Obstructive Sleep Apnea and Cognitive Decline: A Review of Potential Vulnerability and Protective Factors

Abstract

Around 40% of dementia risk is attributable to modifiable risk factors such as physical inactivity, hypertension, diabetes and obesity. Recently, sleep disorders, including obstructive sleep apnea (OSA), have also been considered among these factors. However, despite several epidemiological studies investigating the link between OSA and cognitive decline, there is still no consensus on whether OSA increases the risk of dementia or not. Part of the heterogeneity observed in previous studies might be related to some individual characteristics that modulate the association between OSA and cognitive decline. In this narrative review, we present these individual characteristics, namely, age, sex, menopause, obesity, diabetes mellitus, hypertension, cardiovascular diseases, smoking, excessive alcohol consumption, depression, air pollution, Apolipoprotein E ε4 allele, physical activity, and cognitive reserve. To date, large cohort studies of OSA and cognitive decline tended to statistically control for the effects of these variables, but whether they interact with OSA to predict cognitive decline remains to be elucidated. Being able to better predict who is at risk of cognitive decline when they have OSA would improve clinical management and treatment decisions, particularly when patients present relatively mild OSA.

Improving CPAP Adherence in Adults With Obstructive Sleep Apnea Syndrome: A Scoping Review of Motivational Interventions

“…Obstructive Sleep Apnea Syndrome (OSAS) is a sleep-related breathing disorder characterized by transient interruption of ventilation during sleep caused by complete or partial occlusion of the upper airway (McNicholas et al, 2007). Consequent oxygen desaturation, increased inspiratory effort, sleep fragmentation, and arousal from sleep (Lévy et al, 2015;Jennum et al, 2021) lead to excessive daytime sleepiness, cardiovascular, and metabolic diseases (Pépin et al, 2019;Visniauskas et al, 2021), cognitive and memory impairments (Alomri et al, 2021;Huang et al, 2021;Legault et al, 2021), and mood disorders (Garbarino et al, 2020).…”

Sleep‐disordered breathing was associated with lower health‐related quality of life and cognitive function in a cross‐sectional study of older adults

“…Several studies have now linked SDB to dementia risk 18,19 and to biomarkers of AD and vascular dementia 41 . This association, however, is not conclusive 20,21,42 . Some studies have relied upon a clinical diagnosis of SDB 43 which is more likely to be symptomatic with daytime sleepiness, a symptom itself associated with dementia risk 44 .…”

“…Dementia, however, is a significant health issue for older people, and there are several mechanisms by which SDB may potentiate the neurodegenerative processes that lead to dementia due to Alzheimer's disease (AD) and/or vascular pathologies 13–17 . SDB has been linked to an increased risk of both impaired cognitive function, which usually precedes dementia, and of dementia itself, albeit inconsistently 18–22 …”

Short-Term Effects of a Multidisciplinary Residential Rehabilitation Program on Perceived Risks, Confidence Toward Continuous Positive Airway Pressure Treatment, and Self-Efficacy in a Sample of Individuals Affected by Obstructive Sleep Apnea Syndrome

“…This might be a piece of very crucial information because profiling the individual temperament through the questionnaires is a timeconsuming activity. Such questionnaires, which consist of a very large number of items, might not be completely suitable in the case of individuals affected by OSA syndrome, who generally experience a higher level of mental fatigue, as well as attentional difficulties and a lower level of alertness (Llewellyn et al, 2008;Wilson et al, 2013;Alomri et al, 2021;Legault et al, 2021;Scarpina et al, 2021).…”

“…Due to the negative side effects of OSA syndrome on cognition (Alomri et al, 2021;Legault et al, 2021), all participants performed a global assessment of the cognitive functioning through the Mini-Mental State Examination (Folstein et al, 1975;Italian version;Magni et al, 1996), the Clock-Drawing Test (Rouleau et al, 1992;Italian version: Siciliano et al, 2016), and the Frontal Assessment Battery (Dubois et al, 2000;Italian version: Appollonio et al, 2005).…”