[Prognostic factors in survival of patients with obstructive respiratory insufficiency treated by long-term oxygen therapy. Data from the ANTADIR registry].

Prognostic survival factors in COPD patients obtaining long-term oxygen therapy (LTO) through 25 french associations were studied using data from the ANTADIR register. Selection criteria included age (50 to 79 yr), FEV1/VC < 60%, PaO2 < 60 mmHg and start of therapy between beginning 1984 and end 1988. A total of 1,775 patients were selected (1,462 men, 313 women, mean age 66.1 yr). PaO2 was 50.9 +/- 5.8 mmHg, PaCO2 47.1 +/- 5.8 mmHg, FEV1 8.81 +/- 0.31 l (30.4 +/- 11.1% of predicted values) and FEV1/VC 37.7 +/- 10.1%. Overall survival was 81.6% at 1 yr, 68.6% at 2 yrs, 55.7% at 3 yr, 44.9% at 4 yr and 37.3% at 5 yr (survival median 3.5 yr). Age was the most predictive survival factor (5 yr survival 48.8% for 50-59 yr-old patients vs 27.3% for 70-79). Survival was longer in women (49% at 5 yr vs 34.9% for men). After stratification by age, FEV1, FEV1/VC, PaO2, PaCO2 and Body Mass Index (BMI) were all significant predictive factors for men. FEV1/VC was the only prognostic factor for women. For all the population multivariate analysis showed that age, sex and BMI were the most significant variables. A prognostic score determined from the final Cox model and based on sex, age, BMI, FEV1, PaO2 will be validated in an independent patient series. Our data confirm the influence of age, airways obstruction and hypoxemia on survival of COPD patients under LTO. Furthermore they demonstrate a poorer survival in men, in underweight patients and in non hypercapnic patients.