PTH and Marchiafava-Bignami disease: Next, we investigated clinical parameters associated with f(HNA) using multivariate analysis, with age, gender, body mass index (BMI), aspartate transaminase (AST), hemoglobin (marker of renal anemia), uric acid, sodium-chloride (marker of metabolic acidosis), intact-PTH [marker of CKD mineral and bone disorder (CKD-MBD)], eGFR, and urinary protein included as explanatory variables.