Decreased vagal activity and deviation in sympathetic activity precedes development of diabetes

The objective of this study was to examine whether altered heart rate variability (HRV) could predict the risk of diabetes in Asians.

RESEARCH DESIGN AND METHODS

A cohort study was conducted in 54,075 adults without diabetes who underwent three-minute HRV measurement during health check-ups between 2011 and 2014 at Kangbuk Samsung Hospital. We analyzed the time domain [standard deviation of the normal-to-normal interval(SDNN) and root mean square difference(RMSSD)] and the frequency domain [total(TP), normalized low-frequency(LF), and normalized high-frequency(HF) power, and LF/HF ratio]. We compared the risk of diabetes until 2017 according to tertiles of heart rate and HRV variables, with tertile 1 serving as the reference group.

RESULTS

During 243,758.2 person-years, 1,369 subjects were diagnosed with diabetes. Both time and frequency domain variables were lower in the diabetes group, with the exception of those with normalized LF and LF/HF ratio. In Cox analysis, as SDNN, RMSSD, and normalized HF tertiles increased, the risk of diabetes decreased [hazard ratios (95% confidence intervals) of tertile 3: 0.81 (0.70-0.95), 0.76 (0.65-0.90) and 0.78 (0.67-0.91), respectively], whereas the risk of diabetes increased in the case of heart rate, normalized LF, and LF/HF ratio [hazard ratios (95% confidence intervals) of tertile 3: 1.41 (1.21-1.65), 1.32 (1.13-1.53), and 1.31 (1.13-1.53), respectively] after adjusting for age, sex, body mass index, smoking, drinking, systolic blood pressure, lipid level, c-reactive protein, and homeostasis model assessment of insulin resistance.

CONCLUSIONS

Abnormal HRV, especially decreased vagal activity and deviation in sympatho-vagal imbalance to sympathetic activity, might precede incident diabetes.