Assessment of heart rate variability in participants with chronic obstructive pulmonary disease

Background: Chronic obstructive pulmonary disease (COPD) is one of the main causes of morbidity and mortality worldwide. COPD kills half a million people in India every year, more than those who die due to tuberculosis, malaria, or Acquired immune deficiency syndrome, and 30 million people suffer with COPD in India.[1] The hypoxemia due to COPD might be associated with autonomic dysfunction which could be evaluated with heart rate variability (HRV). Aims and Objective: To determine the HRV in patients with COPD and to compare with normal individuals. Materials and Methods: This cross-sectional study was carried out in 30 COPD patients attending the Department of Pulmonology, SRM Medical College Hospital and Research Centre and 30 age and sex-matched healthy individuals as a control group. A detailed history from the participants, such as weight and height, was obtained, and HRV parameters such as mean RR, mean HR, successive normal sinus RR intervals >50 ms (NN50), the percentage of successive normal sinus RR intervals >50 ms (pNN50), root mean square of successive heartbeat interval differences (rMSSDs), high frequency (HF), low frequency (LF), and LF/HF were estimated using physio-pac instrument. Results: HRV parameters such as rMSSD, NN50, PNN50, LF, HF, and LF/HF ratio show significant differences between the COPD and control (P < 0.05), which indicates sympathovagal imbalance. Conclusion: HRV analysis shows that COPD participants have an autonomic imbalance suggestive of an increased sympathetic tone or decreased parasympathetic tone. Sympathetic overactivity may lead to cardiovascular disease development in patients with COPD. [Natl J Physiol Pharm Pharmacol 2017; 7(1.000): 85-89]