Predictors of Vitamin D Status in Predialysis Chronic Kidney Disease Patients: A Cross-sectional Analysis in a High Ultraviolet Climate

25-OHD insufficiency is mitigated but still highly prevalent in patients with CKD in a high ambient UV environment. Despite the maintenance of relatively higher 25-OHD concentrations with advancing CKD, substrate availability does not appear to be a major determinant of circulating 1,25-OHD.