The new consensus statement on the care of hyperglycaemic and diabetic patients with an acute coronary syndrome (ACS) represents a considerable effort to provide clinician cardiologists with guidance in the management of their patients. It is a remarkable achievement.

Several points are of particular importance, on which the consensus provides up-to-date reviews that make an important addition to current literature. Conversely, as in all consensus documents or guidelines, some of the proposed recommendations are undoubtedly debatable, in particular when these are put in the context of current practices in France.

In the first category is the emphasis put on the high prevalence of glucose metabolism disorders in patients with coronary artery disease admitted with an acute coronary event. In recent surveys in France, the prevalence of known diabetes mellitus at the time of an acute myocardial infarction (AMI) is around 20–22% . This figure actually underestimates the true prevalence of diabetes, as it is now widely recognised that, even in France , the proportion of patients without recognised diabetes is high in those presenting with an ACS.

The pathophysiological significance and prognostic importance of hyperglycaemia at the acute stage is also underlined. In brief, all evidence concurs in showing the deleterious prognostic significance of a hyperglycaemic state, which may represent both a true underlying metabolic disorder but also a marker of acute stress and profound myocardial injury. As pointed out in the text, hyperglycaemia has a deleterious prognostic significance, both in patients with and in those without recognised diabetes .

The consensus document also carefully reviews the results of trials having assessed the role of insulin therapy at the acute stage and emphasizes the potential risk of hypoglycaemia in situations of acute myocardial ischaemia.

Finally, the text gives a welcome overview of the benefits of rehabilitation after an acute coronary event, of nutritional counselling, and of when patients should be referred to a diabetologist. All of these points are particularly relevant, and the consensus statement provides a very useful and state-of-the-art review of our current knowledge in this field.

Some of the recommendations, however, may raise questions as they are a long way from current practice in France, and their clinical impact has not been truly assessed in the context of contemporary cardiac care of ACS patients. Two of them are important.

Because of the dual mechanism underlying admission hyperglycaemia, the text justly recommends that admission blood glucose levels should not be used to define the presence or absence of diabetes mellitus. Instead, it proposes that all patients without known diabetes mellitus undergo an oral glucose tolerance test 1–4 weeks after the acute episode. This is extremely far from current practices, and aside from the potential difficulty in organizing such a generalized approach, there is no true evidence that it is clinically warranted. Instead, a simple check of the HbA1c levels both on admission and somewhat later during the follow-up of patients, for instance on the occasion of a more complete work-up including the assay of blood lipids on statin therapy, might be a more realistic approach to detect ‘hidden’ glucose metabolism disorders.

The second recommendation pertains to the systematic use of insulin therapy and to the interruption of all other antidiabetic agents during the stay in the intensive care unit. Again, this is far from real-world practice in France: in the recent FAST-MI 2010 (French Registry of Acute ST-Elevation and Non–ST-Elevation Myocardial Infarction 2010), carried out at the end of 2010 in about three-quarters of the French intensive cardiac care units, only 46% of the patients with an admission glycaemia more or equal to 180 mg/dL and 53% of diabetic patients received early insulin treatment, while most diabetic patients were kept on their current hypoglycaemic medications (personal data). In particular, one wonders what is the rationale for stopping antidiabetic oral medications when admission glycaemia is less than 180 mg/dL, which was the case in over half of the diabetic patients admitted with either ST-elevation myocardial infarction or non-ST-elevation myocardial infarction in the FAST-MI 2010 registry… In fact, the Diabetes Mellitus Insulin Glucose Infusion in AMI (DIGAMI 2) trial–the most recent randomized trial assessing the impact of different glucose-lowering regimens in patients with AMI –failed to show the superiority of routine insulin therapy compared with the continuation of oral antidiabetic agents with provisional use of insulin in patients admitted with AMI; in reality, the group with the best long-term outcome was the one who underwent conventional management, in whom only 14% received insulin at the acute stage.

Likewise, the policy regarding metformin treatment in patients undergoing coronary angiography (about 90% of the patients admitted with AMI in France at the end of 2010) also merits debate. In contrast with the current consensus document, the recent myocardial revascularization guidelines of the European Society of Cardiology/European Association of Cardiothoracic Surgery note that there is little scientific evidence for recommending stopping metformin before coronary angiography/percutaneous coronary intervention (PCI) is performed; it is suggested that in metformin-treated patients, renal function should be carefully monitored after the procedure and metformin should be stopped only when renal function deteriorates; in diabetic patients with renal failure, it is proposed to consider stopping metformin 48 h before the procedure (grade IIb recommendation, level of evidence C). Such an interruption, however, cannot apply to patients undergoing primary PCI, and the benefits of primary PCI should certainly not be denied to diabetic patients on metformin treatment because of a potential risk of lactic acidosis. In fact, the FAST-MI 2005 and FAST-MI 2010 registries show a very low in-hospital mortality in diabetic patients on metformin-treated with primary PCI, and provide extremely reassuring data in this regard (personal data).

Overall, the consensus document is a laudable effort to focus the attention of cardiologists on the importance of glucose metabolism disorders and diabetes mellitus in patients sustaining an acute coronary event. As in all expert consensus documents, some of the measures proposed may be questionable, emphasizing the fact that such documents should be interpreted as general rules that are meant to be adapted to each individual situation.