Significant abnormal glycemic variability increased the risk for arrhythmias in elderly type 2 diabetic patients

Abstract

Background Little is known about whether the influence of glycemic variability on arrhythmia is related to age in type 2 diabetes mellitus (T2DM). Therefore, we aimed to compare the association between glycemic variability and arrhythmia in middle-aged and elderly T2DM patients. Methods A total of 107 patients were divided into two groups: elderly diabetes mellitus group (EDM, n = 73) and middle-aged diabetes mellitus group (MDM, n = 34). The main clinical data, continuous glucose monitoring (CGM) and dynamic ECG reports were collected. The parameters including standard deviation of blood glucose (SDBG), largest amplitude of glycemic excursions (LAGE), mean amplitude of glycemic excursions (MAGE), absolute means of daily differences (MODD), time in range (TIR), time below range (TBR), time above range (TAR), coefficient of variation (CV) were tested for glycemic variability evaluation. Results In terms of blood glucose fluctuations, MAGE (5.77 ± 2.16 mmol/L vs 4.63 ± 1.89 mmol/L, P = 0.026), SDBG (2.39 ± 1.00 mmol/L vs 2.00 ± 0.82 mmol/L, P = 0.048), LAGE (9.53 ± 3.37 mmol/L vs 7.84 ± 2.64 mmol/L, P = 0.011) was significantly higher in EDM group than those of MDM group. The incidences of atrial premature beat, couplets of atrial premature beat, atrial tachycardia and ventricular premature beat were significantly higher in EDM group compared with the MDM group (all P < 0.05). Among patients with hypoglycemia events, the incidences of atrial premature beat, couplets of atrial premature beat, atrial tachycardia and ventricular premature beat (all P < 0.05) were significantly higher in the EDM group than those in the MDM group. In EDM group, TIR was negatively correlated with atrial tachycardia in the MAGE1 layer and with atrial tachycardia and ventricular premature beat in the MAGE2 layer, TBR was significantly positively correlated with atrial tachycardia in the MAGE2 layer (all P < 0.05). In MDM group, TAR was positively correlated with ventricular premature beat and atrial tachycardia in the MAGE2 layer (all P < 0.05). Conclusions The study demonstrated the elderly patients had greater glycemic variability and were more prone to arrhythmias. Therefore, active control of blood glucose fluctuation in elderly patients will help to reduce the risk of severe arrhythmia.

Celebrities in the heart, strangers in the pancreatic beta cell: Voltage‐gated potassium channels Kv7.1 and Kv11.1 bridge long QT syndrome with hyperinsulinaemia as well as type 2 diabetes

“…In accordance with this, glycaemic control in the form of daily insulin injections has been shown to shorten QTc in patients with T2DM. 162 Increased QTc has also been reported in patients with type 1 diabetes 163,164 , and glycaemic variability alone has been shown to increase the incidence of cardiac arrhythmia in individuals with T2DM, 165 further supporting that long-term hyperglycaemia may affect cardiac electrophysiology as well.…”

A meta‐analysis of the relationship between glycaemic variability and the mortality of patients with heart failure

“…40 On the other hand, clinical studies have shown that a high GV is associated with prolonged QTc duration and QTc dispersion, 41 as well as an elevated risk of arrhythmia in individuals with diabetes. 42,43 This implies that a high fluctuation in glucose levels may also pose a risk of arrhythmia in patients with HF. In fact, a preliminary investigation indicated that a significant 24-h fluctuation in blood glucose levels was linked to an increase in ventricular ectopic activity in patients with HF and concomitant diabetes.…”

“…Moreover, a recent investigation indicated that variations in glucose levels may induce apoptosis in cardiomyocytes by activating the signalling pathway of endoplasmic reticulum stress in rats with diabetes and in primary cardiomyocytes 40 . On the other hand, clinical studies have shown that a high GV is associated with prolonged QTc duration and QTc dispersion, 41 as well as an elevated risk of arrhythmia in individuals with diabetes 42,43 . This implies that a high fluctuation in glucose levels may also pose a risk of arrhythmia in patients with HF.…”

Effects of Glucose Fluctuations on Electrocardiogram Readings and the Development of Ventricular Arrhythmia in Diabetic Rats

“…Clinical trials have demonstrated that diabetic patients have more ECG abnormalities and a higher incidence of ventricular arrhythmias compared with normal individuals. [23][24][25] Recent studies have demonstrated that GF are more harmful to patients with DM than sustained hyperglycemia. However, the relationship between GF and lethal ventricular arrhythmias, such as VT or VF, remains elusive.…”