89.7 percent for non-diabetic patients, 85.8 percent for non-insulin-treated diabetic patients, and only 62.1 percent for insulin-treated diabetic patients.
Heart failure affects 5 million in the United States and is the most common cause of hospitalization for those 65 years and older. Between 25 to 44 percent of heart failure patients also have diabetes.
The study is funded by the Ahmanson Foundation and was conducted at UCLA. Fonarow is a research consultant and speaker for GlaxoSmithKline, Bristol-Myers Squibb, Pfizer and Merck.