Long-term smoking increases the need for acute care among asthma patients: A case control study

Abstract

Background: To examine risk factors for asthma patients' emergency room (ER) visits in a well organized asthma care setting.Methods: A random sample of 344 asthma patients from a Pulmonary Clinic of a University Hospital were followed through medical records from 1995 to 2006. All the ER visits due to dyspnea, respiratory infections, chest pain, and discomfort were evaluated.Results: The mean age of the study population was 56 years (SD 13 years), 72% being women. 117 (34%) of the patients had had at least one ER visit during the follow-up (mean 0.5 emergency visits per patient year, range 0-7). Asthma exacerbation, lower and upper respiratory infections accounted for the 71% of the ER visits and 77% of the hospitalizations. The patients with ER visits were older, had suffered longer from asthma and more frequently from chronic sinusitis, were more often ex- or current smokers, and had lower lung function parameters compared to the patients without emergency visits. Previous (HR 1.9, CI 1.3-3.1) and current smoking (HR 3.6, CI 1.6-8.2), poor self-reported health related quality of life (HRQoL) (HR 2.5, CI 1.5-4), and poor lung function (FEV1 < 65%, HR 2.2, CI 1.3-3.7) remained independent risk factors for ER visits after adjustment for age and gender.Conclusions: Asthma patients who are or have been long-term smokers are more likely to require ER care compared to never smokers. © 2014 Kauppi et al.; licensee BioMed Central Ltd.