[1] Kent & Canterbury Hosp, E Kent Hosp NHS Trust, Dept Clin Biochem, Canterbury, Kent, England
[2] Kent & Canterbury Hosp, E Kent Hosp NHS Trust, Dept Hlth Care Older Person, Canterbury, Kent, England
[3] Kent & Canterbury Hosp, E Kent Hosp NHS Trust, Dept Renal Med, Canterbury, Kent, England
[4] St Helier Hosp, SW Thames Inst Renal Res, Carshalton SM5 1AA, Surrey, England