Dexcom G6 Intervention Study

Management of Inpatient Hyperglycemia by Continuous Glucose Monitoring in Insulin-treated Patients With Diabetes: Dexcom G6 Intervention Study

The study will assess if Continuous Glucose Monitoring (CGM) represents a better tool to guide healthcare providers in adjusting insulin therapy, by providing a more complete 24-hour assessment of glucose values compared to Point of Care (POC) testing, during hospitalization and after hospital discharge in general medicine and surgery patients with Type 2 Diabetes (T2D) and Type 1 Diabetes (T1D).

Diabetes is reported in 20-34% of hospitalized adult patients in general medicine and surgery units and there is a large body of literature showing a strong association between diabetes and increased hospital mortality and morbidity. Clinical guidelines have recommended the use of basal bolus insulin regimens as the preferred management approach of non-intensive care unit (ICU) patients with diabetes, as it has been shown to be effective in improving glycemic control and reducing hospital complications. However, hypoglycemia is a common adverse event of insulin therapy, with incidence rates ranging between 12% and 35% in randomized studies in non-ICU settings. The development of hypoglycemia, like hyperglycemia, has been associated with higher rates of hospital complications, higher health care resource utilization, and hospital mortality. Bedside point-of-care (POC) capillary glucose monitoring is the standard of care to assess glycemic control in the hospital. Diabetes guidelines recommend bedside capillary POC testing before meals and at bedtime to assess glycemic control and to adjust insulin therapy in the hospital. In contrast to POC testing, continuous glucose monitoring (CGM) measures interstitial glucose every 5-15 minutes, thus providing a more complete glycemic profile during 24-hours compared to standard POC glucose testing. The study will assess if CGM represents a better tool to guide healthcare providers in adjusting insulin therapy by providing a more complete 24-hour assessment of glucose values compared to POC testing, during hospitalization and after hospital discharge in general medicine and surgery patients with T2D and T1D. Participants will be randomized to have the standard of care POC testing plus wear a sham CGM or to wear a real-time Dexcom G6 CGM, which provide BG readings every 5 minutes for up to 10 days during hospitalization. At the point of hospital discharge, participants with poorly controlled diabetes will be invited to participate in an open label outpatient study where they will wear a Dexcom G6 CGM or sham device for 10 days.

Glycemic control, Bedside point-of-care capillary glucose monitoring, Dexcom, Continuous glucose monitoring, Hyperglycemia, Inpatient

Patients will wear a real-time Dexcom G6 CGM, which provide BG readings every 5 minutes for up to 10 days. In addition, patients will undergo POC testing before meals and bedtime per hospital protocol. Insulin therapy will be titrated based on daily CGM printouts, which will include BG readings, glycemic excursions, hypoglycemia and severe hyperglycemia values throughout the day. Patients will wear a CGM in the current approved insertion site, the abdomen, and in the upper arm.

Glucose monitoring by POC testing will be performed before meals and at bedtime. Results will be uploaded in the electronic medical record (EMR) system. The research team together with the PCP team will adjust daily insulin orders based on POC readings (standard of care). In addition, patients will wear a 'blinded' CGM where no results will be visualized by patients, nursing staff, primary care physician (PCP) or research teams.

A blinded factory-calibrated continues glucose monitoring sensor system Dexcom G6 will be placed shortly after admission. Two CGM devices will be inserted in all patients - one in the abdomen and one in the arm to also assess differences in blood glucose readings between upper extremity and abdominal insertion sites. Information on CGM readings will be collected daily during the hospital stay up to 10 days using the Dexcom Studio software to download the Dexcom receiver data.

Standard of care - bedside point-of-care (POC) capillary blood glucose (BG) monitoring will be done before meals and bedtime daily during the hospital stay up to 10 days.

A random (non-fasting) blood glucose measurement of 140 mg/dL or less is considered normal, while a measurement of 200 mg/dL or more indicates diabetes.

The mean number of clinically significant hypoglycemia events, defined as BG <54 mg/dl (3.0mmol/L), per participant is presented here.

The mean number of hypoglycemia events, defined as BG < 70 (<3.9 mmol/L), per participant during hospitalization is presented here.

The mean number of events of nocturnal hypoglycemia per participant are presented here. Nocturnal hypoglycemia occurs between the hours of 12:00 midnight and 6:00 ante meridiem (AM). Hypoglycemia is defined as BG < 70 mg/dL (<3.9 mmol/L) and severe hypoglycemia is defined as BG < 54 mg/dL (<3.0 mmol/L).

The percentage of time spent with BG below the desired range, during the day and night of hospitalization was assessed. Hypoglycemia is defined as BG < 70 mg/dL (<3.9 mmol/L) and severe hypoglycemia is defined as BG < 54 mg/dL (<3.0 mmol/L).

The percentage of time above the desired BG range, during the day and night while hospitalized was assessed.

Mean amplitude of glycemic excursions (MAGE), together with mean and standard deviation, is the parameter for assessing glycemic variability and is calculated based on the arithmetic mean of differences between consecutive peaks and nadirs of differences greater than one standard deviation of mean glycemia. It is designed to assess major glucose swings and exclude minor ones.

The mean absolute relative difference (MARD) reflects accuracy of the CGM glucose reading compared to the reference POC reading. This is the current standard for assessing accuracy of glucometer readings. Lower MARD indicates smaller differences between the CGM and meter value; a higher MARD value indicates larger differences. A three way and direct head-to-head comparison of data from the abdomen, upper arm and POC BG will be compared.

Events related to sensor changes (blinded sensor for the POC group or real-time sensor for CGM group), such as removal for procedures or imaging, sensors failures, and sensors dislodgments were recorded.

A random (non-fasting) blood glucose measurement of 140 mg/dL or less is considered normal, while a measurement of 200 mg/dL or more indicates diabetes.

Glycemic control after hospital discharge is measured by the percent of time with BG in the range of 70-180 mg/dL.

The mean number of clinically significant hypoglycemia events, defined as BG <54 mg/dl (3.0mmol/L), during the day and night after hospital discharge, per participant is presented here.

The mean number of hypoglycemia events, defined as BG < 70 (<3.9 mmol/L), per participant after hospital discharge is presented here.

Hypoglycemia is defined as BG < 70 mg/dL (<3.9 mmol/L) and severe hypoglycemia is defined as BG < 54 mg/dL (<3.0 mmol/L).

The percentage of time above the desired BG range, during the day and night after hospital discharge was assessed.

Mean amplitude of glycemic excursions (MAGE), together with mean and standard deviation, is the parameter for assessing glycemic variability and is calculated based on the arithmetic mean of differences between consecutive peaks and nadirs of differences greater than one standard of mean glycemia. It is designed to assess major glucose swings and exclude minor ones

Inclusion Criteria: Males and females ≥ 18 years admitted to a general medicine or surgical services. History of T1D or T2D receiving insulin therapy during hospital admission. Subjects must have a randomization BG <400 mg/dL without laboratory evidence of diabetic ketoacidosis (bicarbonate < 18 milliequivalents per litre (mEq/L), potential of hydrogen (pH) < 7.30, or positive serum or urinary ketones). Patients with expected hospital length-of-stay of 2 or more day Exclusion Criteria: Patients with acute illness admitted to the ICU or expected to require admission to the ICU. Patients expected to require MRI procedures during hospitalization. Patients with clinically relevant hepatic disease (diagnosed liver cirrhosis and portal hypertension), corticosteroid therapy, end-stage renal disease (dialysis), or anasarca (massive peripheral edema). Mental condition rendering the subject unable to understand the nature, scope, and possible consequences of the study. Female subjects who are pregnant or breast-feeding at time of enrollment into the study. Coronavirus Disease 2019 (COVID-19) infection

Individual participant data that underlie the results reported in publications for this study (including text, tables, figures, and appendices) will be available for sharing after de-identification.

Data will be available for sharing beginning 6 months after publication and ending 5 years after publication.

Individual participant data will be made available for sharing with researchers who provide a methodologically sound proposals should email proposals to geumpie@emory.edu. To gain access, data requestors will need to sign a data access agreement.

Spanakis EK, Urrutia A, Galindo RJ, Vellanki P, Migdal AL, Davis G, Fayfman M, Idrees T, Pasquel FJ, Coronado WZ, Albury B, Moreno E, Singh LG, Marcano I, Lizama S, Gothong C, Munir K, Chesney C, Maguire R, Scott WH, Perez-Guzman MC, Cardona S, Peng L, Umpierrez GE. Continuous Glucose Monitoring-Guided Insulin Administration in Hospitalized Patients With Diabetes: A Randomized Clinical Trial. Diabetes Care. 2022 Oct 1;45(10):2369-2375. doi: 10.2337/dc22-0716.

Spanakis EK, Singh LG, Siddiqui T, Sorkin JD, Notas G, Magee MF, Fink JC, Zhan M, Umpierrez GE. Association of glucose variability at the last day of hospitalization with 30-day readmission in adults with diabetes. BMJ Open Diabetes Res Care. 2020 May;8(1):e000990. doi: 10.1136/bmjdrc-2019-000990.