[1] Jichi Med Univ, Dept Cardiol, Shimotsuke, Tochigi, Japan
[2] Univ Milano Bicocca, Dept Clin Med & Prevent, Dept Cardiol, Ist Auxol Italiano, Milan, Italy
[3] Univ Barcelona, Dept Internal Med, Hosp Mutua Terrassa, Barcelona, Spain
[4] Autonomous Univ Madrid, Dept Epidemiol & Publ Hlth, E-28049 Madrid, Spain
[5] Hosp San Agustin, Dept Nephrol, Aviles, Spain
[6] Hosp 12 Octubre, Hypertens Unit, E-28041 Madrid, Spain