Respiratory Muscle Strength and Endurance Cut-Offs in Multiple Sclerosis

Summary

Multiple sclerosis (MS) is a chronic and progressive autoimmune disease of the central nervous system characterized by inflammation, demyelination, and axonal degeneration. Depending on lesion localization and disease severity, individuals with MS may develop a wide range of neurological manifestations affecting motor and sensory functions.

Current evidence indicates that pulmonary function impairments may occur in individuals with MS even in the absence of overt respiratory symptoms. Compared with healthy individuals, people with MS have been reported to exhibit significantly reduced values in several respiratory parameters, particularly respiratory muscle strength. Moreover, these reductions appear to become more pronounced in parallel with increasing Expanded Disability Status Scale (EDSS) scores, regardless of disease duration. Indeed, previous studies have demonstrated that even individuals with MS who have mild disability levels (EDSS 0-4.5) experience significant declines in respiratory muscle strength, pulmonary function, and functional exercise capacity compared with healthy controls.

These findings suggest that the respiratory system may be affected not only in the advanced stages of MS but also during the early phases of the disease, with functional impairments emerging before clinically evident respiratory complaints arise. Despite this, the existing literature lacks studies that define clear, clinically applicable cut-off values for respiratory muscle strength and endurance that can discriminate disability levels in individuals with MS. This gap highlights the absence of objective criteria that clinicians can rely on for early detection and for planning targeted rehabilitation interventions.

The present study aims to address this gap by identifying optimal cut-off points for respiratory muscle strength and endurance in individuals with MS to facilitate early and accurate discrimination of disability status. By doing so, this research seeks to make an original contribution to the literature. The findings are expected to support the standardization of respiratory assessment processes in clinical practice, thereby improving patient quality of life and enhancing the efficiency of healthcare services. Furthermore, the results will provide a strong scientific basis for integrating respiratory function assessments into MS follow-up protocols and will offer a methodological framework for future intervention-oriented studies.

Conditions

• Multiple Sclerosis

Interventions

OTHER

Respiratory Muscle Strength and Endurance Assessment

Participants will undergo a comprehensive assessment of respiratory muscle function, including respiratory muscle strength measured by maximal inspiratory and expiratory pressures and respiratory muscle endurance evaluated using an incremental threshold loading protocol. Pulmonary function will be assessed by spirometry. These assessments will be conducted to determine optimal cut-off values of respiratory muscle strength and endurance for discriminating disability status in individuals with multiple sclerosis and to examine their associations with clinical outcomes.

Sponsors & Collaborators

• Selcuk University

  lead OTHER

Principal Investigators

• İsmail ÖZSOY, Assoc. Prof. Dr. · Selcuk University, Faculty of Health Sciences, Department of Physiotherapy and Rehabilitation, Konya, Türkiye

• Zehra KORKUT, Assist. Prof. Dr. · Selcuk University, Faculty of Health Sciences, Department of Physiotherapy and Rehabilitation, Konya, Türkiye

• Gülşah ÖZSOY, Assist. Prof. Dr. · Selcuk University, Faculty of Health Sciences, Department of Physiotherapy and Rehabilitation, Konya, Türkiye

• Yasemin GEDİKLİ ERTÜRK, MSc. in PT · Selcuk University, Faculty of Health Sciences, Department of Physiotherapy and Rehabilitation, Konya, Türkiye

• Selen GÜR ÖZMEN, Assoc. Prof. Dr. · Bahçeşehir University, Faculty of Health Sciences, Department of Physiotherapy and Rehabilitation, Istanbul, Türkiye

• Haluk GÜMÜŞ, Prof. Dr. · Selçuk University, Faculty of Medicine, Department of Neurology, Konya, Türkiye

• Tuğbanur BAYTOK, Dr. · Selçuk University, Faculty of Medicine, Department of Neurology, Konya, Türkiye

• Cahit AYAN, Dr. · Selçuk University, Faculty of Medicine, Department of Neurology, Konya, Türkiye

Eligibility

Min Age

18 Years

Sex

ALL

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-02-02

Primary Completion

2026-06-30

Completion

2026-07-30

Countries

• Turkey (Türkiye)

Study Locations