Low vitamin K1 intake in haemodialysis patients
Background & aims Vitamin K acts as a coenzyme in the γ-carboxylation of vitamin K-dependent proteins, including coagulation factors, osteocalcin, matrix Gla protein (MGP), and the growth arrest-specific 6 (GAS6) protein. Osteocalcin is a key factor for bone matrix formation. MGP is a local inhibitor of soft tissue calcification. GAS6 activity prevents the apoptosis of vascular smooth muscle cells. Few data on vitamin K intake in chronic kidney disease patients and no data in patients on a Mediterranean diet are available. In the present study, we evaluate the dietary intake of vitamin K1 in a cohort of patients undergoing haemodialysis. Methods In this multi-centre controlled observati…
Nephrolithiasis, bone mineral density, osteoporosis, and fractures: a systematic review and comparative meta-analysis
Summary: Our meta-analysis demonstrates that people with nephrolithiasis have decreased bone mineral density, an increased odds of osteoporosis, and potentially an elevated risk of fractures. Introduction: People with nephrolithiasis might be at risk of reduced bone mineral density (BMD) and fractures, but the data is equivocal. We conducted a meta-analysis to investigate if patients with nephrolithiasis have worse bone health outcomes (BMD), osteoporosis, and fractures versus healthy controls (HCs). Methods: Two investigators searched major databases for articles reporting BMD (expressed as g/cm2 or a T- or Z-score), osteoporosis or fractures in a sample of people with nephrolithiasis, and…
Cigarette Smoking is Associated with Decreased Bone Gla-protein (BGP) Levels in Hemodialysis Patients
Background: Bone Gamma-carboxyglutamic acid (Gla)-protein (BGP or osteocalcin) is a vitamin K-dependent protein involved in the regulation of bone mineralization. Smoking is a risk factor for osteoporosis. Methods: We carried out a secondary analysis of the Vitamin K Italian (VIKI) study to investigate the association between cigarette smoking and BGP levels in patients with end stage renal disease. Data were collected in 370 haemodialysis patients, 37% (136) smokers (or ex-smokers) and 63% (234) nonsmokers. Vascular calcifications and vertebral fractures (quantitative morphometry) were identified on spine radiographs. Results: Smokers had significantly lower BGP levels (152 vs. 204 μg/L, p…