Effect of Continuous Glucose Monitoring on Glycemic Control in Adults With Type 1 Diabetes Using Insulin Injections

Abstract

IMPORTANCEPrevious clinical trials showing the benefit of continuous glucose monitoring (CGM) in the management of type 1 diabetes predominantly have included adults using insulin pumps, even though the majority of adults with type 1 diabetes administer insulin by injection.OBJECTIVE To determine the effectiveness of CGM in adults with type 1 diabetes treated with insulin injections.DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial conducted between October 2014 and May 2016 at 24 endocrinology practices in the United States that included 158 adults with type 1 diabetes who were using multiple daily insulin injections and had hemoglobin A 1c (HbA 1c ) levels of 7.5% to 9.9%.INTERVENTIONS Random assignment 2:1 to CGM (n = 105) or usual care (control group; n = 53).MAIN OUTCOMES AND MEASURES Primary outcome measure was the difference in change in central-laboratory-measured HbA 1c level from baseline to 24 weeks. There were 18 secondary or exploratory end points, of which 15 are reported in this article, including duration of hypoglycemia at less than 70 mg/dL, measured with CGM for 7 days at 12 and 24 weeks. RESULTS Among the 158 randomized participants (mean age, 48 years [SD, 13]; 44% women; mean baseline HbA 1c level, 8.6% [SD, 0.6%]; and median diabetes duration, 19 years [interquartile range, 10-31 years]), 155 (98%) completed the study. In the CGM group, 93% used CGM 6 d/wk or more in month 6. Mean HbA 1c reduction from baseline was 1.1% at 12 weeks and 1.0% at 24 weeks in the CGM group and 0.5% and 0.4%, respectively, in the control group (repeated-measures model P < .001). At 24 weeks, the adjusted treatment-group difference in mean change in HbA 1c level from baseline was -0.6% (95% CI, -0.8% to -0.3%; P < .001). Median duration of hypoglycemia at less than <70 mg/dL was 43 min/d (IQR, 27-69) in the CGM group vs 80 min/d (IQR, in the control group (P = .002). Severe hypoglycemia events occurred in 2 participants in each group.CONCLUSIONS AND RELEVANCE Among adults with type 1 diabetes who used multiple daily insulin injections, the use of CGM compared with usual care resulted in a greater decrease in HbA 1c level during 24 weeks. Further research is needed to assess longer-term effectiveness, as well as clinical outcomes and adverse effects.

A Simple Composite Metric for the Assessment of Glycemic Status from Continuous Glucose Monitoring Data: Implications for Clinical Practice and the Artificial Pancreas

“…Despite technical problems with early generations of the technology, numerous studies have found that sustained use of CGM technology improved overall glycemic control in both adults and children with type 1 diabetes. 2,[4][5][6] Compared with intermittent episodic capillary fingerstick blood glucose testing, continuous glucose monitoring systems produce very large amounts of data. The development of automated data visualization tools for continuous glucose monitoring systems has been a major focus of research in academia and in industry.…”

Outcome Prediction in Acute Stroke Patients by Continuous Glucose Monitoring

“…A CGM device records blood glucose levels every 5 minutes and obtains glucose parameters, and patients are accordingly able to receive intensive glucose management 14. The aim of this study was to clarify the detailed dynamics of blood glucose levels in acute stroke patients regardless of the presence of diabetes mellitus using a CGM device and to identify the parameters related to death or dependency at 3 months and early neurological deterioration within 7 days after stroke.…”

Continuous Glucose Monitoring with Multiple Daily Insulin Treatment: Outcome Studies

“…The mean HbA1c dropped in both groups to -1.0% in the CGM group and -0.4% in the SMBG group for an adjusted treatment-group difference of -0.6% (95% CI -0.8 to -0.3; P < 0.001). 42 The time spent in hypoglycemia (<70 mg/dL) was 43 min/day versus 80 min/day in the CGM versus SMBG groups, respectively, P = 0.002. 42 The GOLD trial used a crossover design with half of the 161 randomized participants using CGM for 6 months in addition to SMBG, followed by a 4-month washout period, then 6 months of usual care with SMBG alone, whereas the other half of the participants performed SMBG for the initial 6 months, and washout period followed by 6 months of CGM.…”

“…42 The time spent in hypoglycemia (<70 mg/dL) was 43 min/day versus 80 min/day in the CGM versus SMBG groups, respectively, P = 0.002. 42 The GOLD trial used a crossover design with half of the 161 randomized participants using CGM for 6 months in addition to SMBG, followed by a 4-month washout period, then 6 months of usual care with SMBG alone, whereas the other half of the participants performed SMBG for the initial 6 months, and washout period followed by 6 months of CGM. 43 Followup data were available for 142 participants, who wore the CGM between 86.5% and 91.9% of the time assigned.…”

“…Conventional Therapy for Glycemic Control in Adults with Type 1 Diabetes Treated with Multiple Daily Injections) randomized clinical trials specifically targeted MDI-treated patients to evaluate the added benefit of CGM in addition to SMBG versus SMBG alone. 42,43 Both studies used the DexCom G4 Platinum CGM system. In DIAMOND, 152 participants, mean age 48, mean baseline HbA1c 8.6%, were randomized to CGM plus SMBG or SMBG alone for 24 weeks.…”