Interactions between Cigarette Smoking and the Natural History of Idiopathic Pulmonary Fibrosis: Discussion (Part 4)
That cigarette smoke interacts with those features was not previously reported. Our study differs from a previous observation relating similar rate of prednisolone benefit in smokers and nonsmokers but a higher duration of exertional dyspnea before therapy and a different rate of smoking habits in the reported patients could explain this discrepancy.
Smoking Habits and Survival
Despite the initial corticosteroid efficiency in nonsmokers, the overall prognosis of IPF as assessed by survival time was similar in nonsmokers and in smokers as already shown by Turner-Warwick and coworkers.
Our population study confirms that there are some male-female differences in the course of IPF. However, our data argue against the hypothesis that this gender difference accounts, per se, for such a discrepancy and suggests that it is mainly related to differences in smoking habits. So the better results of treatment previously observed among women should be reevaluated taking into account the detailed smoking history of the patients.
In conclusion, the clinical variant of IPF characterized by a subacute onset, a high intraalveolar lymphocyte population evaluated by BAL analysis and a better response to prednisolone therapy is mainly observed in the absence of smoking habits. The biologic impacts of cigarette smoke in IPF cannot be definitively extrapolated from this clinical study and need further studies particularly concerning the cigarette smoking and T cell blastogenesis. levitra super active plus