Self-monitoring of Blood Glucose in Insulin-treated Patients With Type 2 Diabetes

Self-monitoring of Blood Glucose in Insulin-treated Patients With Type 2 Diabetes: a 9-month Randomised Controlled Trial

Primary Objective: The objective of the study is to investigate the effect of a specific frequency of Self-monitoring of blood glucose (SMBG) on glycemic control and quality of life in patients with type 2 diabetes and who are in stable good glycemic control and using 1 insulin injection daily. The research question is: Does a less intensive frequency of SMBG in insulin-treated patients with type 2 diabetes, who are in stable good glycemic control, using 1 insulin injection daily, lead to a clinically relevant increase of HbA1c (an increase of 0.5%) and what is the effect on quality of life? Secondary objectives: The secondary objectives is to investigate the effect of a specific frequency of SMBG on the number of hypo and hyper glycaemia, number of extra diabetes-related contacts with the health care provider, and the diabetes medication.

SUMMARY Rationale: Self-monitoring of blood glucose (SMBG) is an important tool in diabetes care to achieve and maintain good glycemic control. But how often 'should' the patient measure the capillary glucose concentration? There is no general agreement between professionals, and there is no evidence for a specific frequency and timing. Objective: The objective of the study is to investigate the effect of a specific frequency of SMBG on glycemic control and quality of life in patients with type 2 diabetes and who are in stable good glycemic control and using 1 insulin injection daily. Study design: An open Randomised Controlled Trial. Study population: Patients with insulin-treated diabetes type 2, > 18 years of age, using 1 insulin injection daily, performing SMBG > 1 year, HbA1c ≤ 58 mmol/mol (< 7.5%) in the preceding 12 months, sufficient knowledge of the Dutch language, no hypo-unawareness, no serious co-morbidity Intervention: Patients are instructed to measure their blood glucose concentrations 4 times per day (pre-prandial and before bedtime) one day weekly in group A, one day per two weeks in group B and one day monthly in group C. Patients are asked to keep a diary with the readings and the probably extra measurements, including the reasons. Main study parameters/endpoints: The main study parameters are glycemic control and quality of life. A difference of > 0.5% (> 5.5 mmol/mol) in HbA1c is considered to be relevant. Quality of life is measured with 3 validated questionnaires. Nature and extent of the burden and risks associated with participation, benefit and group relatedness: Patients in this study are used to perform SMBG. During the study, they are asked to monitor their glucose concentrations in a controlled, specific frequency (different kind of usual care are compared). And they are asked to fill in 3 questionnaires in the beginning and at the end of the study. Extra HbA1c measurements can be necessary. No side effects are expected, but safety is incorporated through HbA1c measurements every 3 months and every 3 months the diary will be discussed in the scheduled visits. Furthermore, extra measurements are allowed when necessary.

Patients are instructed to measure their blood glucose concentrations 4 times per day (pre-prandial and before bedtime) one day weekly in group A.

Patients are instructed to measure their blood glucose concentrations 4 times per day (pre-prandial and before bedtime) one day per two weeks in group B.

Patients are instructed to measure their blood glucose concentrations 4 times per day (pre-prandial and before bedtime) Group C: one day monthly

Patients are instructed to measure their blood glucose concentrations 4 times per day (pre-prandial and before bedtime: high frequency: one day weekly middle frequency:one day per two weeks low frequency:one day monthly

The main study parameter is glycemic control. Glycemic control is measured by HbA1c. A difference of 0.5% (> 5.5 mmol/mol) in HbA1c between groups is considered to be relevant.

The secondary study parameter is quality of life. The quality of life is measured by 3 validated questionnaires: the 12-item Short Form Health Survey, the 20-item Problems Areas in Diabetes Scale (PAID) and the 13-item Summary of Diabetes Self care Activities. Furthermore, the glucose concentrations measured by SMBG should be between 4-7 mmol/l, preprandial and between 8-10 mmol/l before bed time. The endpoint is the number of glucose concentrations who are out of range at every 4th week.The number of hypo and hyperglycaemia are reported in the diary.

Inclusion Criteria: Patients with insulin-treated diabetes type 2 > 18 years of age using 1 insulin injection daily, performing SMBG > 1 year HbA1c ≤ 58 mmol/mol (< 7.5%) in the preceding 12 months sufficient knowledge of the Dutch language.- Exclusion Criteria: no hypo-unawareness no serious co-morbidity (as judged by their own GP) patients who measure their blood glucose concentration (4 measurements a day) more than once a week on average

Hortensius J, Kleefstra N, Landman GWD, Houweling BT, Groenier KH, van der Bijl JJ, Bilo H. Effects of three frequencies of self-monitored blood glucose on HbA1c and quality of life in patients with type 2 diabetes with once daily insulin and stable control: a randomized trial. BMC Res Notes. 2018 Jan 15;11(1):26. doi: 10.1186/s13104-018-3138-7.