Of an estimated 2.35 million people in England with diabetes, 28 per cent are still undiagnosed, according to DoH figures released last week.
In her report, 'Turning the corner, improving diabetes care', national clinical director for diabetes Dr Sue Roberts says that in the three years since the NSF for diabetes was launched, diabetes care has improved, although more has to be done.
One of the targets set by the NSF, to be met by 2013, is to develop, implement and monitor strategies to identify patients with undiagnosed diabetes.
County Down GP Dr Colin Kenny, chairman of the Primary Care Diabetes Society, said that screening everyone who is over 40 years old, overweight or from an at-risk ethnic minority could identify the 'missing million' with undiagnosed diabetes.
'It is becoming increasingly attractive to initiate a screening programme,' he said. 'The science is there, it's the politicians that are the stumbling block.'
Hopes of a screening programme that considers a range of cardiovascular risk factors, including diabetes, for the over-40s were raised earlier this year at a Diabetes UK conference.
Professor Sir Muir Gray, National Screening Committee programme director, said it could be in use from next year (GP, 7 April).
The DoH has now said it is working closely with the committee to identify the best screening strategy, who will benefit most and cost implications.
Cost remains the largest barrier, Dr Kenny warned. He said that funding would be needed to pay GPs carrying out the screening and for diabetes management.
Dr Shahid Ali, a Bradford GP who has carried out research on diabetes screening in his area, agreed that lack of resources was a serious stumbling block.
'We could screen on a national basis, but without having the capacity or resources to deal with the extra cases, a lot of practices would be reluctant,' he said.
He added that even targeted screening of the over-40s would not pick up all cases since an increasing number of young people were developing type-2 diabetes as obesity rates rise.
The proportion of undiagnosed diabetics in the UK is still below that of the US, however.
DoH report on diabetes
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