[1] Aristotle Univ Thessaloniki, Sch Med, Hippokration Hosp, Propedeut Dept Internal Med 2, GR-54006 Thessaloniki, Greece
[2] UCL, Sch Med, Propedeut Dept Internal Med 1, AHEPA Hosp, London NW3 2QG, England
[3] UCL, Sch Med, Dept Clin Biochem, Vasc Dis Prevent Clin, London NW3 2QG, England