Symptom control among asthmatics with a clinically significant smoking history: a cross-sectional study in Finland.

BACKGROUND: Surprisingly little is known about asthma control among asthmatics who smoke. The aim of this cross-sectional study was to investigate asthma symptom control according to the GINA guidelines among asthmatics with a clinically significant smoking history. METHODS: One hundred ninety asthmatics from primary care in Finland were investigated. The patients were current or previous cigarette smokers with a history of 10 or more pack-years. They completed a questionnaire including questions on asthma symptoms and reliever use so that their level of asthma symptom control (well controlled, partly controlled, or uncontrolled) according to GINA could be determined. RESULTS: Sixty-six (34.7%) patients had their asthma well controlled, 81 (42.6%) had their asthma partly controlled, and 43 (22.6%) had uncontrolled asthma. Current smokers had uncontrolled asthma more often than ex-smokers, OR 2.54 (95% CI 1.25-5.14, p = 0.01). Patients with moderate to severe asthma exacerbation during the previous year had uncontrolled asthma more often than patients without an exacerbation, OR 2.17 (95% CI 1.06-4.47, p = 0.04), and patients with FEV1 <  80% of predicted had uncontrolled asthma more often than patients with FEV1 > 80% of predicted, OR 2.04 (95% CI 1.02-4.08, p = 0.04). CONCLUSIONS: Asthmatic patients with a clinically significant smoking history often do not have well controlled asthma. Poor asthma symptom control was associated with current smoking status, history of exacerbations and impaired lung function. Therefore, every attempt should be made to help asthmatics who smoke to quit smoking.

Prevalence of asthma-COPD overlap syndrome among primary care asthmatics with a smoking history: a cross-sectional study.

BACKGROUND: The overlap between asthma and chronic obstructive pulmonary disease (COPD) is an important clinical phenomenon. However, the prevalence of asthma-COPD overlap syndrome (ACOS) is not known. AIMS: To investigate the prevalence of ACOS among asthmatic patients with a smoking history, and evaluate the factors predicting ACOS in this patient group. METHODS: We investigated 190 primary care asthma patients with no previous diagnosis of COPD, but who were either current or ex-smokers, with a smoking history of at least 10 pack-years. Spirometry was performed on all the patients while they were taking their normal asthma medication. Patients were considered to have ACOS if their postbronchodilator forced expiratory volume in 1 s/forced vital capacity was < 0.70. RESULTS: Fifty-two (27.4%) of the patients were found to have ACOS. Age ⩾ 60 years and smoking for ⩾ 20 pack-years were the best predictors of ACOS. If both of these criteria were met, the odds ratio (95% confidence interval) for ACOS was 6.08 (2.11-17.49), compared with the situation where neither of these criteria were fulfilled. CONCLUSIONS: There is a high prevalence of ACOS among primary health care asthmatics with a positive smoking history but no previous diagnosis of COPD. In this population, age over 60 years and a smoking history of more than 20 pack-years were the best predictors of ACOS.