Sodium intake and blood pressure among US children and adolescents.

OBJECTIVE

To assess the association between usual dietary sodium intake and blood pressure among US children and adolescents, overall and by weight status.

METHODS

Children and adolescents aged 8 to 18 years (n = 6235) who participated in NHANES 2003-2008 comprised the sample. Subjects' usual sodium intake was estimated by using multiple 24-hour dietary recalls. Linear or logistic regression was used to examine association between sodium intake and blood pressure or risk for pre-high blood pressure and high blood pressure (pre-HBP/HPB).

RESULTS

Study subjects consumed an average of 3387 mg/day of sodium, and 37% were overweight/obese. Each 1000 mg per day sodium intake was associated with an increased SD score of 0.097 (95% confidence interval [CI] 0.006-0.188, ∼1.0 mm Hg) in systolic blood pressure (SBP) among all subjects and 0.141 (95% CI: -0.010 to 0.298, ∼1.5 mm Hg) increase among overweight/obese subjects. Mean adjusted SBP increased progressively with sodium intake quartile, from 106.2 mm Hg (95% CI: 105.1-107.3) to 108.8 mm Hg (95% CI: 107.5-110.1) overall (P = .010) and from 109.0 mm Hg (95% CI: 107.2-110.8) to 112.8 mm Hg (95% CI: 110.7-114.9; P = .037) among those overweight/obese. Adjusted odds ratios comparing risk for pre-HBP/HPB among subjects in the highest versus lowest sodium intake quartile were 2.0 (95% CI: 0.95-4.1, P = .062) overall and 3.5 (95% CI: 1.3-9.2, P = .013) among those overweight/obese. Sodium intake and weight status appeared to have synergistic effects on risk for pre-HBP/HPB (relative excess risk for interaction = 0.29 (95% CI: 0.01-0.90, P < .05).

CONCLUSIONS

Sodium intake is positively associated with SBP and risk for pre-HBP/HPB among US children and adolescents, and this association may be stronger among those who are overweight/obese.