GPT and chronic bronchitis: Missing data were present in the following variables: BMI, CRP, albumin, alanine aminotransferase, blood urea nitrogen, total cholesterol, triglyceride, creatinine, education status, PIR, smoking, hypertension, asthma, arthritis, emphysema, chronic bronchitis, liver disease, cancer, CHF, CHD, AP, HT, and stroke.