RESUMO
BACKGROUND: The association between magnesium status and metabolic syndrome remains unclear. This study aimed to examine the relationship between the kidney reabsorption-related magnesium depletion score (MDS) and metabolic syndrome among US adults. METHODS: We analyzed data from 15,565 adults participating in the National Health and Nutrition Examination Survey (NHANES) 2003-2018. Metabolic syndrome was defined according to the National Cholesterol Education Program's Adult Treatment Panel III report. The MDS is a scoring system developed to predict the status of magnesium deficiency that fully considers the pathophysiological factors influencing the kidneys' reabsorption capability. Weighted univariate and multivariate logistic regression were used to assess the association between MDS and metabolic syndrome. Restricted cubic spline analysis was conducted to characterize dose-response relationships. Stratified analyses by sociodemographic and lifestyle factors were also performed. RESULTS: In both univariate and multivariate analyses, higher MDS was significantly associated with increased odds of metabolic syndrome. Each unit increase in MDS was associated with approximately a 30% higher risk for metabolic syndrome, even after adjusting for confounding factors (OR 1.31; 95% CI 1.17-1.45). Restricted cubic spline graphs depicted a linear dose-response relationship across the MDS range. This positive correlation remained consistent across various population subgroups and exhibited no significant interaction by age, gender, race, adiposity, smoking status, or alcohol consumption. CONCLUSIONS: Higher urinary magnesium loss as quantified by MDS may be an independent linear risk factor for metabolic syndrome in US adults, irrespective of sociodemographic and behavioral factors. Optimizing magnesium nutritional status could potentially confer benefits to patients with metabolic syndrome.