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Trial registered on ANZCTR


Registration number
ACTRN12606000455561
Ethics application status
Not yet submitted
Date submitted
20/10/2006
Date registered
27/10/2006
Date last updated
27/10/2006
Type of registration
Prospectively registered

Titles & IDs
Public title
Does overweight change the pattern of lung function during the airway narrowing of asthma?
Scientific title
Is there a difference in lung function during bronchial challenge testing between obese and non-obese subjects with asthma?
Universal Trial Number (UTN)
Trial acronym
the INCA study
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Asthma 1429 0
Obesity 1430 0
Condition category
Condition code
Respiratory 1525 1525 0 0
Asthma
Diet and Nutrition 1526 1526 0 0
Obesity

Intervention/exposure
Study type
Observational
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
By testing individuals during broncho-constriction induced by airway challenge testing, we will measure lung function parameters to investigate whether obese asthmatics demonstrate the same spirometric picture compared to non-obese asthmatics. The measurements will be conducted at the begining of the challenge test, during and after bronchoconstriction has been achieved. The provocation test usually lasts half an hour and the lung function testing takes 15 mins at the beginning and end.
Intervention code [1] 1415 0
Diagnosis / Prognosis
Comparator / control treatment
No comparator.
Control group

Outcomes
Primary outcome [1] 2107 0
Changes in forced expiratory volume in one second (FEV1) during acute bronchoconstriction in obese and non-obese groups
Timepoint [1] 2107 0
Measured at the begining and end of bronchial challenge testing.
Primary outcome [2] 2108 0
Forced vital capacity (FVC) during acute bronchoconstriction in obese and non-obese groups
Timepoint [2] 2108 0
Measured at the begining and end of bronchial challenge testing.
Secondary outcome [1] 3649 0
Differences in FEV1 and FVC between obese and non-obese groups after bronchial challenge testing.
Timepoint [1] 3649 0

Eligibility
Key inclusion criteria
A previous diagnosis of asthma (according to ATS criteria) and a positive methacholine challenge (PD20 <8 micromol if on not on corticosteroid inhalers and PD¬20 < 12 micromol if on corticosteroid inhalers).
Minimum age
18 Years
Maximum age
65 Years
Gender
Females
Can healthy volunteers participate?
No
Key exclusion criteria
Pregnancy, males, smokers or ex-smokers (less than 10 pack year history and no cigarettes for in the last year), patients on oral corticosteroids, any patient with cardiac or neurological co-morbidity, any patient who has had a respiratory tract infection in the previous 6 weeks and for safety reasons, FEV1 less than 60% predicted or less than 1.5 litres at baseline, when stable.

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 outside Australia
Country [1] 412 0
New Zealand
State/province [1] 412 0

Funding & Sponsors
Funding source category [1] 1664 0
Self funded/Unfunded
Name [1] 1664 0
Respiratory Research Unit, Department of Medical and Surgical Sciences, University of Otago
Address [1] 1664 0
Country [1] 1664 0
New Zealand
Primary sponsor type
Individual
Name
Professor Robin Taylor, principle investigator, Respiratory Research Unit, Department of Medical and Surgical Sciences, University of Otago, Dunedin New Zealand
Address
Country
New Zealand
Secondary sponsor category [1] 1468 0
None
Name [1] 1468 0
none
Address [1] 1468 0
Country [1] 1468 0

Ethics approval
Ethics application status
Not yet submitted
Ethics committee name [1] 3106 0
Lower south regional ethics committee
Ethics committee address [1] 3106 0
Ethics committee country [1] 3106 0
New Zealand
Date submitted for ethics approval [1] 3106 0
Approval date [1] 3106 0
Ethics approval number [1] 3106 0

Summary
Brief summary
The hypothesis is that the airway narrowing of acute asthma is different depending on whether an individual is obese or non-obese. If this hypothesis is proven or refuted, it will help to aid doctors in acurately interpreting respiratory function tests.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 27349 0
Address 27349 0
Country 27349 0
Phone 27349 0
Fax 27349 0
Email 27349 0
Contact person for public queries
Name 10604 0
Dr Tim Sutherland
Address 10604 0
Respiratory Research Unit
Deartment of Medical and Surgical Sciences
University of Otago
Dunedin
Country 10604 0
New Zealand
Phone 10604 0
+64 3 4740999 ext. 8785
Fax 10604 0
Email 10604 0
tim.sutherland@stonebow.otago.ac.nz
Contact person for scientific queries
Name 1532 0
Professor Robin Taylor
Address 1532 0
Respiratory Research Unit
Deartment of Medical and Surgical Sciences
University of Otago
Dunedin
Country 1532 0
New Zealand
Phone 1532 0
+64 3 4740999 ext. 8785
Fax 1532 0
Email 1532 0
robin.taylor@stonebow.otago.ac.nz

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