Cardiac Autonomic Neuropathy Linked to Silent Heart Attacks in diabetes patients

Despite significant strides in diabetes research, there remains a notable gap in understanding the link between cardiac autonomic neuropathy (CAN) and the risk of silent myocardial infarction (SMI) in individuals with type 2 diabetes. A groundbreaking study, drawing from a large sample of adults with type 2 diabetes in the ACCORD (Action to Control Cardiovascular Risk in Diabetes) study, has shed light on this crucial association and revealed a significant association between CAN and an increased risk of incident silent myocardial infarction (SMI).

The study results were published in the Journal of the American Heart Association. 

The study focused on participants without atherosclerotic cardiovascular disease at the study's commencement. CAN, a condition affecting the nerves that control the heart, was assessed using heart rate variability indices derived from 10-second resting electrocardiograms. Specifically, CAN was defined as having both the standard deviation of all normal-to-normal R-R intervals and the root mean square of successive differences between normal-to-normal R-R intervals falling below the fifth percentile of the general population.

Key Findings:

• Over a median follow-up of 4.9 years, involving 4842 participants with type 2 diabetes (mean age, 62.5 years; 46.6% women; 60.2% White), 73 incident cases of silent myocardial infarction occurred.
• The incidence rate was 3.1 out of 1000 person-years.
• After meticulous adjustments for potential confounders, the study revealed a noteworthy association between low heart rate variability and an increased risk of silent myocardial infarction.
• Participants with both low standard deviation of all normal-to-normal R-R intervals and low root mean square of successive differences between normal-to-normal R-R intervals had hazard ratios of 1.67 and 1.56, respectively.
• Most significantly, individuals with CAN were found to have a 1.9-fold greater risk of experiencing silent myocardial infarction, providing a crucial link between diabetic nerve conditions and cardiovascular events.

This groundbreaking research underscores the importance of recognizing and addressing cardiac autonomic neuropathy in individuals with type 2 diabetes. Identifying CAN early could be a key factor in predicting and preventing silent myocardial infarctions, thereby reducing the overall cardiovascular risk in this population. The findings call for increased awareness among healthcare professionals and individuals with diabetes about the potential risks associated with cardiac autonomic neuropathy. Additionally, the study sets the stage for further investigations into preventive measures and interventions targeting CAN to mitigate the risk of silent myocardial infarctions in individuals with type 2 diabetes.

Further research: Cardiac Autonomic Dysfunction and Risk of Silent Myocardial Infarction Among Adults With Type 2 Diabetes. https://doi.org/10.1161/JAHA.123.029814