A pilot study on short term heart rate variability & its correlation with disease activity in Indian patients with rheumatoid arthritis.

Background & objectives: Cardiovascular complications may lead to mortality in patients with rheumatoid arthritis (RA). We assessed heart rate variability (HRV), an important autonomic function, to quantify the risk for cardiovascular complications in Indian patients with RA. Methods: The study was carried out in RA patients (n=45) diagnosed as per American College of Rheumatology criteria and healthy controls. HRV recording and analysis was done using Nevrokard software using time and frequency domain analyses. The overall autonomic tone, parasympathetic drive, sympathetic drive and sympatho-vagal ratio were quantified by using various parameters. It included standard deviation of all R-R intervals (SDNN), standard deviation of successive differences between adjoining normal cycles (SDSD), root-mean square of successive differences (RMSSD), and number of R-R intervals differing by >50 ms from adjacent intervals (NN50) in the time domain analysis. In frequency domain analysis, low frequency (LF) and high frequency (HF), LF/HF and total power were assessed. Results: Demographic profile was comparable between groups; however, systolic BP was higher in patients with RA. SDNN, SDSD, RMSSD, NN50, LF and HF power and total power (ms × ms) were significantly lower in patients with RA versus healthy controls (P<0.001). Disease activity score at 28 joints indicating severity of the disease was significantly and positively correlated with SDSD (r=0.375, R2=14.06; P=0.045) while LF and HF power (ms × ms) were significantly and inversely correlated with rheumatoid factor (r=-0.438 and -0.445; R2=19.1 and 19.8; P=0.017 and 0.016, respectively). Interpretation & conclusions: HRV was significantly altered in patients with RA and independently associated with disease activity. Hence autonomic function testing, using HRV, may be useful as part of cardiovascular risk assessment in these patients.

effect of fasting in Ramadan on patients with heart disease.

To determine the clinical and biochemical effects of fasting during Ramadan on patients with cardiac disease. Eighty-six outpatients with heart disease with intention to fast were studied in the month of Ramadan 1996 [1416 H] at the King Fahd Armed Forces Hospital, Jeddah, Kingdom of Saudi Arabia. Detailed clinical and biochemical assessments were performed within 3 days before the start of Ramadan and then on the last day of Ramadan. There were 54 [62.8%] males and 32 [37.2%] females with a mean age of 56.3 years [range, 17-84]. Forty-six patients [53%] had coronary artery disease, 23 patients [27%] had valvular heart disease, 13 patients [15%] had congestive heart failure and 4 patients [5%] were treated for arrhythmia. Sixty-two patients [72%] were in New York Heart Association [NYHA] Class I, 18 patients [21%] in Class II, and 6 patients [7%] were in Class III. Seventy-four patients [86%] managed to fast during the entire Ramadan, 9 patients [10.4%] missed the fasting for up to 7 days, and 3 patients [3.5%] could not fast. There were no significant changes in the NYHA Class [p=0.12]. No significant changes occurred in any of the hematological or biochemical parameters during the fasting of Ramadan. The effects of fasting during Ramadan on stable patients with cardiac disease are minimal. The majority of patients with stable cardiac disease can fast during Ramadan without significant detrimental effects