Dados do Trabalho

Título

Age-related sleep fragmentation

Introdução

Obstructive sleep apnea (OSA) is associated with sleep fragmentation. The ventilatory disruption ultimately causes physiological changes that affect arousal control in central nervous system (CNS). Arousals are, in fact, a diagnostic criterion for marking hypopneas in the polysomnography (PSG). Age is also related to sleep maintenance. Current evidence suggests that arousal index increases with age. However, to date, it is not known any study with a large group of individuals evaluating the arousal index (AI) in the PSG in relation to age, controlling to other causes of sleep disruption.

Objetivo

This study aimed to evaluate the correlation of AI with age, controlling for apnea and hypopnea index (AHI) and periodic leg movement index (PLMI).

Métodos

A retrospective analysis of all 30159 PSG studies performed between 2008 and 2016 in patients of a large sleep center was conducted. Exclusion criteria were repeated PSG of the same patient, split-night or CPAP PSG studies, age below 18 years and use of sleep-inducing drugs in the night of the PSG. Thus, 21961 eligible PSG reports were analyzed.
A multiple regression analysis was conducted, with AI as dependent variable and age, AHI, and PLMI as independent variables.

Resultados

There were positive correlations between increased AI and AHI (beta=0.68, p<0,001), PLMI (beta=0.10, p<0,001), and age (beta=0.01, p=0.01).

Conclusões

As expected, the main predictor factor of arousal index was AHI, and the second was PLMI. Even controlling for those two main causes of sleep fragmentation, age continued to be significantly related to the arousal index. This result gives new insights about CNS resilience to arousing stimuli changing with aging.

Palavras-chave

Sleep fragmentation, ageing, polysomnography, arousal index