Notably, multivariate linear regression analysis—adjusted for age, sex, BMI, smoking status, and index—showed that IREB2 was positively correlated with the rate of FEV1 decline, whereas PSMA4 was negatively correlated with the rate of FVC decline, suggesting opposing roles in COPD progression (Figure4G‐I  and Table S10). This evidence concerns the gene PSMA4 and chronic obstructive pulmonary disease.