[A retrospective cohort study of prognostic factors for death in patients with idiopathic pulmonary fibrosis].

Objective: To investigate the prognostic implications of clinical, radiographic, and physiological variables in idiopathic pulmonary fibrosis (IPF).

Methods: The clinical, pulmonary physiological, bronchoalveolar lavage fluid (BALF) cell differentials and lung high-resolution computed tomography (HRCT) at diagnosis in 126 patients with IPF were retrospectively analyzed. Univariate and multivariate Cox proportional-hazards regression analysis was used to evaluate various parameters associated with hazard ratio (HR). The survival rates of all groups were compared using the Kaplan-Meier method.

Results: In 29.6 months of average follow-up time, the survival rate of the IPF patients was 46.8% (59/126), and the median survival time was 30 months after diagnosis. Glucocorticoids and/or cytotoxic drugs for patients with IPF did not change the prognosis. The survival rates between groups by gender and smoking status showed no statistically significant difference (Ward: 0.11, 1.65, P>0.05). The patients were divided into 2 groups by the median (the cutoff point value) of significant variables in univariate Cox proportional-hazards regression analysis, and the survival rates showed statistically significant difference by dyspnea scale, FVC%, TLC%, DLCO%, neutrophil percentage and eosinophil percentage in BALF, and the reticular and honeycomb lung score (Logrank: 13.52-57.52, P<0.05). The results of multivariate Cox proportional-hazards regression analysis showed that TLC%, DLCO%, HRCT reticular score and honeycomb lung score were factors that affected the prognosis of patients with IPF (Wald=5.76-21.48, P<0.05).

Conclusions: TLC%, DLCO%, cell differentials of BALF and the degree of pulmonary fibrosis were the main factors affecting the prognosis of patients with IPF. TLC% and DLCO% showed a negative correlation with the prognosis of patients with IPF. Glucocorticoids and/or cytotoxic drug therapy had no effect on the prognosis of patients with IPF.