Patients with Type 2 Diabetes at Higher Risk for Sudden Cardiac Death After a Heart Attack than Nondiabetics

New Study Published in HeartRhythm Finds Type 2 Diabetes to be an Independent Risk Factor for Sudden Cardiac Death after Myocardial Infarction

October 05, 2010

Media Contact

Shane Osborne
Heart Rhythm Society
media@hrsonline.org
202-464-3431

WASHINGTON, October 5, 2010 — New research reveals that patients with type 2 diabetes are at a higher risk for sudden cardiac death (SCD) after myocardial infraction (MI) than nondiabetic patients. According to research published in the October edition of HeartRhythm , the official journal of the Heart Rhythm Society, incidence of SCD in diabetic patients with a left ventricular ejection fraction >35% is equal to that of nondiabetic patients with left ventricular ejection fraction of <35%. A secondary analysis indicated that non-sudden cardiac deaths were also higher among diabetics after a heart attack.

Between 1996 and 2005, researchers followed a cohort of 3,276 patients enrolled into the study at the time of acute MI. At entry into the study, diabetes was present in 629 (19.2 %) patients. Type 2 diabetes diagnosis was based upon World Health Organization criteria for the disease. Patients with type 1 diabetes and patients with cardiac arrest during or prior to index MI were excluded from the study. During long-term follow-up of five years, outcomes for patients with type 2 diabetes were observed and compared to the nondiabetic patient population after MI.

Study findings show that SCD occurred in 5.9% of the diabetic patient population compared to 1.7% of the nondiabetic patient subgroup. The cumulative all-cause mortality rate among the diabetic population was 21% compared to 8.4% among the nondiabetic population. After adjustments for gender, age, hypertension, prior MI, LVEF and other factors, study analysis found type 2 diabetes to be an independent predictor of SCD. In a subgroup analysis comparing patients with left ventricular ejection fraction <35% versus those >35%, the incidence of SCD among diabetic patients with LVEF >35% was nearly identical to that of nondiabetic patients with LVEF <35%.

“A striking result from our study is the observance of equivalent SCD risk between diabetic patients with ejection fraction >35% and nondiabetic patients with ejection fraction <35%,” said lead author Juhani Junttila, MD, Division of Cardiology, University of Miami Miller School of Medicine in Miami, Fla. “These observances may have implications for the interpretation of evidence-based criteria for ICD therapy after MI, but further studies are needed to determine whether type 2 diabetic patients who have had an MI would benefit from modifications of ICD guidelines.”

According to the Heart Rhythm Society, more than 250,000 people die every year as a result of Sudden Cardiac Arrest (SCA). To raise awareness about SCA, the Heart Rhythm Society created the “Apples and Oranges” ongoing awareness campaign designed to educate people about SCA and what can be done to help save lives.  In addition, the October edition of HeartRhythm has a special focus on SCA and SCD.  This study is one of the many included that covers procedures, treatments and outcomes specific to SCA and SCD.

About the Heart Rhythm Society

The Heart Rhythm Society is the international leader in science, education and advocacy for cardiac arrhythmia professionals and patients, and the primary information resource on heart rhythm disorders. Its mission is to improve the care of patients by promoting research, education and optimal health care policies and standards. Incorporated in 1979 and based in Washington, DC, it has a membership of more than 5,900 heart rhythm professionals in more than 70 countries around the world. For more information, visit www.HRSonline.org .