Spectral and symbolic analysis of the effect of gender and postural change on cardiac autonomic modulation in healthy elderly subjects

Autor(es)

Perseguini, N. M. ^[1] ; Takahashi, A. C. M. ^[1] ; Rebelatto, J. R. ^[1] ; Silva, E. ^{[1, 2]} ; Borghi-Silva, A. ^[1] ; Porta, A. ^[3] ; Montano, N. ^[4] ; Catai, A. M. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed Sao Carlos, Lab Fisioterapia Cardiovasc, NUPEF, Dept Fisioterapia, BR-13565905 Sao Carlos, SP - Brazil

^[2] Univ Metodista Piracicaba, Fac Ciencias Saude, Piracicaba, SP - Brazil

^[3] Univ Milan, Dept Technol Hlth, Galeazzi Orthopaed Inst, Milan - Italy

^[4] Univ Milan, Dept Clin Sci, L Sacco Hosp, Milan - Italy

• Tipo de documento: Artigo Científico
• Fonte: Brazilian Journal of Medical and Biological Research; v. 44, n. 1, p. 29-37, JAN 2011.
• Citações Web of Science: 20

Resumo

The objective of this study was to use linear and non-linear methods to investigate cardiac autonomic modulation in healthy elderly men and women in response to a postural change from the supine to the standing position. Fourteen men (66.1 +/- 3.5 years) and 10 women (65.3 +/- 3.3 years) were evaluated. Beat-to-beat heart rate was recorded in the supine and standing positions. Heart rate variability was studied by spectral analysis, including both low (LFnu-cardiac sympathetic modulation (CSM) indicator) and high (HFnu-cardiac vagal modulation (CVM) indicator) frequencies in normalized units as well as the low frequency/high frequency (LF/HF) ratio. Symbolic analysis was performed using the following indexes: 0V% (CSM indicator), 1V% (CSM and CVM indicators), 2LV% (predominantly CVM indicator) and 2ULV% (CVM indicator). Shannon entropy was also calculated. Men presented higher LFnu and LF/HF ratio and lower HFnu and 1V% symbolic index (57.56, 4.14, 40.53, 45.96, respectively) than women (24.60, 0.45, 72.47, 52.69, respectively) in the supine position. Shannon entropy was higher among men (3.53) than among women (3.33) in the standing position, and also increased according to postural change in men (3.25; 3.53). During postural change, the LFnu (24.60; 49.85) and LF/HF ratio (0.45; 1.72) increased, with a concomitant decrease in HFnu (72.47; 47.56) and 2LV% (14.10; 6.95) in women. Women presented increased CSM in response to postural change and had higher CVM and lower CSM than men in the supine position. In conclusion, women in the age range studied presented a more appropriate response to a postural change than men, suggesting that cardiac autonomic modulation may be better preserved in women than in men. (AU)

• Processo FAPESP: 06/52860-0 - Efeito do treinamento de forca excentrica na modulacao da frequencia cardiaca e nas respostas da eletromiografia durante contracoes isometricas.
• Beneficiário: Anielle Cristhine de Medeiros Takahashi
• Modalidade de apoio: Bolsas no Brasil - Doutorado
• Processo FAPESP: 05/54838-9 - Avaliação cardiorrespiratória e da variabilidade da frequência cardíaca de pacientes submetidos à intervenção fisioterapêutica: fases I e II da reabilitação cardiovascular
• Beneficiário: Aparecida Maria Catai
• Modalidade de apoio: Auxílio à Pesquisa - Regular