title: Association between urinary sodium, creatinine, albumin, and long-term survival in chronic kidney disease.
abstract: Dietary sodium intake is associated with hypertension and cardiovascular risk in the general population. In patients with chronic kidney disease, sodium intake has been associated with progressive renal disease, but not independently of proteinuria. We studied the relationship between urinary sodium (UNa) excretion and UNa to creatinine ratio and mortality or requirement for renal replacement therapy in chronic kidney disease. Adult patients attending a renal clinic who had ≥1 24-hour UNa measurement were identified. Twenty-four-hour UNa measures were collected and UNa to creatinine ratio calculated. Time to renal replacement therapy or death was recorded. Four hundred twenty-three patients were identified with mean estimated glomerular filtration rate of 48 mL/min per 1.73 m(2). Ninety patients required renal replacement therapy and 102 patients died. Mean slope decline in estimated glomerular filtration rate was -2.8 mL/min per 1.73 m(2) per year. Median follow-up was 8.5 years. Patients who died or required renal replacement therapy had significantly higher UNa excretion and UNa to creatinine ratio, but the association with these parameters and poor outcome was not independent of renal function, age, and albuminuria. When stratified by albuminuria, UNa to creatinine ratio was a significant cumulative additional risk for mortality, even in patients with low-level albuminuria. There was no association between low UNa and risk, as observed in some studies. This study demonstrates an association between UNa excretion and mortality in chronic kidney disease, with a cumulative relationship between sodium excretion, albuminuria, and reduced survival. These data support reducing dietary sodium intake in chronic kidney disease, but additional study is required to determine the target sodium intake.
authors.affiliation: From Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (E.P.M., A.H.T., E.M.F., A.G.J., P.B.M.); The Glasgow Renal and Transplant Unit, Western Infirmary, Glasgow, United Kingdom (E.P.M., A.H.T., J.G.F., A.G.J., P.B.M.); and Renal Unit, Monklands Hospital, Airdrie, United Kingdom (J.P.T.).
authors.forename: Emily P
authors.initials: EP
authors.lastname: McQuarrie
authors.affiliation: From Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (E.P.M., A.H.T., E.M.F., A.G.J., P.B.M.); The Glasgow Renal and Transplant Unit, Western Infirmary, Glasgow, United Kingdom (E.P.M., A.H.T., J.G.F., A.G.J., P.B.M.); and Renal Unit, Monklands Hospital, Airdrie, United Kingdom (J.P.T.).
authors.forename: Jamie P
authors.initials: JP
authors.lastname: Traynor
authors.affiliation: From Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (E.P.M., A.H.T., E.M.F., A.G.J., P.B.M.); The Glasgow Renal and Transplant Unit, Western Infirmary, Glasgow, United Kingdom (E.P.M., A.H.T., J.G.F., A.G.J., P.B.M.); and Renal Unit, Monklands Hospital, Airdrie, United Kingdom (J.P.T.).
authors.forename: Alison H
authors.initials: AH
authors.lastname: Taylor
authors.affiliation: From Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (E.P.M., A.H.T., E.M.F., A.G.J., P.B.M.); The Glasgow Renal and Transplant Unit, Western Infirmary, Glasgow, United Kingdom (E.P.M., A.H.T., J.G.F., A.G.J., P.B.M.); and Renal Unit, Monklands Hospital, Airdrie, United Kingdom (J.P.T.).
authors.forename: E Marie
authors.initials: EM
authors.lastname: Freel
authors.affiliation: From Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (E.P.M., A.H.T., E.M.F., A.G.J., P.B.M.); The Glasgow Renal and Transplant Unit, Western Infirmary, Glasgow, United Kingdom (E.P.M., A.H.T., J.G.F., A.G.J., P.B.M.); and Renal Unit, Monklands Hospital, Airdrie, United Kingdom (J.P.T.).
authors.forename: Jonathan G
authors.initials: JG
authors.lastname: Fox
authors.affiliation: From Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (E.P.M., A.H.T., E.M.F., A.G.J., P.B.M.); The Glasgow Renal and Transplant Unit, Western Infirmary, Glasgow, United Kingdom (E.P.M., A.H.T., J.G.F., A.G.J., P.B.M.); and Renal Unit, Monklands Hospital, Airdrie, United Kingdom (J.P.T.).
authors.forename: Alan G
authors.initials: AG
authors.lastname: Jardine
authors.affiliation: From Institute of Cardiovascular and Medical Sciences, University of Glasgow, Glasgow, United Kingdom (E.P.M., A.H.T., E.M.F., A.G.J., P.B.M.); The Glasgow Renal and Transplant Unit, Western Infirmary, Glasgow, United Kingdom (E.P.M., A.H.T., J.G.F., A.G.J., P.B.M.); and Renal Unit, Monklands Hospital, Airdrie, United Kingdom (J.P.T.). patrick.mark@glasgow.ac.uk.
authors.forename: Patrick B
authors.initials: PB
authors.lastname: Mark
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000419:Albuminuria / Q000150:complications / Q000401:mortality / Q000652:urine*; D003404:Creatinine / Q000652:urine*; D018450:Disease Progression; D005260:Female; D006801:Humans; D007668:Kidney / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000150:complications / Q000401:mortality* / Q000652:urine*; D012964:Sodium / Q000652:urine*
chemical_list: D012964:Sodium; D003404:Creatinine
keywords: Renal Insufficiency; diet; hypertension; mortality; sodium