PTH and chronic obstructive pulmonary disease: While survival outcome was the dependent variable, ethnicity, sex, age, weight, urine output, BMI, primary disease, hemoglobin, albumin, NT-proBNP, PTH, residual renal function, serum creatinine, blood urea nitrogen, coronary artery disease, heart failure, PVD, diabetes mellitus, hypertension, malignant neoplastic diseases and chronic obstructive pulmonary disease were independent variables.