1. Medical Area Department, University of Udine, Udine, Italy;
2. Neurologic Clinic, Department of Medical, Surgical and Health Sciences, Azienda Sanitaria Universitaria Integrata di Trieste, University Hospital of Trieste, Trieste, Italy;
3. Neurologic Clinic, Department of Neurological Sciences, Azienda Sanitaria Universitaria Integrata di Udine, Udine, Italy;
4. Neurologic Clinic, Hospital of Gorizia, Gorizia, Italy;
5. Neurologic Clinic, Hospital of Pordenone, Pordenone, Italy;
6. Leibniz Institute for Prevention Research and Epidemiology - BIPS, Bremen, Germany;
7. Institute of Hygiene and Clinical Epidemiology, University Hospital of Udine, Udine, Italy