Cognitive Function in Obstructive Sleep Apnea

NCT07364318 | Recruiting

• 2 other identifiers: CUFM1DN-0111202431122025VEGA 1/0075/25
• Study Type: observational
• Target: 30
• Locations: 1 country
• Sites: 1

Brief Summary

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.

Conditions

OSA - Obstructive Sleep Apnea; Cognitive Functions

Keywords

Cognitive Function; Positive Airway Pressure Therapy; Obstructive Sleep Apnea; Neuroimaging; Biomarkers; Vascular Changes; Metabolic Changes

Outcome Measures

Primary Outcomes (20)

• Rey Auditory - Verbal Learning Test (RAVLT)

  Measure of verbal episodic memory, encompassing immediate recall, learning across trials, delayed recall, and recognition. Units: total number of correctly recalled words (0-75); z-score. Higher scores indicate better performance.

  Baseline

• Figure Copy Task

  A visuoconstructional task used to assess visual perception, spatial planning, and visual memory. Units: score 0-24 points; z-score. Higher scores indicate better performance.

  Baseline

• Controlled Oral Word Association Test (COWAT)

  A verbal fluency task requiring rapid generation of words beginning with specified letters. It assesses phonemic fluency, executive function, and lexical retrieval. Units: number of correct words generated per minute; z-score. Higher scores indicate better performance.

  Baseline

• Category Fluency Test

  A semantic fluency measure where subjects list as many words from a given category. It evaluates semantic memory and executive retrieval processes. Units: number of correct words generated per minute; z-score. Higher scores indicate better performance.

  Baseline

• Trail Making Test (TMT)

  A two-part test evaluating processing speed, visual search, attention, and task-switching. Units: completion time in seconds; z-score. Shorter completion times indicate better performance.

  Baseline

• The Stroop Color and Word Test

  Measure of selective attention, processing speed, cognitive flexibility, and inhibitory control. Units: completion time in seconds; z-score. Shorter completion times indicate better performance.

  Baseline

• Digit Span

  A working memory test comprising forward and backward recall of digit sequences. Assesses attention, concentration, and short-term memory. Units: total score (0-14 points); z-score. Higher scores indicate better performance.

  Baseline

• Montreal Cognitive Assessment (MoCA)

  General cognition screening targeting attention, executive function, memory, language, visuospatial abilities, and orientation. Units: total score (0-30 points); ≥26 = normal cognition. Higher scores indicate better performance.

  Baseline

• Generalized Anxiety Disorder 7-item scale (GAD - 7)

  A 7-item self-report questionnaire to screen and assess the severity of generalized anxiety disorder. Items are rated on a 4-point scale. Units: total score (0-21 points); cut-off ≥ 10. Higher scores indicate greater anxiety symptom severity.

  Baseline

• Patient´s Health Questionnaire (PHQ - 9)

  A 9-item scale assessing depression severity based on DSM IV criteria. Items are rated on a 4-point scale. Units: total score (0-27 points); cut-off ≥ 10. Higher scores indicate greater depressive symptom severity.

  Baseline

• Rey Auditory - Verbal Learning Test (RAVLT) 12 moths

  Measure of verbal episodic memory, encompassing immediate recall, learning across trials, delayed recall, and recognition. Units: total number of correctly recalled words (0-75); z-score. Higher scores indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Figure Copy Task 12 months

  A visuoconstructional task used to assess visual perception, spatial planning, and visual memory. Units: score 0-24 points; z-score. Higher scores indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Controlled Oral Word Association Test (COWAT) 12 months

  A verbal fluency task requiring rapid generation of words beginning with specified letters. It assesses phonemic fluency, executive function, and lexical retrieval. Units: number of correct words generated per minute; z-score. Higher scores indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Category Fluency Test 12 months

  A semantic fluency measure where subjects list as many words from a given category. It evaluates semantic memory and executive retrieval processes. Units: number of correct words generated per minute; z-score. Higher scores indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Trail Making Test (TMT) 12 months.

  A two-part test evaluating processing speed, visual search, attention, and task-switching. Units: completion time in seconds; z-score. Shorter completion times indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• The Stroop Color and Word Test 12 months.

  Measure of selective attention, processing speed, cognitive flexibility, and inhibitory control. Units: completion time in seconds; z-score. Shorter completion times indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Digit Span 12 months.

  A working memory test comprising forward and backward recall of digit sequences. Assesses attention, concentration, and short-term memory. Units: total score (0-14 points); z-score. Higher scores indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Montreal Cognitive Assessment (MoCA) 12 months.

  General cognition screening targeting attention, executive function, memory, language, visuospatial abilities, and orientation. Units: total score (0-30 points); ≥26 = normal cognition. Higher scores indicate better performance. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Generalized Anxiety Disorder 7-item scale (GAD - 7) 12 months.

  A 7-item self-report questionnaire to screen and assess the severity of generalized anxiety disorder. Items are rated on a 4-point scale. Units: total score (0-21 points); cut-off ≥ 10. Higher scores indicate greater anxiety symptom severity. Assessments will be performed after 12 months.

  Change from baseline to 12 months

• Patient´s Health Questionnaire (PHQ - 9) 12 months.

  A 9-item scale assessing depression severity based on DSM IV criteria. Items are rated on a 4-point scale. Units: total score (0-27 points); cut-off ≥ 10. Higher scores indicate greater depressive symptom severity. Assessments will be performed after 12 months.

  Change from baseline to 12 months

Secondary Outcomes (14)

• Apnea-Hypopnea Index (AHI)

  Baseline

• Apnea-Hypopnea Index (AHI) 12 months

  12 months

• Positive Airway Pressure (PAP) Therapy Adherence

  12 months

• Pittsburgh Sleep Quality Index (PSQI)

  Change from baseline to 12 months

• Epworth Sleepiness Scale (ESS)

  Change from baseline to 12 months

Study Arms (1)

Newly diagnosed OSA

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).

Eligibility Criteria

• Age: 18 Years - 65 Years
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)
• Sampling Method: Non-Probability Sample

Study Population

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.

You may qualify if:

• Informed consent.
• Age 18 - 65 years.
• 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).
• Able to accomplish relevant tests and follow-up.

You may not qualify if:

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

Sponsors & Collaborators

• University Hospital Bratislava: collaborator
• Slovak Academy of Sciences: collaborator
• Comenius University: lead

Study Sites (1)

1st Department of Neurology, Faculty of Medicine, Comenius University and University Hospital Bratislava, Slovakia

Bratislava, 813 72, Slovakia

RECRUITING

Related Publications (7)

• Sehr T, Akgun K, Benkert P, Kuhle J, Ziemssen T, Brandt MD. Effects of obstructive sleep apnea treatment on neurodegenerative biomarker neurofilament light chain and cognitive performance. J Sleep Res. 2024 Oct;33(5):e14164. doi: 10.1111/jsr.14164. Epub 2024 Feb 13.

  PMID: 38351662 RESULT

• Xue X, Zhao Z, Zhao LB, Gao YH, Xu WH, Cai WM, Chen SH, Li TJ, Nie TY, Rui D, Ma Y, Qian XS, Lin JL, Liu L. Gut microbiota changes in healthy individuals, obstructive sleep apnea patients, and patients treated using continuous positive airway pressure: a whole-genome metagenomic analysis. Sleep Breath. 2024 Nov 26;29(1):11. doi: 10.1007/s11325-024-03185-z.

  PMID: 39589660 RESULT

• Silva WA, Almeida-Pititto B, Santos RB, Aielo AN, Giatti S, Parise BK, Souza SP, Vivolo SF, Lotufo PA, Bensenor IM, Drager LF. Obstructive sleep apnea is associated with lower adiponectin and higher cholesterol levels independently of traditional factors and other sleep disorders in middle-aged adults: the ELSA-Brasil cohort. Sleep Breath. 2021 Dec;25(4):1935-1944. doi: 10.1007/s11325-021-02290-7. Epub 2021 Feb 15.

  PMID: 33590375 RESULT

• Salari N, Khazaie H, Abolfathi M, Ghasemi H, Shabani S, Rasoulpoor S, Mohammadi M, Rasoulpoor S, Khaledi-Paveh B. The effect of obstructive sleep apnea on the increased risk of cardiovascular disease: a systematic review and meta-analysis. Neurol Sci. 2022 Jan;43(1):219-231. doi: 10.1007/s10072-021-05765-3. Epub 2021 Nov 19.

  PMID: 34797460 RESULT

• Durtette A, Dargent B, Gierski F, Barbe C, Deslee G, Perotin JM, Henry A, Launois C. Impact of continuous positive airway pressure on cognitive functions in adult patients with obstructive sleep apnea: A systematic review and meta-analysis. Sleep Med. 2024 Nov;123:7-21. doi: 10.1016/j.sleep.2024.08.019. Epub 2024 Aug 22.

  PMID: 39226674 RESULT

• Bubu OM, Andrade AG, Umasabor-Bubu OQ, Hogan MM, Turner AD, de Leon MJ, Ogedegbe G, Ayappa I, Jean-Louis G G, Jackson ML, Varga AW, Osorio RS. Obstructive sleep apnea, cognition and Alzheimer's disease: A systematic review integrating three decades of multidisciplinary research. Sleep Med Rev. 2020 Apr;50:101250. doi: 10.1016/j.smrv.2019.101250. Epub 2019 Dec 12.

  PMID: 31881487 RESULT

• Xu H, Liu Y, Li C, Li X, Shen L, Wang H, Liu F, Zou J, Xia Y, Huang W, Liu Y, Gao Z, Fu Y, Wang F, Huang S, Song Z, Song F, Gao Y, Peng Y, Zou J, Zhu H, Liu S, Li L, Zhu X, Xiong Y, Hu Y, Yang J, Li Y, Gao F, Guo Q, Huang H, Zhang W, Li J, Chen Y, Dong P, Yang J, Lv J, Wang P, Sun Y, Qian B, Yaffe K, Guan J, Yi H, Leng Y, Yin S. Effects of Continuous Positive Airway Pressure on Neuroimaging Biomarkers and Cognition in Adult Obstructive Sleep Apnea: A Randomized Controlled Trial. Am J Respir Crit Care Med. 2025 Apr;211(4):628-636. doi: 10.1164/rccm.202406-1170OC.

  PMID: 39998447 RESULT

Biospecimen

Retention: SAMPLES WITH DNA

blood and saliva

MeSH Terms

Conditions

Sleep Apnea, Obstructive

Condition Hierarchy (Ancestors)

Sleep Apnea Syndromes; Apnea; Respiration Disorders; Respiratory Tract Diseases; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Nervous System Diseases

Study Officials

• Peter Turcani, prof. MD PhD.

  1st Department of Neurology, Faculty of Medicine, Comenius University and University Hospital Bratislava, Slovakia

  STUDY DIRECTOR

Central Study Contacts

Branislav Kollar, prof. MD PhD. MPH.

CONTACT

+421 948 334 417; b.kollar.md@gmail.com

Stela Biathova, MA

CONTACT

+421 905 218 668; sbiathova@gmail.com

Study Design

• Study Type: observational
• Observational Model: COHORT
• Time Perspective: PROSPECTIVE
• Target Duration: 12 Months
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: November 14, 2025
• First Posted: January 23, 2026
• Study Start: November 1, 2024
• Primary Completion (Estimated): August 31, 2027
• Study Completion (Estimated): December 31, 2027
• Last Updated: January 23, 2026

Record last verified: 2026-01

Data Sharing

• IPD Sharing: Will not share

Locations

SL (1)