FGF23 and chronic kidney disease: <b>Methods</b>: In 1968 adults with non-dialysis CKD (mean age 68 ± 12 years; 34% female; mean follow-up duration 3.02 ± 0.35 years), annualized slopes of CKD-MBD biomarkers (PTH, FGF23, phosphate, calcium) were derived from mixed-effects models, alongside slopes and intra-individual variability of other key features of CKD-eGFR, hemoglobin, albumin, bicarbonate, 25-hydroxyvitamin D, uric acid, urine albumin creatinine ratio (UACR).