In the COPD group, serum d–ROMs levels were positively correlated with CAT and total SGRQ scores (rs = 0.442, p < 0.001; rs = 0.406, p = 0.001, respectively) (Figure 7); this was also the case in the ACO group (rs = 0.329, p = 0.034, rs = 0.440, p < 0.004, respectively) (Figure 8). The gene discussed is CAT; the disease is chronic obstructive pulmonary disease.