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Trial registered on ANZCTR


Registration number
ACTRN12610000226000
Ethics application status
Approved
Date submitted
15/03/2010
Date registered
18/03/2010
Date last updated
18/03/2010
Type of registration
Prospectively registered

Titles & IDs
Public title
Pulmonary physiology in obesity
Scientific title
Physiological mechanisms behind the association between asthma and obesity - an observational study measuring airway closure
Secondary ID [1] 1506 0
None
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Asthma 256972 0
Condition category
Condition code
Respiratory 257116 257116 0 0
Asthma
Diet and Nutrition 257139 257139 0 0
Obesity

Intervention/exposure
Study type
Observational
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
Airway closure as measured by Single Photon Emission Computed Tomography (SPECT) and Computed Tomography (CT) scans scans and closing capacity will be measured. The other tests which will be measured are ventilation heterogeneity and lung volumes.
Patients will be seen for two visits, two days apart and recruitment will take place over the next three years.
Intervention code [1] 256149 0
Not applicable
Comparator / control treatment
No control.
Control group
Uncontrolled

Outcomes
Primary outcome [1] 258011 0
Airway closure - measured by SPECT/CT scans and single breath nitrogen washout tests.
Timepoint [1] 258011 0
measured once only following clinical assessment for all participants
Secondary outcome [1] 263575 0
Nil
Timepoint [1] 263575 0
Nil

Eligibility
Key inclusion criteria
Obesity, body mass index (BMI) > 30 kg/m2
Asthmatics with doctor diagnosed asthma
Minimum age
18 Years
Maximum age
80 Years
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
history of cardiac or respiratory disease,(other than asthma) current (within the last 6 months) or previous smoking >10 pack years

Study design
Purpose
Natural history
Duration
Cross-sectional
Selection
Defined population
Timing
Prospective
Statistical methods / analysis

Recruitment
Recruitment status
Not yet recruiting
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)

Funding & Sponsors
Funding source category [1] 256654 0
Charities/Societies/Foundations
Name [1] 256654 0
Woolcock Institute of Medical Research
Address [1] 256654 0
Po Box M77
Missenden Road PO
Camperdown
NSW 2050
Country [1] 256654 0
Australia
Primary sponsor type
Charities/Societies/Foundations
Name
Woolcock Institute of Medical Research
Address
Po Box M77
Missenden Road PO
Camperdown
NSW 2050
Country
Australia
Secondary sponsor category [1] 255942 0
Hospital
Name [1] 255942 0
Department of Respiratory Medicine
Address [1] 255942 0
Level 8, Royal North Shore Hospital,
Pacific Hwy, St Leonards,
NSW, 2065
Country [1] 255942 0
Australia

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 258676 0
Northern Sydney Health Human Research Ethics Committee (Hawkesbury)
Ethics committee address [1] 258676 0
Level 2, Building 51,
Royal North Shore Hospital,
Pacific Hwy, St Leonards,
NSW, 2065
Ethics committee country [1] 258676 0
Australia
Date submitted for ethics approval [1] 258676 0
28/10/2009
Approval date [1] 258676 0
Ethics approval number [1] 258676 0
0912-345M

Summary
Brief summary
There is an association between obesity and asthma. Obesity is thought to increase the risk of developing asthma and also the severity of asthma. The mechanisms behind this association are unclear. The aim of this study is to determine the of obesity on the pattern of ventilation (termed heterogeneity) and of airway closure. We propose that obesity increases closure of airways but improves ventilation patterns, thereby paradoxically protecting against asthmatic airway narrowing (airway hyperresponsiveness).
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 30939 0
Address 30939 0
Country 30939 0
Phone 30939 0
Fax 30939 0
Email 30939 0
Contact person for public queries
Name 14186 0
Dr Greg King
Address 14186 0
PO Box M77,
Missenden Road PO,
Camperdown
NSW, 2050
Country 14186 0
Australia
Phone 14186 0
+61 2 9926 6265
Fax 14186 0
+61 2 9114 0014
Email 14186 0
ggk@woolcock.org.au
Contact person for scientific queries
Name 5114 0
Dr Greg King
Address 5114 0
PO Box M77,
Missenden Road PO,
Camperdown
NSW, 2050
Country 5114 0
Australia
Phone 5114 0
+61 2 9926 6265
Fax 5114 0
+61 2 9114 0014
Email 5114 0
ggk@woolcock.org.au

No information has been provided regarding IPD availability
Summary results
No Results