du Bois Score for IPF Mortality

Why use it

Provides individualized mortality risk estimates in IPF beyond FVC alone. Captures dynamic disease progression (change in FVC at 24 weeks) which significantly refines prognosis. Clinically validated and endorsed by ATS/ERS/JRS/ALAT for serial assessment. The 24-week decline in FVC is the strongest predictor of mortality in IPF and should be routinely measured.

About

The du Bois 4-variable clinical prediction model estimates 1-year mortality risk in patients with idiopathic pulmonary fibrosis (IPF). It was derived from pooled placebo data from three phase 3 clinical trials (CAPACITY 004, CAPACITY 006, and INSPIRE). The model uses four readily available variables: age, recent respiratory hospitalization (past 24 weeks), baseline % predicted FVC, and 24-week change in % predicted FVC. It is particularly useful for serial risk stratification and clinical trial enrichment, as it can capture functional decline over time. A simplified point-based version (PILOT) was also developed from this model for bedside use.

When to use

• At baseline and every 6 months in established IPF diagnosis
• After 24 weeks of antifibrotic therapy to assess treatment response and prognosis
• Pre-transplant evaluation to determine urgency of listing
• Identifying high-risk patients for clinical trial enrollment
• Goals-of-care discussions and advance care planning in IPF

Formula

Pearls & pitfalls

• The 24-week change in FVC % predicted is the most powerful prognostic variable — even a 2–5% absolute decline doubles mortality risk.
• Respiratory hospitalization in the past 24 weeks is associated with ~3× increased mortality risk — acute exacerbations carry very high short-term mortality.
• FVC decline ≥ 10% absolute OR ≥ 15% relative over 6 months meets ATS/ERS threshold for clinically significant progression.
• At baseline (before 24-week data), only age and FVC% are used — prognosis improves significantly once longitudinal data is available.
• GAP (Gender, Age, Physiology) index and staging system is an alternative prognostic tool for IPF that uses gender, age, FVC, and DLCO.
• Antifibrotic therapy (nintedanib, pirfenidone) slows FVC decline but does not eliminate progressive disease — serial monitoring is mandatory.
• Supplemental oxygen, pulmonary rehabilitation, and early transplant referral improve quality of life in high-risk patients.

Next steps

Low risk (<3% predicted 1-year mortality): Continue antifibrotic therapy, monitor every 6 months. Intermediate risk (3–10%): Intensify monitoring, reassess transplant candidacy. High risk (>10%): Urgent transplant listing evaluation, palliative care referral, goals-of-care discussion. ANY patient with absolute decline in FVC ≥ 10% in 6 months has high mortality risk regardless of absolute FVC value.

Evidence

du Bois RM et al. Ascertainment of individual risk of mortality for patients with idiopathic pulmonary fibrosis. Am J Respir Crit Care Med. 2011;184(4):459-466. Derived from pooled data of 1,099 IPF patients from phase 3 trials. C-statistic 0.73 for 1-year mortality. Validated externally in multiple independent cohorts.

References

1. du Bois RM et al. Ascertainment of individual risk of mortality for patients with idiopathic pulmonary fibrosis. Am J Respir Crit Care Med. 2011;184(4):459-466. — link
2. Ley B et al. A multidimensional index and staging system for IPF. Ann Intern Med. 2012;156(10):684-691. — link
3. Raghu G et al. An Official ATS/ERS/JRS/ALAT Statement: Idiopathic Pulmonary Fibrosis: Evidence-based Guidelines for Diagnosis and Management. Am J Respir Crit Care Med. 2011;183(6):788-824. — link