Multivariable logistic regression analysis adjusted by age, gender, medication use history, CRP and ESR revealed that serum bilirubin was independently associated with ILD in patients with pSS (OR = 0.841, 95%CI:0.728–0.972, p = 0.019), moreover, multivariable logistic regression analysis found that older age was a significantly risk factor of ILD in patients with pSS (OR = 1.060, 95%CI: 1.009–1.114, p = 0.021), as shown in Table 2. Here, CRP is linked to interstitial lung disease.