Self-monitoring of blood glucose in noninsulin-using type 2 diabetic patients: it is time to face the evidence.

Given the importance of glycemic control in the development of diabetes complications, the plethora of tools now available to monitor the day-to-day trends in glycemia is remarkable. In this regard, self-monitoring of blood glucose (SMBG) has been considered a key component of patient management. Arguably, there remains almost universal agreement that SMBG should be available to all diabetic patients regardless of current treatment strategy. However, recently there have been reports that have challenged the current paradigm that all patients should use SMBG and concluded that SMBG for type 2 diabetic patients not on insulin may not be beneficial on glycemic control and must be weighed against the expense and inconvenience. In this two-part point-counterpoint narrative, Malanda et al. and Polonsky and Fisher take opposing views on the utility of SMBG to be valuable for individuals with type 2 diabetes not using insulin. In the narrative below, Malanda et al. suggest that the evidence for potentially beneficial SMBG-induced effects on glycemic control, hypoglycemic periods, and potential harms in type 2 diabetic patients who are not treated with insulin does not justify the use of SMBG. Moreover, the use of SMBG is associated with huge costs, which should be better redirected to effective strategies to improve health for this category of patients. -William T. Cefalu, MD Editor in Chief, Diabetes Care.

Self-monitoring of blood glucose in patients with type 2 diabetes mellitus who are not using insulin.

BACKGROUND: Self-monitoring of blood glucose (SMBG) has been found to be effective for patients with type 1 diabetes and for patients with type 2 diabetes using insulin. There is much debate on the effectiveness of SMBG as a tool in the self-management for patients with type 2 diabetes who are not using insulin. OBJECTIVES: To assess the effects of SMBG in patients with type 2 diabetes mellitus who are not using insulin. SEARCH METHODS: Multiple electronic bibliographic and ongoing trial databases were searched supplemented with handsearches of references of retrieved articles (date of last search: 07 July 2011). SELECTION CRITERIA: Randomised controlled trials investigating the effects of SMBG compared with usual care, self-monitoring of urine glucose (SMUG) or both in patients with type 2 diabetes who where not using insulin. Studies that used glycosylated haemoglobin A(1c) (HbA(1c)) as primary outcome were eligible for inclusion. DATA COLLECTION AND ANALYSIS: Two authors independently extracted data from included studies and evaluated the studies' risk of bias. Data from the studies were compared to decide whether they were sufficiently homogeneous to pool in a meta-analysis. Primary outcomes were HbA(1c), health-related quality of life, well-being and patient satisfaction. Secondary outcomes were fasting plasma glucose level, hypoglycaemic episodes, morbidity, adverse effects and costs. MAIN RESULTS: Twelve randomised controlled trials were included and evaluated outcomes in 3259 randomised patients. Intervention duration ranged from 6 months (26 weeks) to 12 months (52 weeks). Nine trials compared SMBG with usual care without monitoring, one study compared SMBG with SMUG, one study was a three-armed trial comparing SMBG and SMUG with usual care and one study was a three-armed trial comparing less intensive SMBG and more intensive SMBG with a control group. Seven out of 11 studies had a low risk of bias for most indicators. Meta-analysis of studies including patients with a diabetes duration of one year or more showed a statistically significant SMBG induced decrease in HbA(1c) at up to six months follow-up (-0.3; 95% confidence interval (CI) -0.4 to -0.1; 2324 participants, nine trials), yet an overall statistically non-significant SMBG induced decrease was seen at 12 month follow-up (-0.1; 95% CI -0.3 to 0.04; 493 participants, two trials). Qualitative analysis of the effect of SMBG on well-being and quality of life showed no effect on patient satisfaction, general well-being or general health-related quality of life. Two trials reported costs of self-monitoring: One trial compared the costs of self-monitoring of blood glucose with self-monitoring of urine glucose based on nine measurements per week and with the prices in US dollars for self-monitoring in 1990. Authors concluded that total costs in the first year of self-monitoring of blood glucose, with the purchase of a reflectance meter were 12 times more expensive than self-monitoring of urine glucose ($481 or 361 EURO [11/2011 conversion] versus $40 or 30 EURO [11/2011 conversion]). Another trial reported a full economical evaluation of the costs and effects of self-monitoring. At the end of the trial, costs for the intervention were £89 (104 EURO [11/2011 conversion]) for standardized usual care (control group), £181 (212 EURO [11/2011 conversion]) for the less intensive self-monitoring group and £173 (203 EURO [11/2011 conversion]) for the more intensive self-monitoring group. Higher losses to follow-up in the more intensive self-monitoring group were responsible for the difference in costs, compared to the less intensive self-monitoring group.There were few data on the effects on other outcomes and these effects were not statistically significant. None of the studies reported data on morbidity. AUTHORS' CONCLUSIONS: From this review, we conclude that when diabetes duration is over one year, the overall effect of self-monitoring of blood glucose on glycaemic control in patients with type 2 diabetes who are not using insulin is small up to six months after initiation and subsides after 12 months. Furthermore, based on a best-evidence synthesis, there is no evidence that SMBG affects patient satisfaction, general well-being or general health-related quality of life. More research is needed to explore the psychological impact of SMBG and its impact on diabetes specific quality of life and well-being, as well as the impact of SMBG on hypoglycaemia and diabetic complications.

Effects of self-monitoring of glucose in non-insulin treated patients with type 2 diabetes: design of the IN CONTROL-trial.

BACKGROUND: Diabetes specific emotional problems interfere with the demanding daily management of living with type 2 diabetes mellitus (T2DM). Possibly, offering direct feedback on diabetes management may diminish the presence of diabetes specific emotional problems and might enhance the patients' belief they are able to manage their illness. It is hypothesized that self-monitoring of glucose in combination with an algorithm how and when to act will motivate T2DM patients to become more active participants in their own care leading to a decrease in diabetes related distress and an increased self-efficacy. METHODS AND DESIGN: Six hundred patients with T2DM (45 < or = 75 years) who receive care in a structured diabetes care system, HbA1c > or = 7.0%, and not using insulin will be recruited and randomized into 3 groups; Self-monitoring of Blood Glucose (SMBG), Self-monitoring of Urine Glucose (SMUG) and usual care (n = 200 per group). Participants are eligible if they have a known disease duration of over 1 year and have used SMBG or SMUG less than 3 times in the previous year. All 3 groups will receive standardized diabetes care. The intervention groups will receive additional instructions on how to perform self-monitoring of glucose and how to interpret the results. Main outcome measures are changes in diabetes specific emotional distress and self-efficacy. Secondary outcome measures include difference in HbA1c, patient satisfaction, occurrence of hypoglycaemia, physical activity, costs of direct and indirect healthcare and changes in illness beliefs. DISCUSSION: The IN CONTROL-trial is designed to explore whether feedback from self-monitoring of glucose in T2DM patients who do not require insulin can affect diabetes specific emotional distress and increase self-efficacy. Based on the self-regulation model it is hypothesized that glucose self-monitoring feedback changes illness perceptions, guiding the patient to reduce emotional responses to experienced threats, and influences the patients ability to perform and maintain self-management skills.