Associations of decreased serum transthyretin with elevated high-sensitivity CRP, serum copper and decreased hemoglobin in ambulatory elderly women.

Background: Transthyretin (TTR), a sensitive indicator of malnutrition and inflammation, has been shown to be associated with mortality in elderly population.

Methods: We examined relationships between serum TTR and a range of risk factors for mortality in 185 free-living elderly women. Blood was drawn between breakfast and lunch.

Results: TTR was correlated negatively with age (r=-0.30, p<0.001). After controlling for age, TTR was negatively associated with log high-sensitivity CRP (hsCRP) and serum copper. It was positively associated with albumin, serum iron and hemoglobin. In addition, TTR was positively correlated with systolic and diastolic blood pressure and postprandial triglyceride (TG). In multiple regression analysis for TTR as a dependent variable, hemoglobin (standardized β, 0.244), serum copper (standardized β, -0.134), postprandial TG (standardized β, 0.223) and log hsCRP (standardized β, -0.190) emerged as determinants of TTR independently of age, albumin, serum iron, systolic and diastolic blood pressure, and explained 22.8% of TTR variability.

Conclusions: Subclinical low-grade inflammation, elevated serum copper and decreased hemoglobin were associated with decreased serum TTR in community-living elderly Japanese women and may represent important confounders of the relationship between low TTR and mortality in the elderly. The positive association of TTR with postprandial TG warrants further investigation.