Paschoal MA1, Acorci GF1, Lamari N1
1Pontifical Catholic University of Campinas, Physical Therapy, Campinas, Brazil
Background: The cardiovascular system, like all organic systems, is subject to the regulatory action performed by the autonomic nervous system (ANS) to maintain the internal homeostasis. The literature shows that natural aging process and pre-adolescent obesity are factors that contribute to alter the cardiac autonomic modulation (CAM). However, individuals of these two groups were never compared in the same study using the active postural maneuver (APM) like stimuli to assessment the cardiovascular autonomic response.
Purpose: To compare the CAM during APM to know which factor (obesity in the pre-adolescence or the normal aging process) is more important to decrease the quality of CAM during the postural cardiovascular stress.
Methods: Were studied 10 sedentary obese pre-adolescent (OPA) aged 9 to 12 years old, which were included in the study according to the insertion of their body mass indices (BMI) in the values between the 95th and 97th percentiles of the National Center for Health Statistics (NCHS), and 10 normal and sedentary adults with age between 40 to 50yrs old, with BMI between 20-30 Kg/m2. All volunteers were submitted to a heart beats recording (RR intervals - RRi) with Polar RS800CX® monitor during 5min at rest in supine position in a room with controlled temperature (23°C). After, they performed a sudden active postural change to stand position and thus remained for another 5min. The data of rest and stand positions were analyzed by the linear method (time and frequency domain) of heart rate variability (HRV) with Polar Precision Performance software®. The two groups data were compared by the Kruskal-Wallis test and Dunn's Multiple comparison test, with the significance level established at p 0.05.
Results: The main results are:
a) the RRi that were not different between the groups at rest (supine position) became different at standing position (p 0.05) due to the important cardiovascular response showed by the OPA group (mean of 713.4ms to 580.0ms, respectively);
b) significant decrease of the cardiac parasympathetic indexes of HRV - pNN50 and RMSSD - showed only by the OPA group when standing (expected cardiovascular response when in standing), with the pNN50 mean value changing of 14.1% (supine) to 1.5% (standing) p 0.05; and RMSSD mean value changing of 61.4ms (supine) to 19.7ms (standing), also with p 0.05.
Conclusion(s): Although the two groups studied in this investigation frequently present modifications in CAM, we concluded that the natural aging process was more damaging to cardiac adjustments during the APM.
Implications: Abrupt changes in body position, especially supine to biped, should be controlled to avoid cardiovascular problems in older people.
Keywords: Obesity, aging, autonomic nervous system
Funding acknowledgements: No funding source.
Purpose: To compare the CAM during APM to know which factor (obesity in the pre-adolescence or the normal aging process) is more important to decrease the quality of CAM during the postural cardiovascular stress.
Methods: Were studied 10 sedentary obese pre-adolescent (OPA) aged 9 to 12 years old, which were included in the study according to the insertion of their body mass indices (BMI) in the values between the 95th and 97th percentiles of the National Center for Health Statistics (NCHS), and 10 normal and sedentary adults with age between 40 to 50yrs old, with BMI between 20-30 Kg/m2. All volunteers were submitted to a heart beats recording (RR intervals - RRi) with Polar RS800CX® monitor during 5min at rest in supine position in a room with controlled temperature (23°C). After, they performed a sudden active postural change to stand position and thus remained for another 5min. The data of rest and stand positions were analyzed by the linear method (time and frequency domain) of heart rate variability (HRV) with Polar Precision Performance software®. The two groups data were compared by the Kruskal-Wallis test and Dunn's Multiple comparison test, with the significance level established at p 0.05.
Results: The main results are:
a) the RRi that were not different between the groups at rest (supine position) became different at standing position (p 0.05) due to the important cardiovascular response showed by the OPA group (mean of 713.4ms to 580.0ms, respectively);
b) significant decrease of the cardiac parasympathetic indexes of HRV - pNN50 and RMSSD - showed only by the OPA group when standing (expected cardiovascular response when in standing), with the pNN50 mean value changing of 14.1% (supine) to 1.5% (standing) p 0.05; and RMSSD mean value changing of 61.4ms (supine) to 19.7ms (standing), also with p 0.05.
Conclusion(s): Although the two groups studied in this investigation frequently present modifications in CAM, we concluded that the natural aging process was more damaging to cardiac adjustments during the APM.
Implications: Abrupt changes in body position, especially supine to biped, should be controlled to avoid cardiovascular problems in older people.
Keywords: Obesity, aging, autonomic nervous system
Funding acknowledgements: No funding source.
Topic: Cardiorespiratory; Health promotion & wellbeing/healthy ageing
Ethics approval required: Yes
Institution: PUC - Campinas
Ethics committee: Comitê de Ética PUC Campinas
Ethics number: 1277837
All authors, affiliations and abstracts have been published as submitted.
