Chronic kidney disease is associated with progressive increase in arterial stiffness and bone-muscle loss over 1 year

Abstract

Aim: To assess changes in bone structure, muscle mass, arterial stiffness, physical function and bone markers in stage 4/5 chronic kidney disease (CKD) compared with healthy controls. Background: The relationships between vascular, bone and muscular structural and functional changes have not been well studied in CKD. Methods: In this prospective, single-centre, longitudinal observational study, bone and muscle structure [cortical bone mineral density (cBMD), trabecular bone mineral density (tBMD), strength-strain index (SSI), bone and muscle cross-sectional area (CSA)], physical function [6-minute walk test (6MWT), timed up and go (TUG) test], arterial stiffness [pulse wave velocity (PWV)] and plasma fibroblast growth factor23 (FGF23) were compared between CKD stage 4/5 and controls at baseline and 12 months. Bone-muscle indices were determined by peripheral quantitative computed tomography (pQCT) scanning of the radius. Results: 40 CKD [mean estimated glomerular filtration rate (eGFR): 19.5 ± 6.7 mL/min/1.73 m2] and 42 controls (eGFR: 88.6 ± 12.9 mL/min/ 1.73 m2) completed follow-up. CKD subjects had a significant loss of bone density, area and strength (cBMD: 1077.0 ± 54.5 mg/cm3 to 1067.3 ± 53.0 mg/ cm3, p = 0.01; tBMD: 189.1 ± 53.2 mg/cm3 to 185.8 ± 53.2 mg/cm3, p = 0.03; cortical CSA: 88.8 ± 22.4 mm2 to 87.3 ± 22.4 mm2, p = 0.01; SSI: 382.2 ± 122.6 mm3 to 365.7 ± 117.0 mm3, p = 0.03). PWV significantly increased by 1.3 m/s (16.7%, p < 0.001) among CKD subjects. There were also marked reductions in muscle CSA (3522.7 ± 1008.7 mm2 to 3380 ± 950.4 mm2, p = 0.002) and physical function (TUG test: 6.9 ± 2.3 s to 7.7 ± 2.3 s, p = 0.003; 6MWT: 496.4 ± 89.5 m to 457.0 ± 91.4 m, p = 0.002). FGF23 levels increased [240.6 (141.9-1129.8) to 396.8 (160.3-997.7) p = 0.001] and was independently associated with changes in cBMD, muscle CSA and PWV. No changes were observed in bone, vascular, muscular and functional parameters among controls after a year. Conclusions: CKD was associated with significant losses of bone and muscular structure and function and greater increases in arterial stiffness and FGF23 levels over 12 months.<br />