Year : 2026

Volume : Volume 17

Issue : Issue 1

Address for correspondence :
Dr. Thakur Shailesh Kumar Singh
shaileshkumarphysio@gmail.com

Abstract

Background: Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease characterized by synovial inflammation and joint damage. Beyond the joints, RA is associated with significant extra-articular manifestations, including cardiovascular autonomic dysfunction. Heart rate variability (HRV) is a simple, non-invasive, and reliable tool for the assessment of autonomic nervous system function. Most previous studies have focused on patients with established RA, often confounded by long disease duration and medication effects. Materials and Methods: A case–control study was conducted involving 42 newly diagnosed (duration <6 months), treatment-naïve RA patients (mean age 45.2 ± 8.1 years; 33 females, 9 males) and 42 healthy controls (mean age 44.8 ± 7.9 years; 33 females, 9 males). A standard 5-min resting electrocardiogram was recorded for all participants. HRV analysis was performed to derive time-domain parameters: Standard deviation of NN intervals (SDNN), root mean square of successive differences (RMSSD), and frequency-domain parameters: Low frequency (LF) power, high frequency (HF) power, and LF/HF ratio. Results: The RA group showed a significant reduction in all HRV parameters compared to the control group. SDNN (32.1 ± 8.4 ms vs. 48.9 ± 11.2 ms, P < 0.001), RMSSD (21.5 ± 6.8 ms vs. 35.3 ± 9.7 ms, P < 0.001), and total power (346 ± 112 ms2 vs. 782 ± 245 ms2 , P < 0.001) were markedly lower in the RA group. In the frequency domain, both LF power (112 ± 45 ms2 vs. 285 ± 98 ms2 , P < 0.001) and HF power (98 ± 41 ms2 vs. 254 ± 87 ms2 , P < 0.001) were significantly reduced. The LF/HF ratio was not significantly different between the two groups (1.18 ± 0.4 vs. 1.12 ± 0.3, P = 0.45). Conclusion: Newly diagnosed, treatment-naïve RA patients exhibit significantly reduced HRV, indicating global autonomic impairment affecting both sympathetic and parasympathetic branches equally, without a shift in autonomic balance. This suggests that autonomic dysfunction is an early feature of RA, possibly linked to the systemic inflammatory process itself. HRV serves as a valuable tool for its early detection.