[O-RS-01-3] Sleep Apnea and Lateral Balance Instability in the Elderly.
Keywords:Sleep Apnea, Lateral balance instability, Elderly
Ameliorating postural instability and sleep disorders are common problem of geriatric health care. Since there is a previous study of sleep apnea and falls, it is important to investigate whether the elderly patient with sleep apnea syndrome exhibits increased postural sway. However, the relationship between profile of sleep apnea assessed by full polysomnography and postural stability in the elderly has not been elucidated.
We enrolled fourteen age-matched control subjects and 36 elderly with SAS. Each subject was evaluated by full polysomnography. Inclusion criteria for patients with SAS included a full overnight polysomnogram with an apnea-hypopnea index（AHI）greater than 20 events per hour. The recruit criteria for age-matched control subjects was defined as AHI＞15 without SAS-related symptoms. The study was approved by the institutional ethics committee. We evaluated the following data：length；of the CoP（ML and AP）, distances and the velocities of the CoP（ML and AP）.
The distance in ML direction with open-eyes in the elderly with SAS was significantly higher than that in age-matched control subjects, whereas no significant differences were found in the length and velocity in ML direction with open-eyes between the elderly with SAS and age-matched control subjects. The distance in ML direction with was significantly associated with hypopnea index, apnea-hypopnea index, apnea index and arousal index. In addition, the length in ML direction with open-eyes was significantly correlated with hypopnea index and apnea index. However, there was no significant correlation between the length, distance and velocity in AP direction and the polysomnographic findings. A stepwise linear regression analysis showed that apnea index was the only independent determinant of the distance in ML direction with open-eyes in elderly with SAS.
The present study found that sleep apnea has significant association with lateral balance instability in elderly with SAS.
We enrolled fourteen age-matched control subjects and 36 elderly with SAS. Each subject was evaluated by full polysomnography. Inclusion criteria for patients with SAS included a full overnight polysomnogram with an apnea-hypopnea index（AHI）greater than 20 events per hour. The recruit criteria for age-matched control subjects was defined as AHI＞15 without SAS-related symptoms. The study was approved by the institutional ethics committee. We evaluated the following data：length；of the CoP（ML and AP）, distances and the velocities of the CoP（ML and AP）.
The distance in ML direction with open-eyes in the elderly with SAS was significantly higher than that in age-matched control subjects, whereas no significant differences were found in the length and velocity in ML direction with open-eyes between the elderly with SAS and age-matched control subjects. The distance in ML direction with was significantly associated with hypopnea index, apnea-hypopnea index, apnea index and arousal index. In addition, the length in ML direction with open-eyes was significantly correlated with hypopnea index and apnea index. However, there was no significant correlation between the length, distance and velocity in AP direction and the polysomnographic findings. A stepwise linear regression analysis showed that apnea index was the only independent determinant of the distance in ML direction with open-eyes in elderly with SAS.
The present study found that sleep apnea has significant association with lateral balance instability in elderly with SAS.