Mortality prediction in idiopathic pulmonary fibrosis: evaluation of computer-based CT analysis with conventional severity measures

[摘要] Computer-based computed tomography (CT) analysis can provide objective quantitation of disease in idiopathic pulmonary fibrosis (IPF). A computer algorithm; CALIPER; was compared with conventional CT and pulmonary function measures of disease severity for mortality prediction.CT and pulmonary function variables (forced expiratory volume in 1xe2x80x85s; forced vital capacity; diffusion capacity of the lung for carbon monoxide; transfer coefficient of the lung for carbon monoxide and composite physiologic index (CPI)) of 283 consecutive patients with a multidisciplinary diagnosis of IPF were evaluated against mortality. Visual and CALIPER CT features included total extent of interstitial lung disease; honeycombing; reticular pattern; ground glass opacities and emphysema. In addition; CALIPER scored pulmonary vessel volume (PVV) while traction bronchiectasis and consolidation were only scored visually. A combination of mortality predictors was compared with the Gender; Age; Physiology model.On univariate analyses; all visual and CALIPER-derived interstitial features and functional indices were predictive of mortality to a 0.01 level of significance. On multivariate analysis; visual CT parameters were discarded. Independent predictors of mortality were CPI (hazard ratio (95% CI) 1.05 (1.02xe2x80x931.07); p<0.001) and two CALIPER parameters: PVV (1.23 (1.08xe2x80x931.40); p=0.001) and honeycombing (1.18 (1.06xe2x80x931.32); p=0.002). A three-group staging system derived from this model was powerfully predictive of mortality (2.23 (1.85xe2x80x932.69); p<0.0001).CALIPER-derived parameters; in particular PVV; are more accurate prognostically than traditional visual CT scores. Quantitative tools such as CALIPER have the potential to improve staging systems in IPF.

[学科分类] 呼吸医学