NCT07598292Completed
Predicting Dynamic Inspiratory Muscle Strength in COPD and Asthma Patients
Prediction Models for Dynamic Respiratory Muscle Strength in COPD and Asthma Patients Based on Constant-Pressure Inspiratory Muscle Performance
Source: ClinicalTrials.gov · Last updated 20 May 2026
Brief summary (registry, in English)
This observational study evaluates whether dynamic inspiratory muscle strength can be estimated in patients with chronic obstructive pulmonary disease (COPD) and asthma using simple clinical and performance-based measurements. Dynamic inspiratory muscle strength was assessed using the S-Index, which reflects the pressure generated during a fast and forceful inspiration while airflow is maintained. The study included adult male patients diagnosed with COPD or asthma. Participants completed respiratory muscle strength assessment, pulmonary function testing, body composition assessment, and a fixed-pressure inspiratory muscle performance test using a threshold loading device set at 30 cmH₂O. The number of inspiratory repetitions performed until task failure and related respiratory variables were recorded. The main aim of the study was to develop prediction models for estimating S-Index values from accessible measures such as peak inspiratory flow, inspiratory repetition performance, spirometry parameters, and body composition variables. The study may help determine whether dynamic inspiratory muscle strength can be estimated in clinical settings where direct S-Index measurement devices are not available.
- Status (registry)
- Completed
- Study type
- Observational
- Enrollment
- 123 (actual)
- First submitted
- 7 May 2026
- Start date
- Feb 2026
- Primary completion date
- Mar 2026
- Lead sponsor
- Hitit University
- NCT number
- NCT07598292
What you commit to
- Study type: Observational
- Participants enrolled: 123
- From Feb 2026 to the primary completion date, Mar 2026
- 1 site in 1 country
- Visits and tests: ask the trial team, the registry does not list them
Built from the registry fields of ClinicalTrials.gov. It describes the study, not your situation.
Who cannot take part
Copied verbatim from ClinicalTrials.gov and grouped by topic. Only the trial team decides who can take part.
Prior treatment
- Presence of a musculoskeletal injury or surgical history affecting the diaphragm, thorax, spine, or abdominal region that could significantly impair respiratory mechanics
Other illness
- Presence of neurological conditions that may affect respiratory muscle function, such as neuromuscular diseases, peripheral nerve damage, or central nervous system disorders
Other
- Smoking
- Inability to perform fixed-pressure inspiratory muscle loading or dynamic respiratory muscle strength assessment according to the technical requirements of the measurement protocols
- Inability to obtain reliable data due to insufficient coordination, motivation, or volitional effort
Who the study is looking for
- Being 18 years of age or older
- Having a clinical diagnosis of chronic obstructive pulmonary disease or asthma
- Being able to perform fixed-pressure inspiratory muscle loading and S-Index measurements in accordance with the instructions and with correct technique
- Having experienced no additional clinical condition within the previous 12 weeks, apart from the existing chronic respiratory disease, that could acutely affect respiratory function
- Having signed the informed consent form approved by the ethics committee
Age in the registry: 18 years to - · Sex: Male · Does not accept healthy volunteers
Sites (1)
Sites in registry order. Pick your city on the disease page to sort them by distance.
| Site | City | Country | Site status |
|---|---|---|---|
| Hitit University Çorum Erol Olçok Training and Research Hospital Coordinator of this site? Confirm its status | Çorum | Turkey (Türkiye) | Unknown status |
This page is information, not medical advice. Discuss any trial with your doctor.