June 25th, 2011
Limited Benefit Found for Early Aggressive Management of Diabetes
In the ADDITION-Europe trial, 3055 patients without diabetes were randomized to either routine care or screening followed by intensive treatment of multiple risk factors. The results were presented at the American Diabetes Association meeting and published online in the Lancet. After five years, cardiovascular risk factors — HbA1c, lipids, and blood pressure — were “slightly but significantly better in the intensive treatment group,” according to the authors. However, the primary endpoint of the study, incidence of the first cardiovascular event, did not differ significantly between the groups, although the difference favored intensive treatment: 7.2% in the intensive-treatment group versus 8·5% in the routine-care group (hazard ratio, 0·83; 95% CI, 0·65–1·05). All-cause mortality was 6·2% versus 6·7% (HR, 0.91; 95% CI, 0·69–1·21).
The authors speculated that the results may be due, in part, to overall improvements in risk factors over the course of the trial, resulting in fewer cardiovascular events than expected. In addition, longer follow-up might be required to demonstrate a significant benefit. The authors concluded that “the extent to which the complications of diabetes can be reduced by earlier detection and treatment remains uncertain.”
In an accompanying comment, David Preiss and Naveed Sattar write that “the emergence of evidence-based standards of routine diabetes care, especially for lipid-lowering and antihypertensive therapies, negated potential benefits of intensive therapy in ADDITION-Europe. The key questions now are whether a sizeable reduction in the lead time between diabetes onset and clinical diagnosis can be achieved by implementation of simpler diagnostic criteria (i.e.,HbA1c) and, if so, to what extent this development might further reduce cardiovascular and mortality risks in patients with diabetes.”