EFFECTS OF OBESITY, CURRENT SMOKING STATUS, AND ALCOHOL-CONSUMPTION ON HEART-RATE-VARIABILITY IN MALE WHITE-COLLAR WORKERS

In order to examine the effects of mild to moderate obesity, moderate to heavy smoking, and moderate alcohol consumption on cardiac parasymp athetic activities and systemic sympathetic activities, a cross-sectio nal survey was carried out in 282 healthy Japanese male white-collar w orkers. Their autonomic activities were assessed as amplitudes of spec tral components of heart rate variability (HRV) which was measured in the annual physical examination at their work sites. Taking the effect s of aging on HRV into account, the cardiac parasympathetic activity a t supine rest and its response to a change in posture were reduced in mildly to moderately obese subjects with a body mass index of 21-36, w hereas the sympathetic activity was not. The effects of smoking and al cohol consumption on HRV were not confirmed. The above results means t hat we should consider obesity as a covariate when we examine possible relationships between cardiac parasympathetic activity and other envi ronmental factors, There isa need for further studies on the relations hips among obesity, change in parasympathetic activity, and developmen t of health problems, The dose-effect relationships between long-term smoking or alcohol consumption and chronic changes in autonomic activi ties also remain to be determined.