Effects of prandial versus fasting glycemia on cardiovascular outcomes in type 2 diabetes: the HEART2D trial

Abstract

Objective: Hyperglycemia and Its Effect After Acute Myocardial Infarction on Cardiovascular Outcomes in Patients With Type 2 Diabetes Mellitus (HEART2D) is a multinational, randomized, controlled trial designed to compare the effects of prandial versus fasting glycemic control on risk for cardiovascular outcomes in patients with type 2 diabetes after acute myocardial infarction (AMI).

Research design and methods: Patients (type 2 diabetes, aged 30-75 years) were randomly assigned within 21 days after AMI to the 1) prandial strategy (PRANDIAL) (three premeal doses of insulin lispro targeting 2-h postprandial blood glucose <7.5 mmol/l) or the 2) basal strategy (BASAL) (NPH twice daily or insulin glargine once daily targeting fasting/premeal blood glucose <6.7 mmol/l).

Results: A total of 1,115 patients were randomly assigned (PRANDIAL n = 557; BASAL n = 558), and the mean patient participation after randomization was 963 days (range 1-1,687 days). The trial was stopped for lack of efficacy. Risks of first combined adjudicated primary cardiovascular events in the PRANDIAL (n = 174, 31.2%) and BASAL (n = 181, 32.4%) groups were similar (hazard ratio 0.98 [95% CI 0.8-1.21]). Mean A1C did not differ between the PRANDIAL and BASAL groups (7.7 +/- 0.1 vs. 7.8 +/- 0.1%; P = 0.4) during the study. The PRANDIAL group showed a lower daily mean postprandial blood glucose (7.8 vs. 8.6 mmol/l; P < 0.01) and 2-h postprandial blood glucose excursion (0.1 vs. 1.3 mmol/l; P < 0.001) versus the BASAL group. The BASAL group showed lower mean fasting blood glucose (7.0 vs. 8.1 mmol/l; P < 0.001) and similar daily fasting/premeal blood glucose (7.7 vs. 7.3 mmol/l; P = 0.233) versus the PRANDIAL group.

Conclusions: Treating diabetic survivors of AMI with prandial versus basal strategies achieved differences in fasting blood glucose, less-than-expected differences in postprandial blood glucose, similar levels of A1C, and no difference in risk for future cardiovascular event rates.

Figure 1

Fraction of patients who did not experience a first primary (combined cardiovascular) adjudicated outcome versus days in trial by treatment strategy (PRANDIAL versus BASAL).

Figure 2

Glycemic measures. A: Mean ± SD A1C at each visit by treatment strategy (PRANDIAL versus BASAL). B: Seven-point mean self-monitored blood glucose profiles at baseline (dotted line) and throughout the study (postrandomization, solid line) by treatment strategy (PRANDIAL versus BASAL).