Ryutaro Numaguchi, Tomoaki Morioka, Yuko Yamazaki, Satoshi Imamura, Hiromi Urata, Koka Motoyama, Katsuhito Mori, Katsuhito Mori, Shinya Fukumoto, Tetsuo Shoji, Masanori Emoto and Masaaki Inaba
Objective: Besides its major role in the regulation of food intake and energy expenditure, leptin is involved in the pathogenesis of obesity-associated atherosclerosis. However, the clinical association between leptin and arterial stiffness, a surrogate marker for cardiovascular disease, has not been fully elucidated. This study aimed to investigate the association between the plasma leptin level and arterial stiffness in patients with type 2 diabetes.
Methods: Three hundred eighteen patients with type 2 diabetes, of which 155 were overweight (body mass index ≥ 25 kg/m2), were included in this study. Fasting plasma leptin levels were measured by enzyme-linked immunosorbent assay. Stiffness of the common carotid artery was evaluated by ultrasonography using Peterson’s elastic modulus (Ep) and arterial compliance (AC). Aortic stiffness was assessed by measuring the pulse wave velocity (PWV) in the heart-femoral segment.
Results: The mean age, duration of diabetes, and body mass index of the subjects were 60 years, 6 years, and 25.4 kg/m2, respectively. Plasma leptin levels were higher in the overweight group than in the lean group (median, 5.8 vs. 2.4 ng/mL). Multiple regression analyses adjusted by age, sex, body mass index, and other cardiovascular risk factors revealed that the plasma leptin level was independently associated with carotid Ep and AC in the overweight group, but not in the lean group. The plasma leptin level was not independently associated with aortic PWV in either group.
Conclusion: The plasma leptin level is associated with carotid arterial stiffness in overweight type 2 diabetes patients, independently of obesity and traditional cardiovascular risk factors. This study indicates an unfavorable effect of leptin on carotid arterial stiffness in diabetes with obesity.