1. Department of Neurosurgery, Istituto Scientifico San Raffaele; Università Vita-Salute, Milan, Italy.
2. Diabetes and Endocrinology Unit, Department of Medicine; Istituto Scientifico San Raffaele, Università Vita-Salute, Milan, Italy.
3. Nutrition Unit, Department of Medicine; Istituto Scientifico San Raffaele, Università Vita-Salute, Milan, Italy.
4. Division of Epidemiology and Biostatistics, Department of Internal Medicine, University of New Mexico Health Sciences Center, Albuquerque, New Mexico.