1 Department of Bariatric and Metabolic Surgery, Sana Klinikum Offenbach, Starkenburgring 66, 63069, Offenbach am Main, Hessen, Germany. Christine.stier@googlemail.com.
2 Bariatric Surgery, Department of Surgery, Brigham and Women's Hospital, 75 Francis St., ASBII-3rd Floor, Boston, MA, 02115, USA.
3 Department of Bariatric and Metabolic Surgery, Sana Klinikum Offenbach, Starkenburgring 66, 63069, Offenbach am Main, Hessen, Germany.