Visual recognition of the elderly concerning risks of falling or stumbling indoors in the home: -comparison of visual attention points among elderly, middle aged and young individuals-.

OBJECTIVE: The objective of this study was to verify the recognition of dangers and obstacles within a house in the elderly when walking based on analyses of gaze point fixation. MATERIALS AND METHODS: The rate of recognizing indoor dangers was compared among 30 elderly, 14 middle-aged and 11 young individuals using the Eye Mark Recorder. RESULTS: 1) All of the elderly, middle-aged and young individuals showed a high recognition rate of 100% or near 100% when ascending outdoor steps but a low rate of recognizing obstacles placed on the steps. They showed a recognition rate of about 60% when descending steps from residential premises to the street. The rate of recognizing middle steps in the elderly was significantly lower than that in younger and middle-aged individuals. Regarding recognition indoors, when ascending stairs, all of the elderly, middle-aged and young individuals showed a high recognition rate of nearly 100%. When descending stairs, they showed a recognition rate of 70-90%. However, although the recognition rate in the elderly was lower than in younger and middle-aged individuals, no significant difference was observed. 2) When moving indoors, all of the elderly, middle-aged and young individuals showed a recognition rate of 70%-80%. The recognition rate was high regarding obstacles such as floors, televisions and chests of drawers but low for obstacles in the bathroom and steps on the path. The rate of recognizing steps of doorsills forming the division between a Japanese-style room and corridor as well as obstacles in a Japanese-style room was low, and the rate in the elderly was low, being 40% or less. CONCLUSION: The rate of recognizing steps of doorsills as well as obstacles in a Japanese-style room was lower in the elderly in comparison with middle-aged or young individuals.

Clinical significance of sleep-related breathing disorder in narcolepsy.

Both the influence of comorbid obstructive sleep apnea-hypopnea syndrome (OSAHS) on daytime sleepiness and its pathological mechanism in 10 narcoleptic patients was studied. Mild elevation of esophageal negative pressure and obstruction in the velopharyngeal area, as observed by upper airway magnetic resonance imaging, during apneic episodes was observed in the subjects. Severity of the disorder was correlated positively with body mass index, and the latencies of the multiple sleep latency tests were not improved with nasal continuous positive airway pressure treatment in subjects. Pathogenesis of OSAHS in narcolepsy was thought to be almost similar to typical OSAHS, and that the disorder seemed to lack a pathological influence on daytime sleepiness.

Clinical significance of cataplexy and HLADR1501 in narcolepsy.

Clinical symptoms and multiple sleep latency test (MSLT) measures among narcoleptic patients with both cataplexy and HLADR1501 were compared with cataplexy-free narcoleptic patients with a positive finding of HLADR1501 and cataplexy-free patients without HLADR1501. Both mean sleep onset latencies and rapid eye movement (REM) latencies on MSLT were shorter in the patients with cataplexy compared with the cataplexy-free patients. In four cataplexy-free patients without HLADR1501, nocturnal sleep was remarkably long and their excessive daytime sleepiness did not respond to treatment. The findings suggest that the severity and disease mechanism of narcolepsy might become heterogenous when cataplexy and HLADR1501 are considered.

Subjective sleep quality and suggested immobilization test in restless leg syndrome and periodic limb movement disorder.

The severity of restless leg syndrome (RLS) and/or periodic limb movement disorder (PLMD) was investigated by using a suggested immobilization test (SIT) and by measuring the influence of these disorders on the subjective sleep quality as assessed by the Pittsburgh Sleep Quality Index (PSQI). Patients with RLS and those with both RLS and PLMD showed remarkably high values for PSQI and SIT, whereas patients with PLMD only showed normal values for PSQI. These findings suggest that there is only a small pathological significance for periodic limb movements, and demonstrate the efficacy of SIT and PSQI for evaluating the severity of these disorders.