Determinants of Corticosteroid Insensitivity in Smokers With Asthma

University of Glasgow

Status: Completed

Conditions: Steroid Resistance; Asthma; Smoking; Corticosteroid Insensitivity

Treatments: Drug: oral steroid-dexamethasone

Study type: Interventional

Funder types: Other

Identifiers

NCT00411320

AR002

Details and patient eligibility

About

Smokers with asthma display a relative insensitivity to inhaled and oral corticosteroids. The causes of this phenomenon are currently unknown. The investigators will perform a number of blood & breathing tests to try to discover the cause/s behind this phenomenon with the aim of producing leads for further investigation and possible new treatments for smokers with asthma.

Full description

Smokers with asthma display a relative insensitivity to inhaled and oral corticosteroids. The causes of this phenomenon are currently unknown. However research into steroid resistance in severe asthma and the smoking related condition chronic obstructive pulmonary disease (COPD) points to a number of possible causes. We will characterise a group of smokers with asthma and perform a number of investigations and compare the results to ex-smokers and never smokers with asthma with the aim of establishing which previously published steroid resistance phenomena are related to the steroid resistance displayed by smokers with asthma. Results produced from this trial will provide hypothesis generating information leading to future pharmaceutical trials.

Enrollment: 53 patients

Sex: All

Ages: 18 to 60 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Asthma (defined by either reversibility to bronchodilator or methacholine testing)

• Asthma duration of 6 months or greater

• Stable asthma

• Age 18-60

• Treatment with inhaled corticosteroids

• Smoking history consistent with group

  • smokers with asthma: > or = 5 pack years and currently smoking more than 5 cigarettes per day
  • ex-smokers: smoking ceased > or = two years prior to recruitment, minimum 5 pack year history
  • non-smokers: no smoking history

Exclusion criteria

• Presence of medical condition likely to be exacerbated by treatment with oral corticosteroids
• Treatment with > 2000 mcg beclomethasone (or equivalent) per day
• Subject requires oral corticosteroids to maintain asthma control
• Subject requires oral theophylline to maintain asthma control
• Recent treatment with oral corticosteroids
• Pregnancy or subject planning to become pregnant

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Single Group Assignment

Masking: None (Open label)

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53 participants in 5 patient groups

Group 1

Active Comparator group

Description:

Smokers with asthma

Treatment:

Drug: oral steroid-dexamethasone

Group 2

Active Comparator group

Description:

Ex-smokers with asthma

Treatment:

Drug: oral steroid-dexamethasone

Group 3

Active Comparator group

Description:

Non-smokers with asthma

Treatment:

Drug: oral steroid-dexamethasone

Group 4

No Intervention group

Description:

Non smokers without asthma

Group 5

No Intervention group

Description:

Smokers without asthma or COPD