Lead researcher Dr Simon Griffin told GP there was now a ‘strong case for prescribing metformin from diagnosis’.
He said GPs were reluctant to prescribe anti-diabetic medicines in first-line care because patients detected by screening are often asymptomatic.
Dr Griffin added that there were also ‘erroneous’ concerns that low HbA1c levels are dangerous and the burden of treatment may exceed the burden of disease.
He said: ‘Our data suggest that keeping HbA1c levels low using metformin, in people with low levels to start with as they have been found by screening, is feasible and not harmful.’
In the study, patients’ risk of suffering a cardiovascular event within a decade dropped just 14 months after beginning intensive treatment.
The researchers recruited 867 patients diagnosed with type 2 diabetes by screening at 49 GP surgeries in eastern England. Patients were allocated to receive intensive treatment or routine care.
GPs, nurses and patients in the intensive treatment group were educated about target-driven management of blood glucose, BP and cholesterol.
Patients were treated with medication and advised on lifestyle changes.
After 14 months, routinely treated patients had on average a 31% risk of developing cardiovascular disease in the next 10 years. But those intensively managed saw their risk lowered to 26%.
Researchers attributed the fall to greater use of anti-diabetic drugs, weight loss and decreased energy intake from lifestyle changes.