Screening for Asymptomatic Coronary Artery Disease in Patients with Type 2 Diabetes
Dr. L.H. Young and colleagues reported the lack ofutility of MPI for predicting myocardial events in the DIADstudy.1 However, the article contained information that suggestsa simpler and possibly more effective means of predicting cardiovascularevents.
Advertisement
The results showed that the age- and sex-adjusted hazard ratio for the lowestquartile of cardiac autonomic dysfunction was 4.33 (95% confidenceinterval, 2.14-8.75; P < .001). A previous articlefrom this group2 reported that an autonomic function test thatmeasures the Valsalva ratio (which incorporates cardiac parasympatheticand sympathetic nervous system activity) was a strong predictorof myocardial ischemia (which may be silent).
The study by Younget al reported results of change in heart rate from lying down tostanding, indicating that the presence of cardiac autonomicdysfunction had one of the highest hazard ratios associatedwith the primary events, greater than many of the other clinicalfactors. In addition, numbness and absence of sensation, whichare indices of peripheral neuropathy, had hazard ratios of 2.23and 2.83, respectively (P < .05 for both). It thereforeseems that greater attention to autonomic function should beconsidered.
It is feasible to quantify not only autonomic neuropathy butan imbalance between the sympathetic and parasympathetic nervoussystems.4 An imbalance might be conducive to cardiac arrhythmiasand premature death. The benefit of doing a stress thalliumtest in patients with autonomic dysfunction is an open question.It would be interesting to see whether scoring of high- versus low-riskpatients in the DIAD study based on their autonomic dysfunctionmerits reexamination and perhaps revision of the American DiabetesAssociation guidelines on risk factors for major adverse cardiovascularevents.5
1. Young LH, Wackers FJ, Chyun DA; et al, DIAD Investigators. Cardiac outcomes after screening for asymptomatic coronary artery disease in patients with Type 2 diabetes: the DIAD study: a randomized controlled trial. JAMA. 2009;301(15):1547-1555. FREE FULL TEXT
2. Wackers FJ, Young LH, Inzucchi SE; et al, Detection of Ischemia in Asymptomatic Diabetics Investigators. Detection of silent myocardial ischemia in asymptomatic diabetic subjects: the DIAD study. Diabetes Care. 2004;27(8):1954-1961. FREE FULL TEXT
DISCLAIMER: The content of this Website is independent of the views of our advertisers and sponsors. The site is designed primarily for use by qualified physicians and other medical professionals. The information contained herein should NOT be used as a substitute for the advice of an appropriately qualified and licensed physician or other health care provider. The information provided here is for educational and informational purposes only. In no way should it be considered as offering medical advice. Please check with a physician if you suspect you are ill.
Copyright @ 1999-2013 Diabetes In Control, Inc.. All rights reserved.
