Abstract 5156: Plasma Des-acyl Ghrelin, but Not Plasma HMW Adiponectin, is a Useful Cardiometabolic Marker for Predicting Atherosclerosis in Elderly Hypertensive Patients
Objective: The coming obesity epidemic in elderly persons necessitates the establishment of new and easy-to-use cardiometabolic markers to identify individuals most likely to develop atherosclerosis among elderly hypertensive patients.
Methods: We measured plasma high-molecular-weight (HMW) adiponectin and des-acyl ghrelin levels, and carotid artery intima-media thickness (cIMT) in 263 elderly hypertensive patients (mean 72.6 years; 37% men). Other cardiometabolic markers, including lipid and glucose metabolites, inflammation (high-sensitivity C-reactive protein: hs-CRP), and hemostasis (plasminogen activator inhibitor-1: PAI-1), were also measured.
Results and conclusion: Both HMW adiponectin and des-acyl ghrelin levels were inversely correlated with obesity (both P<0.01). The HMW adiponectin level was favorably associated with glucose and lipid metabolites, PAI-1(all P<0.05), and hs-CRP (P<0.07) after adjustment for age, sex, and BMI; however, it had no correlations with cIMT. In contrast, although there were no correlations between des-acyl ghrelin and any cardiometabolic markers, except for a positive association with the nitrite/nitrate (NOx) level (P=0.002), des-acyl ghrelin had a significant inverse correlation with cIMT (P=0.003). A multivariable regression analysis showed that des-acyl ghrelin, but not HMW adiponectin, was significantly associated with cIMT after adjusting for age, obesity, sex, smoking, 24-hour BP, and other cardiometabolic factors (β=−0.178, P=0.001). Moreover, receiver-operator curves to predict a high level of cIMT (above median) demonstrated that des-acyl ghrelin was the best predictor (area under the curve=0.622, P=0.001). The increased risk of cIMT among those with abdominal obesity compared with non-obesity (0.833±0.185mm vs. 0.782±0.163mm, P=0.019) was explained by the elevated 24-hour BP and reduced des-acyl ghrelin level, but not by other cardiometabolic parameters. These associations were unchanged after adding NOx to the model. In conclusion, the des-acyl ghrelin level is a useful cardiometabolic marker for predicting atherosclerosis in elderly hypertensive patients, and the pathologic pathway linking these factors is independent of its NO bioactivity.