Smoking, respiratory symptoms and likely asthma in young people: evidence from postal questionnaire surveys in the Wythenshawe Community Asthma Project (WYCAP)

Abstract

BackgroundAlthough it is recognised that smoking is a major risk factor for subjects with chronic obstructive pulmonary disease and is associated with respiratory symptoms, there is less agreement concerning the relationship between asthma and smoking. This study aims to examine the relationship between cigarette smoking and asthma prevalence.MethodData were used from two postal questionnaire surveys (1999 and 2001) in two general practice populations, using a respiratory questionnaire based on the ECRHQ and a generic quality of life questionnaire (EQ-5D). Only subjects less than 45 years old were included in the survey. An empirical definition of likely asthma was used based on respiratory questionnaire responses. Smoking was examined according to three categories, current smoker, ex smoker and never smoker.ResultsAlmost 3500 subjects were included in the analyses. Current smokers had a higher prevalence of likely asthma compared to never smokers, odds ratio (OR) 1.59 (95% confidence interval (CI) 1.24 to 2.04). and also compared to ex smokers OR 1.79 (CI 1.25 to 2.56), but there was no difference between ex smokers and never smokers (OR 1.00 (0.75–1.35)). Current smoking was also positively associated with all symptoms but not with a history of hayfever/eczema.ConclusionAlthough the positive association found between current smoking and obstructive airways disease is likely to be due to the effect of cigarettes on asthma, it could reflect an association with early COPD (GOLD stages 0 or 1). Smoking cessation has a beneficial effect on the prevalence of respiratory symptoms and is therefore of paramount importance among these young adults.

Association between modelled traffic-related air pollution and asthma score in the ECRHS

“…Nevertheless, our estimates for well-known risk factors of asthma symptoms, such as smoking and a family history of asthma or atopy, are in the same range as those described in the literature. In a study among young adults, the odds ratio for asthma-like symptoms varied from 1.74 (shortness of breath) to 3 (wheezing) for smoking [28]. In a study conducted in Northern Europe, the odds ratio of presenting wheezing in the last 12 months ranged from 1.5-3.6 depending on the intensity of smoking.…”

Impact of smoking on asthma symptoms, healthcare resource use, and quality of life outcomes in adults with persistent asthma

“…Data are scarce regarding airway pathology in asthmatic patients who smoke, and results from community studies provide inconsistent results [25]. Studies have shown that the combination of smoking and asthma negatively affect lung functionality and inflammation to a greater degree than either factor alone [1,5,19,24].…”

Effect of active smoking and second-hand smoke on asthma of young people: community health survey

“…There appeared to be an increased prevalence of asthma according to smoking and second-hand smoke exposure [8,9]. Among the factors was the major variable of exposure to smoking in childhood, which relates to direct and indirect smoking.…”

“…In fact, about 1.9 million people die annually from these diseases. Recently, the effects of secondhand smoking on children and adolescents with asthma has attracted a great deal of research attention [8][9][10][11][12]. Asthma is more frequent in children and adolescents than adults, and it can be dangerous when asthma occurs in a susceptible group of people.…”