Maria Fusaro*, Maurizio Gallieni, Andrea Aghi, Giorgio Iervasi, Maria A. Rizzo, Andrea Stucchi, Marianna Noale, Giovanni Tripepi, Thomas Nickolas, Nicola Veronese, Fabrizio Fabris, Sandro Giannini, Lorenzo Calo, Antonio Piccoli, Maria C. Mereu, Laura Cosmai, Alberto Ferraro, Fiorenza Magonara, Michela Spinello, Stefania Sella and Mario Plebani Pages 603 - 609 ( 7 )
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=0.003). Smokers had lower plasma phosphate levels (4.2 vs. 4.7 mg/dl, p<0.01). Lower BGP levels were associated with aortic calcification (p<0.001), iliac calcification (p=0.042) and vertebral fractures (p=0.023). In addition, the regression model showed that smoking is associated with a significant reduction of total BGP levels by about 18% (p=0.01).
Conclusion: This is the first clinical study in a haemodialysis population, which identifies cigarette smoking as a potential factor that can lower BGP levels, a protective agent in bone and vascular health.
BGP, osteocalcin, bone, smoke, haemodialysis, vascular calcification, vertebral fractures.
National Research Council (CNR), Institute of Clinical Physiology (IFC), Pisa Via G. Moruzzi 1, 56124, Pisa, PI, Department of Clinical and Biomedical Sciences , Department of Medicine, Clinica Medica 1, University of Padova, Padova, National Research Council (CNR), Institute of Clinical Physiology (IFC), Pisa Via G. Moruzzi 1, 56124, Pisa, PI, Nephrology and Dialysis Unit, Ospedale di Circolo di Busto Arsizio, ASST Valle Olona, Nephrology and Dialysis Unit, IRCCS Multimedica, Sesto San Giovanni (Milano), Milan, National Research Council (CNR), Neuroscience Institute, Padua, Clinical Epidemiology and Physiopathology of Renal Diseases and Hypertension, CNR, Institute of Biomedicine, Reggio Calabria, Calabria, Department of Medicine, Division of Nephrology, Columbia University Medical Center, New York, NY, Department of Medicine (DI-MED), Geriatric Section, University of Padua, Department of Medicine, Clinica Medica 1, University of Padova, Padova, Department of Medicine, Clinica Medica 1, University of Padova, Padova, Nephrology Unit, University of Padua, Padua, Nephrology Unit, University of Padua, Padua, Ospedale N.S. di Bonaria, San Gavino Monreale, Istituti Ospitalieri di Cremona, Cremona, Unita di Nefrologia di Castelfranco Veneto, Treviso, Unita di Nefrologia e Dialisi, Ospedale Alto Vicentino Santorso, Vicenza, Unita di Nefrologia-Emodialisi O.C. Piove di Sacco Ulss 6, Padova, Department of Medicine, Clinica Medica 1, University of Padova, Padova, Laboratory Medicine Unit, Department of Medicine, University of Padova, Padova