No to QOF target of less than 7%, again

A large observational study examining the effect of additional glucose lowering treatment in nearly 28 000 primary care patients with type 2 diabetes in the UK was published last month.1 2 A glycated haemoglobin concentration of 7.5% was associated with the lowest mortality. Concentrations below 7% were associated with a higher mortality—matched only by concentrations above 9%—whether the additional treatment was another oral drug or insulin.

This observational evidence, though not definitive in its own right, is consistent with the interventional evidence suggesting a possibility of harm from lowering glycated haemoglobin below 7% in patients with established type 2 diabetes.3 This evidence, with that of two negative trials, led us in March last year to call for this target to be abandoned in the quality and outcomes framework.4 At this point, it still stands.

Proponents of a target for glycated haemoglobin of under 7% often cite the long term results of the UK prospective diabetes trial, in which tight glycaemic control in the first years after diagnosis of type 2 diabetes seemed to produce cardiovascular benefits many years later.5 However, these subjects did not reach a mean glycated haemoglobin concentration of under 7%.

We in the UK should follow the lead of the National Committee on Quality Assurance in the United States and suspend this target. We cannot risk harm by incentives that encourage practice patterns which the evidence does not support and which may even compromise patient safety.