Isolated post-challenge hyperglycemia in patients with normal fasting glucose concentration exaggerates neointimal hyperplasia after coronary stent implantation.

Postprandial hyperglycemia has been shown to increase the risk of cardiovascular disease as much as overt diabetes mellitus does. The aim of this study was to determine whether isolated post-challenge hyperglycemia during an oral glucose tolerance test (OGTT) is related to exaggerated neointimal proliferation after coronary stent implantation. Forty seven coronary lesions treated with stents in 40 patients who had normal fasting glucose levels (<110 mg/dl) were categorized into the following 2 groups according to the results of a 75-g OGTT: 29 lesions in 24 patients with normal glucose tolerance (NGT group) and 18 lesions in 16 patients with abnormal glucose tolerance (AGT group). Although there were no differences in angiographic characteristics before and immediately after stenting between the 2 groups, the minimal lumen diameter was significantly smaller (p=0.04) and the degree of stenosis and late loss were also significantly greater (p=0.01 and p=0.047) in the AGT group than in the NGT group at 6-month follow-up. Multiple regression analysis including the insulin concentrations during an OGTT revealed that the 120-min plasma glucose concentration after glucose load significantly correlated with late loss (p=0.0018) and the degree of stenosis (p=0.0100) at follow-up. It is concluded that isolated post-challenge hyperglycemia exaggerates neointimal hyperplasia after coronary stent implantation.