title: Fluid intake and all-cause mortality, cardiovascular mortality and kidney function: a population-based longitudinal cohort study.
abstract: BACKGROUND
  Drinking eight glasses of fluid or water each day is widely believed to improve health, but evidence is sparse and conflicting. We aimed to investigate the association between fluid consumption and long-term mortality and kidney function.
  
  
  METHODS
  We conducted a longitudinal analysis within a prospective, population-based cohort study of 3858 men and women aged 49 years or older residing in Australia. Daily fluid intake from food and beverages not including water was measured using a food frequency questionnaire. We did multivariable adjusted Cox proportional hazard models for all-cause and cardiovascular mortality and a boot-strapping procedure for estimated glomerular filtration rate (eGFR).
  
  
  RESULTS
  Upper and lower quartiles of daily fluid intake corresponded to >3 L and <2 L, respectively. During a median follow-up of 13.1 years (total 43 093 years at risk), 1127 deaths (26.1 per 1000 years at risk) including 580 cardiovascular deaths (13.5 per 1000 years at risk) occurred. Daily fluid intake (per 250 mL increase) was not associated with all-cause [adjusted hazard ratio (HR) 0.99 (95% CI 0.98-1.01)] or cardiovascular mortality [HR 0.98 (95% CI 0.95-1.01)]. Overall, eGFR reduced by 2.2 mL/min per 1.73 m(2) (SD 10.9) in the 1207 (31%) participants who had repeat creatinine measurements and this was not associated with fluid intake [adjusted regression coefficient 0.06 mL/min/1.73 m(2) per 250 mL increase (95% CI -0.03 to 0.14)].
  
  
  CONCLUSIONS
  Fluid intake from food and beverages excluding water is not associated with improved kidney function or reduced mortality.
authors.affiliation: Department of Medicine, University of Otago, Christchurch, New Zealand.
authors.forename: Suetonia C
authors.initials: SC
authors.lastname: Palmer
authors.affiliation: School of Public Health, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia.
authors.forename: Germaine
authors.initials: G
authors.lastname: Wong
authors.affiliation: Centre for Kidney Research, Children's Hospital at Westmead, Westmead, NSW, Australia.
authors.forename: Samuel
authors.initials: S
authors.lastname: Iff
authors.affiliation: School of Mathematics and Statistics, The University of Sydney, Sydney, NSW, Australia.
authors.forename: Jean
authors.initials: J
authors.lastname: Yang
authors.affiliation: School of Mathematics and Statistics, The University of Sydney, Sydney, NSW, Australia.
authors.forename: Vivek
authors.initials: V
authors.lastname: Jayaswal
authors.affiliation: School of Public Health, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia Centre for Kidney Research, Children's Hospital at Westmead, Westmead, NSW, Australia.
authors.forename: Jonathan C
authors.initials: JC
authors.lastname: Craig
authors.affiliation: Centre for Vision Research, Westmead Millennium Institute and Clinical Ophthalmology and Eye Health, Westmead Clinical School, The University of Sydney, C24 - Westmead Hospital, Sydney, NSW, Australia.
authors.forename: Elena
authors.initials: E
authors.lastname: Rochtchina
authors.affiliation: Centre for Vision Research, Westmead Millennium Institute and Clinical Ophthalmology and Eye Health, Westmead Clinical School, The University of Sydney, C24 - Westmead Hospital, Sydney, NSW, Australia.
authors.forename: Paul
authors.initials: P
authors.lastname: Mitchell
authors.affiliation: Centre for Vision Research, Westmead Millennium Institute and Clinical Ophthalmology and Eye Health, Westmead Clinical School, The University of Sydney, C24 - Westmead Hospital, Sydney, NSW, Australia.
authors.forename: Jie Jin
authors.initials: JJ
authors.lastname: Wang
authors.affiliation: School of Public Health, Sydney Medical School, The University of Sydney, Sydney, NSW, Australia Department of Clinical Pharmacology and Epidemiology, Consorzio Mario Negri Sud, S. Maria Imbaro 66030, Italy Diaverum Scientific Office, Lund, Sweden Department of Emergency and Organ Transplantation, University of Bari, Bari, Italy.
authors.forename: Giovanni F M
authors.initials: GF
authors.lastname: Strippoli
mesh_terms: D000368:Aged; D001315:Australia / Q000453:epidemiology; D002318:Cardiovascular Diseases / Q000453:epidemiology / Q000401:mortality* / Q000503:physiopathology; D002423:Cause of Death; D004326:Drinking; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D015994:Incidence; D007668:Kidney / Q000502:physiology*; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D015996:Survival Rate
keywords: chronic kidney disease; fluid intake; glomerular filtration rate; mortality