Correlação entre grau de comprometimento do sistema nervoso autônomo e índices de qualidade de vida na percepção de um grupo de idosos

Abstract

In the last decades with the increasing number of elderly population, investigations on the quality of life during the aging process have been required. Heart Rate Variability (HRV) evaluates the modulation of the Autonomic Nervous System (ANS) and indicates the ability of the heart to respond to multiple physiological and environmental stimuli as well as diseases. Objective: To investigate the perception of the quality of life of older elderlies. and its association with HRV. Methods: Twenty eight individuals (69±7.76 years) were selected in a Preventive Medicine Center, who completed a questionnaire (WHOQOL-OLD). HRV data were collected for 20 minutes with a Polar RS800CX in a supine position. Results: Using median value as cut-off point, the sample was divided into two groups: WHOQOL-OLD ≥92 (N=15: older adults with better quality of life) and WHOQOL-OLD ≤91 (N=13: older adults with worse quality of life). Considering HRV, in the time domain, RMSSD and PNN50 showed higher values in WHOQOL-OLD ≥92 (P=0.0413 and P=0.0222, respectively). In the frequency domain, LF, HF and Total Power showed higher values in WHOQOL-OLD ≥92 (P=0.0195, P=0.0170 and P=0.0287, respectively). In the nonlinear domain, SD1 was significantly higher in WHOQOL-OLD ≥92 (P=0.0413), whereas DET% was significantly higher in WHOQOL-OLD≤91 (P=0.0253). Conclusions: Better quality of life is associated with good functioning of the ANS, represented by high HRV in three domains in older adults, with emphasis on the role of healthy lifestyle for healthy aging, improving autonomic function and, therefore, quality of life.