Interestingly, ApoA‐IV levels correlated with their histology scores: Low mean ApoA‐IV levels of 0.47 ± 0.1 μg/mL and 0.55 ± 0.2 μg/mL were found in healthy controls and patients with low or medium clinical scores, respectively, whereas a mean mucus level of 5.28 ± 1.8 μg/mL was observed in patients with high histology scores or patients suffering from nasal polyps (CRSwNP) (Figure 5B). Here, APOA4 is linked to chronic rhinosinusitis with nasal polyps.