MUC1 and idiopathic pulmonary fibrosis: However, a significantly greater proportion of patients in the “mucin-1 ≥ 2.5” group suffered a 24-week decline of ≥ 10% in DLCO than in the “mucin-1 < 2.5” group, and this finding persisted after patients with on-treatment AE-IPF had been excluded (Figure 5h).