Association between hypoglycaemic glucose variability and autonomic function in type1 diabetes with impaired hypoglycaemia awareness. (July 2022)

• Record Type: Journal Article
• Authors: Racca, Caterina; Bouman, Emma J.; Van Beers, Cornelis A.J.; Smits, Mark M.; van Raalte, Daniel H.; Serné, Erik H.
• Is Part Of: Diabetes research and clinical practice. Volume 189(2022)
• Publication Date: 2022-07
• Subjects: Cardiovascular autonomic neuropathy -- Continuous glucose monitoring -- Glucose variability -- Heart rate variability -- Impaired awareness of hypoglycaemia -- Low blood glucose index; CAN cardiovascular autonomic neuropathy -- CARTs cardiovascular autonomic reflex tests -- CGM continuous glucose monitoring -- CONGA continuous overall net glycaemic action -- CSII continuous subcutaneous insulin infusion -- EURODIAB IDDM microvascular and acute complications study in people with insulin dependent diabetes mellitus in Europe -- GRADE glycaemic risk assessment diabetes equation -- GV glucose variability -- HBGI high blood glucose index -- HFpower high frequency power of heart rate variability -- HRV heart rate variability -- IAH impaired awareness of hypoglycaemia -- IN CONTROL continuous glucose monitoring for patients with type 1 diabetes and impaired awareness of hypoglycaemia: a randomised, open-label, crossover trial -- LBGI low blood glucose index -- LFpower low frequency power of heart rate variability -- MAG mean average glucose -- MAGE mean amplitude of glycaemic excursions -- MDI multiple daily insulin injections -- MODD mean of daily differences -- RMSSD root mean square of the successive differences -- RR interval interval between R-waves on the ECG -- SDRR standard deviation of RR-intervals -- SMBG self-monitoring of blood glucose -- T1DM type 1 diabetes mellitus; Diabetes -- Periodicals; Diabetes Mellitus -- Periodicals; 616.462
• DOI: 10.1016/j.diabres.2022.109964
• Languages: English
• ISSNs: 0168-8227

Abstract

Highlights: Impaired awareness of hypoglycaemia (IAH) is a risk factor for severe hypoglycaemia in people with insulin-treated diabetes. Cardiovascular autonomic neuropathy has been associated with an increased risk for severe hypoglycaemia. In patients with IAH, better cardiovascular autonomic function was associated with increased time in hypoglycaemia and hypoglycaemic glucose variability. Patients with a higher percentage time spent in hypoglycaemic had a lower HbA1c and less microvascular complications. Autonomic neuropathy, does not seem to further deteriorate hypoglycaemic risk in patients with IAH. Abstract: Cardiovascular autonomic neuropathy (CAN) is suggested to underlie hypoglycaemic risk in impaired awareness of hypoglycaemia (IAH). We assessed the prevalence of CAN and the association between glucose variability (GV) and cardiovascular autonomic function in patients with type 1 diabetes (T1DM) and IAH. This study is a post-hoc-analysis of results obtained with the IN-CONTROL-trial, designed to assess the effects of continuous glucose monitoring (CGM) on glycaemia. Forty participants (aged 46.4 ± 11.4 years, diabetes duration 29.1 ± 13.5 years, HbA1c 7.5 ± 0.8%(58.2 ± 8.8 mmol/mol)) underwent 2-week blinded CGM measurements to obtain GV indices. Standardized cardiovascular reflex tests were used to determine the presence of CAN. Cardiovascular autonomic function was assessed with heart rate variability (HRV) measures. 14(35%) participants were classified as having CAN. Participants with CAN had lower percentage time spent in hypoglycaemic range and low blood glucose index(LBGI). After correction for confounders, a significant positive association was found between the coefficient of variation (CV) or time spent in hypoglycaemic range and HRV measures SDRR or RMSSD, and between LBGI and RMSSD. In patients with T1DM and IAH, hypoglycaemic parameters were associated with better cardiovascular autonomic function and lower prevalence of CAN. This suggests that autonomic neuropathy does not seem to further deteriorate hypoglycaemic risk in patients with IAH.