title: Effect of Continuous Glucose Monitoring on Glycemic Control in Adults With Type 1 Diabetes Using Insulin Injections: The DIAMOND Randomized Clinical Trial.
abstract: Previous 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.
  
  
  
  To determine the effectiveness of CGM in adults with type 1 diabetes treated with insulin injections.
  
  
  
  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 A1c (HbA1c) levels of 7.5% to 9.9%.
  
  
  
  Random assignment 2:1 to CGM (n = 105) or usual care (control group; n = 53).
  
  
  
  Primary outcome measure was the difference in change in central-laboratory-measured HbA1c 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.
  
  
  
  Among the 158 randomized participants (mean age, 48 years [SD, 13]; 44% women; mean baseline HbA1c 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 HbA1c 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 HbA1c 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, 36-111) in the control group (P = .002). Severe hypoglycemia events occurred in 2 participants in each group.
  
  
  
  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 HbA1c level during 24 weeks. Further research is needed to assess longer-term effectiveness, as well as clinical outcomes and adverse effects.
  
  
  
  clinicaltrials.gov Identifier: NCT02282397.
authors.affiliation: Jaeb Center for Health Research, Tampa, Florida.
authors.forename: Roy W
authors.initials: RW
authors.lastname: Beck
authors.affiliation: Jaeb Center for Health Research, Tampa, Florida.
authors.forename: Tonya
authors.initials: T
authors.lastname: Riddlesworth
authors.affiliation: Jaeb Center for Health Research, Tampa, Florida.
authors.forename: Katrina
authors.initials: K
authors.lastname: Ruedy
authors.affiliation: Oregon Health & Science University, Portland.
authors.forename: Andrew
authors.initials: A
authors.lastname: Ahmann
authors.affiliation: Park Nicollet Institute, International Diabetes Center, St Louis Park, Minnesota.
authors.forename: Richard
authors.initials: R
authors.lastname: Bergenstal
authors.affiliation: Diabetes & Glandular Disease Clinic, San Antonio, Texas.
authors.forename: Stacie
authors.initials: S
authors.lastname: Haller
authors.affiliation: Jaeb Center for Health Research, Tampa, Florida.
authors.forename: Craig
authors.initials: C
authors.lastname: Kollman
authors.affiliation: Division of Endocrinology, Henry Ford Medical Center, Detroit, Michigan.
authors.forename: Davida
authors.initials: D
authors.lastname: Kruger
authors.affiliation: Washington University in St Louis, St Louis, Missouri.
authors.forename: Janet B
authors.initials: JB
authors.lastname: McGill
authors.affiliation: Behavioral Diabetes Institute, San Diego, California.
authors.forename: William
authors.initials: W
authors.lastname: Polonsky
authors.affiliation: Joslin Diabetes Center, Boston, Massachusetts.
authors.forename: Elena
authors.initials: E
authors.lastname: Toschi
authors.affiliation: Joslin Diabetes Center, Boston, Massachusetts.
authors.forename: Howard
authors.initials: H
authors.lastname: Wolpert
authors.affiliation: Dexcom Inc, San Diego, California.
authors.forename: David
authors.initials: D
authors.lastname: Price
mesh_terms: D000328:Adult; D000368:Aged; D001786:Blood Glucose / Q000032:analysis*; D015190:Blood Glucose Self-Monitoring / Q000295:instrumentation* / Q000523:psychology / Q000706:statistics & numerical data; D003922:Diabetes Mellitus, Type 1 / Q000097:blood* / Q000188:drug therapy*; D004334:Drug Administration Schedule; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D006943:Hyperglycemia / Q000097:blood / Q000188:drug therapy; D007003:Hypoglycemia / Q000097:blood / Q000139:chemically induced; D007004:Hypoglycemic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D007328:Insulin / Q000008:administration & dosage* / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D017060:Patient Satisfaction; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D006442:Glycated Hemoglobin; D007004:Hypoglycemic Agents; D007328:Insulin