Patient Reported Outcomes in a Randomized Trial of Closed-Loop Control: The Pivotal International Diabetes Closed Loop Trial.

BACKGROUND Closed-Loop Control (CLC) has been shown to improve glucose time in range and other glucose metrics; however, randomized trials longer than 3 months comparing CLC with sensor-augmented pump (SAP) therapy are limited. We recently reported glucose control outcomes from the 6-month international Diabetes Closed Loop (iDCL) trial; we now report patient-reported outcomes (PROs) in this iDCL trial. METHODS Participants were randomized 2:1 to CLC (N=112) versus SAP (N=56) and completed questionnaires including Hypoglycemia Fear Survey, Diabetes Distress Scale (DDS), Hypoglycemia Awareness, Hypoglycemia Confidence, Hyperglycemia Avoidance, and Positive Expectancies of CLC (INSPIRE) at baseline, 3, and 6 months. CLC participants also completed Diabetes Technology Expectations and Acceptance and System Usability Scales (SUS). RESULTS The Hypoglycemia Fear Survey Behavior subscale improved significantly after 6 months of CLC compared with SAP. DDS did not differ except for powerless subscale scores, which worsened at 3 months in SAP. Whereas Hypoglycemia Awareness and Hyperglycemia Avoidance did not differ between groups, CLC participants showed a tendency towards improved confidence in managing hypoglycemia. The INSPIRE questionnaire showed favorable scores in the CLC group for teens and parents, with a similar trend for adults. At baseline and six months, CLC participants had high positive expectations for the device with Diabetes Technology Acceptance and SUS showing high benefit and low burden scores. CONCLUSION CLC improved some PROs compared with SAP. Participants reported high benefit and low burden with CLC.