Effect of obstructive sleep apnea syndrome on sleep architecture: comparative study between geriatrics and middle-aged adult patients

Abstract

Background
Obstructive sleep apnea (OSA) is a prevalent sleep disordered breathing in geriatrics but still frequently undiagnosed. Sleep architecture changes with ageing. Geriatrics spend more time in the N1, N2 than in N3, REM. Also, there are more frequent awakenings, arousals and sleep stage shifts. This leads to decrease in sleep efficiency. Geriatric patients with OSA have more affected sleep architecture than middle-aged adults.


The aim
This work aimed to assess and compare sleep architecture changes in geriatrics versus middle-aged adult patients with OSA syndrome.


Patients and methods
This comparative study conducted in chest department Menoufia University Hospitals included 50 patients divided to two equal groups; geriatric group age 65 years old or more and middle-aged adult group aged from 18 to 50 years old. All patients were complaining of symptoms suggestive of OSA. All patients underwent sleep questionnaires and Polysomnography using model; Philipsrespironic alice6.


Results
There was no statistically significant difference between the studied groups regarding sex, smoking, co morbidities, BMI and symptoms. Regarding changes in sleep architecture, geriatric group showed a significantly higher Sleep latency and wakefulness after sleep onset in comparison to middle-aged adults (P=0.004 and 0.039, respectively) versus significantly lower Sleep efficiency, N3%, REM% (P=0.009,0.011 and 0.001, respectively). The median Total Apnea-Hypopnea index was 40.2 (/h sleep) in geriatric group and 35.4 in middle-aged adult group. Regarding severity of OSA; geriatric group showed mild OSA in five (20%) patients, moderate in five (20%) patient and severe in 15 (60%) patients. Middle-aged adults showed mild OSA in 10 (40%) patients, moderate in two (8%) patients, and severe in 13 (52%) patients.


Conclusions
Sleep architecture is affected in all OSA patients, but these changes are more obvious in geriatric patients. Geriatric patients have higher wakefulness after sleep onset and sleep latency. On the other hand, they have a lower N3%, REM% and sleep efficiency.