Volume 10 Issue 2
Effect of the Postural Challenge on the Dependence of the Cardiovascular Control Complexity on Age
Oliver Faugeras and James MacLaurinby Aparecida M. Catai, Anielle C.M. Takahashi, Natália M. Perseguini, Juliana C. Milan, Vinicius Minatel, Patrícia Rehder-Santos, Andrea Marchi, Vlasta Bari and Alberto Porta
1Cardiovascular Physiotherapy Laboratory, Nucleus of Research in Physical Exercise, Department of Physiotherapy, Federal University of São Carlos, Rodovia Washington Luís, km 235, Monjolinho, 13565-905 São Carlos, SP, Brazil
2Research Laboratory on Healthy Aging, Department of Physiotherapy, Federal University of São Carlos, Rodovia Washington Luís, km 235, Monjolinho, 13565-905 São Carlos, SP, Brazil
3Department of Anesthesia and Intensive Care Unit, Humanitas Clinical and Research Center, Via Manzoni 56, 20089 Rozzano, Italy
4Department of Cardiothoracic, Vascular Anesthesia and Intensive Care, IRCCS Policlinico San Donato, Via Morandi 30, 20097 San Donato Milanese, Milan, Italy
5Department of Biomedical Sciences for Health, University of Milan, Via R. Galeazzi 4, 20161 Milan, Italy
6IRCCS Galeazzi Orthopedic Institute, Via R. Galeazzi 4, 20161 Milan, Italy
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Author to whom correspondence should be addressed.
Abstract
Short-term complexity of heart period (HP) and systolic arterial pressure (SAP) was computed to detect age and gender influences over cardiovascular control in resting supine condition (REST) and during standing (STAND). Healthy subjects (n = 110, men = 55) were equally divided into five groups (21–30; 31–40; 41–50; 51–60; and 61–70 years of age). HP and SAP series were recorded for 15 min at REST and during STAND. A normalized complexity index (NCI) based on conditional entropy was assessed. At REST we found that both NCIHP and NCISAP decreased with age in the overall population, but only women were responsible for this trend. During STAND we observed that both NCIHP and NCISAP were unrelated to age in the overall population, even when divided by gender. When the variation of NCI in response to STAND (ΔNCI = NCI at REST-NCI during STAND) was computed individually, we found that ΔNCIHP progressively decreased with age in the overall population, and women were again responsible for this trend. Conversely, ΔNCISAP was unrelated to age and gender. This study stresses that the complexity of cardiovascular control and its ability to respond to stressors are more importantly lost with age in women than in men.
Keywords:aging; gender; standing; heart rate variability; blood pressure variability; complexity; corrected conditional entropy; autonomic nervous system