Nutrition-related factors associated with waiting list mortality in patients with interstitial lung disease: A retrospective cohort study.

Japanese patients with interstitial lung disease (ILD) sometimes die waiting for lung transplantation (LTx) because it takes about 2 years to receive it in Japan. We evaluated nutrition-related factors associated with waiting list mortality. Seventy-six ILD patients were hospitalized in Kyoto University Hospital at registration for LTx from 2013 to 2015. Among them, 40 patients were included and analyzed. Patient background was as follows: female, 30%; age, 50.3 ± 6.9 years; body mass index, 21.1 ± 4.0 kg/m2 ; 6-minute walk distance (6MWD), 356 ± 172 m; serum albumin, 3.8 ± 0.4 g/dL; serum transthyretin (TTR), 25.3 ± 7.5 mg/dL; and C-reactive protein, 0.5 ± 0.5 mg/dL. Median observational period was 497 (range 97-1015) days, and median survival time was 550 (95% CI 414-686) days. Survival rate was 47.5%, and mortality rate was 38.7/100 person-years. Cox analyses showed that TTR (HR 0.791, 95% CI 0.633-0.988) and 6MWD (HR 0.795, 95% CI 0.674-0.938) were independently correlated with mortality and were influenced by body fat mass and leg skeletal muscle mass, respectively. It is suggested that nutritional markers and exercise capacity are important prognostic markers in waitlisted patients, but further study is needed to determine whether nutritional intervention or exercise can change outcomes.