Cardiac autonomic impairment and low serum vitamin B12 and high homocysteine level in Parkinson’s disease -Frequency domain analysis ofheartratevariability

Background: Parkinson’s disease (PD)adversely affects autonomic control as well as alteration of serum vitamin B12 and homocysteine level. Heart rate variability (HRV) is a reliablemethod for assessing autonomic function.Objective:To investigate the role of serum vitamin B12 and homocysteine level for cardiac autonomic impairmennt by analyzing frequency domain measures of HRV in male patients with PD. Methods: This observational analytical crosssectional study was involved 30 newly diagnosed male PD patients of 50-60 years age visiting the Out Patient Department of Neurology, Bangabandhu Sheikh MujibMedical University (BSMMU), Dhaka. Thirty age and BMI matched apparently healthy male subjects were included as control. Serum vitamin B12 and homocysteine were determined by chemiluminescent immunoassay method and HRV were measured by using a data acquisition device, Powerlab 8/ 35, AD instruments with labchart software analysis.. Independent sample t-test and Pearson’s correlation coefficient test were used for statistical analysis. Results: In this study, resting pulse rate,low frequency power in normalized unit (LF norm), ratio of low frequency and high frequency power (LF/ HF) were found significantly higher (p<0.001) and total power (TP), low frequency power (LF power),high frequency power (HF power), HF power in normalized unit (HF norm), were found significantly lower (p<0.001) in PD patients compared to control. In addition, serum vitamin B12 level was found significantly lower (p<0.01) and homocysteine level was found significantly higher (p<0.001) in PD patients than that of control. On correlation analysis,serum vitamin B12 was significantly negatively correlated with LF/HF (p<0.05). Besides, serum homocysteine was significantly negatively correlated with HF power(p<0.01), HF norm (p<0.001) and significantly positively correlated with LF norm (p<0.001), LF/HF (p<0.001). Conclusion:Low serum vitamin B12 and high serum homocysteine level are associated with reduced HRV in male patients with PD. J Bangladesh Soc Physiol 2024;19(2): 46-54