Article

Effects of smoking cessation on lung function and airway inflammation in smokers with asthma.

FRCP, Department of Respiratory Medicine, Division of Immunology, Infection and Inflammation, University of Glasgow and Western Infirmary, Glasgow G11 6NT, UK.
American Journal of Respiratory and Critical Care Medicine (Impact Factor: 11.99). 08/2006; 174(2):127-33. DOI: 10.1164/rccm.200510-1589OC
Source: PubMed

ABSTRACT Active smoking in asthma is associated with worsening of symptoms, accelerated decline in lung function, and impaired response to corticosteroids.
To examine the short-term effects of smoking cessation on lung function, airway inflammation, and corticosteroid responsiveness in smokers with asthma.
Smokers with asthma were given the option to quit or continue smoking. Both groups underwent spirometry and induced sputum at baseline and at 1, 3, and 6 wk. Cutaneous vasoconstrictor response to topical beclometasone, airway response to oral prednisolone, and sensitivity of peripheral blood lymphocytes to corticosteroids were measured before smoking cessation and at 6 wk.
Of 32 subjects recruited, 11 opted to continue smoking (smoking control group). Of 21 subjects who opted for smoking cessation, 10 quit smoking for 6 wk (quit group). In the comparison of quitters with smokers at 6 wk, the mean (confidence interval [CI]) difference in FEV(1) was 407 ml (21, 793), p = 0.040, and the proportion of sputum neutrophils was reduced by 29 (51, 8), p = 0.039. Total cutaneous vasoconstrictor response score to topical beclometasone improved after smoking cessation with a mean (CI) difference of 3.56 (0.84, 6.28), p = 0.042, between quitters and smokers. There was no change in airway corticosteroid responses after smoking cessation.
By 6 wk after smoking cessation, subjects who quit smoking had achieved considerable improvement in lung function and a fall in sputum neutrophil count compared with subjects who continued to smoke. These findings highlight the importance of smoking cessation in asthma.

1 Bookmark
 · 
216 Views
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A subset of severe asthma patients has fixed airways obstruction, which is characterized by incomplete reversibility to bronchodilator challenge. We aimed to elucidate the factors associated with fixed airways obstruction in a cohort of patients with severe asthma in Singapore. 245 patients from the Singapore General Hospital-Severe Asthma Phenotype Study (SGH-SAPS) were screened. These patients fulfilled World Health Organization criteria for "treatment-resistant severe asthma" and were all on combination of high-dose inhaled corticosteroids and long-acting beta2 agonists. 76 patients had pre- and postbronchodilator lung function tests and were selected for analysis. They were divided into two groups based on postbronchodilator forced expiratory volume in one second, PostBDFEV1 % predicted: >=70% (Non-Fixed Obs) and < 70% (Fixed Obs). We compared clinical and demographic parameters between the two groups. Patients in the Fixed Obs group were more frequently past or current smokers and had a higher pack-year smoking history. Overall, pack-year smoking history had a modest negative correlation with PostBDFEV1 % predicted. Atopy, allergen sensitization (type and numbers), comorbidities, symptoms, health care utilization and medication use did not differ between the two groups. The prebronchodilator FEV1 % predicted, FEV1/FVC and FVC % predicted were significantly lower in the Fixed Obs group. In addition, prebronchodilator FVC % predicted accounted for more variability than FEV1/FVC in predicting PostBDFEV1. Smoking is associated with fixed airways obstruction in patients with treatment-resistant severe asthma in Singapore. Furthermore, our results suggest that both small and large airways obstruction contribute independently to fixed airways obstruction in severe asthma.
    BMC Pulmonary Medicine 12/2014; 14(1):191. DOI:10.1186/1471-2466-14-191 · 2.49 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Smoking has detrimental effects on asthma symptom control and response to treatment and is prevalent among asthma patients in South Korea. The aim of this study is to determine the prevalence of smoking among asthma patients in South Korea and to compare the medication regimens of asthma patients who do and do not smoke. A cross-sectional survey was conducted from August 2010 to January 2011. Participating physicians (N=25) recorded demographic and clinical data on all asthma patients presenting during the study period (N=2,032), and then recruited a subset of patients (N=500) for the survey such that half were self-reported current smokers. Recruited patients were between the ages of 18 and 60. Among presenting asthma patients, 17.3% were current smokers, 19.2% were former smokers, and 63.5% had never smoked. Within the analyzable study population (N=471), 212 patients reported smoking currently, 79 smoking formerly, and 180 never smoking. Among current and former smokers, 79.7% and 81.0%, respectively, were men, while women represented 80.5% of patients who had never smoked. Agreement was strong between physician-determined smoking status and patient-reported smoking status (κ=0.82; P<0.001). However, asthma medication regimens examined according to GINA treatment steps did not differ by smoking status. In addition, mean quality of life scores and level of asthma control did not differ by smoking status. In South Korea, physicians are well aware of the smoking status of their patients. However, smoking status did not affect the prescribed medication regimens of this population of asthma patients.
    Allergy, asthma & immunology research 01/2015; 7(1):30-6. DOI:10.4168/aair.2015.7.1.30 · 3.08 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: Tobacco smoking is a risk factor for chronic respiratory disorders. Tobacco epidemic is driven by adolescents and young adults. Tobacco-related morbidity rises with increasing years of smoking and increasing number of young smokers may have considerable future public health implications. Objective: This study investigated the effect of tobacco smoking on pulmonary function indices among undergraduates. Method: Cross sectional study involving 104 male undergraduates, between 18 and 30 years. They were recruited by snowball sampling and grouped based on their smoking status (current smoker 52: non-smoker 52). Participants with signs of respiratory disease or thoracic spine deformity or contraindication to spirometry were excluded from the study. Participants’ forced vital capacity (FVC), forced expiratory volume in first second (FEV1) both in litres and forced expiratory ratio (FER) in percentage were assessed using standard protocols. Data were analyzed using mean, standard deviation, independent t-test and chi-square test with alpha level set at 0.05. Results: The two groups were not significantly different in age, height and body mass index. Smokers had significantly reduced FVC (3.42±0.42 vs 3.87±0.4 litres) p=0.03; FEV1 (2.39±0.37 vs 3.22±0.38 litres) p=0.001 and FER (%) (70.7±7.58vs82.3±4.05) p=0.01. Among the smokers a relationship was observed between years and numbers of cigarette smoked and lung function. Proportion of participants with FER below the age-matched reference was significantly higher among smokers than non-smokers (40.4%vs6.7%) at p=0.021. Conclusion: Smoking reduced pulmonary function among undergraduates. This may have important public health implications as continued smoking may accelerate lung function deterioration and consequently increase future risk of developing lung disease.

Full-text (2 Sources)

Download
240 Downloads
Available from
Dec 17, 2014