Perret, JL and Dharmage, SC and Matheson, MC and Johns, DP and Gurrin, LC and Burgess, JA and Marrone, J and Markos, J and Morrison, S and Feather, I and Thomas, PS and McDonald, CF and Giles, GG and Hopper, JL and Wood-Baker, R and Abramson, MJ and Walters, EH, The interplay between the effects of lifetime asthma, smoking, and atopy on fixed airflow obstruction in middle age, American Journal of Respiratory and Critical Care Medicine, 187, (1) pp. 42-48. ISSN 1073-449X (2013) [Refereed Article]
Copyright 2013 by the American Thoracic Society
Rationale: The contribution by asthma to the development of fixed airflow obstruction (AO) and the nature of its effect combined with active smoking and atopy remain unclear.
Objective: To investigate the prevalence and relative influence of lifetime asthma, active smoking, and atopy on fixed AO in middle age.
Methods: The population-based Tasmanian Longitudinal Health Study cohort born in 1961 (n = 8,583) and studied with prebronchodilator spirometry in 1968 was retraced (n = 7,312) and resurveyed (n = 5,729 responses) from 2002 to 2005. A sample enriched for asthma and chronic bronchitis underwent a further questionnaire, pre- and post-bronchodilator spirometry (n = 1,389), skin prick testing, lung volumes, and diffusing capacity measurements. Prevalence estimates were reweighted for sampling fractions. Multiple linear and logistic regression were used to assess the relevant associations.
Measurement and Main Results: Main effects and interactions between lifetime asthma, active smoking, and atopy as they relate to fixed AO were measured. The prevalence of fixed AO was 6.0% (95% confidence interval [CI], 4.5-7.5%). Its association with early-onset current clinical asthma was equivalent to a 33 pack-year history of smoking (odds ratio, 3.7; 95% CI, 1.5-9.3; P = 0.005), compared with a 24 pack-year history for late-onset current clinical asthma (odds ratio, 2.6; 95% CI, 1.03-6.5; P = 0.042). An interaction (multiplicative effect) was present between asthma and active smoking as it relates to the ratio of post-bronchodilator FEV1/FVC, but only among those with atopic sensitization.
Conclusions: Active smoking and current clinical asthma both contribute substantially to fixed AO in middle age, especially among those with atopy. The interaction between these factors provides another compelling reason for atopic individuals with current asthma who smoke to quit.
|Item Type:||Refereed Article|
|Keywords:||chronic obstructive pulmonary disease, COPD, fixed airflow obstruction, lifetime asthma, active smoking, atopy, interaction|
|Research Division:||Medical and Health Sciences|
|Research Group:||Cardiorespiratory Medicine and Haematology|
|Research Field:||Respiratory Diseases|
|Objective Group:||Clinical Health (Organs, Diseases and Abnormal Conditions)|
|Objective Field:||Respiratory System and Diseases (incl. Asthma)|
|Author:||Johns, DP (Associate Professor David Johns)|
|Author:||Marrone, J (Dr John Marrone)|
|Author:||Wood-Baker, R (Professor Richard Wood-Baker)|
|Author:||Walters, EH (Professor Haydn Walters)|
|Web of Science® Times Cited:||64|
|Deposited By:||Medicine (Discipline)|
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