Abstract
Age-related leaky gut is hypothesized to be causative for the inflammatory burden of older adults. A relationship between the leaky gut biomarkers and physical function has been observed in healthy older adults, however it is not known whether co-morbid conditions alters this connection. Therefore, we measured biomarkers of inflammation and leaky gut within a cohort of older patients (60–79 years of age; n=288) enrolled into a weight loss and lifestyle intervention study (CLIP-1). Circulatory lipopolysaccharide binding protein 1 (LBP-1), soluble cluster of differentiation (sCD)14, pro-inflammatory cytokines were measured along with a panel of physical function measures. LBP-1 was strongly associated with increases in inflammatory cytokines interleukin (IL)-6, IL-6 soluble receptor, and IL-8 levels in the unadjusted correlation analysis. sCD14 associations were not as strong thus we chose LBP-1 in regression analyses. LBP-1 and inflammatory outcomes remained significantly associated even after adjustment for age, gender, and body mass index (BMI). LBP-1 was also significantly related to physical functional measures after adjusting for age, gender, and BMI. Log transformed 400m walk time (p=0.003) and log transformed IL-8 levels (p<0.001) were positively associated with LBP-1 even when adjusted for baseline IL-6 levels. The lifestyle interventions resulted in improved BMI and some physical function measures, however biomarkers of leaky gut and inflammation did not change. Leaky gut remains an important factor in inflammatory burdens and physical function in older adults with comorbid conditions. Strategies other than weight loss and exercise are needed to improve gut barrier function and limit inflammation in older persons.