affiliation not provided to SSRN, National and Kapodistrian University of Athens - Laiko General Hospital, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, Aristotle University of Thessaloniki - Fourth Department of Internal Medicine, Aristotle University of Thessaloniki, affiliation not provided to SSRN, affiliation not provided to SSRN, University of Bari, affiliation not provided to SSRN, National and Kapodistrian University of Athens, National and Kapodistrian University of Athens - First Department of Propaedeutic and Internal Medicine, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN, affiliation not provided to SSRN and affiliation not provided to SSRN