Characteristic Autonomic Nervous Activity of Institutionalized Elders with Dementia

This study clarified the characteristic autonomic nervous activity of institutionalized elders diagnosed with dementia using Hasegawa’s Dementia Scale-Revised. Twenty-six healthy adult persons (HPs) in their 20 s - 40 s met the inclusion criteria, and 16 persons (27.6 ± 8.2 years old) completed the research procedure. Of 70 persons with dementia (PDs) residing at the one geriatric health services facilities, only 24 persons met the inclusion criteria, and only nine (N = 9, 83.44 ± 9.45 years old) completed the procedure. Actigraph and ambulatory electrocardiographic instruments measuring autonomic nervous activity were attached to the subjects for 24 hours. Activities and behaviors of PDs and HPs were observed by clinically experienced staff nurses and care workers. High frequency (HF) power indicating parasympathetic activity and LF/HF ratio indicating sympathetic activity were calculated. When awake, PDs’ LF/HF ratio was significantly lower than HP’s (Z = -2.60, p < 0.01), showing significant differences in the LF/HF ratios between waking and sleeping, more than those of the PDs (p < 0.001). Similarly, when awake, significant positive correlations were observed in the LF/HF ratio and actigraph activity count (AC) in 11 HPs and 3 PDs (range r = 0.17 to 0.49, p < 0.05);however, significant negative correlation was found in HF and AC of 12 HPs and 3 PDs (range r = -0.55 to -0.18, p < 0.05). While sleeping, significant positive correlations were observed in LF/HF and AC of 3 HPs and 1 PD (range r = 0.35 to 0.42, p < 0.05) and significant negative correlation was found in the HF and AC of 1 HP (r= -0.32, p < 0.001) and 1 PD (r = -0.32, p < 0.05). The mean value of LF/HF in a wakeful state was significantly lower for PDs than HPs. Combined results of behavioral observation, actigrapy and heart rate variability (HRV) analyses suggested that PDs showed positive correlations between LF/HF and AC in a wakeful state. Compared to those who showed no positive correlation, they did not require much nursing care.

Characteristics of Sleep and Autonomic Activity in Active Older Adults Based on Metabolic Age: A Comparative Case Study

Background: The balance of autonomic nervous system activity and its relationship with body composition, sleep quality, and activities of daily living among older people is still unclear. Purpose: This comparative case study examined the characteristics of body composition, sleep quality, and autonomic nerve activity in active older adults with a younger body age-calculated from age trends in body composition and basal metabolic rate. Methods: We selected two cases with a metabolic age younger than their actual age. They had good sleep quality, no sarcopenia, strong muscle and grip strength, and balanced autonomic nervous system activity. They were compared with two other age- and gender-matched cases, who had poor sleep quality, unbalanced autonomic nervous system activity, and had a physical age closer to their actual age. Results: Older adults with more muscle mass and higher basal metabolism were younger than their actual age, had a better sleep status, and had a good balance of autonomic nervous activity during exercise stimulation. They also had lower percentages of body and visceral fat and higher percentages of body water. Conclusion: Two cases had a metabolic age younger than their actual age were found to be much younger than their actual age. However, the older adults with normal muscle mass and basal metabolic rate had poor sleep status and no sympathetic hyperactivity during exercise simulation.