Abstract:
Background: Cardiovascular Autonomic Diabetic Neuropathy
(CADN) is one of the most important diabetes- associated
complications. Reduced heart rate variation (HRV) is the
earliest indicator of CADN. The prospect of using time domain
analysis of HRV using mental arithmetic as a stressor has for
early diagnosis of CADN has not been studied so far.
Aims & Objective: To compare time domain parameters of
HRV at rest and during acute mental stress between Type 2
diabetics and non- diabetics.
Materials and Methods: 30 male asymptomatic, Type 2
diabetics with duration of diabetes of 2-8 yrs with RBS ≥ 200
mg/dl or FBS ≥ 126 mg/dl in the age group of 30-65 yrs were
chosen as subjects. 30 age and sex matched healthy non-
diabetics were chosen as controls. HRV analysis was done using
ECG recorded at rest in supine position for 5 min and during 5
min of acute mental stress testing.
Results: At rest standard deviation of all R-R intervals (SDNN),
root mean square of successive RR- interval differences
(RMSSD), number of intervals differing by > 50ms from
adjacent interval (NN50) and percentage of NN50 (pNN50)
were significantly less in diabetics as compared to non-
diabetics. Mental stress showed increases in HR, SBP and DBP
in non-diabetics as well as diabetics but SDNN was significantly
less in diabetics as compared to non- diabetics during stress.
Conclusion: Data from the study demonstrated that diabetics
with 8-10 yrs history had already developed parasympathetic
autonomic neuropathy. Time domain analysis of HRV during
mental stress can be used as a valuable tool for early diagnosis
of autonomic neuropathy to prevent further complications.
