Serum Albumin Level Predicts Systemic Arterial Stiffening Mediated Partially by Change in Lean Body Mass: A Retrospective Cohort Study in General Japanese Population.

BACKGROUND AND AIM: Serum albumin level (albumin) is inversely associated with the risk of cardiovascular disease (CVD) mortality. Additionally, the decline in lean body mass partially mediates the age-related vascular dysfunction. We aimed to clarify the interaction between albumin, lean body mass and vascular function in the general Japanese population.

METHODS: This study analyzed three-year longitudinal data (n=5,253) obtained from Japanese urban residents receiving consecutive annual health screenings. Participants with a history of CVD and/or any chronic wasting diseases were excluded. Skeletal muscle mass was assessed using estimated lean body mass index (eLBMI). Systemic arterial stiffness was assessed using the cardio-ankle vascular index (CAVI), with high CAVI defined as CAVI ≥9.0.

RESULTS: Among serum protein parameters, albumin showed a stronger inverse correlation with CAVI (r = -0.191) compared to total protein and albumin/globulin ratio. Age correlated positively with CAVI and negatively with albumin. In multiple regression analysis, 1 standard deviation increase in albumin was negatively associated with high CAVI (odds ratio = 0.78), independent of aging and traditional CVD risk factors. Jonckheere-Terpstra trend test revealed a significant inverse trend in change in CAVI over three years (ΔCAVI) among the stratified baseline albumin groups, whereas no significant trend was observed among the stratified age groups. Baseline albumin was negatively associated with ΔCAVI, which was partially mediated by ΔeLBMI after adjusting for age (mediation rate, 3.4%).

CONCLUSION: As serum albumin level predicts CAVI mediated by changes in lean body mass, appropriate nutrition management aimed at enhancing skeletal muscle mass may be useful for reliable prevention of CVD.