Type 1 Diabetes Mellitus
Conditions
Brief summary
A multi-center, randomized, crossover trial consisting of three sequential 12-week periods, with the HCL feature used during one period, the PLGS feature used during one period and SAP therapy (control) during one period. The crossover trial will be preceded by a run-in phase in which participants will receive training using the study devices (Dexcom G6 and Tandem t:slim X2 pump). After the last crossover period, participants will be given the opportunity to use study devices for an additional 12 weeks to assess preference of system use (PLGS, HCL or SAP) and associated characteristics, durability and safety in a more real-world setting with less frequent study contact.
Detailed description
Automated insulin delivery (AID) technologies hold the promise of optimizing glycemic control and reducing the burden of diabetes care for patients with Type 1 Diabetes (T1D). However, clinical trials of lower burden AID technologies have not included older adults in sufficient numbers to allow for focused evaluation of efficacy and quality of life (QOL) impacts that may differ from those observed in younger age groups. Most notably, primary endpoints have focused on reducing hyperglycemia, while avoidance of hypoglycemia is of upmost concern for older adults with T1D. T1D Exchange clinic registry data have shown severe hypoglycemia (SH) occurs more commonly in older adults with longstanding T1D than in younger individuals with events occurring just as often with HbA1c levels \>8.0% as with HbA1c levels \<7.0%. These data do not support the strategy of raising the HbA1c as being an effective approach for hypoglycemia prevention in older adults with T1D. In addition to acutely altered mental status, hypoglycemia is associated with an increased risk for falls leading to fractures, car accidents, emergency room (ER) visits, hospitalizations, and mortality resulting in substantial societal costs. The occurrence of hypoglycemia, hypoglycemia unawareness and fear of hypoglycemia have adverse effects on overall QOL of both individuals with T1D and their families. While continuous glucose monitoring (CGM) technology alone has the potential to be beneficial in reducing hypoglycemia in older patients, our preliminary data from the Wireless Innovations for Seniors with Diabetes Mellitus (WISDM) trial shows a majority of patients still have frequent hypoglycemia even when using CGM. Thus, knowledge of CGM alone may not be sufficient to avoid hypoglycemia in this population. Predictive low-glucose suspend algorithms have particular promise when the primary goal is hypoglycemia avoidance rather than glucose reduction. Whether the added complexity of closed loop systems provides additional glycemic benefit is not known. There is a critical need to determine whether automated insulin delivery can reduce hypoglycemia in the older adult population with T1D.
Interventions
DEVICETandem t:slim X2 with HCL or PLGS
The system components include the t:slim X2 with Control-IQ Technology and the Dexcom CGM G6. The modular control algorithm has a safety supervision module that limits insulin delivery to prevent hypoglycemia at all times. The algorithm gradually decreases hyperglycemia from bedtime to reach a target of 120 mg/dL by waking time. During awake hours, the control algorithm attempts to maintain glucose within a target range (112.5 to 160 mg/dL) with meal time insulin boluses delivered based on usual bolus procedures undertaken by patients on an insulin pump (Hybrid closed loop). The system components include the t:slim X2 with with Basal-IQ Technology and the Dexcom CGM G6. The PLGS System is able to stop and resume basal insulin delivery automatically in response to predicted or low sensor glucose values, thereby reducing the incidence and duration of hypoglycemic episodes. The pump includes the hypoglycemia minimization strategy that will issue insulin delivery commands.
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
DexCom, Inc.
Tandem Diabetes Care, Inc.
University of Minnesota - Advanced Research and Diagnostic Laboratory
Mayo Clinic
University of Pennsylvania
AdventHealth Diabetes Institute
Washington State University
Jaeb Center for Health Research
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
Randomized crossover trial with three 12-week crossover periods (HCL during one period, PLGS during one period, and SAP therapy (control) during one period) preceded by a run-in phase.
Eligibility
Sex/Gender
ALL
Age
65 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
1. Clinical diagnosis of type 1 diabetes 2. Age ≥ 65 years old 3. T1D Duration of at least 1 year 4. HbA1c \< 10.0% from point of care or local lab within the past 6 months 5. Insulin regimen involves basal/bolus insulin via insulin pump or multiple daily injections 6. Most recent GFR ≥ 30 ml/min/m\^2 from local lab within the past 6 months 7. Willingness to use a rapid acting insulin compatible with the Tandem t:slim X2 pump (currently aspart and lispro; other rapid acting insulins likely to be approved for pump use prior to study initiation such as Fiasp) 8. Familiarity with and willingness to use a carbohydrate ratio for meal boluses 9. Willing to use study devices and automated insulin delivery features 10. Ability to download study devices at home or if not able to download at home willing to come into clinic to bring devices for download of data at visits and as needed for safety 11. Participant is independently managing his/her diabetes with respect to insulin administration and glucose monitoring (may include assistance from spouse or other caregiver) 12. Participant understands the study protocol, agrees to comply with it and is able to successfully pass the consent understanding assessment with no more than 2 attempts 13. Participant comprehends written and spoken English 14. At least 240 hours of CGM readings available during the end of run-in assessment 15. At least 1.5% of time with CGM glucose levels \< 70 mg/dL prior to SAP initiation 16. Active prescription for glucagon and willing and able to have glucagon available
Exclusion criteria
1. Use of PLGS technology or HCL insulin delivery in the past 1 month 2. History of 1 or more Diabetic Ketoacidosis episodes in the previous 6 months 3. Clinical diagnosis by a primary care provider, neurologist or psychiatrist of dementia, in the investigator's opinion a suspected severe cognitive impairment such that it would preclude ability to understand the study or use devices, or a score of 6 or less out of 15 on the 5 min MoCA (5-min T MoCA Version 2.1) (mild cognitive impairment is not an exclusion) 4. A condition, which in the opinion of the investigator or designee, would put the participant or study at risk, including severe vision or hearing impairment and any contraindication to the use of any of the study devices per FDA labeling 5. Known adhesive allergy or skin reaction during the run-in pre-randomization phase or previous difficulty with pump and CGM insertions that would preclude participation in the randomized trial 6. Concurrent use of any non-insulin glucose-lowering agent other than metformin (including GLP-1 agonists, Symlin, DPP-4 inhibitors, SGLT-2 inhibitors, sulfonylureas) 7. Stage 4 or 5 renal disease 8. The presence of a significant medical or psychiatric condition or use of a medication that in the judgment of the investigator may affect completion of any aspect of the protocol, or is likely to be associated with life expectancy of \<1 year
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| CGM Measured Time <70 mg/dL | weeks 5-12 of 12 weeks for each intervention of the crossover | Primary Outcome: Percentage of sensor glucose values \<70 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics. Since the hypoglycemia endpoints had skewed distributions, values were winsorized at the 10th and 90th percentiles. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Glucose Control | weeks 5-12 of 12 weeks for each arm of the crossover | Mean glucose (mg/dL) |
| Glucose Control - Coefficient of Variation | weeks 5-12 of 12 weeks for each arm of the crossover | Coefficient of variation (%) |
| % Time > 180 mg/dL | weeks 5-12 of 12 weeks for each intervention of the crossover | Percentage of values \>180 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics. |
| % Time > 250 mg/dL | weeks 5-12 of 12 weeks for each intervention of the crossover | Percentage of values \>250 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics. |
| HbA1c | at 12 week visit for each arm of the crossover | HbA1c % |
| Hypoglycemia Unawareness - Gold Survey | at 12 week visit for each arm of the crossover | The Gold score asks subjects to indicate their awareness of hypoglycemia with '1' being always aware and '7' being never aware. Score scale 1-7; A higher score indicates more unawareness. |
| CGM Measured Time <54 mg/dL | weeks 5-12 of 12 weeks for each intervention of the crossover | Percentage of sensor glucose values \<54 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics. Since the hypoglycemia endpoints had skewed distributions, values were winsorized at the 10th and 90th percentiles. |
| Hypoglycemia | weeks 5-12 of 12 weeks for each arm of the crossover | Rate of CGM-measured hypoglycemic events per week. A hypoglycemic event is defined as 15 consecutive minutes with a sensor glucose value \<54 mg/dl. At least 2 sensor values \<54 mg/dl that are 15 or more minutes apart plus no intervening values \>54 mg/dl are required to define an event. The end of the hypoglycemic event is defined as a minimum of 15 consecutive minutes with a sensor glucose concentration \>70 mg/dl. At least 2 sensor values \>70 mg/dl that are 15 or more minutes apart with no intervening values \<70 mg/dl, are required to define the end of an event. When a hypoglycemic event ends, the study participant becomes eligible for a new event. |
| % Time 70-180 mg/dL | weeks 5-12 of 12 weeks for each intervention of the crossover | Percentage of sensor glucose values 70 to 180 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Patient Reported Questionnaires - Diabetes Distress Scale | at 12 week visit for each arm of the crossover | 28-item questionnaire used to measure diabetes-related concerns about powerlessness, management, hypoglycemia, social perceptions, eating, physician, and friends/family. Score scale 1-6; A higher score indicates more distress. |
| Patient Reported Questionnaires - AIDE Technology Acceptance | at 12 week visit for each arm of the crossover | This diabetes technology specific questionnaire based on the Technology Acceptance Model, assesses perceived system usefulness, ease of use and trust in the system. Score scale 1-5; A higher score indicates a more positive appraisal of the system. |
| Patient Reported Questionnaires - System Usability | at 12 week visit for each arm of the crossover | A 10-item questionnaire that measures overall perceived usability of a system and is technology-agnostic. Score scale 0-100; Higher score indicates better usability |
| Patient Reported Questionnaires - Hypoglycemia Fear Survey | at 12 week visit for each arm of the crossover | The Hypoglycemia Fear Survey measures several dimensions of fear of hypoglycemia among adults with type 1 diabetes. It consists of a 15-item Behavior subscale that measures behaviors involved in avoidance and over-treatment of hypoglycemia and a 18-item Worry subscale that measures anxiety and fear surrounding hypoglycemia. Scores will be calculated overall and for the worry subscale. Score scale 0-4; A higher score indicates more fear. |
| Patient Reported Questionnaires - Hypoglycemia Confidence | at 12 week visit for each arm of the crossover | The HCS is a 9-item scale that examines the degree to which people with diabetes feel able, secure, and comfortable regarding their ability to stay safe from hypoglycemic-related problems. Score scale 1-4.; A higher score indicates more confidence. |
Countries
United States
Participant flow
Pre-assignment details
This was a crossover study, so the same 82 randomized patients participated in each arm. If they drop out, they might not be in one of the arms.
Participants by arm
| Arm | Count |
|---|---|
| All Study Participants All participants were randomized to receive all interventions: Hybrid Closed Loop Control (HCL), Predictive Low-Glucose Insulin Suspension (PLGS), and Sensor-Augmented Pump (SAP). | 82 |
| Total | 82 |
Withdrawals & dropouts
| Period | Reason | FG000 |
|---|---|---|
| HCL (12 Weeks) | Withdrawal by Subject | 1 |
| PLGS (12 Weeks) | Death | 1 |
| Run-In Phase | Death | 1 |
| Run-In Phase | Not meeting screening eligibility | 9 |
| Run-In Phase | Physician Decision | 3 |
| Run-In Phase | Withdrawal by Subject | 11 |
| SAP (12 Weeks) | Death | 1 |
Baseline characteristics
| Characteristic | All Study Participants |
|---|---|
| Age, Customized 65-<70 years | 38 Participants |
| Age, Customized 70-<75 years | 33 Participants |
| Age, Customized 75-<80 years | 9 Participants |
| Age, Customized ≥80 years | 2 Participants |
| Central Lab Baseline HbA1c (%) | 7.2 percentage of glycated hemoglobin STANDARD_DEVIATION 0.9 |
| Ethnicity (NIH/OMB) Hispanic or Latino | 0 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 82 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) American Indian or Alaska Native | 1 Participants |
| Race (NIH/OMB) Asian | 0 Participants |
| Race (NIH/OMB) Black or African American | 1 Participants |
| Race (NIH/OMB) More than one race | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants |
| Race (NIH/OMB) White | 80 Participants |
| Region of Enrollment United States | 82 participants |
| Sex: Female, Male Female | 37 Participants |
| Sex: Female, Male Male | 45 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk | EG003 affected / at risk |
|---|---|---|---|---|
| deaths Total, all-cause mortality | 1 / 105 | 0 / 81 | 1 / 80 | 1 / 79 |
| other Total, other adverse events | 7 / 105 | 4 / 81 | 16 / 79 | 10 / 78 |
| serious Total, serious adverse events | 2 / 105 | 8 / 81 | 3 / 79 | 3 / 78 |
Outcome results
Primary
CGM Measured Time <70 mg/dL
Primary Outcome: Percentage of sensor glucose values \<70 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics. Since the hypoglycemia endpoints had skewed distributions, values were winsorized at the 10th and 90th percentiles.
Time frame: weeks 5-12 of 12 weeks for each intervention of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | CGM Measured Time <70 mg/dL | 1.58 % time <70 mg/dL | Standard Deviation 0.95 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | CGM Measured Time <70 mg/dL | 1.67 % time <70 mg/dL | Standard Deviation 0.96 |
| Sensor-Augmented Pump (SAP) | CGM Measured Time <70 mg/dL | 2.57 % time <70 mg/dL | Standard Deviation 1.54 |
Secondary
CGM Measured Time <54 mg/dL
Percentage of sensor glucose values \<54 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics. Since the hypoglycemia endpoints had skewed distributions, values were winsorized at the 10th and 90th percentiles.
Time frame: weeks 5-12 of 12 weeks for each intervention of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | CGM Measured Time <54 mg/dL | 0.29 % time <54 mg/dL | Standard Deviation 0.23 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | CGM Measured Time <54 mg/dL | 0.27 % time <54 mg/dL | Standard Deviation 0.2 |
| Sensor-Augmented Pump (SAP) | CGM Measured Time <54 mg/dL | 0.48 % time <54 mg/dL | Standard Deviation 0.4 |
Secondary
Glucose Control
Mean glucose (mg/dL)
Time frame: weeks 5-12 of 12 weeks for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Glucose Control | 152 mg/dL | Standard Deviation 16 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Glucose Control | 161 mg/dL | Standard Deviation 23 |
| Sensor-Augmented Pump (SAP) | Glucose Control | 160 mg/dL | Standard Deviation 20 |
Secondary
Glucose Control - Coefficient of Variation
Coefficient of variation (%)
Time frame: weeks 5-12 of 12 weeks for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Glucose Control - Coefficient of Variation | 33 % coefficient of variation | Standard Deviation 5 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Glucose Control - Coefficient of Variation | 35 % coefficient of variation | Standard Deviation 4 |
| Sensor-Augmented Pump (SAP) | Glucose Control - Coefficient of Variation | 36 % coefficient of variation | Standard Deviation 5 |
Secondary
HbA1c
HbA1c %
Time frame: at 12 week visit for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | HbA1c | 6.9 % of HbA1c | Standard Deviation 0.7 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | HbA1c | 7.1 % of HbA1c | Standard Deviation 0.8 |
| Sensor-Augmented Pump (SAP) | HbA1c | 7.0 % of HbA1c | Standard Deviation 0.8 |
Secondary
Hypoglycemia
Rate of CGM-measured hypoglycemic events per week. A hypoglycemic event is defined as 15 consecutive minutes with a sensor glucose value \<54 mg/dl. At least 2 sensor values \<54 mg/dl that are 15 or more minutes apart plus no intervening values \>54 mg/dl are required to define an event. The end of the hypoglycemic event is defined as a minimum of 15 consecutive minutes with a sensor glucose concentration \>70 mg/dl. At least 2 sensor values \>70 mg/dl that are 15 or more minutes apart with no intervening values \<70 mg/dl, are required to define the end of an event. When a hypoglycemic event ends, the study participant becomes eligible for a new event.
Time frame: weeks 5-12 of 12 weeks for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Hypoglycemia | 0.6 hypoglycemic events per week | Standard Deviation 0.5 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Hypoglycemia | 0.5 hypoglycemic events per week | Standard Deviation 0.5 |
| Sensor-Augmented Pump (SAP) | Hypoglycemia | 0.9 hypoglycemic events per week | Standard Deviation 0.8 |
Secondary
Hypoglycemia Unawareness - Gold Survey
The Gold score asks subjects to indicate their awareness of hypoglycemia with '1' being always aware and '7' being never aware. Score scale 1-7; A higher score indicates more unawareness.
Time frame: at 12 week visit for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Hypoglycemia Unawareness - Gold Survey | 2.6 score on a scale | Standard Deviation 1.6 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Hypoglycemia Unawareness - Gold Survey | 2.7 score on a scale | Standard Deviation 1.5 |
| Sensor-Augmented Pump (SAP) | Hypoglycemia Unawareness - Gold Survey | 2.9 score on a scale | Standard Deviation 1.9 |
Secondary
% Time > 180 mg/dL
Percentage of values \>180 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics.
Time frame: weeks 5-12 of 12 weeks for each intervention of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | % Time > 180 mg/dL | 24 % of time >180 mg/dL | Standard Deviation 10 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | % Time > 180 mg/dL | 31 % of time >180 mg/dL | Standard Deviation 14 |
| Sensor-Augmented Pump (SAP) | % Time > 180 mg/dL | 31 % of time >180 mg/dL | Standard Deviation 13 |
Secondary
% Time > 250 mg/dL
Percentage of values \>250 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics.
Time frame: weeks 5-12 of 12 weeks for each intervention of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | % Time > 250 mg/dL | 5.6 % of time >250 mg/dL | Standard Deviation 5.2 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | % Time > 250 mg/dL | 8.7 % of time >250 mg/dL | Standard Deviation 8.8 |
| Sensor-Augmented Pump (SAP) | % Time > 250 mg/dL | 8.6 % of time >250 mg/dL | Standard Deviation 7 |
Secondary
% Time 70-180 mg/dL
Percentage of sensor glucose values 70 to 180 mg/dL. The first 4 weeks of CGM data in each period were excluded to reduce the chance of a carryover effect. A minimum of 168 hours of data was required to calculate CGM metrics.
Time frame: weeks 5-12 of 12 weeks for each intervention of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | % Time 70-180 mg/dL | 74 % time in range 70-180 mg/dL | Standard Deviation 10 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | % Time 70-180 mg/dL | 67 % time in range 70-180 mg/dL | Standard Deviation 14 |
| Sensor-Augmented Pump (SAP) | % Time 70-180 mg/dL | 66 % time in range 70-180 mg/dL | Standard Deviation 12 |
Other Pre-specified
Patient Reported Questionnaires - AIDE Technology Acceptance
This diabetes technology specific questionnaire based on the Technology Acceptance Model, assesses perceived system usefulness, ease of use and trust in the system. Score scale 1-5; A higher score indicates a more positive appraisal of the system.
Time frame: at 12 week visit for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Patient Reported Questionnaires - AIDE Technology Acceptance | 4.1 score on a scale | Standard Deviation 0.6 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Patient Reported Questionnaires - AIDE Technology Acceptance | 4.0 score on a scale | Standard Deviation 0.7 |
| Sensor-Augmented Pump (SAP) | Patient Reported Questionnaires - AIDE Technology Acceptance | 3.9 score on a scale | Standard Deviation 0.8 |
Other Pre-specified
Patient Reported Questionnaires - Diabetes Distress Scale
28-item questionnaire used to measure diabetes-related concerns about powerlessness, management, hypoglycemia, social perceptions, eating, physician, and friends/family. Score scale 1-6; A higher score indicates more distress.
Time frame: at 12 week visit for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Patient Reported Questionnaires - Diabetes Distress Scale | 1.6 score on a scale | Standard Deviation 0.5 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Patient Reported Questionnaires - Diabetes Distress Scale | 1.7 score on a scale | Standard Deviation 0.5 |
| Sensor-Augmented Pump (SAP) | Patient Reported Questionnaires - Diabetes Distress Scale | 1.6 score on a scale | Standard Deviation 0.6 |
Other Pre-specified
Patient Reported Questionnaires - Hypoglycemia Confidence
The HCS is a 9-item scale that examines the degree to which people with diabetes feel able, secure, and comfortable regarding their ability to stay safe from hypoglycemic-related problems. Score scale 1-4.; A higher score indicates more confidence.
Time frame: at 12 week visit for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Patient Reported Questionnaires - Hypoglycemia Confidence | 3.4 score on a scale | Standard Deviation 0.5 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Patient Reported Questionnaires - Hypoglycemia Confidence | 3.4 score on a scale | Standard Deviation 0.5 |
| Sensor-Augmented Pump (SAP) | Patient Reported Questionnaires - Hypoglycemia Confidence | 3.4 score on a scale | Standard Deviation 0.5 |
Other Pre-specified
Patient Reported Questionnaires - Hypoglycemia Fear Survey
The Hypoglycemia Fear Survey measures several dimensions of fear of hypoglycemia among adults with type 1 diabetes. It consists of a 15-item Behavior subscale that measures behaviors involved in avoidance and over-treatment of hypoglycemia and a 18-item Worry subscale that measures anxiety and fear surrounding hypoglycemia. Scores will be calculated overall and for the worry subscale. Score scale 0-4; A higher score indicates more fear.
Time frame: at 12 week visit for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Patient Reported Questionnaires - Hypoglycemia Fear Survey | 0.9 score on a scale | Standard Deviation 0.6 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Patient Reported Questionnaires - Hypoglycemia Fear Survey | 1.0 score on a scale | Standard Deviation 0.6 |
| Sensor-Augmented Pump (SAP) | Patient Reported Questionnaires - Hypoglycemia Fear Survey | 1.0 score on a scale | Standard Deviation 0.6 |
Other Pre-specified
Patient Reported Questionnaires - System Usability
A 10-item questionnaire that measures overall perceived usability of a system and is technology-agnostic. Score scale 0-100; Higher score indicates better usability
Time frame: at 12 week visit for each arm of the crossover
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hybrid Closed Loop Control (HCL) | Patient Reported Questionnaires - System Usability | 77 score on a scale | Standard Deviation 17 |
| Predictive Low-Glucose Insulin Suspension (PLGS) | Patient Reported Questionnaires - System Usability | 76 score on a scale | Standard Deviation 17 |
| Sensor-Augmented Pump (SAP) | Patient Reported Questionnaires - System Usability | 73 score on a scale | Standard Deviation 16 |