Serum albumin levels negatively linked to onset of hypertension

Serum albumin may indirectly reduce the risk of hypertension by regulating obesity, inflammatory status, and fluid balance, suggests a study. 

A group of researchers conducted this cross-sectional study using data from the National Health and Nutrition Examination Survey (NHANES 1999-2004), which included a total of 19,507 participants. They explored the relationship between serum albumin and hypertension using multivariable weighted logistic regression. 

The researchers also examined the potential mediating role of BMI, C-reactive protein (CRP), and extracellular fluid (ECF). Secondary analyses were also conducted, including subgroup analyses and restricted cubic spline (RCS). 

Each 1-g/L increase in serum albumin correlated with 10-percent lower hypertension prevalence (odds ratio [OR], 0.90, 95 percent confidence interval [CI], 0.89‒0.91; p<0.001). [Asia Pac J Clin Nutr 2026;35:60-70] 

This association persisted after adjusting for age, sex, race/ethnicity, education level, smoking status, drinking status, sodium intake, potassium intake, fat intake, total saturated fatty acids (TSFA) intake, carbohydrate intake, protein intake, energy intake, diabetes, coronary heart disease, creatinine, alanine aminotransferase, and NHANES cycle (OR, 0.98, 95 percent CI, 0.96‒1.00; p=0.031). 

Nonlinearity was not observed in the RCS analysis (p=0.708 for nonlinearity). 

Notably, the association between serum albumin and hypertension was significantly mediated by BMI (proportion of mediation [PoM], 42.75 percent, 95 percent CI, 38.19‒48.33), CRP (PoM, 12.24 percent, 95 percent CI, 9.29‒15.43), and ECF (PoM, 4.05 percent, 95 percent CI, 2.74‒5.43; p<0.001 for all). 

The results were consistent in sensitivity analyses. 

“[These findings] provided a new perspective on the prevention and treatment of hypertension,” the researchers said. 

Biochemical marker 

Earlier studies have also shown the associations of BMI, ECF, and CRP with serum albumin levels, as well as with the prevalence of hypertension. 

“Serum albumin serves as a key biochemical marker of nutritional status and is synthesized exclusively in the liver. An appropriately elevated level of serum albumin may be a positive sign of adequate nutritional status and healthy liver function,” the researchers said. [Maturitas 2015;81:17-27] 

“Through metabolic regulation, it mitigates adipose tissue accumulation (resulting in lower BMI), helps maintain plasma osmotic pressure (reducing ECF expansion), and suppresses inflammatory responses (decreasing CRP concentrations),” they added. [Clin Biochem 2023;120:110654; Nephrol Dial Transplant 1998;13:393-397; Am J Med 2020;133:713-22.e7] 

Prior studies have also documented the association between blood pressure values and BMI, which varies depending on age, sex, race, and type of obesity. [J Hum Hypertens 2019;33:123-130; Nutr Metab Cardiovasc Dis 2001;11:344-353] 

Furthermore, growing evidence suggests that elevated ECF volume (fluid overload) has an impact on the pathophysiology of hypertension. This indicates the role of ECF reduction in hypertension control. [J Am Heart Assoc 2018;7:e010278; Am J Nephrol 2023;54:200-207] 

Finally, experimental investigations have demonstrated the active and direct role of CRP in the development of elevated blood pressure. [J Hum Hypertens 2014;28:410-415] 

“These findings are consistent with our conclusions, emphasizing the importance of incorporating BMI, ECF, and CRP into strategies for the early prevention and management of hypertension,” the researchers said.