The role of autonomic neuropathy as the pivotal event in sudden cardiac death in diabetic patients needs revision. New research suggests that heart and kidney disease play bigger roles.
Diabetic autonomic neuropathy contributes less than might be expected to the risk of sudden cardiac death in patients with diabetes, according to a new report. "In our study, says Dr. Guillermo A. Suarez, coronary artery disease causing ischemia and diabetic nephropathy were the main risk factors associated with sudden cardiac death."
"This was a prospective, population based study supported by the National Institutes of Health that undertook a comprehensive analysis of putative risk factors on the outcome of sudden cardiac death in the Rochester Diabetic Neuropathy Study (RDNS) cohort," Dr. Suarez explained.
Dr. Suarez, at the Mayo Clinic College of Medicine in Rochester, Minnesota, and colleagues identified 21 cases of sudden cardiac death during 15 years of follow-up of 462 diabetic patients enrolled in the RDNS.
In a life table analysis of risk factors for sudden cardiac death, the three ECG variables (evolving and previous myocardial infarction, bundle branch block or electronic pacing) and calcification of vessels in the feet represented the largest relative hazards for sudden cardiac death, the team reports in the February Journal of Neurology, Neurosurgery, and Psychiatry
Nephropathy stage was also a significant risk factor, the authors report, but none of the autonomic scores were significant predictors of sudden cardiac death after adjustment for nephropathy stage.
All patients who died suddenly had a clinical history of atherosclerosis with clinical left ventricular dysfunction or severe coronary atherosclerosis with myocardial damage at necropsy or both, the researchers note.
"In the light of our results," the investigators conclude, "the role of autonomic neuropathy as the pivotal event in sudden cardiac death in diabetic patients probably needs revision."
It’s possible that "diabetic autonomic neuropathy may act as the transient factor conducive to the final event," they add, "but further studies are necessary to determine this."
J Neurol Neurosurg Psychiatry 2005;76:240-245.
According to NHANES 1999-2002 survey, the prevalence of overweight or obesity in diabetic men was 86.3%, and the prevalence of obesity was 53.0%. Both the prevalence of overweight or obesity and the prevalence of obesity were similar among men aged 20-64 years and 65 years. Among women in the 1999-2002 survey, the prevalence of overweight or obesity was 84.2%, and the prevalence of obesity was 58.0%. Compared with women aged 65 years, women aged 20-64 years had a significantly higher prevalence of obesity (64.7% versus 47.4%)