Blood pressure variability is a better associated with acute relative hyperglycemia than the heart rate variability in healthy young adults.

BACKGROUND Deranged cardiovascular autonomic functions are well-reported complications of diabetes mellitus where chronic hyperglycemia is one of the important factors. But, the role of acute relative hyperglycemia on cardiovascular autonomic functions in healthy subjects is less explored. Hardly any study has reported the effect of acute hyperglycemia on blood pressure variability. Therefore, the present study was planned to study the effect of acute relative hyperglycemia on cardiovascular autonomic functions in healthy young adults. METHODS Beat-to-beat blood pressure and electrocardiogram were recorded for the assessment of heart rate variability and blood pressure variability in forty-two young, healthy subjects during fasting and relative hyperglycemic states. Recorded cardiovascular parameters were analyzed in time and frequency domains. Correlations among analyzed parameters of cardiovascular autonomic variabilities were explored during fasting and relative hyperglycemic state. RESULTS We observed significant alteration of few of the systolic, mean and diastolic blood-pressure-variability-parameters during acute relative hyperglycemia when compared to the fasting state. However, no significant changes were observed in any of the heart-rate-variability parameters. Also, we found novel significant correlations among many of the parameters of cardiovascular autonomic variabilities during fasting and relative hyperglycemic states. CONCLUSIONS Present study concludes that the blood pressure variability is affected significantly during acute relative hyperglycemia in healthy young adults, however, the heart rate variability does not show such changes. Also, many of the parameters of blood pressure variability show significant correlations with heart rate variability and baroreflex sensitivity. We may hypothesize that although the heart rate variability and blood pressure variability assess cardiovascular autonomic functions, blood pressure variability is a better indicator of cardiovascular autonomic effects of acute relative hyperglycemia than heart rate variability.