Received: 4 July 2018
Accepted: 22 August 2018
First Online: 4 September 2018
Ethics approval and consent to participate
: This study was approved by the Evaggelismos Hospital Scientific Committee (approval no. 271-30-10-2013; Chairman, Athanassios Skoutelis, MD, PHD, Professor of Internal Medicine), and written informed consent was obtained from the next-of-kin of all participating patients.
: Surrogates who provided informed consent for study participation also granted permission to the sharing of de-identified study data with persons authorized by the principal investigator and first author.
: The authors declare that they have no competing interests.
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