Figure 1 of Lauwen, Mol Vis 2022; 28:536-543.

Figure 1. Hemopexin (HPX) levels plotted against sex, smoking, age, and body mass index (BMI). A and B: Bars represent median values, and whiskers represent interquartile ranges. C and D: HPX levels were log-transformed to perform linear regression. Sex, smoking, and BMI were significantly associated with HPX levels (see Table 2).