Self-Monitoring of Blood Glucose
CADTH Optimal Use Project
Self-monitoring of blood glucose (SMBG) is performed by patients with diabetes mellitus to check the level of glucose in their blood at a given point in time. SMBG can be performed at home, work, or elsewhere — the process involves pricking a fingertip to collect a drop of blood, absorbing the blood with a test strip, and inserting the test strip into an electronic glucose monitor which then displays a number on its screen. SMBG has been advocated for years as an approach to improve glycemic control for people with type 1 and type 2 diabetes.
Need for Recommendations
Despite widespread use, the benefits of SMBG — especially in patients with type 2 diabetes not using insulin — and the optimum frequency of testing has not been defined. Further, costs associated with SMBG are high and rising steadily due to the increasing prevalence of diabetes in Canada and higher rates of self-monitoring.
One of the Canadian Agency for Drugs and Technologies in Health’s (CADTH’s) former advisory committees, the Canadian Optimal Medication Prescribing and Utilization Service (COMPUS) Advisory Committee (representing Canadian health jurisdictions), recommended that we review the clinical and economic evidence relating to the optimal prescribing and use of SMBG. Key research questions included:
- What is the optimal blood glucose testing frequency in patients with type 2 diabetes mellitus?
- What is the optimal blood glucose testing frequency in patients with type 1 diabetes mellitus and in patients with gestational diabetes mellitus?
CADTH’s work on this project has resulted in the following key messages:
- For people with type 1 or type 2 diabetes using basal-bolus insulin regimens, SMBG should be individualized to guide adjustments in insulin therapy.
- In adults with type 2 diabetes using basal insulin, SMBG should be individualized, but testing of up to 14 times per week should suffice in most cases.
- Most adults with type 2 diabetes using oral antidiabetes drugs (without insulin) do not require routine SMBG. Periodic testing may be needed for select patients, such as those with:
- unstable glucose levels
- acute illness
- changes to drug therapy
- risk of hypoglycemia
- jobs where hypoglycemia poses danger.
Periodic testing in these select patients should be linked to specific actions (e.g., prevention or management of hypoglycemia, self-directed dosage adjustment).
- Most adults with type 2 diabetes controlled by diet alone should not require routine SMBG.
For the full recommendations and detailed information on their development, see the recommendations report.
CADTH also offers knowledge mobilization tools to support the implementation of recommendations and to assist health care professionals, policy-makers, and consumers in making well-informed decisions.
Stakeholder feedback was considered at specific stages of this project.