Postprandial blood glucose predicts cardiovascular events and all-cause mortality in type 2 diabetes in a 14-year follow-up: lessons from the San Luigi Gonzaga Diabetes Study

Abstract

Objective: To evaluate whether postprandial blood glucose predicts cardiovascular events and all-cause mortality in type 2 diabetes in a long-term follow-up taking into account A1C and the main cardiovascular risk factors.

Research design and methods: Consecutive type 2 diabetic patients (n = 505) followed up at our diabetes clinic were evaluated at baseline (1995) for the main cardiovascular risk factors and for five glycemic control parameters (fasting blood glucose, blood glucose 2 h after breakfast, blood glucose 2 h after lunch, blood glucose before dinner, and A1C); all-cause mortality and the first cardiovascular events occurring during the 14-year follow-up were measured.

Results: We observed 172 cardiovascular events (34.1% of the population) and 147 deaths (29.1% of the population). Using the Cox analysis with the backward method, we categorized the variables according to the therapeutic targets of the American Diabetes Association. Our observations were as follows. When the five glycemic control parameters were considered together, the predictors were 1) for cardiovascular events, blood glucose 2 h after lunch (hazard ratio 1.507, P = 0.010) and A1C (1.792, P = 0.002); and 2) for mortality, blood glucose 2 h after lunch (1.885, P < 0.0001) and A1C (1.907, P = 0.002). When blood glucose 2 h after lunch and A1C were considered together with the main cardiovascular risk factors, the following glycemic control parameters were predictors: 1) for cardiovascular events, blood glucose 2 h after lunch (1.452, P = 0.021) and A1C (1.732, P = 0.004); and 2) for mortality, blood glucose 2 h after lunch (1.846, P = 0.001) and A1C (1.896, P = 0.004).

Conclusions: In type 2 diabetes, both postprandial blood glucose and A1C predict cardiovascular events and all-cause mortality in a long-term follow-up.