Respiratory and Peripheral Muscle Strength as Predictors of Inhaler Treatment Response in Asthma: A Comparison of DPI and MDI Devices

November 14, 2025 updated by: Bugra Kerget

Respiratory and Peripheral Muscle Strength as Predictors of Inhaler Treatment Response in Asthma: A Randomized Comparison of Dry Powder and Metered Dose Inhalers

Asthma is a chronic respiratory disease characterized by variable airway obstruction. Inhaled therapies are the cornerstone of asthma management, and selecting the appropriate inhaler device is essential for effective treatment. Among available devices, metered dose inhalers (MDIs) and dry powder inhalers (DPIs) are commonly used; however, their effectiveness depends not only on the medication but also on the patient's physiological capacity and inhalation technique.

This prospective randomized study aimed to evaluate the factors influencing inhaler treatment response in newly diagnosed asthma patients. A total of 80 patients with at least a high school education, who demonstrated perfect inhaler technique and adherence, were randomly assigned to MDI or DPI groups (n = 40 each). Baseline and one-month follow-up assessments included pulmonary function tests (PFTs), inspiratory and expiratory muscle strength measurements (MIP, MEP), Asthma Control Test (ACT), and handgrip strength (HGS).

The study investigated how respiratory and peripheral muscle strength, inspiratory capacity, coordination skills, and clinical status affect treatment outcomes with MDI and DPI. Findings from this research may help guide inhaler selection based on patient-specific physiological characteristics to optimize treatment effectiveness.

Study Overview

Status

Completed

Conditions

Intervention / Treatment

Study Type

Interventional

Enrollment (Actual)

80

Phase

  • Not Applicable

Contacts and Locations

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

Study Locations

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

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

Adults aged ≥ 18 years Newly diagnosed asthma according to GINA guidelines Education level of at least high school Ability to use inhaler devices correctly after standardized training Provided written informed consent to participate

Exclusion Criteria:

Presence of other chronic lung diseases (e.g., COPD, interstitial lung disease) Acute asthma exacerbation at the time of enrollment Severe neurological or cognitive impairment affecting inhaler use

Pregnancy or breastfeeding

Refusal or inability to provide informed consent

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

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: MDI Group
Participants receive inhaled therapy using metered-dose inhalers (MDIs) containing beclomethasone dipropionate 100 µg + formoterol fumarate 6 µg per actuation, 2 puffs twice daily for one month.
Drug: MDI Inhaler Therapy
Patients in the MDI group received Foster® metered-dose inhaler (MDI) containing beclomethasone dipropionate 100 µg + formoterol fumarate 6 µg per actuation, administered as two puffs twice daily for one month.
Experimental: DPI Group
Participants receive inhaled therapy using dry powder inhalers (DPIs) (Foster® Nexthaler) containing beclomethasone dipropionate 100 µg + formoterol fumarate 6 µg per inhalation, 2 inhalations twice daily for one month.
Drug: DPI Inhaler Therapy
Patients in the DPI group received Foster® Nexthaler dry powder inhaler (DPI) containing beclomethasone dipropionate 100 µg + formoterol fumarate 6 µg per inhalation, administered as two inhalations twice daily for one month.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in FEV₁ (%) from Baseline to 1 Month
Time Frame: Baseline and 1 month after treatment initiation
The primary outcome is the change in forced expiratory volume in one second (FEV₁) expressed as percent of predicted from baseline to one month after initiation of inhaler therapy. Pulmonary function tests were performed according to ATS/ERS 2019 guidelines using the same spirometry device for all participants.
Baseline and 1 month after treatment initiation

Collaborators and Investigators

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

Sponsor

Bugra Kerget

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)

March 1, 2025

Primary Completion (Actual)

September 24, 2025

Study Completion (Actual)

September 24, 2025

Study Registration Dates

First Submitted

November 14, 2025

First Submitted That Met QC Criteria

November 14, 2025

First Posted (Actual)

November 18, 2025

Study Record Updates

Last Update Posted (Actual)

November 18, 2025

Last Update Submitted That Met QC Criteria

November 14, 2025

Last Verified

November 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

  • B.30.2ATA.0.01.00/600

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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