Background: Intestinal (i.e., "gut") permeability may be related to cardiovascular disease (CVD) risk, but biomarkers for gut permeability are limited and associations with CVD risk are unknown-particularly among older adults.
Aims: This cross-sectional study aimed to determine if serum biomarkers related to gut permeability [intestinal fatty acid-binding protein (iFABP)] and bacterial toxin clearing [cluster of differentiation 14 (CD14), lipopolysaccharide binding protein (LBP)] are associated with CVD risk among older adults.
Methods: Older adults (n = 74, 69.6 ± 6.5-years-old) were stratified by CVD risk category. One-way ANOVAs determined differences in each biomarker by risk category, and associations with risk score were evaluated with Pearson correlations.
Results: LBP (p = 0.007), but not iFABP and CD14, was significantly different between CVD risk categories. Post-hoc tests indicated LBP was higher in moderate risk and high-moderate risk compared to the high risk category (p < 0.005). Evaluation of LBP and individual components in the risk score demonstrated a moderate, negative correlation of LBP with age and systolic blood pressure (r = - 0.335 and r = - 0.297) and a small positive correlation between LBP and total cholesterol and LDL cholesterol (r = 0.204 and r = 0.220).
Discussion/conclusion: Lower risk for CVD was associated with higher circulating concentrations of LBP, lower iFABP, and lower systemic inflammation in older adults. Further, there were small positive relationships between total and LDL cholesterol and circulating levels of LBP. These data suggest LBP may be a key component in reducing CVD risk in older adults.
Keywords: Aging; Cardiovascular disease risk; Intestinal permeability; Lipopolysaccharide binding protein.