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

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 percent (CSM indicator), 1V percent (CSM and CVM indicators), 2LV percent (predominantly CVM indicator) and 2ULV percent (CVM indicator). Shannon entropy was also calculated. Men presented higher LFnu and LF/HF ratio and lower HFnu and 1V percent 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 percent (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.

Posición oficial de la Sociedad Chilena de climaterio para el manejo de la mujer climatérica / Official position of the Chilean Society of menopause for the management of climacteric women

La mayoría de las mujeres ve afectada su salud en el período climatérico, ya sea por sintomatología que le deteriora su calidad de vida (CV) o por la aparición de enfermedades crónicas que le afectan sus expectativas de vida. Por lo tanto, es básico evaluar estos dos aspectos, teniendo como objetivos centrales de las eventuales intervenciones terapéuticas, mejorar la CV y reducir el riesgo de enfermedades cardiovasculares y/o fracturas...