Respiratory Muscle Strength in Patients With Obesity Hypoventilation Syndrome (OHS) or With a Precursor of the Disease

Recruiting

• Conditions: Obesity Hypoventilation Syndrome
• Interventions: Diagnostic Test: magnetic phrenic nerve stimulation

• Registration Number: NCT03854058
• Lead Sponsor: Wissenschaftliches Institut Bethanien e.V

Brief Summary

Using an extensive set of both volitional and non-volitional tests of respiratory muscle function and strength it is the aim of this study to

* identify potential determinants for the development of obesity hypoventilation

* to identify predictors for the presence of a sleep-related hypoventilation requiring treatment in obese patients

Detailed Description

Not available

Study Timeline

• Study First Submitted: 2019-02-20
• Study First Submitted QC: 2019-02-21
• Study First Posted: 2019-02-26
• Study Start: 2019-05-01
• Status Verified: 2023-12
• Last Update Submitted: 2023-12-14
• Last Update Posted: 2023-12-15
• Primary Completion: 2024-12
• Study Completion: 2024-12

Recruitment & Eligibility

• Status: RECRUITING
• Sex: All
• Target Recruitment: 50

Inclusion Criteria

• patients with BMI > 30 and obesity-associated hypoventilation stages I - IV
• patients with BMI > 30 and elevated OHS-risk (= obstructive sleep apnea without hypercapnia)
• age:18-80 years
• capacity to consent

Exclusion Criteria

• any other disease, that causes ventilatory insufficiency
• pacemaker, defibrillators or device for deep brain or vagus nerve stimulation
• esophagitis, Barrett-esophagus, esophageal cancer
• acute gastritis and ulcera ventriculi
• epilepsy
• any medical, psychological or other condition impairing the patient's ability to provide informed consent

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
OHS or elevated OHS-risk (stages 0-IV)	magnetic phrenic nerve stimulation	stage 0: OHS-risk (OSA / no hypercapnia) stage I: obesity associated hypoventilation (intermittent hypercapnia during sleep, arterial carbon dioxide partial pressure (PaCO2) or transcutaneous carbon dioxide partial pressure (PtcCO2) morning \~ evening), bicarbonate \< 27 mmol/L awake) stage II: obesity associated hypoventilation (intermittent hypercapnia during sleep, PaCO2 or PtcCO2 morning \> evening, bicarbonate ≥ 27 mmol/L awake) stage III: OHS (hypercapnia, carbon dioxide partial pressure (PCO2) \> 45 mmHg awake) stage IV: OHS with end organ damage (hypercapnia , PCO2 \> 45 mmHg awake, cardiometabolic comorbidities) diagnostic tests: magnetic phrenic nerve stimulation, diaphragmatic ultrasound

Primary Outcome Measures

Name	Time	Method
transdiaphragmatic pressure (non-volitional)	1 day	difference between intraesophageal and intragastral pressure after posterior magnetic stimulation of the phrenic nerves
diaphragmal ultrasound - thickness (non-volitional)	1 day	thickness of the diaphragm
P0.1 (volitional)	1 day	mouth occlusion pressure (kPa)
peripheral nervous system (non-volitional)	1 day	electroneurography after posterior magnetic stimulation of the phrenic nerves
Carbon dioxide rebreathing test	1 day	minute volumen (L/min)
diaphragmal ultrasound - excursion (non-volitional)	1 day	excursion of the diaphragm
PImax (volitional)	1 day	maximal inspiratory mouth pressure (kPa)

Secondary Outcome Measures

Name	Time	Method
Comparison of PImax and transdiaphragmatic pressure	1 day	Correlation between PImax and transdiaphragmatic pressure

Trial Locations

Locations (1)

Institut für Pneumologie an der Universität zu Köln / Wissenschaftliches Institut Bethanien für Pneumologie e.V.; 🇩🇪 Solingen, Nordrhein-Westfalen, Germany