[1] Russells Hall Hosp, Dudley Grp Hosp NHS Trust, Dept Rheumatol, Dudley DY1 2HQ, W Midlands, England
[2] Univ Ioannina, Sch Med, Dept Internal Med, GR-45110 Ioannina, Greece
[3] Russells Hall Hosp, Dudley Grp Hosp NHS Trust, Dept Cardiol, Dudley DY1 2HQ, W Midlands, England
[4] Univ Manchester, ARC Epidemiol Unit, Manchester, Lancs, England