ROMO1 and chronic obstructive pulmonary disease: Serum levels of Romo1 were higher among those in the COPD group (median 5.42 ng/mL, IQR 2.84–8.72 ng/mL) vs. controls (median 3.72 ng/mL, IQR 1.64–7.59 ng/mL, p = 0.038) (Figure 2).