Asia Pacific Journal of Clinical Nutrition · Jan 22, 2026

Serum albumin and hypertension: The mediating roles of BMI, C-reactive protein and extracellular fluid

By Wang Y, Hao H, Lu Q et al.

UNLABELLED: The relationship between serum albumin and hypertension has attracted much attention. We sought to further validate these findings and explore the underlying mediators. METHODS AND STUDY DESIGN: This cross-sectional study utilized data from the National Health and Nutrition Examination Survey (NHANES 1999-2004), including 19,507 participants. Multivariable weighted logistic were employed to investigate the association of serum albumin with hypertension. The potential mediating role of body mass index (BMI), C-reactive protein (CRP), and extracellular fluid (ECF) was explored. Secondary analyses included subgroup analyses and restricted cubic spline (RCS). RESULTS: Serum albumin per 1 g/L increase was associated with 10% lower hypertension prevalence (OR=0.90, 95%CI:0.89-0.91, p <0.001). This remained significant after full adjustment (including age, sex, race/ethnicity, education level, smoking status, drinking status, sodium in-take, potassium intake, fat intake, total saturated fatty acids [TSFA] intake, carbohydrate intake, protein in-take, energy intake, diabetes, coronary heart disease, creatinine, alanine aminotransferase [ALT], and NHANES cycle)(OR = 0.98, 95%CI: 0.96-1.00, p = 0.031). No evidence of non-linearity was observed in the RCS analysis (p for non-linearity = 0.708). BMI mediated 42.75% (95%CI: 38.19%-48.33%), CRP 12.24% (95%CI: 9.29%-15.43%), and ECF 4.05% (95%CI: 2.74%-5.43%) of the association (all p <0.001). Results were robust in sensitivity analyses. CONCLUSIONS: The serum albumin levels were negatively associated with the prevalence of hypertension. Mediation analyses demonstrated a significant mediating effect of BMI, CRP and ECF, suggesting that serum albumin might be related to hypertension, potentially mediated by BMI, ECF, and CRP.

doi.org/10.6133/apjcn.202602_35(1).0006 Open access PubMed 41565232 Populations