[1] Univ Hong Kong, Queen Mary Hosp, Dept Med, Div Geriatr Med, Hong Kong, Hong Kong, Peoples R China
[2] Queen Mary Hosp, Div Clin Biochem, Hong Kong, Hong Kong, Peoples R China
[3] Univ Hong Kong, Fac Med, Queen Mary Hosp, Dept Med, Hong Kong, Hong Kong, Peoples R China
[4] Univ Hong Kong, Fac Med, Dept Med, Family Med Unit, Hong Kong, Hong Kong, Peoples R China
[5] Univ Hong Kong, Fac Med, Dept Psychiat, Hong Kong, Hong Kong, Peoples R China
[6] Family Planning Associat Hong Kong, Hong Kong, Hong Kong, Peoples R China
[7] St Louis Univ, Sch Med, Div Geriatr Med, St Louis, MO 63104 USA