BackgroundThe carotid artery intima-media thickness (CIMT) has been used as a predictor of cardiovascular events, but it remains unclear whether CIMT can change over the short term. We evaluated changes of CIMT in patients with diabetes during admission to hospital for 2 weeks.MethodsA total of 279 inpatients with diabetes aged 61 ± 14 years were recruited. They were on treatment with insulin and/or oral agents, excluding drugs that influence the fluid balance and hemodynamics. CIMT was measured on the day after admission and on the day before discharge, and the association of ΔCIMT (calculated by subtracting the baseline value from that on the day before discharge) with clinical factors was evaluated.ResultsBased on the reported annual increase of CIMT (0.04 mm/year), the patients were divided into three groups, in which CIMT increased [I: ΔCIMT ≥ 0.04 mm, n = 64, ΔCIMT = 0.077 ± 0.048 (mean ± SD)], CIMT decreased (D: ΔCIMT ≤ −0.04 mm, n = 51, ΔCIMT = −0.090 ± 0.086), or CIMT was unchanged (N: −0.04 mm < ΔCIMT < 0.04 mm, n = 164, ΔCIMT = 0.002 ± 0.022). Binary logistic regression analysis showed that baseline CIMT and hemoglobin (Hb) were positively correlated, while Hb on the day before discharge was negatively correlated, with a decrease of CIMT. In contrast, baseline HbA1c and Hb were negatively correlated, while Hb on the day before discharge was positively correlated, with an increase of CIMT.ConclusionsCIMT may show plasticity in patients with diabetes and can change even after short-term treatment of hyperglycemia for 2 weeks.