Second, in addition to the traditional factors such as reduced BMI, poor lung function as measured by FEV1 percent predicted, and presence of Pseudomonas aeruginosa in sputum cultures, we found that plasma levels of two early phase inflammatory cytokines, IL-6 and IL-1β, were significantly associated with prior hospitalization in patients with CF, independent of the traditional factors. Here, IL1B is linked to cystic fibrosis.