Figure 3. Univariable associations with exacerbation-free survival.
Cox Proportional hazards regression analysis of freedom from pulmonary exacerbations. Age in years, KPS, smoking status (former smoker versus never smoker), baseline FEV, and number of weeks of steroid treatment prior to enrollment did not have a statistically significant association with the hazard of pulmonary exacerbation. Hazard ratios (HR) are plotted with with 95% confidence intervals (CI) in panel B.