Figures
- FIGURE 1
Axial computed tomography (CT) images a) at baseline and b) at a 12-month follow-up scan, in a patient with idiopathic pulmonary fibrosis (IPF). b) Note more progressive reticulation in the right lower lobe with new areas of subpleural reticulation in the left lower lobe (red arrows). Axial CT images in another patient with IPF c) at baseline and d) at a 12-month follow-up scan. d) Note the progressive honeycombing (red arrows), traction dilation of the airways (yellow arrow) and reticulation in both lobes (blue arrows).
Tables
- TABLE 1
Comparison of mortality risk scoring systems in idiopathic pulmonary fibrosis
Variables Predictive value Advantages Disadvantages Composite physiologic index (CPI) [9] DLCO % pred
FVC % pred
FEV1 % pred
Correlation with morphologic extent:
CPI=91.0−(0.65×DLCO)−(0.53×FVC)+(0.34 FEV1)More accurate predictor of mortality than individual functional variables Correction for confounding effects of emphysema Retrospective data;
measurement variability in DLCO;
not yet been replicatedDu Bois et al. model [7] Age (0–8 pts)
24-week history of respiratory hospitalisation (0 or 14 pts)
FVC % pred (0–18 pts)
24-week change in FVC (0–21 pts)1-year mortality risk
Examples total score:
• 0–4 pts: <2%
• 22–29 pts: 10–20%
• 38–40 pts: 40–50%
• >50 pts: >80%Easily and reliably evaluable;
longitudinal variablesAssessed in cohorts with only mild to moderate physiological impairment at baseline and with exclusion of severe emphysema Gender–age–physiology (GAP) model [82] Gender (0–1 pts)
Age (0–2 pts)
FVC % pred (0–2 pts)
DLCO % pred (0–3 pts)Cumulative mortality at 1, 2, 3 years
Examples 1-year mortality risk:
Stage I (0–3 pts): 6%
Stage II (4–5 pts): 16%
Stage III (6–8 pts): 39%Externally validated
GAP calculator as add-on tool for more precise estimation of riskRetrospective data;
possible referral bias (academic centres);
tends to overestimate riskLongitudinal GAP model [83] Gender (0–1 pts)
Age (0–4 pts)
FVC % pred (0–15 pts)
24-week relative change in FVC (0–12 pts)
DLCO % pred (0–23 pts)
Respiratory hospitalisation
(last 24 weeks) (0 or 14 pts)1 and 2-year mortality risk
Examples 1-year mortality risk:
• 0–10 pts: <2%
• 27–34 pts: 10–20%
• 43–45 pts: 40–50%
• 55–60 pts: ≥80%Longitudinal risk assessment;
prospective dataNo external validation CT-GAP model [8] Gender
Age
FVC % pred
Semi-quantitative CT fibrosis scoreCumulative mortality at 1, 2, 3 years
Examples 1-year mortality risk:
Stage I (0–3 pts): 5%
Stage II (4–5 pts): 19%
Stage III (6–8 pts): 43%Accuracy comparable to that of the original GAP model; alternative model when DLCO unmeasurable or not available; externally validated Retrospective data;
requires expertise in quantification of CT disease extentDLCO: diffusing capacity of carbon monoxide; FVC: forced vital capacity; FEV1: forced expiratory volume in 1 s; CT: computed tomography; % pred: % predicted; pts: points. Reproduced and modified from [89] with permission from the publisher.
