Evidence Hub

546-P: Effects of Metformin on Heart Rate Variability in Adolescents with Type 1 Diabetes: A Secondary Analysis of a Randomized Crossover-Controlled Trial

Dai-Zhi Yang, Wen Xu, Hong-Rong Deng, Jing Lv, Jin-Hua Yan, B. Yao, J. Weng

2020

1 citation

Abstract

Aims: Metformin might improve glycemic control in patients with T1D, but whether it has cardiovascular benefit is controversial. We aimed to investigate whether metformin improved cardiac autonomic neuropathy, as measured by heart rate variability (HRV), in patients with T1D. Methods: This is a secondary analysis of a crossover, randomized trial conducted in adolescents with T1D inadequately controlled with insulin. Patients were randomly received metformin added on insulin for 24 weeks followed by insulin treatment alone for a subsequent 24 weeks or vice versa. The mean amplitude of glycemic excursions (MAGE) was obtained from CGM as a measure of glucose variability, while SD of beat-to-beat (NN) intervals (SDNN), SD of the average NN intervals calculated over 5 minutes (SDANN), the percentage of the interval differences of successive NN intervals greater than 50 ms (PNN50), the square root of the mean squared differences of successive NN intervals (RMSSD), low-frequency (LF) and high frequency (HF) power were assessed by 24-h Holter monitoring as measures of HRV. Results: Seventeen patients with age 14.4±2.3 years, BMI 18.2±1.8 kg/m2, T1D duration 5.4±3.2 years and HbA1c 9.2±1.6% were enrolled. Changes in HbA1c, BMI, lipid profiles and MAGE were similar between groups. Compared with insulin monotherapy, metformin added on insulin markedly increased SDNN (between group difference [SE], 26.96 [11.77], P=0.034), SDANN (25.62 [12.12], P= 0.049), pNN50 (10.14 [3.05], P= 0.003)…

How strong is the evidence?

Evidence Hub reads this as a secondary / pooled analysis, done in people. Its evidence level is 3 of 5 (Moderate · trial / cohort / secondary analysis). Trials without a large randomized design, cohorts and secondary analyses give moderate evidence.

How the five levels of evidence work. The level is assigned automatically from the abstract and can be wrong, so check the paper.

Read the paper

Related studies

Go deeper in Evidence Hub

Evidence Hub adds a study data sheet (design, sample size, evidence level, key numbers), an AI summary and a chat grounded in the paper's text.

Open this study Sign up free