[1] Univ Edinburgh, Ctr Clin Brain Sci, Edinburgh, Scotland
[2] Univ Edinburgh, Usher Inst, Geriatr Med, Edinburgh, Scotland
[3] Newcastle Univ, Populat Hlth Sci Inst, Newcastle Upon Tyne, England
[4] Karolinska Inst, Div Clin Geriatr, Stockholm, Sweden
[5] Univ Glasgow, Inst Cardiovasc & Med Sci, Glasgow, Scotland
[6] Univ Edinburgh, Royal Infirm Edinburgh, Usher Inst, Geriatr Med, 51 Little France Crescent, Edinburgh EH16 4SB, Scotland