When comparing biomarker levels along subgroups of increasing OSA severity, there was a significant difference in HYAL-1 concentration (p = 0.03) as well as HMW-HA/HYAL-1 ratio (p = 0.005, Fig. 4), but not in HMW-HA levels (p = 0.12). This evidence concerns the gene HYAL1 and obstructive sleep apnea syndrome.