Oxidative stress biomarkers and complexity of heart rate variability during acute single cigarette smoking

Smoking causes sympathovagal changes and peripheral vessel injury, which can be assessed by heart rate variability (HRV) that includes endothelial nitric oxide (NO) and sLOX-1 markers, respectively. This study aimed to investigate the HRV and NO changes in acute smoking and sLOX-1 overproduction in chronic smoking. A total of 60 males were recruited. Thirty smokers and 30 non-smokers were studied. At first the HRV parameters were obtained from all subjects. Only smokers were then consecutively recorded for 5 min and 15 min after smoking a single cigarette with simultaneous blood collection at each time point for NO and sLOX-1 measurements. We found a significant lowering of HRV and a positive correlation between sLOX-1 and mean arterial pressure in smokers. After 5 min of smoking, an immediate adverse effect of autonomic function was represented by the HRV along with an immediate lowering of NO which is a vasodilator. Acute smoking influences the autonomic neural control from NO-mediated modulation which can be assessed by the noninvasive technique of HRV analysis.