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."
Professor Nick Wareham, UK Medical Research Council Epidemiology Unit, Addenbrooke's Hopsital, Cambridge, UK. T) +44 (0) 7786 682601 E) simon.griffin@mrc-epid.cam.ac.uk
Professor Naveed Sattar British Heart Foundation and Glasgow Cardiovascular Research Centre, University of Glasgow, UK. (attending ADA) T) +44 (0) 7971 189415 E) naveed.sattar@glasgow.ac.uk
Journal
The Lancet