Functional Capacity in Obstructive Sleep Apnea

October 28, 2026 updated by: Musa Güneş, Karabuk University

Investigation of Functional Capacity in Patients With Obstructive Sleep Apnea

Obstructive sleep apnea syndrome (OSAS) is a condition characterized by a deterioration in respiratory function and an increase in the activity of accessory respiratory muscles. This condition can affect patients' use of their upper extremities during daily living activities. In this context, our study aimed to examine respiratory function, respiratory muscle strength and endurance, peripheral muscle strength, upper extremity functional exercise capacity, muscle oxygenation, and dyspnea in patients with OSAS, and to compare these parameters with those of healthy controls.

Study Overview

Status

Recruiting

Conditions

Study Type

Observational

Enrollment (Estimated)

52

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Turkey (Türkiye)
      • Karabük, Turkey (Türkiye)
        • Recruiting
        • Karabuk University, Physiotherapy and Rehabilitation Application and Research Center
        • Contact:

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

18 years to 65 years (Adult, Older Adult)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Probability Sample

Study Population

Individuals with a diagnosis of Obstructive Sleep Apnea Syndromeand healthy individuals will be included in the study.

Description

Inclusion Criteria:

  • Aged 18-65,
  • Diagnosis of Obstructive Sleep Apnea Syndrome (OSAS) confirmed by a pulmonologist following polysomnography,
  • An Apnea-Hypopnea Index (AHI) ≥5 for OSAS,
  • Willingness to participate in the study.

Exclusion Criteria:

  • Having severe orthopedic, neurological, or cardiac conditions,
  • Having a diagnosed pulmonary disease,
  • Having a history of-or currently experiencing-a psychiatric or neurological disorder,
  • Not being willing to participate in the study.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Observational Models: CASE_CONTROL
  • Time Perspectives: CROSS_SECTIONAL

Cohorts and Interventions

Group / Cohort
Obstructive sleep apnea

Patients with obstructive sleep apnea syndrome will be included in the study.
Control Group

Healthy individuals will be included in the study.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Upper extremity exercise capacity
Time Frame: Baseline

Upper extremity exercise capacity will be evaluated with the six-minute pegboard and ring test (6-PBRT).
Baseline

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Pulmonary function (Forced vital capacity (FVC)
Time Frame: Baseline

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Forced vital capacity (FVC) will be measured.
Baseline
Pulmonary function (Forced expiratory volume in the first second (FEV1)
Time Frame: Baseline

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Forced expiratory volume in the first second (FEV1) will be measured.
Baseline
Pulmonary function (FEV1 / FVC)
Time Frame: Baseline

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. FEV1 / FVC will be measured.
Baseline
Pulmonary function (Flow rate 25-75% of forced expiratory volume (FEF 25-75%))
Time Frame: Baseline

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Flow rate 25-75% of forced expiratory volume (FEF 25-75%) will be measured.
Baseline
Pulmonary function (Peak flow rate (PEF))
Time Frame: Baseline

Pulmonary function will be evaluated using the spirometry, according to American Thoracic Society and European Respiratory Society criteria. Peak flow rate (PEF) will be measured.
Baseline
Peripheral muscle strength
Time Frame: Baseline

Peripheral muscle strength will be evaluated with a dynamometer.
Baseline
Respiratory Muscle Strength
Time Frame: Baseline

Maximal inspiratory (MIP) and maximal expiratory (MEP) pressures expressing respiratory muscle strength will be evaluated.
Baseline
Respiratory Muscle Endurance
Time Frame: Baseline

Respiratory muscle endurance will be assessed by the POWERbreathe Wellness (POWERbreathe, Inspiratory Muscle Training (IMT) Technologies Ltd., Birmingham, UK) device and the respiratory muscle endurance test at increased threshold load.
Baseline
Muscle oxygenation
Time Frame: Baseline

Muscle oxygenation assessment will be performed using the Moxy monitor (Moxy, Fortiori Design LLC, Minnesota, USA).
Baseline
Dyspnea
Time Frame: Baseline

Dyspnea is assessed with the modified Medical Research Council (mMRC) dyspnea scale. As the score increases, shortness of breath increases.
Baseline

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Karabuk University

Investigators

  • Principal Investigator: Rabia Hande Avcı, MD, Karabuk University
  • Study Director: Musa Güneş, PhD, Karabuk University
  • Principal Investigator: Ebrar Tülümenoğlu, MSc (c), Karabuk University
  • Principal Investigator: Nisa Nur Dönmez, MSc (c), Karabuk University

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

October 28, 2026

Primary Completion (Estimated)

October 28, 2027

Study Completion (Estimated)

October 30, 2027

Study Registration Dates

First Submitted

October 28, 2026

First Submitted That Met QC Criteria

October 28, 2026

First Posted (Actual)

November 3, 2026

Study Record Updates

Last Update Posted (Actual)

November 3, 2026

Last Update Submitted That Met QC Criteria

October 28, 2026

Last Verified

October 1, 2026

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • Karabuk_OUAS

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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