Health care access and prevalence of the metabolic syndrome among elders living in high-altitude areas of the Mediterranean islands: the MEDIS study - Tyrovolas, S; Chalkias, C; Morena, M; Tsiligianni, I; Zeimbekis, A; Gotsis, E; Metallinos, G; Bountziouka, V; Polychronopoulos, E; Lionis, C; Panagiotakos, D (Rev Diabet Stud, 2011)