Diabetes Mellitus, Diet
Conditions
Keywords
Diabetes Mellitus (type 2), Diet, Glycohemoglobin, Lipids, Kidney Function, Glycemic Index, Dietary Protein, Dietary Carbohydrate
Brief summary
We will determine the metabolic response to a Low Biologically Available Glucose Diet (LoBAG30) in subjects currently receiving the maximum dose of metformin as monotherapy in whom the glycohemoglobin is not at an acceptable level (\>8.0%). Our hypothesis is that introduction of a LoBAG30 diet to subjects currently treated with a full therapeutic dose of metformin will improve blood glucose control in people who have not achieved an acceptable total glycohemoglobin on metformin alone.
Detailed description
Subjects will ingest a control diet (55% carbohydrate (CHO), 15% protein, 30% fat) or a LoBAG30 diet (30% CHO, 30% protein, 40% fat) in a parallel design with block randomization in pairs of two. Subjects will return to the study center twice each week while on the diets to have blood glucose, glycohemoglobin, lactate, weight and blood pressure measured, and to have urine assayed for urea and creatinine. At the beginning and end of the 5 week study period, the subjects will be admitted to the study center for 28 hours during which time blood will be drawn for 24 hour profiles of glucose, insulin, other hormones and several metabolites. For those subjects randomized to the LoBAG30 arm of the study, the control diet will be given during the first 24 hour study period; the assigned diet will be given at the end of the 5 week period.
Interventions
OTHERLoBAG30 diet
A LoBAG30 diet consists of 30% of total energy intake as carbohydrate, 30% protein, and 40% fat.
OTHERControl Diet
A control diet consists of 55% of total energy intake as carbohydrate, 15% protein, 30% fat
Sponsors
US Department of Veterans Affairs
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
50 Years to 70 Years
Healthy volunteers
No
Inclusion criteria
* People with type 2 diabetes mellitus who currently are receiving the maximal dose of metformin monotherapy (2500 mg/day). * These subjects will have had a stable glycohemoglobin (tGHb) in an unacceptably high range (8-11%) for at least 4 months prior to beginning the study. * Subjects with tGHB \> 11% (HbA1c \> 10%) will not be recruited into the study.
Exclusion criteria
* Hematological abnormalities * liver disease * kidney disease * macroalbuminuria (\>300 mg albumin/24 hours) * untreated thyroid disease * congestive heart failure * angina * life-threatening malignancies * proliferative retinopathy * severe diabetic neuropathy * peripheral vascular disease * serious psychological disorders * a body mass index \> 35 * and a fasting triglyceride of \>400 mg/dl. * Subjects taking slow-release metformin will not be studied. * Subjects taking medications other than metformin, known to affect fuel metabolism such as: * insulin * the sulfonylureas * glucagon-like peptide 1 (GLP-1) analogs and metabolic inhibitors * pramlintide * prednisone and similar steroids * thyroid hormone * antipsychotic medications * thiazide diuretics * medroxyprogesterone * high dose aspirin, also will be excluded. * If concentrations of serum folate, B12 or iron are low, the subject will be excluded from the study until corrected, i.e. until normal concentrations are recorded.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in %Hemoglobin A1c at 5 Weeks From Baseline | Baseline and 5 weeks after dietary intervention | Hemoglobin A1c measured before and after 5 weeks on the diet |
| Change in Total Glucose Area at 5 Weeks From Baseline | Baseline and 5 weeks after dietary intervention | The area response is measured using zero as baseline. The area is measured before dietary intervention, and following 5 weeks of dietary intervention. |
| Change in Body Weight at 5 Weeks From Baseline | baseline and 5 weeks after dietary intervention | Subjects were to remain weight stable. We expected less than 2 pound weight change over 5 weeks. Weight was measured before dietary intervention, and after 5 weeks of dietary intervention. |
| Change in Overnight Fasting Glucose Concentration at 5 Weeks From Baseline | baseline and 5 weeks after dietary intervention | Overnight fasting glucose concentration was measured before dietary intervention and after 5 weeks of dietary intervention. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Microalbumin Excretion | baseline and 5 weeks after dietary intervention | change in urinary albumin excretion was measured before dietary intervention and after 5 weeks of dietary intervention |
| Change in Fasting Triglycerides at 5 Weeks From Baseline | baseline and 5 weeks after dietary intervention | Overnight fasting triglycerides concentration was measured before dietary intervention and after 5 weeks of dietary intervention |
Countries
United States
Participant flow
Pre-assignment details
Proposed study design was 20 subjects, 10/arm. (Parallel arm design requested by grant Reviewers.) At the end of the funding period, 14 subjects had been enrolled and studied, 7 in each arm.
Participants by arm
| Arm | Count |
|---|---|
| LoBAG30 Diet A LoBAG30, weight maintenance diet 30% carbohydrate, 30% protein, and 40% fat. | 7 |
| Control Diet A weight maintenance, control diet consisting 55% carbohydrate, 15% protein, 30% fat | 7 |
| Total | 14 |
Baseline characteristics
| Characteristic | LoBAG30 Diet | Control Diet | Total |
|---|---|---|---|
| Age, Continuous | 62 years | 61 years | 61.6 years |
| Region of Enrollment United States | 7 participants | 7 participants | 14 participants |
| Sex: Female, Male Female | 0 Participants | 0 Participants | 0 Participants |
| Sex: Female, Male Male | 7 Participants | 7 Participants | 14 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | — / — | — / — |
| other Total, other adverse events | 0 / 0 | 0 / 0 |
| serious Total, serious adverse events | 0 / 7 | 0 / 7 |
Outcome results
Primary
Change in Body Weight at 5 Weeks From Baseline
Subjects were to remain weight stable. We expected less than 2 pound weight change over 5 weeks. Weight was measured before dietary intervention, and after 5 weeks of dietary intervention.
Time frame: baseline and 5 weeks after dietary intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| LoBAG30 Diet | Change in Body Weight at 5 Weeks From Baseline | -0.7 pounds | Standard Error 0.7 |
| Control Diet | Change in Body Weight at 5 Weeks From Baseline | -2.6 pounds | Standard Error 1 |
Primary
Change in %Hemoglobin A1c at 5 Weeks From Baseline
Hemoglobin A1c measured before and after 5 weeks on the diet
Time frame: Baseline and 5 weeks after dietary intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| LoBAG30 Diet | Change in %Hemoglobin A1c at 5 Weeks From Baseline | -0.9 Change in % A1c at 5 weeks from baseli | Standard Error 0.23 |
| Control Diet | Change in %Hemoglobin A1c at 5 Weeks From Baseline | -0.9 Change in % A1c at 5 weeks from baseli | Standard Error 0.16 |
Primary
Change in Overnight Fasting Glucose Concentration at 5 Weeks From Baseline
Overnight fasting glucose concentration was measured before dietary intervention and after 5 weeks of dietary intervention.
Time frame: baseline and 5 weeks after dietary intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| LoBAG30 Diet | Change in Overnight Fasting Glucose Concentration at 5 Weeks From Baseline | -22 mg/dl | Standard Error 16.5 |
| Control Diet | Change in Overnight Fasting Glucose Concentration at 5 Weeks From Baseline | -33 mg/dl | Standard Error 4.7 |
Primary
Change in Total Glucose Area at 5 Weeks From Baseline
The area response is measured using zero as baseline. The area is measured before dietary intervention, and following 5 weeks of dietary intervention.
Time frame: Baseline and 5 weeks after dietary intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| LoBAG30 Diet | Change in Total Glucose Area at 5 Weeks From Baseline | -957 mg hr/dl | Standard Error 302 |
| Control Diet | Change in Total Glucose Area at 5 Weeks From Baseline | -691 mg hr/dl | Standard Error 84 |
Secondary
Change in Fasting Triglycerides at 5 Weeks From Baseline
Overnight fasting triglycerides concentration was measured before dietary intervention and after 5 weeks of dietary intervention
Time frame: baseline and 5 weeks after dietary intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| LoBAG30 Diet | Change in Fasting Triglycerides at 5 Weeks From Baseline | -18 mg/dl | Standard Error 12.9 |
| Control Diet | Change in Fasting Triglycerides at 5 Weeks From Baseline | -24 mg/dl | Standard Error 9.9 |
Secondary
Microalbumin Excretion
change in urinary albumin excretion was measured before dietary intervention and after 5 weeks of dietary intervention
Time frame: baseline and 5 weeks after dietary intervention
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| LoBAG30 Diet | Microalbumin Excretion | -0.9 mg/day | Standard Error 4.2 |
| Control Diet | Microalbumin Excretion | -8.3 mg/day | Standard Error 3.5 |