CHI3L1 and Respiratory insufficiency: Multivariable Cox regression analysis revealed that CHI3L1 plasma levels (ng/mL) at admission predict the risk of adverse outcome (transfer to ICU/death) independently of age, sex, comorbidities, degree of respiratory insufficiency and systemic inflammation (CRP) at admission, and time from symptom onset to blood draw (p < 0.01, Table 2).