Interactions between Cigarette Smoking and the Natural History of Idiopathic Pulmonary Fibrosis: Results (Part 3)
Cigarette Smoking, BAL Cell Populations and Prednisolone Therapy Response
Nonsmokers had a better response to prednisolone when evaluated for the difference (A) of TLC, Pa02 at rest and Dsb before and after four to eight weeks of treatment (Table 1). In contrast, no benefit was observed after prednisolone therapy in most of smokers and even worsening of PFT values occurred in view of these smoking patients. When the ATLC, APaOz and ADsb are plotted according to either the percentage or number of lymphocytes, there is a clear correlation between the intensity of the beneficial response to prednisolone therapy and the magnitude of the alveolar lymphocyte cell population (Fig 3). It is worthy of note that dyspnea duration was another predictive parameter of the prednisolone response (ie> ATLC and dyspnea duration were significantly correlated, rs = 0.62, p<0.01). Buy Asthma Inhalers Online
Cigarette Smoking and Survival
At the time of data analysis (June, 1989), 16 patients were dead either by respiratory insufficiency (n = 15) or lung carcinoma (n = l). Survival curves demonstrated similar death rates in both groups.
Male-Female Differences in IPF
The comparison between male and female patients showed a predominance of smokers among males (9 of 14) and of nonsmokers among females (11 of 13), consequently when comparing males with females similar distinctive features were observed (not shown) than when comparing smokers with nonsmokers. No comparative study between males and females within the smokers* group could be achieved because of the small number of females with smoking habits (n = 2). However, we did not observe any male-female difference among nonsmokers either in the clinical status, PFTs at the time of presentation, short-term glucocorticoid responsiveness (Table 1), or in alveolar cell populations collected by BAL. It is noteworthy that when the male population was studied apart, the smoker-nonsmoker comparison displayed similar distinctive features than in the whole study population with a significantly shorter time of dyspnea duration before IPF recognition and a higher prednisolone responsiveness in nonsmokers (significant for changes observed in TLC and Pa02, Table 1).
Figure 3. Relationship of short-term steroid responsiveness and BAL lymphocyte counts. Steroid responsiveness is assessed by PFT changes: ATLC percent (top), APaOa at rest mm Hg (center), ADsb percent (bottom) and the BAL lymphocyte counts were expressed as the percentage (left) or absolute number per milliliter (right). Open squares, nonsmokers; solid squares, smokers.