Association of Type 2 Diabetes and Body Mass Index with Arterial Stiffness: A Carotid Ultrasound Study

Jin Su,1,* Jing Liu,1,* Xiang-Chen Liu,1 Yan Chen,2 Xu Xiao,2 Yuan Zhang,1 Xiu-Ping Lin,1 Yi-Gang Du,3 Yue-Xin Guo,3 Cui-Feng Zhu,4 Xiu-Xia Luo2 1Health Management Center, Shenzhen Hospital of Southern Medical University, Shenzhen, Guangdong, 510086, People’s Republic of China; 2Department of Ultrasound, Shenzhen Hospital of Southern Medical University, Shenzhen, Guangdong, 510086, People’s Republic of China; 3Shenzhen Mindray Bio-Medical Electronics Co., Ltd, Shenzhen, Guangdong, 518052, People’s Republic of China; 4Department of Nutrition, Shenzhen Hospital of Southern Medical University, Shenzhen, Guangdong, 510086, People’s Republic of China*These authors contributed equally to this workCorrespondence: Cui-Feng Zhu, Department of Nutrition, Shenzhen Hospital of Southern Medical University, 1333 Xinhu Road, Bao’an District, Shenzhen, Guangdong, 510086, People’s Republic of China, Tel +86 0755-27897010, Email [email protected] Xiu-Xia Luo, Department of Ultrasound, Shenzhen Hospital of Southern Medical University, 1333 Xinhu Road, Bao’an District, Shenzhen, Guangdong, 510086, People’s Republic of China, Tel +86 13336414336, Email [email protected]: This study aimed to investigate the joint and independent associations of type 2 diabetes (T2DM) and body mass index (BMI) with arterial stiffness using carotid ultrasound-based measures.Methods: This retrospective, matched cross-sectional study enrolled 255 participants, including people with T2DM (n=129) and Control group (diabetes-free, n=126). The control group was matched to the T2DM group based on age (± 5 years), sex, and BMI category. People with T2DM were diagnosed according to World Health Organization criteria and classified into three BMI-based categories: lean (BMI< 25 kg/m2, n=48), overweight (BMI=25– 29.9 kg/m2, n=44) and obese (BMI≥ 30 kg/m2, n=37). Carotid intima-media thickness (IMT) and pulse wave velocity (PWV) were determined using sample images. Univariable and multivariable logistic regression models were used to evaluate the associations between BMI, T2DM and arterial stiffness, adjusted for potential confounders such as age, systolic blood pressure and lipid profiles. Interaction terms tested multiplicative effects.Results: Compared to people with diabetes-free, those with T2DM had significantly greater IMT and PWV impairments (P< 0.001). An increasing BMI category was associated with progressive IMT and PWV increase in people with T2DM (P< 0.001). Multi-variable analysis revealed that BMI category had strong associations with carotid IMT (Standardize β 0.715, 95% CI: 113.4, 174.7) and PWV (Standardize β 0.544, 95% CI: 0.81, 1.73), indicating the progressive impact of BMI on arterial stiffness. No interaction was observed between T2DM and BMI (IMT: P-interaction=0.95; PWV: P-interaction=0.56), indicating independent effects.Conclusion: This study demonstrates additive but non-synergistic effects of T2DM and BMI on arterial stiffness, with BMI driving the majority of vascular impairment. However, the cross-sectional design precludes causal inferences. The findings underscore the clinical relevance of weight management in people with T2DM.Keywords: type 2 diabetes mellitus, obesity, carotid arteries, body mass index, arterial stiffness