- The Diabetes Control and Complications Trial and UKPDS trial have confirmed the importance of normoglycaemia for preventing diabetic complications.
- Self-monitoring of blood glucose, hailed as a vitally important development in diabetes management, costs the NHS more than £120 million each year (Diabet Med 2005; 22: 511-2).
- The role of self-monitoring for patients with type-2 diabetes who are not receiving insulin is still highly debatable.
What is the evidence?
- Some observational studies have shown that, in patients treated by diet alone, an increased frequency of self-monitoring is associated with better outcomes, including HbA1c and mortality (Diabetes Care 2003; 26: 1,759-63).
- These results may merely indicate that those who are highly motivated (reflected in the take-up of self-monitoring of blood glucose) are likely to do well in the long term.
- In a large study of non-insulin-treated type-2 diabetic patients, the performance and frequency of self-monitoring did not predict better control over a three-year period (Diabet Med 2005; 22: 900-6).
- A quality systematic review following Cochrane methodology identified six relevant randomised controlled trials that fulfilled their predetermined quality standards (Diabetes Care 2005; 28; 1,510-7). The overall effect seen in these trials was that self-monitoring lowered HbA1c by 0.39 per cent, which the authors felt was a clinically significant benefit.
- An Australian study revealed no significant differences in HbA1c levels between those who did home monitoring and those who did not (Diabetes Care 2006; 29: 1,764-70).
Available guidelines/further reading
- NICE has supported the use of self-monitoring in type-2 diabetes, although it indicated that this should only be taught as part of 'integrated self-care' and 'if the purpose ... is agreed with the patient'.
- One small study has demonstrated that patients with type-2 diabetes who use an internet-based glucose-monitoring system have lower HbA1c levels and better glucose control compared with those receiving usual management. However, the internet-based system involved endocrinologists, a nurse and a dietician monitoring the results on a daily basis (Diabetes Care 2006; 29: 2,625-31).
NICE - www.nice.org.uk
Diabetes UK - www.diabetes.org.uk
Dr Louise Newson is a GP in the West Midlands and author of 'Hot Topics for MCRGP and General Practitioners' PasTest 2006
- The role of SMBG is still uncertain for patients with type-2 diabetes.
- Regular HbA1c testing may be equally effective.
- Studies show conflicting results.