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Factors Associated With Chronic Respiratory Failure in Obesity

The recruitment status of this study is unknown. The completion date has passed and the status has not been verified in more than two years.
Verified June 2011 by Oxford University Hospitals NHS Trust.
Recruitment status was:  Not yet recruiting
Information provided by:
Oxford University Hospitals NHS Trust Identifier:
First received: June 16, 2011
Last updated: July 7, 2011
Last verified: June 2011

Some overweight individuals develop problems with their breathing such that they gradually breathe less and less. This leads to a lack of oxygen and a buildup of carbon dioxide in the blood, called ventilatory failure. As a consequence, if such a person develops a chest infection, they are more likely to become seriously ill and need intensive care. In addition they are much more likely to develop severe complications during and following operations. This problem can be treated with a machine at home used overnight to help breathing. It is interesting that ventilatory failure only happens in some overweight individuals, and the investigators do not understand what factors make this complication develop. There are a number of theories: for example the distribution of the fat, additional lung disease (such as asthma), the addition of obstructive sleep apnoea, a condition when there are periods of cessation of breathing overnight (which is more common in obese individuals), weak muscles of breathing (perhaps due to fatty infiltration of muscles or vitamin D deficiency), and other hormonal changes.

The investigators intend to measure many potential factors in a range of overweight individuals, some who have ventilatory failure, and some who do not, to try and work out which are the important factors that cause this problem. If the investigators can identify such factors, then this will help predict in advance who is at risk from chest infections and during operations; thus allowing for earlier provision of an overnight breathing machine. This should reduce complications and potentially deaths in such individuals.

Obesity Hypoventilation Syndrome

Study Type: Observational
Study Design: Time Perspective: Cross-Sectional
Official Title: Factors Associated With Chronic Respiratory Failure in Obesity: A Cross-sectional Study

Resource links provided by NLM:

Further study details as provided by Oxford University Hospitals NHS Trust:

Primary Outcome Measures:
  • To determine the physiological between obese patients with OHS and obese patients without OHS [ Time Frame: 1 year ]
    This will be a detailed ventilatory drive measurements and muscle strength testing. The comparison will be made within the group amongst the range of ventilatory failure

Biospecimen Retention:   Samples With DNA
Blood, fat, muscle

Estimated Enrollment: 60
Study Start Date: June 2011
Estimated Study Completion Date: June 2012
Estimated Primary Completion Date: June 2012 (Final data collection date for primary outcome measure)
Study group
Obese BMI>30 18-85 years old

Detailed Description:
To test the hypothesis that in obese patients with obesity-hypoventilation (OHS) there are specific factors related to the development of ventilatory failure, compared to obese subjects not in ventilatory failure

Ages Eligible for Study:   18 Years to 85 Years   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No
Sampling Method:   Non-Probability Sample
Study Population

Obese (BMI > 30kg/m2) with or without OHS (18-85yrs)

  1. Admitted for management of OHS
  2. Attending the sleep and ventilation clinic
  3. Being assessed for bariatric surgery

Inclusion Criteria:

  • Obese (BMI > 30) with or without obesity hypoventilation
  • (OHS) (18 - 85yrs)
  • Admitted for management of their OHS
  • Attending the sleep and ventilation clinic
  • Being assessed for bariatric surgery
  • Willing and able to give informed consent for participation in the study
  • Men and women aged 18 - 85 years

Exclusion Criteria:

  • Respiratory acidosis pH <7.30
  • Severe untreated hypothyroidism
  • Current treatment with theophylline
  • Current treatment with diuretics
  • Severe restrictive or obstructive lung disease (<30% predicted)
  • Severe comorbidities such as moderate/severe COPD, left sided heart failure, and primary CNS or neuromuscular diseases
  • Contraindications to MRI scanning
  • Contraindications to DXA scanning
  • Previous participant in research in the last 12 months
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Please refer to this study by its identifier: NCT01380418

Contact: ARI MANUEL, MBBS BSC MRCP 01865741841

United Kingdom
Oxford Radcliffe NHS Trust Hospitals
Oxford, United Kingdom, OX3 7LJ
Sponsors and Collaborators
Oxford University Hospitals NHS Trust
Study Director: John Stradling, FRCP MBBS PHD University of Oxford
  More Information

Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: John Stradling, Oxford Radcliffe Hospitals NHS Trust Identifier: NCT01380418     History of Changes
Obsolete Identifiers: NCT01385462
Other Study ID Numbers: 11/H0605/9
Study First Received: June 16, 2011
Last Updated: July 7, 2011

Keywords provided by Oxford University Hospitals NHS Trust:

Additional relevant MeSH terms:
Respiratory Insufficiency
Obesity Hypoventilation Syndrome
Nutrition Disorders
Body Weight
Signs and Symptoms
Respiration Disorders
Respiratory Tract Diseases
Sleep Apnea, Obstructive
Sleep Apnea Syndromes
Sleep Disorders, Intrinsic
Sleep Wake Disorders
Nervous System Diseases
Signs and Symptoms, Respiratory processed this record on April 25, 2017