Short term heart rate variability for early assessment of autonomic neuropathy in patients with type 2 diabetes mellitus: A comparative cross-sectional study

Abstract

A B S T R A C TBackground: Cardiovascular autonomic diabetic neuropathy (CADN) is an important diabetes-associated complication. Reduced heart rate variation is the earliest indicator of CADN. Aims: The aim was to study the prospect of using short term heart rate variability (HRV) analysis for early diagnosis of CADN. Settings and Design: The type of this study was hospital-based comparative cross-sectional study. Materials and Methods: A total of 30 asymptomatic, type 2 diabetic male patients with duration of diabetes of 1-5 years with random blood sugar ≥200 mg/dl (11.1 mmol/L) or fasting blood sugar ≥126 mg/dl (7 mmol/L) in the age group of 30-65 years were selected as subjects. Thirty age and sex matched healthy nondiabetics were selected as controls. HRV analysis was performed using electrocardiogram recorded in lead II, at rest, in the supine position for 5 min. Results: Total power, low frequency power, high frequency power, standard deviation of all R-R intervals, root mean square of successive RR-interval differences, number of intervals differing by >50 ms from adjacent interval (NN50), and percentage of NN50 (pNN50) were signifi cantly less in diabetics when compared to nondiabetics (P < 0.05). Conclusion: Data from the study demonstrated that asymptomatic diabetics with <5 years history had already developed autonomic neuropathy. Short term analysis of HRV can be used as a valuable tool for early diagnosis of autonomic neuropathy.

Effect of supine rest on cardiac autonomic tone in type 2 diabetes mellitus

“…Similar results were reported by other studies. 17,[24][25][26][27][28] These results of this study did not observe any expected significant changes about autonomic status when compared between patients and control even after performing SR by the patients.…”

Diabetic Cardiac Autonomic Dysfunction and Its Relationship with Duration of Diabetes

“…Reduced HRV is the earliest sign of CAN 2,[5][6][7][8] . Decline in HRV in T2DM was seen in several studies 3,[9][10][11][12] . Despite the unclear nature of association between the duration of diabetes and autonomic dysfunction 13 , many studies observed the existence of relationship between these two 3,7,9,[14][15] .…”

Evaluation of Autonomic Dysfunction by Heart Rate Variability Analysis in Type 2 Diabetes Mellitus

“…Nevertheless, these tests only detect symptomatic or clinical CAN [4,8] which may not be sensitive enough to detect subtle abnormalities in cardiac autonomic nerve activity [9].…”

“…Recently, reduced HRV has been recognized as the earliest sign of CAN [9,11,[13][14][15][16][17]. 5 minutes HRV test, such as 24 hrs HRV measurement, is a reliable, convenient, and economically practicable technique for detecting autonomic dysfunction [4,[9][10]18].…”

“…5 minutes HRV test, such as 24 hrs HRV measurement, is a reliable, convenient, and economically practicable technique for detecting autonomic dysfunction [4,[9][10]18]. Moreover, only a few studies have been conducted on T2DM patients through 5 minutes HRV analysis to explore the resting autonomic tone.…”