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Published on: June 11, 2012
Effects of hybrid closed-loop system on glycemic control and psychological aspects in persons with type 1 diabetes
Tomoaki Akiyama1, Tadashi Yamakawa1,2, Kazuki Orime1
1Department of Endocrinology and Diabetes, Yokohama City University Medical Center, Yokohama, Japan.
Aims/Introduction:
This study evaluated the effects of the Medtronic MiniMed 770G hybrid closed-loop system on glycemic control and psychological aspects in persons with type 1 diabetes mellitus.
Materials And Methods:
This 3-month prospective observational study included 22 participants with type 1 diabetes mellitus who used the Medtronic MiniMed 640G predictive low-glucose suspend system and were switched to the 770G system. Time in the range of 70-180 mg/dL and glycated hemoglobin levels were evaluated; satisfaction, emotional distress and quality of life were assessed using self-reported questionnaires, including the Diabetes Treatment Satisfaction Questionnaire Status, Problem Area in Diabetes and Diabetes Therapy-Related Quality of Life.
Results:
Time in the range of 70-180 mg/dL increased (63.5 ± 13.4 to 73.0 ± 10.9% [mean ± standard deviation], P = 0.0010), and time above the range of 181-250 mg/dL decreased (26.9 ± 8.9 to 19.6 ± 7.1%, P < 0.0005). Glycated hemoglobin levels decreased (7.7 ± 1.0 to 7.2 ± 0.8%, P = 0.0021). The percentage of participants with time below the range of 54-69 mg/dL <4% of readings increased from 91% to 100% (P < 0.0005). No significant changes were detected in the satisfaction, emotional distress and quality of life levels, but increased sensor calibration might be related to worsened emotional distress and quality of life.
Conclusions:
The hybrid closed-loop system decreased hyperglycemia and minimized hypoglycemia, but did not improve psychological aspects compared with the predictive low-glucose suspend system, probably because sensor calibration was increased.
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