Study About Prognostic Factor In Idiopathic Pulmonary Fibrosis

Disease incidence increased in IPF patients year by year,medical treatment connot change prognosis IPF patients,the median survival of IPF patients is 3 years after diagnosis.There are many prognostic factor in IPF patients,but unified recognition was not reached in the prognostic factor in IPF patients.New diagnostic criteria was instituted by ATS/ERS in 2000,which made the prognostic factor in IPF patients more accurate and objective.We approach prognostic implications of clinical,radiographic, and physiological variables in idiopathic pulmonary fibrosis and evaluate therapy of glucocorticoid influence on prognosis in IPF patients and analyze prognostic implications of changes and changed ratio in clinical and physiologic variables in IPF patients.Objects and methods1,Collection of patients and follow upA group of 126 patients with IPF who were referred to the Institute of Respiratory Diseases of China Medical University and studied from January 2000 until july 2004 were collected,all patients were accord with clinical diagnostic criteria.Final diagnosis in IPF patients was consided null point;Finally follow-up time is july in 2007; Failure follow-up visit or death in patients for other reason or survival in termination of follow-up visit were consided bobtail data.We visited patients every 3-6 months by clinic service and telephon and register follow-up data and confirmed cause of death.2,Selection of prognostic parametersPrognostic parameters are consist of dyspnea;pulmonary function:Forced expiratory volume in one second(FEV₁),Forced vital capacity(FVC),Total lung capacity(TLC),Residual volume(RV),Diffusing capacity of carbon monoxide(D_LCO) and all values were expressed as percentages of the predicted values;arterial blood gas: Partial pressure of oxygen in artery(PaO₂),Arterial oxygen saturation Alveolar-arterial PaO₂ difference(PA-aO₂);bronchoalveolar lavage fluid(BALF):percentage of Macrophage,percentage of Neutrophil,percentage of Lymphocyte,percentage of Ecosinophile and cell total numerus,HRCT:the extent of ground glass opacity,the extent of graticule opacity and honeycomb lung scores.We were checked out parameters of dypean,pulmonary function,arterial blood gas,BALF and HRCT in follow-up study.3,Statistical methodClinical,radiographic,and physiological variables of 126 patients were studied about prognosis in IPF patient.Of 126 patients,62 patients were studied about prognosis of therapy of glucocorticoid in earlier period influence on prognosis in IPF patients,of 126 patients 81 patients in 6 months and 52 patients in 12months were syudied prognostic implications of changes and changed ratio in clinical and physiologic variables in IPF patient.Statistical significance was established at a P value＜0.05.Statistical analysis was performed with the SPSS package software(ver 13.0,SPSS Inc).Student's t test and paired t test ANOVA independent variables were used to compare different groups of patients,chi square test qualitative variables was used to compare different groups of patients.Cox proportional hazard regression was evaluated Harzard Ratio in the IPF patients and -2Likeihood and Relative Risk(RR)were evaluated.The Kaplan-Meier method and the Log-rank test were used to estimate the survival in the two groupsResults1,Relation of basic parameters with prognosis in IPF patierntsIPF patients(median age,62yr),gender ratio 81:45,are present restrictive lung function FVC%(66±18),TLC%(58±16)and gas exchange impairment(D_LCO%:48±16).Follow-up time is 29.6 months,survival was 47.2%,the median survival of IPF patients is 30 months after diagnosis.Author found that some parameters were prognostic variables in the univariate Cox proportional hazard regression,for example dyspnea score(Ward=39.96,P＜0.0001),FVC%(Wald=6.5,P=0.01),TLC% (Wald=18.41,P＜0.0001),D_LCO%(Wald=29.82,P＜0.0001),PaO₂(Ward=9.69,P =0.002),SaO₂(Ward=8.47,P=0.004)and P_A-aO₂(Ward=4.28,P=0.04),neutrophil (Ward=13.93,P＜0.001),eosinophil(Ward=4.7,P=0.03)and lymphocytic(Ward=8.3, P=0.004)percentage,the extent of graticule opacity(Ward=33.79,P＜0.0001)and honeycomb lung scores(Ward=63.91,P=0.00001).We also found that TLC% (Wald=5.76,P=0.02),D_LCO%(Wald=7.42,P=0.006),the extent of graticule opacity (Wald=10.76,P=0.001)and honeycomb lung scores(Wald=21.48,P=0.000004)were prognostic variables in IPF patients in the multivariate Cox proportional hazard regression.2,Treatment of glucocorticosteroid with prognosis in IPF patierntsTherapy of glucocorticosteroid do not change prognosis in IPF patiemts There are 62 IPF patients with clinical diagnosis in the study,nineteen patients(30%)responded to treatment,follow-up time is 33 months.No significant differences were found in disease course and the extent of ground glass opacity in three group(P＞0.05)and significant differences were also observed in the extent of graticule opacity and honeycomb lung in three group.We found that group variables adjusted for the extent fibrosis of HRCT was prognostic variable in the Cox proportional hazard regression (b=0.881,Wald=6.62,HR=2.41,95%CI:1.23-4.72,P=0.01).and Relative Risk(RR) in aggravated patients is 2.4 times that of stable patients and 5.8 times that of improved patients.3,Relation of change of parameters in follow-up with prognosis in IPF patierntsThe extent of dyspnea and lung physiological index submit aggravated tendency in 81 IPF patients.Changed absolute value of dyspnea and pulmonary function:FEV₁%, FVC%,TLC%and D_LCO%and arterial blood gas:PaO₂,SaO₂ and P_A-aO₂ in 6 and 12 months were prognostic variables in IPF patients in the multivariate Cox proportional hazard regression.These variables were prognostic variables in IPF patients after adjusted for baseline value.Comparison with survival rate of change of dyspnea, FVC%,TLC%,D_LCO%,PaO₂,SaO₂ and P_A-aO₂ were signifciant between groups except for TLC%in 6 months.We also found that changed ratio of FVC%(HR=0.899, Wald=17.104,P=0.00004),of dyspnea(HR=1.131,Wald=4.919,P=0.027)and of PaO₂(HR=0.957,Wald=4.489,P=0.034)in 6 months and changed ratio of FVC% (HR=0.838,Wald=17.336,P=0.00003),of D_LCO%(HR=0.932,Wald=15.709, P=0.00007)and of TLC%(HR=0.962,Wald=3.895,P=0.048).Conclusion 1.TLC%,D_LCO%and the extent of pulmonary fibrosis are prognostic variables in IPF patients,TLC%and D_LCO%were negative correlation with prognosis in the IPF patients and the extent of pulmonary fibrosis was positive correlation with prognosis in the IPF patients.2.Glucocorticoid and/or cytotoxic drug could not change prognosis in the IPF patients.Therapy of glucocorticoid in earlier period affected prognosis in IPF patients, improved and stable patients have better prognosis.Therapy of glucocorticosteroid was gave in improved and stable patients and worse patients should be stoped therapy of glucocorticosteroid or changed other drugs.3.Clinical and physiological variables easily determine and reproducibility are good.The changed ratio of Clinical and physiological variables in 6 and 12 months have better prognosis,Our results highlight the further study for idiopathic pulmonary fibrosis.