Heart rate variability in Parkinson’s disease – A time domain analysis

Abstract

Background: Cardiac autonomic dysfunction is an important non-motor feature of Parkinson’s disease and increase morbidity. Heart rate variability (HRV) is a noninvasive technique for assessment of cadiac sympathetic and parasympathetic tonic activity. Objective: To assess cardiac autonomic nerve function (CANF) in Parkinson’s disease by time domain analysis of HRV. Method: This analytical cross-sectional study was conducted in2023. For this, 30 newly diagnosed patients with Parkinson’s disease (age 45-70 years, male and female) and 30 apparently , matched healthy control were enrolled. To assess CANF, HRV was recorded from ECG based data acquisition device, Power lab 8/35, AD instruments, Australia. Time domain parameters were auto generated by Lab chart software. For statistical analysis unpaired “t” test was used by SPSS for windows version 16.  Results: Resting pulse rate was significantly higher in the Parkinson’s disease group than in controls ( p˂0.001).   In this study, mean heart rate was significantly higher(p<0.01) , standard deviation of the RR intervals (SDRR) (p˂0.001), standard deviation of the difference between successive RR intervals(SDSD), square root of mean squared difference of successive RR intervals (RMSSD), proportion of RR interval with duration ˃50 ms (pRR50% ) were significantly (p<0.001) lower in Parkinsons disease patients compared to healthy subjects. Conclusion: The present study concluded that impaired autonomic function characterized by reduced parasympathetic modulation may occur in Parkinson’s disease. J Bangladesh Soc Physiol 2026;21(1): 60-65