1. Clinic for Neurology, Friedrich-Alexander-University Hospital Erlangen, 91054 Erlangen, Germany
2. Clinic for Neurology, Westpfalz-Klinikum Kaiserslautern, 67655 Kaiserslautern, Germany
3. Clinic for Neurology, University Hospital Homburg, 66421 Homburg, Germany
4. Department of Periodontology and Operative Dentistry, University Medical Center of the Johannes Gutenberg University Mainz, 55131 Mainz, Germany
5. Clinical Neurology, Miller School of Medicine, University of Miami, Coral Gables, FL 33146, USA
6. Department of Biometry and Epidemiology, Friedrich-Alexander-University Erlangen, 91054 Erlangen, Germany