[1] Massachusetts Gen Hosp, Div Cardiol, Boston, MA USA
[2] Harvard Med Sch, Boston, MA USA
[3] Univ Auckland, Fac Med & Hlth Sci, Sch Populat Hlth, Sect Epidemiol & Biostat, Auckland, New Zealand
[4] Univ Galway, Sch Med, Cardiol Dept, Galway, Ireland
[5] Natl Inst Prevent & Cardiovasc Hlth, Galway, Ireland
[6] Univ Oxford, Nuffield Dept Reprod & Womens Hlth, Deep Med, Oxford OX1 2BQ, England