The glucose-lowering arm of ACCORD was stopped early after an increased risk of cardiovascular and all-cause mortality was identified, while the blood pressure- and lipid-lowering arms continued for another year. Four years after study close (8 years after randomisation), the effect of intensive control on mortality had diminished but remained significant.
However, in a subset of 2856 participants who underwent eye examination throughout the study, intensive glycaemic control was found to reduce the risk of diabetic retinopathy progression compared with standard treatment (5.8% vs. 12.7%; adjusted odds ratio, 0.42; P<0.001). This was despite the fact that HbA1c levels had equalised since the close of the study. Intensive blood pressure control had no significant effect. While fenofibrate was found to have beneficial effects compared with placebo (both in combination with simvastatin) during the active part of the study, the effects did not persist once fenofibrate was discontinued.
Notably, the participants had a diabetes duration of around 10 years at enrolment, and ACCORD is the first study to show that intensive glycaemic control can have a legacy effect even in people with a relatively long duration of type 2 diabetes, with positive long-term effects now reported in terms of retinopathy, neuropathy and nephropathy. However, these benefits need to be weighed against the increased mortality risk. The study also suggests that fenofibrate treatment may need to be ongoing to maintain benefit, although the authors state that further study is required to confirm this.
The full results, first presented at the American Diabetes Association 2016 Scientific Sessions, can be read in Diabetes Care here.
