1. Department of Geriatric Medicine and Metabolic Diseases, Second University of Naples, Naples, Italy.
2. Institute of Gerontology and Geriatrics, Department of Clinical and Experimental Medicine, Perugia University, Perugia, Italy.
3. Laboratory of Epidemiology, Demography and Biometry, National Institute on Aging, Bethesda, Maryland.
4. Department of Nutrition and Food Science, CeRTA, Barcelona University, Spain.
5. Department of Internal Medicine and Biomedical Science, Section of Geriatrics, University of Parma, Italy.
6. Azienda Sanitaria Firenze, Florence, Italy.
7. Longitudinal Studies Section, National Institute on Aging, Baltimore, Maryland.