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, the first cardiovascular event, was not significantly different between the groups, though the difference favored intensive treatment: 7.2% in the intensive treatment group versus 8·5% in the routine care group (HR 0·83,CI 0·65–1·05). All-cause mortality was 6·2% versus 6·7% (HR 0.91,0·69–1·21).
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 followup might be required to demonstrate a 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 (ie, HbA1c) and, if so, to what extent this development might further reduce cardiovascular and mortality risks in patients with diabetes.”
Here is the Lancet press release:
INTENSIVE MULTIFACTORAL TREATMENT IN DIABETES PATIENTS DETECTED BY SCREENING LEADS TO SMALL, NON-STATISTICALLY SIGNIFICANT DECREASE IN MORTALITY AND CARDIOVASCULAR EVENTS COMPARED WITH USUAL CARE (ADDITION-Europe study)
Screening for undiagnosed diabetes is feasible in primary care and detects people with high and potentially modifiable cardiovascular risk. In new research published Online First by The Lancet (the ADDITION-Europe study) a team of European researchers shows that, in patients diagnosed through screening in general practice, intensive multifactoral treatment leads to small but statistically significant improvements in risk factors compared with usual care. But there was only a small, non-statistically significant reduction in mortality and cardiovascular events (such as heart attack, stroke, and amputation) in intensively treated patients. The Article is by Professor Nick Wareham and Dr Simon J Griffin, UK Medical Research Council Epidemiology Unit, Addenbrooke’s Hopsital, Cambridge, UK, and colleagues.
The study analysed data from 3055 type 2 diabetes patients (1377 in usual care arm, 1678 in intensive treatment arm), mean age 60 years, detected at screening in general practices in the UK, Denmark, and the Netherlands. They found that improvements in cardiovascular risk factors (HbA1c , cholesterol concentrations, and blood pressure) were slightly better (and statistically significant) in the intensive treatment group.
The incidence of first cardiovascular event was 7·2% in the intensive treatment group and 8·5% in the routine care group and of all-cause mortality 6·2% and 6·7%, respectively. But these findings were not statistically significant. The authors say: “When compared with routine care, an intervention to promote target-driven, intensive management of patients with type 2 diabetes detected by screening was associated with small increases in the prescription of drugs and improvements in cardiovascular risk factors, but was not associated with significant reductions in the incidence of cardiovascular events or death over 5 years…The extent to which the complications of diabetes can be reduced by earlier detection and treatment remains uncertain.”
In a linked Comment, Dr David Preiss and Professor Naveed Sattar British Heart Foundation and Glasgow Cardiovascular Research Centre, University of Glasgow, UK, say that the recent recommendations (produced in the last 5 to 7 years) for routine prescribing of statins to lower cholesterol and blood pressure-lowering drugs in usual care for diabetes has limited the potential of more intensive treatment to deliver additional differences in outcomes in this patient group. They conclude: “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 (ie, HbA1c) and, if so, to what extent this development might further reduce cardiovascular and mortality risks in patients with diabetes.”