Experts have condemned the £100 million in NHS funds spent each year on self-monitoring kits for type-2 diabetics, which have no apparent benefit and could even cause harm.

There seems to be little point in type-2 diabetics who are not reliant on insulin keeping track of their blood glucose, according to two UK studies published by the BMJ last week.

The first, conducted in County Londonderry, showed self-testing had no benefit for blood glucose control or the risk of hypoglycaemia. The only effect self-testing seemed to have on the 184 participants was to leave them feeling depressed and anxious.

A second trial involving 453 type-2 diabetics randomly assigned to standard care or glucose monitors for 12 months also found self-monitoring to be a waste of money.

Self-monitoring kits cost around £90 extra per patient per year. But no significant difference was found between the groups, even if given training in how to interpret the results.

The debate over the pros and cons of self-testing in non-insulin using type-2 diabetics has been going on for the past 10 years. But this is the first evidence that rather than at worst acting as a benign placebo, self-testing holds potential harms, points out Professor Martin Gulliford, a public health expert at King's College London.

In an accompanying editorial, he suggests that with up to 4 per cent of the UK population affected with diabetes, the costs could exceed £100 million a year.

'This represents a substantial opportunity cost in terms of alternative interventions that might have improved the health of people with diabetes,' Professor Gulliford said.

But Professor Mike Kirby, GP and academic at the University of Hertfordshire, said that for some type-2 diabetics, blood glucose monitoring in the short-term can help them regulate their food intake.

'There shouldn't be a general rule, it should be up to the skill of the doctor,' he said. 'Many patients with type-2 diabetes want to know what happens when they have Sunday lunch.'

Nevertheless, he added: 'It would be foolish to ask nervous or depressed patients to do it because we would be likely to be make it worse.'

rachel.liddle@haymarket.com

BMJ Online 2008

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