Cardiac autonomic nervous dysfunction detected by both heart rate variability and heart rate turbulence in prediabetic patients with isolated impaired fasting glucose

Abstract

Objective:Cardiac autonomic nervous dysfunction (CAND), a severe complication of diabetes, has also been shown to affect prediabetic patients. The role of isolated impaired fasting plasma glucose (IFG), a subtype of prediabetes, is not clear in the pathogenesis of CAND. The aim of this study was to examine the relationship between isolated IFG and cardiac autonomic function using heart rate variability (HRV) and heart rate turbulence (HRT) indices derived from 24-h Holter–electrocardiogram recordings.Methods:This observational, prospective, cross-sectional study examined 400 consecutive subjects divided into three groups according to oral glucose tolerance test results: the control group [Group I, fasting plasma glucose (FPG) <100 mg/dL and normal glucose tolerance, n=193], the isolated IFG group (Group II, FPG ≥100 and <126 mg/dL, n=134), and the isolated impaired glucose tolerance (IGT), both IFG and IGT, or newly diagnosed diabetes’ group (Group III, n=73). Patients with non-sinus rhythm, known diabetes mellitus, coronary artery disease, heart failure, severe valvular disease, or receiving medical therapy that may affect HRV and HRT indices were excluded. Time domain HRV parameters, turbulence onset (TO), turbulence slope (TS), and HRT category were examined. Chi-square, one-way analysis of variance, Kruskal–Wallis H, and Mann–Whitney U tests were used to compare variables where appropriate. The correlation between Holter data and FPG levels was analyzed using the Spearman’s test. Multiple linear regression analysis was performed to identify independent predictors of the HRV and HRT parameters.Results:Median (interquartile range 25–75) FPG levels in Groups I, II, and III were 89 (83/93) mg/dL, 109 (104/116) mg/dL, and 174 (150.5/197) mg/dL, respectively. There were significant differences in HRV and HRT parameters between and among all groups. While HRV parameters and TS decreased from Group I to Group III, TO and HRT category gradually increased. Additionally, FPG level was significantly correlated with SDNN, r=–0.220; SDNN index, r=–0.192; SDANN, r=–0.207; RMSSD, r=–0.228; pNN50, r=–0.226; TO, r=0.354; and TS, r=–0.331 (all p<0.001).Conclusion:CAND, as detected by both HRV and HRT, appear to be present in the isolated IFG subtype of prediabetes.

Novel results and future perspectives of study of cardiovascular autonomic control in prediabetic patients

“…Synchronization of low-frequency oscillations may be useful in cardiac event risk stratification ( 11 ) and control of therapeutic treatment ( 12 ) in patients with hypertension and MI. Further research regarding the interaction between slow oscillations in HRV and PPGV among prediabetic patients may complete and expand the results of Dr. Balcıoğlu et al ( 7 ).…”

“…Balcıoğlu et al ( 7 ) demonstrated the association between prediabetic condition (isolated fasting hyperglycemia) and CAND in an article in the current issue of the Anatolian Journal of Cardiology entitled “Cardiac autonomic nervous dysfunction detected by both heart rate variability and heart rate turbulence in prediabetic patients with isolated impaired fasting glucose.” HRT abnormality, considered an autonomic imbalance, was found in prediabetic patients. According to Balcıoğlu et al ( 7 ) and some other researchers ( 8 , 9 ), damage to neurofibers responsible for regulating cardiac and vascular function under hyperglycemia is one reason for CAND in diabetic patients. This statement is supported by the association between isolated fasting hyperglycemia and all evaluated parameters of autonomic cardiac regulation.…”

“…We would also like to emphasize that HRV and HRT are quite useful for anatomic cardiac regulation, but not the regulation of peripheral blood flow. Further research in the field, suggested by Dr. Balcıoğlu et al ( 7 ), may create a new research subject “autonomic function of cardiovascular system” instead of “autonomic function of the heart” in prediabetic patients. The synchronization of low-frequency oscillations in HRV and photoplethysmographic waveform variability (PPGV) reflects the functional interaction between the heart and peripheral circulation by means of autonomic regulation mechanisms ( 10 ).…”

IGRNet: A Deep Learning Model for Non-Invasive, Real-Time Diagnosis of Prediabetes through Electrocardiograms

“…It must be emphasized that the current study highlights a certain difference between prediabetic and normal people in ECGs; however, this difference is usually ignored in clinical practice. Among them, Balcıoğlu et al found that IGR patients exhibited different degrees of CAND, by recording the heart rate variability and heart rate turbulence indexes of 24-h dynamic ECGs [ 42 ]. Yu et al adopted dual-source computed tomography to evaluate the relationship between coronary atherosclerosis (CAA) and blood glucose levels; they found that the prevalence of CAA in the prediabetic group was slightly higher than that of the normoglycemic group but lower than that of the diabetic group, which indicates that prediabetic patients have an increased risk of CAA.…”

Análisis de la variabilidad de la frecuencia cardíaca en mujeres embarazadas de primer trimestre tratadas con metformina

“…En el embarazo producto del estrés metabólico la intolerancia a los carbohidratos también suele ser una afección temporal [4]. En estas patologías existe una alteración de la VFC con un predominio simpático considerado como un signo de alteración en el sistema nervioso autónomo (SNA) [5].…”