Diabetes Mellitus, Type 1, Overweight and Obesity
Conditions
Keywords
Type 1 diabetes, T1D, Type 1 diabetes mellitus (T1DM), weight management, overweight, obese
Brief summary
An initial pilot and feasibility study will be conducted using a Sequential, Multiple Assignment, Randomized Trial (SMART) design to identify acceptable and effective dietary strategies to optimize both glycemic control and weight management in young adults with Type 1 diabetes (T1D). This pilot trial will include a ten-and-a-half month behavioral intervention, with co-primary outcomes of glycemic control (HbA1C and hypoglycemia) and weight loss. The pilot trial will assess acceptability and adherence to three distinct, evidence-based dietary approaches designed to address weight management and glycemic control. Behavioral counseling strategies, use of carbohydrate counting for insulin dosing, and encouragement of physical activity will be the same across the three dietary approaches. COVID-19 PROVISIONS: Due to restrictions in place on in-person visits due to COVID-19 precautions, some subjects may remain in the study longer than 10.5 months. As of June 2020, the study transitioned to a completely virtual format. Those who were due for a measurement visit during the time that research activities were halted, prior to the approval of the virtual procedures, remained on the diet they were currently assigned to, supported by bi-weekly Registered Dietitian (RD) counseling, until they were able to be scheduled for a virtual visit.
Detailed description
Eight-four participants will be randomized in total; 42 at the University of North Carolina (UNC), 42 at Stanford. COVID-19 Provisions: Due to impacts of COVID-19, the study was forced to cease recruitment early. 40 subjects were randomized at UNC and 29 were randomized at Stanford, for a total of 69 subjects across sites. Procedures (methods): Three distinct dietary approaches will be tested. Dietary approaches are as follows: Diet 1: hypocaloric, moderate low fat (30% calories from fat) weight management based on the Look AHEAD study Diet 2: hypocaloric, low carbohydrate (15-20% calories from carbohydrate, 59-63% as total fat (\<10% saturated fat, at least 37% monounsaturated fat, remaining as polyunsaturated fat) Diet 3: advice to select a healthy Mediterranean dietary pattern with no caloric restriction Participants will complete measurement visits at baseline (-14 days), 3 mos, 6.5 mos, and 10 mos. All visits transitioned to a virtual format as of 6/2020 due to COVID-19 provisions. Participants will complete a total of 23 intervention sessions over an approximately 10-and-a-half month period (Eight longer sessions (teleconference) and 15 telephone check-ins) Participants will be randomized to one of the three diets for a minimum of a three-and-a-half month period. Re-randomization is possible following the 3 month and/or 6.5 month measurement visits. Re-randomization is based on acceptability of diet (self-report), non-severe hypoglycemic events (self-report), and not achieving significant weight change (defined as losing at least 2% of body weight from previous study visit), and worsening glycemic control (increase in Hemoglobin A1c of \>/= 0.5% from previous study visit). Re-randomization will occur after the 14-day continuous glucose monitoring (CGM) wear period that will be initiated at each measurement visit.
Interventions
BEHAVIORALHypocaloric, low carbohydrate diet
Participants will be advised on use of a hypocaloric, low carbohydrate diet using lifestyle counseling to include motivational interviewing and problem solving skills training strategies.
BEHAVIORALHypocaloric, moderate low fat diet
Participants will be advised on use of a hypocaloric, moderate low fat diet using lifestyle counseling to include motivational interviewing and problem solving skills training strategies.
BEHAVIORALMediterranean diet, no caloric restriction
Participants will be advised on use of a healthy Mediterranean-based eating plan using lifestyle counseling to include motivational interviewing and problem solving skills training strategies.
Sponsors
National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK)
University of North Carolina, Chapel Hill
Study design
Allocation
RANDOMIZED
Intervention model
SEQUENTIAL
Primary purpose
TREATMENT
Masking
NONE
Intervention model description
This initial pilot and feasibility study uses a Sequential, Multiple Assignment, Randomized Trial (SMART) design to identify acceptable and effective dietary strategies to optimize both glycemic control and weight management. The study will be done at UNC and Stanford. Sequential randomization will occur at 0, 3.5, and 7 months. Following the baseline measurement visit and two week run-in period, participants will be randomized to one of three diets (stratified by site with block size of 4). Using a priori decision rules at 3.5 and 7 months post-initial randomization, those for whom the assigned diet is not acceptable or effective will be re-randomized (or re-assigned if only one diet remains untried). 10.5 months of follow-up time allows for evaluation of the effect of diets on initial weight loss and on early maintenance of initial weight loss. Decision criteria for re-randomization will incorporate clinical outcomes (glycemic control and weight change) and acceptability of the diet.
Eligibility
Sex/Gender
ALL
Age
19 Years to 30 Years
Healthy volunteers
No
Inclusion criteria
* Individuals 19-30 years old at enrollment * History of Type 1 diabetes for greater than one year * Latest hemoglobin A1c less than 13% * BMI of 27-39
Exclusion criteria
* Individuals with other metabolic disorders, unstable thyroid disease, diagnosed eating disorder, prohibitive strict dietary restrictions or those with other serious condition that renders participation inappropriate * Individuals who have experience diabetic ketoacidosis (DKA) or severe hypoglycemia requiring outside assistance in the last 6 months * Females who are pregnant, breastfeeding, have delivered a baby in the last 12 months, or are planning to become pregnant during the study period. * Individuals unwilling to follow any of the three study diets * Individuals who monitor blood glucose less than 3 times a day
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in Time in Clinical Hypoglycemia - Randomization 3 | 2 weeks of wear from 6.5 Month (Measurement 3) Visit, 2 weeks of wear from 10 Month (Measurement 4) Visit | Change in the percent of time spent in clinical hypoglycemia (54-69 mg/dl) during CGM wear time will be assessed between the two weeks of wear from CGM insertion at Measurement 3 Visit and from CGM insertion at Measurement 4 Visit. |
| Change in Weight - Randomization 3 | 6.5 Month (Measurement 3) Visit, 10 Month (Measurement 4) Visit | Weight in kilograms will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period. |
| Change in HbA1C - Randomization 1 | Baseline (-14 Days prior to Randomization 1 Visit), 3 Month (Measurement 2) Visit | HbA1c will be measured from a blood sample collected from participants. Blood will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period. |
| Change in HbA1C - Randomization 2 | 3 Month (Measurement 2) Visit, 6.5 Month (Measurement 3) Visit | HbA1c will be measured from a blood sample collected from participants. Blood will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period. |
| Change in HbA1C - Randomization 3 | 6.5 Month (Measurement 3) Visit, 10 Month (Measurement 4) Visit | HbA1c will be measured from a blood sample collected from participants. Blood will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period. |
| Change in Time in Clinical Hypoglycemia - Randomization 1 | 2 weeks of wear from Baseline Visit (-14 Days), 2 weeks of wear from 3 Month (Measurement 2) Visit | Change in the percent of time spent in clinical hypoglycemia (54-69 mg/dl) during Continuous Glucose Monitor (CGM) wear time will be assessed between the two weeks of wear from CGM insertion at Baseline Visit (-14 days) and the two weeks of wear from the insertion of the CGM at Measurement Visit 2. |
| Change in Time in Clinical Hypoglycemia - Randomization 2 | 2 weeks of wear from 3 Month (Measurement 2) Visit, 2 weeks of wear from 6.5 Month (Measurement 3) Visit | Change in the percent of time spent in clinical hypoglycemia (54-69 mg/dl) during CGM wear time will be assessed between the two weeks of wear from CGM insertion at Measurement 2 Visit and from CGM insertion at Measurement 3 Visit. |
| Change in Weight - Randomization 1 | Baseline (-14 Days prior to Randomization 1 Visit), 3 Month (Measurement 2) Visit | Weight in kilograms will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period. |
| Change in Weight - Randomization 2 | 3 Month (Measurement 2) Visit, 6.5 Month (Measurement 3) Visit | Weight in kilograms will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Body Fat - Randomization 2 | 3 Month (Measurement 2) Visit, 6.5 Month (Measurement 3) Visit | Percent fat mass and percent fat free mass were measured via a dual-energy x-ray absorptiometry (DXA) scan at the beginning and end of this time three-and-a-half-month time period. COVID-19 PROVISIONS: Due to precautions required to prevent the spread of COVID-19, all in-person visits were discontinued as of 3/25/2020. As of this date, DXA scans at both sites were discontinued. Analysis on existing data continued, but no new DXA data were collected. |
| Change in Body Fat - Randomization 3 | 6.5 Month (Measurement 3) Visit, 10 Month (Measurement 4) Visit | Percent fat mass and percent fat free mass were measured via a dual-energy x-ray absorptiometry (DXA) scan at the beginning and end of this time three-and-a-half-month time period. COVID-19 PROVISIONS: Due to precautions required to prevent the spread of COVID-19, all in-person visits were discontinued as of 3/25/2020. As of this date, DXA scans at both sites were discontinued. Analysis on existing data continued, but no new DXA data were collected. |
| Change in Time in Target Glucose Range - Randomization 1 | 2 weeks of wear from 3 Month (Measurement 2) Visit, 2 weeks of wear from 6.5 Month (Measurement 3) Visit | Change in percent of time spent in a pre-defined range of relative euglycemia (70-180 mg/dl, for a person with Type 1 diabetes) during CGM wear time, will be assessed between the two weeks of wear from CGM insertion at Baseline Visit (-14 days) and the two weeks of wear from CGM insertion at Measurement Visit 2. |
| Change in Time in Target Glucose Range - Randomization 2 | 2 weeks of wear from 3 Month (Measurement 2) Visit, 2 weeks of wear from 6.5 Month (Measurement 3) Visit | Change in percent of time spent in a pre-defined range of relative euglycemia (70-180 mg/dl, for a person with Type 1 diabetes) during CGM wear time, will be assessed between the two weeks of wear from CGM insertion at Measurement 2 Visit and from CGM insertion at Measurement 3 Visit. |
| Change in Time in Target Glucose Range - Randomization 3 | 2 weeks of wear from 6.5 Month (Measurement 3) Visit, 2 weeks of wear from 10 Month (Measurement 4) Visit | Change in percent of time spent in a pre-defined range of relative euglycemia (70-180 mg/dl, for a person with Type 1 diabetes) during CGM wear time, will be assessed between the two weeks of wear from CGM insertion at Measurement 3 Visit and from CGM insertion at Measurement 4 Visit. |
| Change in Body Fat - Randomization 1 | Baseline (-14 Days prior to Randomization 1 Visit), 3 Month (Measurement 2) Visit | Percent fat mass and percent fat free mass were measured via a dual-energy x-ray absorptiometry (DXA) scan at the beginning and end of this time three-and-a-half-month time period. COVID-19 PROVISIONS: Due to precautions required to prevent the spread of COVID-19, all in-person visits were discontinued as of 3/25/2020. As of this date, DXA scans at both sites were discontinued. Analysis on existing data continued, but no new DXA data were collected. |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Hypocaloric, Low Carbohydrate Behavioral intervention to include lifestyle counseling on hypocaloric, low carbohydrate diet (15-20% calories from carbohydrate, 59-63% as total fat (\<10% saturated fat, at least 37% monounsaturated fat, remaining as polyunsaturated fat). Using a priori decision rules at 3.5 and 7 months post-initial randomization, those for whom the diet assigned is not acceptable or is not effective will be re-randomized. | 23 |
| Hypocaloric, Moderate Low Fat Behavioral intervention to include lifestyle counseling on hypocaloric, moderate low fat diet (30% calories from fat) weight management based on the Look AHEAD study. Using a priori decision rules at 3.5 and 7 months post-initial randomization, those for whom the diet assigned is not acceptable or is not effective will be re-randomized. | 24 |
| Mediterranean, no Caloric Restriction Behavioral intervention to include lifestyle counseling on selecting a healthy Mediterranean diet, no caloric restriction. Using a priori decision rules at 3.5 and 7 months post-initial randomization, those for whom the diet assigned is not acceptable or is not effective will be re-randomized. | 21 |
| Total | 68 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 |
|---|---|---|---|---|
| Diet Period 1 (Randomization 1) | Lost to Follow-up | 0 | 6 | 2 |
| Diet Period 1 (Randomization 1) | Withdrawal by Subject | 4 | 1 | 7 |
| Diet Period 2 (Randomization 2) | Lost to Follow-up | 0 | 2 | 3 |
| Diet Period 2 (Randomization 2) | Withdrawal by Subject | 2 | 0 | 0 |
| Diet Period 3 (Randomization 3) | Withdrawal by Subject | 0 | 0 | 1 |
Baseline characteristics
| Characteristic | Hypocaloric, Low Carbohydrate | Hypocaloric, Moderate Low Fat | Mediterranean, no Caloric Restriction | Total |
|---|---|---|---|---|
| Age, Continuous | 25.5 years STANDARD_DEVIATION 3.3 | 24.9 years STANDARD_DEVIATION 2.8 | 26.1 years STANDARD_DEVIATION 3.2 | 25.5 years STANDARD_DEVIATION 3.1 |
| Body fat | 39.4 Percent body fat | 39.8 Percent body fat | 41.6 Percent body fat | 40.4 Percent body fat |
| Ethnicity (NIH/OMB) Hispanic or Latino | 2 Participants | 5 Participants | 4 Participants | 11 Participants |
| Ethnicity (NIH/OMB) Not Hispanic or Latino | 21 Participants | 19 Participants | 17 Participants | 57 Participants |
| Ethnicity (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Hemoglobin A1c (%) | 7.3 percent glycated hemoglobin STANDARD_DEVIATION 1.5 | 8.2 percent glycated hemoglobin STANDARD_DEVIATION 1.3 | 8.2 percent glycated hemoglobin STANDARD_DEVIATION 1.3 | 7.9 percent glycated hemoglobin STANDARD_DEVIATION 1.4 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 1 Participants | 1 Participants | 0 Participants | 2 Participants |
| Race (NIH/OMB) Black or African American | 3 Participants | 1 Participants | 2 Participants | 6 Participants |
| Race (NIH/OMB) More than one race | 1 Participants | 1 Participants | 4 Participants | 6 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 1 Participants | 0 Participants | 1 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 1 Participants | 1 Participants | 2 Participants | 4 Participants |
| Race (NIH/OMB) White | 17 Participants | 19 Participants | 13 Participants | 49 Participants |
| Region of Enrollment United States | 23 Participants | 24 Participants | 21 Participants | 68 Participants |
| Sex: Female, Male Female | 15 Participants | 14 Participants | 20 Participants | 49 Participants |
| Sex: Female, Male Male | 8 Participants | 10 Participants | 1 Participants | 19 Participants |
| Time in clinical hypoglycemia | 3.5 Percent of time | 3.3 Percent of time | 4.1 Percent of time | 3.6 Percent of time |
| Time in target glucose range | 54.1 Percent of time STANDARD_DEVIATION 23.5 | 48.1 Percent of time STANDARD_DEVIATION 19.3 | 48.0 Percent of time STANDARD_DEVIATION 23 | 50.0 Percent of time STANDARD_DEVIATION 21.7 |
| Weight (kg) | 86.2 kilograms STANDARD_DEVIATION 10.7 | 91.9 kilograms STANDARD_DEVIATION 15.4 | 90.2 kilograms STANDARD_DEVIATION 15.6 | 89.4 kilograms STANDARD_DEVIATION 14 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 43 | 0 / 39 | 0 / 48 |
| other Total, other adverse events | 5 / 43 | 1 / 39 | 8 / 48 |
| serious Total, serious adverse events | 1 / 43 | 1 / 39 | 0 / 48 |
Outcome results
Primary
Change in HbA1C - Randomization 1
HbA1c will be measured from a blood sample collected from participants. Blood will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period.
Time frame: Baseline (-14 Days prior to Randomization 1 Visit), 3 Month (Measurement 2) Visit
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in HbA1C - Randomization 1 | -0.03 Percent glycated hemoglobin | Standard Deviation 0.55 |
| Hypocaloric, Moderate Low Fat | Change in HbA1C - Randomization 1 | -0.48 Percent glycated hemoglobin | Standard Deviation 0.83 |
| Mediterranean, no Caloric Restriction | Change in HbA1C - Randomization 1 | 0.37 Percent glycated hemoglobin | Standard Deviation 0.88 |
p-value: 0.02ANOVA
Primary
Change in HbA1C - Randomization 2
HbA1c will be measured from a blood sample collected from participants. Blood will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period.
Time frame: 3 Month (Measurement 2) Visit, 6.5 Month (Measurement 3) Visit
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in HbA1C - Randomization 2 | -0.11 Percent glycated hemoglobin | Standard Deviation 0.65 |
| Hypocaloric, Moderate Low Fat | Change in HbA1C - Randomization 2 | -0.008 Percent glycated hemoglobin | Standard Deviation 0.52 |
| Mediterranean, no Caloric Restriction | Change in HbA1C - Randomization 2 | -0.36 Percent glycated hemoglobin | Standard Deviation 0.66 |
p-value: 0.38ANOVA
Primary
Change in HbA1C - Randomization 3
HbA1c will be measured from a blood sample collected from participants. Blood will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period.
Time frame: 6.5 Month (Measurement 3) Visit, 10 Month (Measurement 4) Visit
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in HbA1C - Randomization 3 | 0.25 Percent glycated hemoglobin | Standard Deviation 0.72 |
| Hypocaloric, Moderate Low Fat | Change in HbA1C - Randomization 3 | 0.72 Percent glycated hemoglobin | Standard Deviation 1.7 |
| Mediterranean, no Caloric Restriction | Change in HbA1C - Randomization 3 | -0.16 Percent glycated hemoglobin | Standard Deviation 0.74 |
p-value: 0.18ANOVA
Primary
Change in Time in Clinical Hypoglycemia - Randomization 1
Change in the percent of time spent in clinical hypoglycemia (54-69 mg/dl) during Continuous Glucose Monitor (CGM) wear time will be assessed between the two weeks of wear from CGM insertion at Baseline Visit (-14 days) and the two weeks of wear from the insertion of the CGM at Measurement Visit 2.
Time frame: 2 weeks of wear from Baseline Visit (-14 Days), 2 weeks of wear from 3 Month (Measurement 2) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for continuous glucose monitoring.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Time in Clinical Hypoglycemia - Randomization 1 | -0.30 Percent of time | Standard Deviation 4.1 |
| Hypocaloric, Moderate Low Fat | Change in Time in Clinical Hypoglycemia - Randomization 1 | 0.65 Percent of time | Standard Deviation 5.4 |
| Mediterranean, no Caloric Restriction | Change in Time in Clinical Hypoglycemia - Randomization 1 | -0.45 Percent of time | Standard Deviation 1.7 |
p-value: 0.79ANOVA
Primary
Change in Time in Clinical Hypoglycemia - Randomization 2
Change in the percent of time spent in clinical hypoglycemia (54-69 mg/dl) during CGM wear time will be assessed between the two weeks of wear from CGM insertion at Measurement 2 Visit and from CGM insertion at Measurement 3 Visit.
Time frame: 2 weeks of wear from 3 Month (Measurement 2) Visit, 2 weeks of wear from 6.5 Month (Measurement 3) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for continuous glucose monitoring.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Time in Clinical Hypoglycemia - Randomization 2 | 0.2 Percent of time | Standard Deviation 3.2 |
| Hypocaloric, Moderate Low Fat | Change in Time in Clinical Hypoglycemia - Randomization 2 | 1.4 Percent of time | Standard Deviation 4.2 |
| Mediterranean, no Caloric Restriction | Change in Time in Clinical Hypoglycemia - Randomization 2 | 2.6 Percent of time | Standard Deviation 4.9 |
Comparison: The proposed sample size of n=72 was sufficient to ensure 60% power to detect a moderate effect size (Cohen h=0.68) and 80% to detect a large effect size (Cohen h=0.85) at a significance level of 0.10 for comparing difference in change among the 3 diets. By design, our primary goal for this pilot work is to inform the final efficacy design of a fully powered SMART, and the pilot SMART was therefore not designed to be fully powered for all analyses.p-value: 0.39ANOVA
Primary
Change in Time in Clinical Hypoglycemia - Randomization 3
Change in the percent of time spent in clinical hypoglycemia (54-69 mg/dl) during CGM wear time will be assessed between the two weeks of wear from CGM insertion at Measurement 3 Visit and from CGM insertion at Measurement 4 Visit.
Time frame: 2 weeks of wear from 6.5 Month (Measurement 3) Visit, 2 weeks of wear from 10 Month (Measurement 4) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for continuous glucose monitoring.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Time in Clinical Hypoglycemia - Randomization 3 | 0.086 Percent of time | Standard Deviation 2.5 |
| Hypocaloric, Moderate Low Fat | Change in Time in Clinical Hypoglycemia - Randomization 3 | 0.97 Percent of time | Standard Deviation 4.4 |
| Mediterranean, no Caloric Restriction | Change in Time in Clinical Hypoglycemia - Randomization 3 | -0.47 Percent of time | Standard Deviation 5.3 |
p-value: 0.75ANOVA
Primary
Change in Weight - Randomization 1
Weight in kilograms will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period.
Time frame: Baseline (-14 Days prior to Randomization 1 Visit), 3 Month (Measurement 2) Visit
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Weight - Randomization 1 | -1.6 kilograms | Standard Deviation 3.4 |
| Hypocaloric, Moderate Low Fat | Change in Weight - Randomization 1 | -1.8 kilograms | Standard Deviation 5.7 |
| Mediterranean, no Caloric Restriction | Change in Weight - Randomization 1 | -1.5 kilograms | Standard Deviation 3.2 |
p-value: 0.98ANOVA
Primary
Change in Weight - Randomization 2
Weight in kilograms will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period.
Time frame: 3 Month (Measurement 2) Visit, 6.5 Month (Measurement 3) Visit
Population: Completers for each diet period were participants who had sufficient data to be rerandomized. However, one participant on the Mediterranean diet who had insufficient data to be rerandomized had available weight data and was included in the weight analysis. Therefore, there is one more participant assigned to the Mediterranean diet for the weight analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Weight - Randomization 2 | 0.27 kilograms | Standard Deviation 3.8 |
| Hypocaloric, Moderate Low Fat | Change in Weight - Randomization 2 | 0.99 kilograms | Standard Deviation 4.1 |
| Mediterranean, no Caloric Restriction | Change in Weight - Randomization 2 | 0.86 kilograms | Standard Deviation 3 |
p-value: 0.85ANOVA
Primary
Change in Weight - Randomization 3
Weight in kilograms will be obtained at measurement visits at the beginning and end of this three-and-a-half month time period.
Time frame: 6.5 Month (Measurement 3) Visit, 10 Month (Measurement 4) Visit
Population: Data for one participant on the Mediterranean diet was excluded from analysis.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Weight - Randomization 3 | 0.68 kilograms | Standard Deviation 2.4 |
| Hypocaloric, Moderate Low Fat | Change in Weight - Randomization 3 | -0.85 kilograms | Standard Deviation 2.3 |
| Mediterranean, no Caloric Restriction | Change in Weight - Randomization 3 | -0.64 kilograms | Standard Deviation 3.4 |
p-value: 0.4ANOVA
Secondary
Change in Body Fat - Randomization 1
Percent fat mass and percent fat free mass were measured via a dual-energy x-ray absorptiometry (DXA) scan at the beginning and end of this time three-and-a-half-month time period. COVID-19 PROVISIONS: Due to precautions required to prevent the spread of COVID-19, all in-person visits were discontinued as of 3/25/2020. As of this date, DXA scans at both sites were discontinued. Analysis on existing data continued, but no new DXA data were collected.
Time frame: Baseline (-14 Days prior to Randomization 1 Visit), 3 Month (Measurement 2) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for dual-energy x-ray absorptiometry, which was discontinued following the transition to a virtual protocol due to COVID-19.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Body Fat - Randomization 1 | -0.87 Percent body fat | Standard Deviation 1.5 |
| Hypocaloric, Moderate Low Fat | Change in Body Fat - Randomization 1 | -0.058 Percent body fat | Standard Deviation 1.2 |
| Mediterranean, no Caloric Restriction | Change in Body Fat - Randomization 1 | -0.57 Percent body fat | Standard Deviation 1.8 |
p-value: 0.66ANOVA
Secondary
Change in Body Fat - Randomization 2
Percent fat mass and percent fat free mass were measured via a dual-energy x-ray absorptiometry (DXA) scan at the beginning and end of this time three-and-a-half-month time period. COVID-19 PROVISIONS: Due to precautions required to prevent the spread of COVID-19, all in-person visits were discontinued as of 3/25/2020. As of this date, DXA scans at both sites were discontinued. Analysis on existing data continued, but no new DXA data were collected.
Time frame: 3 Month (Measurement 2) Visit, 6.5 Month (Measurement 3) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for dual-energy x-ray absorptiometry, which was discontinued following the transition to a virtual protocol due to COVID-19.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Body Fat - Randomization 2 | -0.38 Percentage of body fat | Standard Deviation 2.7 |
| Hypocaloric, Moderate Low Fat | Change in Body Fat - Randomization 2 | -0.28 Percentage of body fat | Standard Deviation 1.7 |
| Mediterranean, no Caloric Restriction | Change in Body Fat - Randomization 2 | 0.05 Percentage of body fat | Standard Deviation 2.1 |
p-value: 0.96ANOVA
Secondary
Change in Body Fat - Randomization 3
Percent fat mass and percent fat free mass were measured via a dual-energy x-ray absorptiometry (DXA) scan at the beginning and end of this time three-and-a-half-month time period. COVID-19 PROVISIONS: Due to precautions required to prevent the spread of COVID-19, all in-person visits were discontinued as of 3/25/2020. As of this date, DXA scans at both sites were discontinued. Analysis on existing data continued, but no new DXA data were collected.
Time frame: 6.5 Month (Measurement 3) Visit, 10 Month (Measurement 4) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for dual-energy x-ray absorptiometry, which was discontinued following the transition to a virtual protocol due to COVID-19.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Body Fat - Randomization 3 | 1.4 Percent body fat | Standard Deviation 0.7 |
| Hypocaloric, Moderate Low Fat | Change in Body Fat - Randomization 3 | 0.1 Percent body fat | — |
| Mediterranean, no Caloric Restriction | Change in Body Fat - Randomization 3 | -0.9 Percent body fat | — |
p-value: 0.34ANOVA
Secondary
Change in Time in Target Glucose Range - Randomization 1
Change in percent of time spent in a pre-defined range of relative euglycemia (70-180 mg/dl, for a person with Type 1 diabetes) during CGM wear time, will be assessed between the two weeks of wear from CGM insertion at Baseline Visit (-14 days) and the two weeks of wear from CGM insertion at Measurement Visit 2.
Time frame: 2 weeks of wear from 3 Month (Measurement 2) Visit, 2 weeks of wear from 6.5 Month (Measurement 3) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for continuous glucose monitoring.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Time in Target Glucose Range - Randomization 1 | 6.3 Percent of time | Standard Deviation 19.1 |
| Hypocaloric, Moderate Low Fat | Change in Time in Target Glucose Range - Randomization 1 | 3.8 Percent of time | Standard Deviation 15.1 |
| Mediterranean, no Caloric Restriction | Change in Time in Target Glucose Range - Randomization 1 | -0.96 Percent of time | Standard Deviation 13.1 |
p-value: 0.58ANOVA
Secondary
Change in Time in Target Glucose Range - Randomization 2
Change in percent of time spent in a pre-defined range of relative euglycemia (70-180 mg/dl, for a person with Type 1 diabetes) during CGM wear time, will be assessed between the two weeks of wear from CGM insertion at Measurement 2 Visit and from CGM insertion at Measurement 3 Visit.
Time frame: 2 weeks of wear from 3 Month (Measurement 2) Visit, 2 weeks of wear from 6.5 Month (Measurement 3) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for continuous glucose monitoring.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Time in Target Glucose Range - Randomization 2 | -0.60 Percent of time | Standard Deviation 14.5 |
| Hypocaloric, Moderate Low Fat | Change in Time in Target Glucose Range - Randomization 2 | 0.90 Percent of time | Standard Deviation 14.4 |
| Mediterranean, no Caloric Restriction | Change in Time in Target Glucose Range - Randomization 2 | 1.0 Percent of time | Standard Deviation 9 |
p-value: 0.95ANOVA
Secondary
Change in Time in Target Glucose Range - Randomization 3
Change in percent of time spent in a pre-defined range of relative euglycemia (70-180 mg/dl, for a person with Type 1 diabetes) during CGM wear time, will be assessed between the two weeks of wear from CGM insertion at Measurement 3 Visit and from CGM insertion at Measurement 4 Visit.
Time frame: 2 weeks of wear from 6.5 Month (Measurement 3) Visit, 2 weeks of wear from 10 Month (Measurement 4) Visit
Population: The number of participants analyzed is fewer than the number of participants who completed the randomization period in each diet group due to missing data for continuous glucose monitoring.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Hypocaloric, Low Carbohydrate | Change in Time in Target Glucose Range - Randomization 3 | -2.1 Percent of time | Standard Deviation 19 |
| Hypocaloric, Moderate Low Fat | Change in Time in Target Glucose Range - Randomization 3 | -18.4 Percent of time | Standard Deviation 27 |
| Mediterranean, no Caloric Restriction | Change in Time in Target Glucose Range - Randomization 3 | 1.1 Percent of time | Standard Deviation 14.3 |
p-value: 0.08ANOVA