The inter-arm difference in systolic blood pressure is a novel risk marker for subclinical atherosclerosis in patients with type 2 diabetes

Recent studies have suggested that the inter-arm blood pressure difference (IAD) is associated with cardiovascular events and mortality. The aim of this study was to assess whether the IAD could be a marker for subclinical atherosclerosis in patients with type 2 diabetes who are at high risk of cardiovascular disease (CVD). In a cross-sectional retrospective study of 206 Japanese patients with type 2 diabetes aged 49-76 years, we examined the correlation of the IAD with the carotid intima-media thickness (IMT), ankle-brachial index (ABI) or cardio ankle vascular index (CAVI). The IAD was positively correlated with the maximum IMT (r = 0.266, P<0.0001), mean IMT (r = 0.209, P = 0.00726) or CAVI (r = 0.240, P = 0.0005). The IAD was higher in patients with CVD than in those without (P = 0.0020). A multiple linear regression analysis demonstrated that the IAD was an independent determinant of maximum IMT (beta = 0.169, P = 0.0167), mean IMT (beta = 0.178, P = 0.0153), ABI (beta = -0.222, P = 0.0033) or CAVI (beta = 0.213, P = 0.0011) after adjusting for known risk factors. The area under the receiver operating characteristic curve (AUC) of the IAD as a predictor of subclinical atherosclerosis was similar to the AUC of the Framingham 10-year coronary heart disease risk score. In conclusion, the IAD could be a novel risk marker for subclinical atherosclerosis in patients with type 2 diabetes.