1. Institute for Clinical Diabetology, German Diabetes Center, Leibniz Center for Diabetes Research at Heinrich Heine University Düsseldorf, Düsseldorf, Germany
2. Department of Endocrinology and Diabetology, Medical Faculty and University Hospital Düsseldorf, Heinrich Heine University Düsseldorf, Düsseldorf, Germany
3. Department of Internal Medicine, Israelite Hospital, Hamburg, Germany
4. Department of Pain Medicine, Ruhr University, Bochum, Germany
5. Neuro-Urology, Swiss Paraplegic Center Nottwil, Switzerland