Respiratory Muscle Endurance in Obesity Hypoventilation Syndrome

Respiratory Muscle Endurance in Obesity Hypoventilation Syndrome; Evaluation by Incremental Load Test

Obesity hypoventilation syndrome (OHS) is defined as a combination of obesity [body mass index (BMI) ≥30 kg/m2], chronic daytime hypercapnia (PaCO2 >45 mm Hg), and sleep-apnea in the absence of other known causes of hypercapnia. Respiratory system compliance decreases and resistance increases in OHS. This causes increase in work of breathing and oxygen cost of breathing, which may result in respiratory muscle fatigue. Increase in respiratory workload and increase in resistance to respiration is expected to decrease in respiratory muscle endurance (RME) in subjects with OHS.

Study Overview

• Status: Completed
• Conditions: Obesity Hypoventilation Syndrome (OHS)

Detailed Description

In the literature, studies evaluating RME in subjects with OHS are limited. No study has been found to evaluate RME using the incremental load test in subjects with OHS. Accordingly, it was aimed to evaluate and compare respiratory muscle endurance in subjects with OHS and a control group, and to determine factors associated with respiratory muscle endurance.

• Study Type: Observational
• Enrollment (Actual): 60

Contacts and Locations

Study Locations

• Turkey
  • Istanbul, Turkey
    • Istanbul University

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 24 years to 69 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

• Sampling Method: Probability Sample

Study Population

All subjects who had polysomnography performed in the sleep laboratory and were diagnosed with OHS were screened.

Age and sex-matched obese subjects (30 < body mass index < 40 kg/m2) with low risk of obstructive sleep apnea (STOP-BANG score < 3) included in the study as the control group.

Description

Inclusion Criteria:

• Diagnosed with OHS
• Obese subjects (30 < body mass index < 40 kg/m2) with low risk of obstructive sleep apnea (STOP-BANG score < 3)

Exclusion Criteria:

• Severe respiratory disease
• Subjects with orthopeadic and/or neurologic disorders that could limit exercise tests

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Control
• Time Perspectives: Prospective

Number of groups / cohorts

3

Cohorts and Interventions

Group / Cohort
Group I; Subjects with obesity hypoventilation sydrome (30 < body mass index < 40 kg/m2)
Group II; Subjects with obesity hypoventilation sydrome (body mass index > 40 kg/m2)
Control Group; Age and sex-matched obese subjects (30 < body mass index < 40 kg/m2) with low risk of obstructive sleep apnea (STOP-BANG score < 3)

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incremental load test	Respiratory muscle endurance was evaluated by incremental load test. The incremental load test was performed using the electronic inspiratory loading device (PowerBreathe®-KHP2).	1 day

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Mouth pressure measurements	Respiratory muscle strength was measured using mouth pressure measurements (Micro Medical MicroRPM).	1 day
6 minute walk test	The 6 minute walk test was used to evaluate the functional exercise capacity of the subjects.	1 day
Epworth Sleepiness Scale	Excessive daytime sleepiness was assessed with the Epworth Sleepiness Scale. A score of >10 accepted as daytime sleepiness.	1 day
Pittsburg Sleep Quality Index	Sleep quality was assessed with the Pittsburg Sleep Quality Index. The total score were interpreted as follows: 0-5 indicated good sleep quality, > 5 indicated poor sleep quality, and >10 indicated the presence of a sleep disorder.	1 day
Fatigue Severity Scale	Fatigue severity was assessed with the Fatigue Severity Scale. This seven-likert scale was used for each item and final score was accepted as mean value of the 9 items. The higher scores indicated higher fatigue severity.	1 day
EQ-5D Health-Related Quality of Life Questionnaire	Quality of life was assessed with the EQ-5D Health-Related Quality of Life Questionnaire. The maximum score of 1 indicates the best health state, and higher scores indicate more severe or frequent problems. In addition, there is a visual analogue scale (VAS) to indicate the general health status in which 100 indicates the best health status.	1 day
Obesity and Weight Loss Quality of Life Instrument	Quality of life specific to obesity was assessed with the Obesity and Weight Loss Quality of Life Instrument. As the total score from the scale approaches 0, the quality of life decreases, and as it approaches 100, the quality of life increases.	1 day

Collaborators and Investigators

• Sponsor: Istanbul University

Study record dates

Study Major Dates

• Study Start (Actual): February 5, 2018
• Primary Completion (Actual): November 5, 2018
• Study Completion (Actual): January 24, 2019

Study Registration Dates

• First Submitted: March 28, 2021
• First Submitted That Met QC Criteria: April 4, 2021
• First Posted (Actual): April 8, 2021

Study Record Updates

• Last Update Posted (Actual): April 8, 2021
• Last Update Submitted That Met QC Criteria: April 4, 2021
• Last Verified: April 1, 2021

More Information

Terms related to this study

• Keywords: Quality of Life; Fatigue; Sleep; Respiratory Muscle Endurance
• Additional Relevant MeSH Terms: Pathologic Processes; Nervous System Diseases; Respiratory Tract Diseases; Apnea; Respiration Disorders; Sleep Disorders, Intrinsic; Dyssomnias; Sleep Wake Disorders; Disease; Overnutrition; Nutrition Disorders; Overweight; Body Weight; Signs and Symptoms, Respiratory; Sleep Apnea Syndromes; Respiratory Insufficiency; Sleep Apnea, Obstructive; Syndrome; Obesity; Hypoventilation; Obesity Hypoventilation Syndrome
• Other Study ID Numbers: 29713

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No