Aging and gender effects on heart rate variability in healthy Japanese elderly

Abstract

s from The Japanese Journal The Autonomic Nervous System #1 Evaluation of sleep quality by spectral electroencephalographic entropy using nasal continuous positive airway pressure recorded by a portable biosignal measuring device Noriko Ohisa, Hiromasa Ogawa, Toshiya Irokawa, Hajime Kurosawa, Katsumi Yoshida Clinical Laboratory Department, Tohoku University Hospital, Sendai 980-8574, Japan Health Administration Center, Tohoku University, Japan Medical Technology Department, Tohoku University School of Health Sciences, Japan Polysomnography is the gold standard for the diagnosis of obstructive sleep apnea/hypopnea syndrome (OSAHS). However, the procedure is very expensive and much time is required for analyzing polysomnography repeatedly. Here we present data by electroencephalographic (EEG) spectral entropy, calculated using MemCalc, used as an index for evaluating sleep quality. EEG spectral entropy was evaluated and was compared to the results of polysomnography. Twelve subjects with obstructive sleep apnea/hypopnea syndrome participated in this study. They were treated with nasal continuous positive airway pressure (CPAP). The EEG was recorded by means of a portable biosignal measuring (PBSM) device and polysomnography was recorded using Alice III, during a 10-hour period from 20:00 to 6:00. Spectral entropy was aligned with the sleep stages extracted manually from the polysomnography recordings, and was compared in subjects with or without treatment with continuous positive airway pressure. There was a statistically significant decrease in spectral entropy (from −1.369 to −1.206; pb0.05) when the subjects were treated with continuous positive airway pressure compared to when the subjects had only received a pretreatment with continuous positive airway pressure. In 10 subjects treated with continuous positive airway pressure there was a cut-off at −1.313 for the reduction of negative values of spectral entropy. We conclude that the spectral entropy, calculated using MemCalc, appears to be a viable alternative index for evaluating sleep quality in positive airway pressure treatment. (The Autonomic Nervous System, 47: 271–276, 2010) doi:10.1016/j.autneu.2011.08.010 #2 Aging and gender effects on heart rate variability in healthy Japanese elderly Akira Katagiri, Masato Asahina, Yoshikatsu Fujinuma, Yuichi Akaogi, Yoshitaka Yamanaka, Takeshi Fukushima, Hitoshi Shinotou, Takamichi Hattori, Toshiomi Asahi Department of Neurology, Chiba University School of Medicine, Chiba 260-8670, Japan Asahi Neurology and Rehabilitation Hospital, Chiba 270-0022, Japan The aim of this study was to evaluate the effects of aging and gender on frequency-domain indexes of heart rate variability (HRV) in healthy Japanese elderly. The subjects were 45 healthy Japanese aged 65 or over (28 men and 15 women, aged 73.4+5.2 years) who were undergoing electrocardiography. R–R intervals of 300 beats were analyzed spectrally into low frequency (LF, 0.04–0.15 Hz) and high-frequency (HF, 0.15–0.4 Hz) components, with normalized unit LF and HF (nuLF and nuHF), and LF/HF obtained. The HRV parameter means were: LF 161±226 ms, HF 130± 174 ms, LF/HF 2.3±3.3, nuLF 53.0±20.5% and nuHF 39.5±16.8%. LF, HF and LF/HF were logarithmically distributed, and converted. Log LF was 1.91±0.52, log HF 1.78±0.56 and log LF/HF 0.13±0.44. No significant correlations were seen between HRV parameters and age, or between HRV and gender. We conclude that when evaluating HRV parameters in the healthy Japanese elderly, the HRV decrease found in elderly subjects may be more difficult to explain than when found in the young. (The Autonomic Nervous System, 47: 381–385, 2010) doi:10.1016/j.autneu.2011.08.011 #3 Computer-simulated detection of true SSR waveforms on the back of the hand Hiroko Mitani, Yoji Ishiyama Department of Clinical Physiology and Medical Applied Engineering, School of Health Sciences, Kyorin University, Tokyo 192-8508, Japan To infer true sympathetic skin response (SSR) waveforms on the dorsal surface of the hand, we studied SSR potential polarity and