ADDITION: No significant benefit of intensive therapy in diabetes
Griffin said the study "was pragmatic and relevant to everyday general practice" and shows that "intensive treatment in people with screen-detected diabetes is feasible" in primary care. The lack of a significant effect of the intensive intervention on the primary end point was likely the result of the great improvements in the routine care of diabetes over the course of the study in the three countries involved, Denmark, the Netherlands, and the UK, he commented.
"Even in the routine-care group that did not receive significant additional support, cardiovascular risk factors improved in the five years following detection by screening. Our intervention to promote more intensive treatment was associated with statistically significant but relatively modest differences in prescribed treatment, in levels of risk factors, and in the proportion of patients for whom treatment targets were achieved. These relatively small differences were in turn associated with a nonsignificant 17% relative reduction in the incidence of a composite CV end point over five years," he told meeting attendees.
Important to note also, said Griffin, was the fact that maintaining average glycated hemoglobin (HbA
1c) levels of 6.5% in the intensive-treatment arm of the study was not associated with any increased mortality risk. This is seen as particularly important in the wake of the
ACCORD results, a trial in which intensive glucose lowering appeared to increase mortality.
Commentators applauded the ADDITION trial, which they noted must have been very difficult to carry out. The invited discussant,
Dr William H Herman (University of Michigan, Ann Arbor), explained that all prior studies of this nature have been observational, and this was research that "I personally believed would never be performed." ADDITION demonstrates that primary-care-based stepwise screening for type 2 diabetes "is feasible and identifies patients with substantial levels of cardiovascular risk that is potentially modifiable," said Herman.
