This study is designed to explore the effect of feedback counseling using professional continuous glucose monitoring on glycemic control, self-efficacy, and self-management behaviors among middle aged and older adults with poor controlled type 2 diabetes mellitus. This study also explores the difference on timing of feedback after continuous glucose monitoring exam.

After scheduled routine professional continuous glucose monitoring (CGM) exam, participants in both the intervention and control group receive ordinary education and regimen adjustment as indicated based on CGM results. For participants in the intervention group, they will also receive CGM counseling immediately on the day of CGM sensor removal. For participants in the control group, they will receive CGM counseling on the day of routine 3 months outpatient visit.

Qualitative data are collected through in-depth interview: User expectation, acceptability and satisfaction of CGM are also explored during in-depth interview with a semi-structured questionnaire.

Quantitative data were collected through validated questionnaires, including evaluation of depression by a short form of the Center for Epidemiologic Studies Depression Scale Revised (CES-D-R), emotional stress by Problem Areas in Diabetes Scale (PAID), self efficacy by Stanford Self-Efficacy for Diabetes (SES), at pretest and 3 months after CGM counseling.

Anthropometric Measurements. Body height, body weight, body mass index, and blood pressure were recorded at pre-test and post-test interview.

Blood Tests. Routine biochemistry, fasting plasma glucose, hemoglobin A1c (HbA1c) are collected within 2 weeks of pretest and posttest day.

Inclusion Criteria:

• Age 45 years old or more at recent outpatient visits;
• Type 2 diabetic patients followed up at National Cheng Kung University Hospital;
• Patients planned to receive CGM suggested by primary care physician due to inadequate controlled blood glucose.

Exclusion Criteria:

• Patients with diagnosis of generalized inflammation, advanced malignancy, end-stage renal disease on regular dialysis, status post renal transplantation, end-stage liver, heart or pulmonary disease;
• Patients who are taking systemic glucocorticoids;
• Any acute or chronic inflammatory disease as determined by a leukocyte count over 10,000/mm3 or clinical signs of infection;
• Patients who could not complete the questionnaires or who could not follow order due to cognitive impairment or in bed-ridden status;
• Patients diagnosed as thalassemia, glucose-6-phosphate dehydrogenase deficiency, and any other hemoglobinopathies that may influence the accuracy of hemoglobulin A1c measurement were also excluded. Patients who received blood transfusion in recent 3 months were also excluded.

The study protocol will be shared after study publication.