[1] Hosp Univ La Princesa, IIS Princesa, Rheumatol Div, C Diego Leon 62, Madrid 28006, Spain
[2] UAM, Catedra UAM ROCHE, EPID Future, Dept Med, Madrid, Spain
[3] Hosp Univ Marques Valdecilla, Div & Epidemiol Genet & Atherosclerosis Res Grp S, Rheumatol Div, IDIVAL, Santander, Spain
[4] Univ Witwatersrand, Fac Hlth Sci, Sch Physiol, Johannesburg, South Africa
[5] Univ Witwatersrand, Fac Hlth Sci, Sch Clin Med, Johannesburg, South Africa
[6] Univ Cantabria, Sch Med, Santander, Spain
[7] Univ Witwatersrand, Fac Hlth Sci, Sch Physiol, Cardiovasc Pathophysiol & Genom Res Unit, Johannesburg, South Africa