Association of the urinary sodium to urinary specific gravity ratio with metabolic syndrome in Korean children and adolescents: The Korea National Health and Nutrition Examination Survey 2010-2013

Abstract

ObjectivesThis study aimed to evaluate the association between sodium intake and metabolic syndrome (MetS) in Korean boys.MethodsA total of 1,738 boys aged 10–18 years were included in this study from the Korea National Health and Nutrition Examination Survey (KNHANES) during the years 2010–2013. Sodium intake was assessed using the urinary sodium excretion to urinary specific gravity ratio (U-Na to U-SG ratio).ResultsThe median U-Na to U-SG ratio was 133.27 mmol/L (interquartile range: 95.66–178.50 mmol/L). Significant positive associations were found between the U-Na to U-SG ratio and the TG (P = 0.001 for trend) and TG concentrations, and these concentrations were significantly higher in boys with a U-Na to U-SG ratio in the highest quartile compared with those with a ratio in the lowest (P = 0.001) and second (P = 0.033) quartiles, as demonstrated through analysis of covariance (ANCOVA) after adjustment for possible confounders, including age, BMI standard deviation score, ferritin, vitamin D, house income, smoking, alcohol intake, physical activity, season, total intake, total energy intake, protein intake, fat intake, carbohydrate intake, and water intake. Significant inverse associations were found for the U-Na to U-SG ratio with the HDL-C (P = 0.033 for trend) and HDL-C levels, and these values were significantly lower in boys with a ratio in the highest quartile compared with those with a ratio in the second quartile (P = 0.020), as demonstrated through an ANCOVA. Although the trends did not reach statistical significance, a higher U-Na to U-SG ratio tended to be associated with higher SBP (P = 0.086 for trend), DBP (P = 0.063 for trend), and glucose levels (P = 0.099 for trend), as illustrated through ANCOVA. Boys with a ratio in the highest quartile exhibited a 1.73-fold increased risk for elevated TG (95% CI, 1.19–2.51) and a 2.66-fold increased risk for MetS (95% CI, 1.11–6.35) compared with those with a ratio in the lowest quartile, as demonstrated through multivariate logistic regression analyses after adjusting for confounders.ConclusionsOur results suggest that high sodium intake may be significantly independently associated with MetS in Korean boys aged 10–18 years.

Carbohydrate and sodium intake and physical activity interact with genetic risk scores of four genetic variants mainly related to lipid metabolism to modulate metabolic syndrome risk in Korean middle-aged adults

“…Koreans consume high CHO (average 70•3 En%) and Na (average 5000 mg/d) compared with non-Asians (27) . High CHO and Na intakes are known risk factors for the MetS in Asians including Koreans (28)(29)(30)(31) . Na and CHO intakes interacted with the GRS of the selected SNP in the present study.…”

Analysis of the dietary factors associated with suspected pediatric nonalcoholic fatty liver disease and potential liver fibrosis: Korean National Health and Nutrition Examination Survey 2014-2017

“…Children with suspected NAFLD had higher U-Na-to-SGU ratios and cholesterol intake than healthy controls. High dietary sodium intake is a well-known risk factor for metabolic syndrome and hypertension [21,42,43], and even NAFLD in the adult population [18,19,44]. However, data on the association between sodium intake and pediatric NAFLD are lacking.…”

“…Furthermore, an applicable formula for estimating 24-h urinary sodium excretion in children is unavailable. Based on other studies, we used the U-Na-to-SGU ratio as a surrogate marker of sodium intake [21,36,37].…”

“…However, a 24-h urine sample is difficult to collect, and the cost is relatively expensive. One method for measuring sodium intake is a spot urine sodium level calculated from the urinary sodium (U-Na) levels corrected by specific gravity (SG) or the urinary creatinine level [21,36,37]. In the present study, we used the calculated parameter (SG − 1) × 100 as an SG unit (SGU) [21,36,37].…”

“…Sodium intake positively correlates with metabolic syndrome and hypertension in children, adolescents and adults [21][22][23]. One study revealed an independent association between high sodium intake and an increased risk of NAFLD and advanced liver fibrosis in healthy Korean adults [19].…”