Blood testing used in screening for those at risk of developing type 2 diabetes may be inaccurate, and unlikely to be effective in preventing the condition, a study in the BMJ has found.
Researchers from Oxford University reviewed the results of 49 studies of screening tests, as well as a further 50 intervention trials to discern the efficacy of the NHS Diabetes Prevention Programme. They found that testing HbA1c is ‘neither sensitive nor specific for detecting pre-diabetes’ while measuring fasting glucose is specific but not sensitive. The researchers also found, however, that interventions in people with pre-diabetes detected by the screening are sometimes effective in preventing or delaying onset of type 2 diabetes.
‘Because of the low accuracy of screening tests and the limited reach of intervention programmes, policymakers might want to consider supplementing screen and treat policies with population based approaches aimed at entire communities,’ the authors commented.
The NHS Diabetes Prevention Programme started in 2016, initially covering 26 million people, with total population coverage expected by 2020. Patients referred by the programme received customised help to reduce their risk of developing type 2 diabetes, such as lifestyle advice and support to exercise more regularly.
‘The Diabetes Prevention Programme offers evidence based interventions to delay or prevent onset of Type 2 diabetes in those already identified to be at high risk,’ said Jonathan Valabhji, NHS England's national clinical director for obesity and diabetes. ‘As this BMJ paper highlights, such lifestyle interventions have been clearly shown to work. The NHS is not willing to sit idly by while these individuals progress to Type 2 diabetes.’