Cognitive Function in Obstructive Sleep Apnea (CUFM1DN)

Comenius University

Status: Enrolling

Conditions: OSA - Obstructive Sleep Apnea; Cognitive Functions

Study type: Observational

Funder types: Other

Identifiers

NCT07364318

CUFM1DN-0111202431122025

VEGA 1/0075/25 (Other Grant/Funding Number)

Details and patient eligibility

About

Obstructive sleep apnea (OSA) is the most common sleep-related breathing disorder and has been increasingly recognized as a contributor to cognitive decline and a potential risk factor for neurodegeneration. Previous studies have identified several associated comorbidities, including vascular dysfunction, metabolic alterations, and neuroinflammatory changes. However, the impact and underlying interplay of these pathophysiological mechanisms remain poorly understood due to the lack of integrated, multidimensional assessment. This prospective, observational, longitudinal cohort study aims to investigate cognition and OSA-related physiological and pathophysiological processes in 100 adults newly diagnosed with OSA, who have no history of chronic diseases (except for overweight and obesity) and are not receiving chronic medication. A subgroup of patients with moderate to severe OSA indicated for positive airway pressure (PAP) therapy will be followed to evaluate its long-term effects on cognitive function and related mechanisms. All participants will undergo polysomnography (PSG), comprehensive neuropsychological assessment, brain MRI with volumetric analysis, biomarker profiling from blood and saliva, and evaluation of endothelial function, baroreflex sensitivity, and gut microbiome composition at baseline and after 12 months. PAP adherence will be continuously monitored. The primary objective of this study is to characterize the profile of cognitive impairment associated with OSA. Secondary exploratory analyses will focus on factors contributing to neurocognitive dysfunction in OSA.

Full description

1. Background OSA is a multifaceted sleep disorder characterized by repeated episodes of upper airway obstruction during sleep, leading to significant reductions in airflow and oxygenation. Beyond its primary respiratory manifestations, OSA is associated with major comorbidities such as cardiovascular, metabolic, and neurocognitive disorders, affecting overall health and quality of life. Epidemiological data suggest that OSA affects nearly one billion individuals worldwide, yet remains markedly underdiagnosed, particularly in middle-aged and older adults. Chronic intermittent hypoxia and sleep fragmentation have been implicated in the disruption of neural networks involved in attention, executive function, memory, and emotion regulation. Neuroimaging studies further support these findings, revealing region-specific brain alterations such as hippocampal and cortical atrophy, white-matter hyperintensities, and changes in cerebral perfusion and metabolism. These mechanisms may contribute to accelerated brain aging and increase the vulnerability to neurodegenerative processes. With the global rise in dementia and aging populations, identifying modifiable contributors to cognitive decline is critical. Given that OSA is a treatable condition, timely diagnosis and effective management may represent one of the most accessible interventions to prevent or delay cognitive deterioration in vulnerable populations.
2. Aim of the study The primary aim of this study is to perform a detailed cognitive assessment in patients with OSA. The investigators seek to analyze the baseline prevalence, severity, and pattern of cognitive deficits in this population to gain a clearer understanding of the initial cognitive status from which potential therapeutic or disease-related changes may occur. The secondary aims of this study are exploratory. The investigators plan to investigate potential associations between cognitive impairment and a spectrum of PSG, sleep-related, neuroimaging, anthropometric, laboratory, and vascular measures. The investigators aim to compare the sensitivity of the Montreal Cognitive Assessment (MoCA) with that of a comprehensive neuropsychological battery. Furthermore, the investigators will evaluate the longitudinal effects of PAP therapy on cognition and the related processes under investigation.
3. Inclusion criteria Patients with newly diagnosed OSA who have no history of other chronic diseases except for overweight and obesity, are not taking any medication, and are aged between 18 and 65 years.
4. Study methodology This is a prospective, observational, single-centre cohort study conducted at the Sleep Laboratory of the 1st Department of Neurology, Faculty of Medicine, Comenius University and University Hospital Bratislava. One hundred adults with OSA will be examined at baseline and after 12 months. As part of standard clinical care, all participants will undergo overnight diagnostic PSG to confirm the OSA diagnosis and determine its severity. Patients indicated for PAP therapy will start treatment according to clinical indications, with adherence monitored via device memory cards. Additional research assessments include neuropsychological testing, brain MRI with volumetry, blood and saliva biomarker analysis, assessment of vascular functions, anthropometric measurements, oxidative stress evaluation, and gut microbiome analysis. All assessments will be performed by trained research personnel in a standardized order. Participants will first be hospitalized to undergo PSG to confirm the OSA diagnosis. After confirmation, those meeting the inclusion criteria and providing informed consent will be enrolled in the study.
5. What are the possible benefits and risks of participating? Participants may benefit from early detection of cognitive dysfunction, metabolic or vascular abnormalities, and sleep-related pathology. Risks associated with study participation are minimal and primarily related to standard blood sampling and mild discomfort during assessments. No experimental or invasive interventions are applied.

Enrollment: 30 estimated patients

Sex: All

Ages: 18 to 65 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

1. Informed consent.
2. Age 18 - 65 years.
3. Newly diagnosed OSA according to the criteria of the American Academy of Sleep Medicine Guidelines (overnight PSG with an AHI ≥5 events per hour, hypopneas defined by ≥ 10 seconds of airflow reduction accompanied by ≥ 3% desaturation or an arousal).
4. Able to accomplish relevant tests and follow-up.

Exclusion criteria

1. History of any chronic disease other than overweight and obesity.
2. Severe psychiatric condition that could affect cognitive functions.
3. Chronic use of medication or nicotine that may affect the study results.
4. Prior neuropsychological assessment less than 6 months before the start of the research.
5. Prior therapy for OSA (i.e., CPAP, upper airway surgery, or oral appliance).
6. Motor or sensory deficits that would significantly complicate test administration.
7. Patients who do not have Slovak as their native language actively used in daily communication.
8. Considered by the study team as not suitable for enrollment based on clinical judgment.

Trial design

30 participants in 1 patient group

Newly diagnosed OSA

Description:

Newly diagnosed OSA according to the criteria of the American Academy of Sleep Medicine Guidelines (overnight PSG with an AHI ≥5 events per hour, hypopneas defined by ≥ 10 seconds of airflow reduction accompanied by ≥ 3% desaturation or an arousal).