Rapid glucose rise reduces heart rate variability in adults with type 1 diabetes: A prospective secondary outcome analysis

Abstract

To investigate differences in heart rate variability (HRV) during oral glucose tolerance tests (OGTTs) in response to the rate of change in glucose and to different glycaemic ranges in individuals with type 1 diabetes. This was a single-centre, prospective, secondary outcome analysis in 17 individuals with type 1 diabetes (glycated haemoglobin 53 ± 6.3 mmol/L), who underwent two OGTTs (after 12 and 36 hours of fasting) investigating differences in HRV in response to rapid glucose increases/ decreases and different glycaemic ranges during OGTT. Based on the rate of change in glucose level, the variables heart rate (P < 0.001), square root of the mean standard difference of successive R-R intervals (P = 0.002), percentage of pairs of R-R intervals with >50 ms difference (P < 0.001) and corrected QT interval (P = 0.04) were significantly altered, with HRV particularly reduced during episodes of rapid glucose rises.Glycaemic ranges during OGTT had no impact on HRV (P < 0.05). Individuals with type 1 diabetes showed no changes in HRV in response to different glycaemic ranges. HRV was dependent on the rate of change in glucose, especially rapid increases in glucose level.

Acute Changes in Heart Rate Variability to Glucose and Fructose Supplementation in Healthy Individuals: A Double-Blind Randomized Crossover Placebo-Controlled Trial

“…This indicates a more metabolically induced response leading to a significant increase in cardio-autonomic stress. This is entirely contrary to what was seen previously in individuals with T1DM recently shown by our study group [ 15 ]. Neither heart rate, SDNN, RMSSD nor pNN50% were significantly altered following an oral glucose tolerance test in that study [ 15 ].…”

“…This is entirely contrary to what was seen previously in individuals with T1DM recently shown by our study group [ 15 ]. Neither heart rate, SDNN, RMSSD nor pNN50% were significantly altered following an oral glucose tolerance test in that study [ 15 ]. It can be suspected that individuals with T1DM spend more time in either hypo- or hyperglycemia compared to healthy individuals due to the complex insulin management.…”

“…For the purpose of this study we stratified glucose levels according to recent position statements on BG monitoring and previously published data [ 14 , 15 ]. BG levels were merged with HRV data for analysis.…”

“…We have recently shown that in individuals with T1DM without cardiac autonomic neuropathy, rapid increases in blood glucose lead to significant short-term reductions in HRV [ 15 ]. This was somewhat surprising since previous research has merely focused on glycemic ranges.…”

“…Since cardiac autonomic responses, detected via HRV have been subject of investigation for several decades under resting and exercise conditions [ 19 , 20 , 21 ], it is of interest how metabolic stress induces a cardiac autonomic response. To the best of our knowledge research has solely been conducted in individuals with T1DM and T2DM [ 12 , 15 , 22 ], investigating the effects of glycemia and HRV. Consequently, the aim of this study was to investigate how different types of fluid carbohydrates consumed via an individualized amount influence blood glucose levels and lead to a cardiac autonomic response measured via HRV in a double-blind randomized placebo-controlled fashion.…”