Laboratory measurements
Renal disease
WEST, RENAL DISEASE, BLOOD
All blood samples were obtained after at least a 2 h fast. Samples for routine laboratory measurements were taken at baseline and at 18 months. Biochemical tests included renal/liver/bone profile, parathyroid hormone (PTH) and were done by standard laboratory methods on the Roche automated analysers (Roche diagnostics Limited, West Sussex, UK). eGFR was calculated from serum creatinine using the Modification of Diet in Renal disease formula. Vitamin D status was determined by measurement of 25-hydroxy vitamin D (25(OH)D) using an immunoassay on the automated Abbott Architect analyser (Abbott Laboratories, Abbott Park, Illinois, USA). PTH assay CVs were < 5% at PTH concentrations of 41 and 105 ng/L. 25(OH)vitamin D assay CVs ranged between 5.0 and 10.7% at serum 25 (OH)vitamin D concentrations between 25 and 85 nmol/L. The reference ranges for PTH is 10–65 ng/L, serum albumin: 40–52 g/L, serum creatinine: 45-84 µmol/L. Serum 25(OH)vitamin D > 50 nmol/L is considered sufficient, 25–50 nmol/L: insufficient and < 25 nmol/L: deficient.Blood samples for serum vitamin K