The Science Journal of the American Association for Respiratory Care

2011 OPEN FORUM Abstracts


Sylvia Njau, David Chang; University of South Alabama, Mobile, AL

Background: Cigarette smoking has an inflammatory effect on the lungs causing the release of white blood cells (WBC) in the body. Studies have shown an elevated level of leukocytes in the sputum and blood in smokers. This study was done to evaluate the relationship between smoking history and leukocyte count of a patient population in a city in the southeastern U.S. Method: Institutional IRB approval was obtained before implementation of the study. Forty sequential inpatients over 18 years old were recruited for this study. The inclusion criterion is verified physician orders on sputum analysis via bronchoscopic or induced sputum samples. The data on smoking history of these patients were collected by personal interview. They were asked how long they had been smoking and how many packs they smoked a day. The medical records of these patients were accessed to obtain the results of the laboratory test on the number of WBC found in the bronchoscopy or induced sputum samples. The smoking history by pack-year and WBC count were recorded on a data collection form. Pearson correlation and linear regression (StatPac software) were used to evaluate the relationship between smoking history and sputum WBC count. Results: The smoking history of the 40 patients ranged from 0 to 305 pack-years. The WBC count of the sputum sample showed a weak linear relationship (r2 = 0.1312) between the smoking history and increase of WBC count in the sputum (see figure). Conclusions: Based on the population of patients in this study, a weak correlation was found between the number of pack-year a patient smoked and the number of white blood cells found in the sputum. Future related studies should take the following factors into account in the methodology: larger sample size, sputum collection techniques, recent use of antibiotics, chronic pulmonary infections, and history of asthma. Sponsored Research - None Linear regression of smoking history and WBC count