Is higher sodium intake associated with elevated systemic inflammation? A population-based study.
BACKGROUND
Observational epidemiologic studies have suggested that a low-sodium diet is associated with reduced mortality.


OBJECTIVE
The objective was to test the hypothesis that a higher dietary intake of sodium is associated with increased systemic inflammation--a potential risk factor for both cardiovascular disease and cancer.


METHODS
The study design consisted of a randomly selected, cross-sectional, population-based study of 2633 individuals surveyed in 1991, of whom 1597 participants provided paired urinary and blood samples permitting measurement of 24-h urinary sodium excretion and serum C-reactive protein (CRP) concentrations.


RESULTS
The mean (+/-SD) 24-h sodium intake for the population was 177 +/- 69 mmol. In the basic model adjusted for age, sex, and smoking, higher levels of 24-h sodium excretion were directly associated with serum CRP, with an increase in serum CRP of 1.20 mg/L per 100-mmol increment in sodium excretion (95% CI: 1.11, 1.30). However, this association was reduced after adjustment for body mass index, with an increase in serum CRP of 1.06 mg/L per 100-mmol increment in sodium excretion (95% CI: -1.02, 1.15).


CONCLUSIONS
We observed a linear association between an objective measure of sodium intake and serum CRP that may be influenced by confounding by body mass index. The magnitude of these associations suggests that dietary sodium consumption is unlikely to be an important modifiable risk factor for increased systemic inflammation.
Fogarty
Andrew W
AW
Division of Epidemiology and Public Health, University of Nottingham, Clinical Sciences Building, City Hospital, Nottingham, United Kingdom. andrew.fogarty@nottingham.ac.uk
Lewis
Sarah A
SA
McKeever
Tricia M
TM
Britton
John R
JR
D000328:Adult; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism*; D015986:Confounding Factors, Epidemiologic; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007249:Inflammation / Q000209:etiology* / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012964:Sodium / Q000008:administration & dosage* / Q000652:urine; D012982:Sodium, Dietary / Q000008:administration & dosage*
D012982:Sodium, Dietary; D002097:C-Reactive Protein; D012964:Sodium