Under-utilization of capillary glucose monitoring by type 2 diabetic patients

Postprandial glycemic excursions contribute significantly to A1C level. Furthermore, postprandial plasma glucose (PPG) is an independent risk factor for cardiovascular disease. We have evaluated the frequency of monitoring and the level of PPG in type 2 diabetic patients followed by their family physician.

Canadian multicenter observational study, including 185 type 2 diabetic patients. Capillary blood glucose was measured with an Ultrasmart glucose meter (Life Scan) during a routine visit to their general practitioner. The patients also had to answer a questionnaire concerning the time since their last meal before the visit, and the frequency of postprandial monitorings defined as

Twenty six percent of patients were treated with diet and exercise alone (Group 1; n=48), 58.4% with oral agents (Group 2; n=108), and 14% with insulin (Group 3; n=26); 1.6% did not know their treatment. The proportion of patients checking their PPG, at least once during the last 15 days was 16.7% (n=8) for Group 1, 37% (n=40) for Group 2 and 46.2% (n=12) for Group 3. The means (S.D.) of PPG were 8.7 mmol/L (3.5), 10.0 (3.7) and 12.7 (4.8) for Groups 1-3, respectively. Based on the Canadian Diabetes Association recommendations for PPG targets, only 36.2% had a good control (<8 mmol/L) while 41.6% had a poor control of their PPG (>10 mmol/L). A PPG >10 mmol/L was found in 18.8% (n=9), 43.5% (n=47) and 73.1% (n=19) of patients in Groups 1-3, respectively. Independent of treatment category, the mean (S.D.) PPG measured by capillary methods was above the recommended target: 10.6 mmol/L (3.7) <1-h postprandial; 10.0 mmol/L (4.2) between 1 and 2h postprandial meal; and 9.9 (3.9) 2 and 3h after meal.

This observational study shows that a third of the patients measured their PPG and for those who did, only a third were within the recommended target. It suggests that the patients, and probably the treating physicians, are not aware of the importance of measuring PPG. Continued medical education strategies are required to implement the recommendations for measuring and treating PPG as part of the intensive treatment of diabetes.