Socioeconomic status, age and heart rate variability in a Bangladeshi community

Socioeconomic status (SES) is a risk factor for cardiovascular disease (CVD) and either low or high heart rate variability (HRV) at rest has been shown to predict cardiovascular morbidity and mortality. The study investigated the extent HRV features can predict SES. Four hundred and twenty eight people were randomly selected from the commercial districts (high SES) and slum areas (low SES) within Dhaka city. Demographic, clinical, and HRV features were recorded. Of the clinical variables age, waist circumference and diastolic blood pressure (p<0.01) were significantly different. HRV feature extraction from heart rate recordings were analyzed using Kubios software. Age corrected results showed that high frequency power (Median (IQR): 112.1 (85.6) ms² vs. 96.8 (97.6) ms², p=0.02) and the correlation dimension (0.78 (0.82) vs. 0.51 (1.20), p<0.0002) were significantly lower in the low SES group, whilst the high frequency peak was significantly higher (0.1500 (0.0004) Hz vs. 0.1503 (0.0066) Hz, p<0.0001). Our results show that although the high SES group had a more sedentary behavior, the low SES group had a higher risk of cardiac arrhythmia even though they were generally younger with normal blood pressure and waist circumference.