Lower Cardiac Vagal Tone in Non-Obese Healthy Men with Unfavorable Anthropometric Characteristics

Abstract

OBJECTIVES:to determine if there are differences in cardiac vagal tone values in non-obese healthy, adult men with and without unfavorable anthropometric characteristics.INTRODUCTION:It is well established that obesity reduces cardiac vagal tone. However, it remains unknown if decreases in cardiac vagal tone can be observed early in non-obese healthy, adult men presenting unfavorable anthropometric characteristics.METHODS:Among 1688 individuals assessed between 2004 and 2008, we selected 118 non-obese (BMI <30 kg/m2), healthy men (no known disease conditions or regular use of relevant medications), aged between 20 and 77 years old (42 ± 12-years-old). Their evaluation included clinical examination, anthropometric assessment (body height and weight, sum of six skinfolds, waist circumference and somatotype), a 4-second exercise test to estimate cardiac vagal tone and a maximal cardiopulmonary exercise test to exclude individuals with myocardial ischemia. The same physician performed all procedures.RESULTS:A lower cardiac vagal tone was found for the individuals in the higher quintiles – unfavorable anthropometric characteristics - of BMI (p=0.005), sum of six skinfolds (p=0.037) and waist circumference (p<0.001). In addition, the more endomorphic individuals also presented a lower cardiac vagal tone (p=0.023), while an ectomorphic build was related to higher cardiac vagal tone values as estimated by the 4-second exercise test (r=0.23; p=0.017).CONCLUSIONS:Non-obese and healthy adult men with unfavorable anthropometric characteristics tend to present lower cardiac vagal tone levels. Early identification of this trend by simple protocols that are non-invasive and risk-free, using select anthropometric characteristics, may be clinically useful in a global strategy to prevent cardiovascular disease.

Heart Rate Variability in Shift Workers: Responses to Orthostatism and Relationships with Anthropometry, Body Composition, and Blood Pressure

“…Similar results were reported by Ramos and Araújo [30], who found that cardiac vagal components decrease in parallel with increases in BMI, the sum of skinfold measurements (reflecting total body fat), and WC. Additionally, other studies found a relationship between WC, BF, and WHR and HRV vagal components [5, 26, 31].…”

Cardiac vagal withdrawal and reactivation during repeated rest–exercise transitions

“…Considering that at onset of exercise and recovery from exercise there is a fast HR change largely mediated by the vagal branch, both the CVW and the CVR have been used to identify vagal modulation impairments related to diseases (Leeper et al 2007;Ramos and Araújo 2010;Ricardo et al 2005). In addition, it has been shown that the CVW and CVR are associated (Leeper et al 2007;Ricardo et al 2005), and that both can be used for prognostic purposes (Leeper et al 2007).…”

Original research articles on the cardiopulmonary system recently appeared in Brazilian clinical and surgical journals

“…The Neural Control of cardiac vagal tone in non-obese healthy men with unfavorable anthropometric characteristics showed that this population tends to present lower cardiac vagal tone levels. Early identification of this trend by simple protocols that are non-invasive and risk-free, using select anthropometric characteristics, may be clinically useful in a global strategy to prevent cardiovascular disease 68 .…”