African-American race and mortality in interstitial lung disease: a multicentre propensity-matched analysis.

We studied whether African-American race is associated with younger age and decreased survival time at diagnosis of interstitial lung disease (ILD).We performed a multicentre, propensity score-matched analysis of patients with an ILD diagnosis followed at five US hospitals between 2006 and 2016. African-Americans were matched with patients of other races based on a time-dependent propensity score calculated from multiple patient, physiological, diagnostic and hospital characteristics. Multivariable logistic regression models were used. All-cause mortality and hospitalisations were compared between race-stratified patient cohorts with ILD, and sensitivity analyses were performed.The study included 1640 patients with ILD, 13% of whom were African-American, followed over 5041 person-years. When compared with patients of other races, African-Americans with ILD were younger at diagnosis (56 years versus 67 years), but in the propensity-matched analyses had greater survival (hazard ratio 0.46, 95% CI 0.28-0.77; p=0.003) despite similar risk of respiratory hospitalisations (relative risk 1.04, 95% CI 0.83-1.31; p=0.709), and similar GAP-ILD (gender-age-physiology-ILD) scores at study entry. Sensitivity analyses in a separate cohort of 9503 patients with code-based ILD diagnosis demonstrated a similar association of baseline demographic characteristics with all-cause mortality.We conclude that African-Americans demonstrate a unique phenotype associated with younger age at ILD diagnosis and perhaps longer survival time.
Competing Interests: Conflict of interest: R. Vij received a grant from Genentech to study the genomics of autoimmune interstitial lung diseases. Conflict of interest: I. Noth received honoraria for advisory boards from Boehringer Ingelheim, InterMune and Anthera within the last 12 months related to IPF. He has also received speaking honoraria from GSK and consulting fees for Immuneworks. He also has study contracts with the NIH, Stromedix, Sanofi and BI for the conduct of clinical trials in IPF. Conflict of interest: M.M. Churpek is supported by a career development award from the National Heart, Lung, and Blood Institute (K08 HL121080), has received honoraria from Chest for invited speaking engagements and also has a patent pending (ARCD.P0535US.P2) for risk stratification algorithms for hospitalised patients. Conflict of interest: M.E Strek received institutional funding for interstitial lung disease research from Genentech, Gilead and MedImmune, and serves on a data monitoring committee for Boehringer Ingelheim. Conflict of interest: J.M. Oldham received speaking and advisory board fees from Genentech and Boehringer Ingelheim.
(Copyright ©ERS 2018.)