Impaired Fasting Glucose (IFG), Impaired Glucose Tolerance (IGT), PreDiabetes
Conditions
Keywords
prediabetes, impaired fasting glucose, impaired glucose tolerance, metformin, nitric oxide
Brief summary
This study evaluates the effect of different doses of metformin on the function of endothelium in people with pre-diabetes. One group of the patients will receive metformin in dose: 1500 mg, the second one will receive 3000 mg/day. The parameters from healthy volunteers will be taken only at the study beginning to compare the test results with the parameters from patients with pre-diabetes. This group will be not treated with metformin (no intervention)
Detailed description
In addition to exercise and diet, metformin is a medicine used to treat diabetes mellitus (DM) and pre-diabetic (pre-DM) conditions. This drug improves insulin sensitivity in both groups of patients (DM and pre-DM) and as a result gives a reduction in blood glucose. However, studies also confirm the effect of metformin on the reduction of cardiovascular risk in patients with diabetes (UKPDStudy), regardless of the hypoglycaemic effect. The precise mechanism of action of the drug in this field is not clear. There is also no data on whether similar effects apply to patients with pre-diabetes. Although we know that this group of patients is also characterized by increased cardiovascular risk. One of the most important substances that are involved in vasodilation is nitric oxide (NO). Impairment of its secretion is an important signal of endothelial damage and is connected with cardiovascular complications. The impact of metformin on endothelial function in pre-diabetes patients is not known. We do not know the effect of the drug dose and its different serum concentration on the secretion of the dilators of the vessels, which are associated with endothelial function. The study involves patients with pre-diabetes who meet the inclusion criteria, have no contraindication to participate in the study (see exclusion criteria), and give their written consent after reading Information for the patient. The conditions (IFG, IGT) for participation in the study are confirmed by a diabetologist (principal investigator ) based on fasting glucose and OGTT (oral glucose tolerance test) with 75 mg of glucose. Metformin will be given in an increasing dose in accordance with the test protocol. After reaching a one-week treatment with a dose of 3 x 500 mg, patients will be assigned to group A -a continuation of a dose of 3 x 500 and group B- increase dose to 3 x 1000mg. Randomization depends on the identification number (ID). The patients with an even, second number in the PESEL (identification number) will be randomized to the A group, the patients with the second, odd number in the PESEL will be randomized to the group B. Here as an example: PESEL: 60010102823- 0 is as an even number so the patient will be randomized to the group A; PESEL: 61010102823- 1 is an odd number- the patient will be randomized to the group B. This PESEL number (ID) in Poland is given to every person shortly after birth and the researchers have no influence on it. In the final stage also patients from group B (metformin: 3 x 1000 mg), will back to the treatment dose of metformin 3 x 500 mg- to show the relationship between the dose, serum concentration of the metformin and its effect on the secretion of the measured substances. The healthy volunteers will be not treated with metformin. Patients will be reminded by phone about the increase in metformin dose as well as on control visits. The lack of possible treatment with proper doses of metformin due to poor drug tolerance will move the patient from group B to group A if such dose (3 x 500 mg) is well tolerated. The patient will be excluded from the study if no compliance or lack of contact with the patient will be recorded during the treatment period or if metformin dose: 3 x 500 mg will be characterized with bad tolerance. Information about: age, gender, BMI, cardiovascular risk factors, the current basic lab-tests, and pharmacotherapy will be recorded. The blood samples for: plasma metformin level and listed substances will be collected for patients with pre-diabetes as described below (see diagram). The basic parameters as well as NO indirect products concentrations will be assessed for healthy volunteers only once-at the beginning of the study. Test 1: NO(0) (indirect products) for patients before treatment start 3 weeks increasing dose of metformin to the final dose: 1500mg/day 3 x 500 mg (1500/day)- the dose is reached 3 weeks treatment 1500mg/day Tests 2: NO1(1500) and metformin concentration Randomization B:3 weeks increasing dose A: 6 weeks continuation with of metformin to the final a dose 3 x 500 mg dose 3 x 1000mg 3 x 1000mg (3000mg/day)- the dose is reached 3 weeks treatment 3000mg/day Tests 3: NO2(1000) or NO3(500) and metformin concentration for both groups 3 weeks treatment 1500mg/day for both groups Test 4: NO4 and metformin concentration Statistical analysis: For statistical analysis, the Statistica 12 program will be used (StatSoft Polska Sp. z o.o. www.statsoft.pl). The cut-off point for statistical significance (p) was determined at 0.05. To determine the statistical significance will be used tests compliant with the distribution of variables and data character (Student's t-test, Mann-Whitney test, chi-square test, Kruskal-Wallis ANOVA test). For analysis taking into account the duration of the study and determine the impact of relevant variables to achieve the appropriate concentration of nitric oxide will be used Cox proportional hazard regression. The goal of the optimal determination cut-off point for predictors will use ROC curves. Logistic regression was used to determine the independent predictors to obtain the desired concentration of nitric oxide. In order to determine the correlation, it will be used correlation of order Spearman's rank correlation coefficient or Pearson correlation coefficient.
Interventions
DRUGMetformin
for group A: 12 weeks metformin treatment in a final dose 3 x 500 mg for group B: 3 weeks metformin treatment in a dose 3 x 500 mg, next: 3 weeks metformin treatment in a final dose 3 x 1000mg, next: 3 weeks metformin treatment in a dose 3 x 500 mg.
Sponsors
Wroclaw Medical University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
BASIC_SCIENCE
Masking
SINGLE (Investigator)
Masking description
At the beginning of the study, patients are assigned a number by a nurse and are assigned to group A or B according to ID. When analyzing the results, the researchers only knows the numbers of blood samples.
Intervention model description
The group of patients taking the drug at the target dose of 3 x 1000 after 4 weeks returned to the dose of 3 x 500 mg. The group of patients taking the drug at the target dose 3 x 500 mg consequently had this dose during the whole study period. The basic parameters and biochemical parameters from healthy individuals at the beginning of the study were assessed to compare with patients with pre-diabetes. This group did not take the metformin and thus did not have further examination and lab-tests during the study.
Eligibility
Sex/Gender
ALL
Age
40 Years to 65 Years
Healthy volunteers
Yes
Inclusion criteria
for treated groups ( A or B): * age: 40-65 years; * pre-diabetic status based on fasting plasma glucose (FPG) and / or OGTT; * without metformin before; * without ischemic heart disease in history; * without a stroke in a history; * without PAOD (peripheral arterial occlusive disease) in a history; * without active cancer in a history
Exclusion criteria
for treated groups (A or B): * age \<40 or \>65; * diabetes; * taking metformin before study; * active cancer; * history of macro-angiopathy (ischemic heart disease, stroke or TIA, PAOD); * serious gastrointestinal disease that may affect metformin tolerance; * renal failure with GFR\<45 ml/min/1.73m2; * alanin transaminase \> 3 x ULN Inclusion criteria for healthy volunteers: * age: 40-65 years; * no carbo-hydrates disturbances (based on fasting plasma glucose (FPG) and/or OGTT); * without metformin before; * without ischemic heart disease in history; * without a stroke in a history; * without PAOD (peripheral arterial occlusive disease) in a history; * without active cancer in a history
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Serum Levels of Metformin at Different Time Points | 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start | the serum concentration of the studied drug-metformin |
| Serum Levels of Arginine at Different Time Points | Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start | arginine serum concentration |
| Serum Levels of ADMA at Different Time Points | before study start; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start | ADMA- asymmetric dimethylarginine-serum concentration |
| Serum Levels of SDMA at Different Time Points | Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start | SDMA-symmetric dimethylarginine-serum concentration |
| Serum Levels of Citrulline at Different Time Points | Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start | serum concentration of the citrulline |
| Serum Levels of DMA at Different Time Points | Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start | DMA- dimethylamine, serum concentration |
Countries
Poland
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Group A Patients with pre-diabetes; metformin dose 3 x 500 mg
Metformin: for group A: 12 weeks metformin treatment with a final dose 3 x 500 mg, after 3 weeks of the titration Total treatment time: 15 weeks | 14 |
| Group B Patients with pre-diabetes, max metformin dose 3 x 1000 mg
Metformin: for group B: 3 weeks metformin treatment with a dose 3 x 500 mg, after 3 weeks of the titration next: 3 weeks metformin treatment with a final dose 3 x 1000mg, after 3 weeks of the titration next: 3 weeks metformin treatment with a dose 3 x 500 mg. Total treatment time: 15 weeks | 11 |
| Group C healthy volunteers | 11 |
| Total | 36 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 | FG002 |
|---|---|---|---|---|
| After 6 Weeks of Treatment | Physician Decision | 0 | 2 | 0 |
| Before Treatment | drug intolerance | 2 | 1 | 0 |
| Before Treatment | Lost to Follow-up | 1 | 2 | 0 |
| Before Treatment | Physician Decision | 0 | 0 | 11 |
| Before Treatment | Withdrawal by Subject | 0 | 5 | 0 |
Baseline characteristics
| Characteristic | Total | Group A | Group B | Group C |
|---|---|---|---|---|
| ADMA | 0.53 µM STANDARD_DEVIATION 0.09 | 0.51 µM STANDARD_DEVIATION 0.09 | 0.53 µM STANDARD_DEVIATION 0.09 | 0.56 µM STANDARD_DEVIATION 0.1 |
| Age, Continuous | 51.97 years STANDARD_DEVIATION 8.67 | 50.64 years STANDARD_DEVIATION 8.85 | 55.73 years STANDARD_DEVIATION 8.27 | 49.90 years STANDARD_DEVIATION 8.37 |
| alanin transaminase | 28.11 U/l STANDARD_DEVIATION 16.74 | 28.13 U/l STANDARD_DEVIATION 14.01 | 35.45 U/l STANDARD_DEVIATION 20.51 | 19.11 U/l STANDARD_DEVIATION 12.06 |
| arginine | 115.48 µM STANDARD_DEVIATION 27.54 | 114.29 µM STANDARD_DEVIATION 28.15 | 110.37 µM STANDARD_DEVIATION 27.63 | 122.11 µM STANDARD_DEVIATION 27.96 |
| BMI | 29.89 kg/m^2 STANDARD_DEVIATION 5.21 | 31.49 kg/m^2 STANDARD_DEVIATION 5.26 | 30.75 kg/m^2 STANDARD_DEVIATION 4 | 26.99 kg/m^2 STANDARD_DEVIATION 5.43 |
| body mass | 90.52 kg STANDARD_DEVIATION 16.28 | 96.71 kg STANDARD_DEVIATION 13.74 | 92.36 kg STANDARD_DEVIATION 9.73 | 80.81 kg STANDARD_DEVIATION 20.64 |
| Citrulline | 36.11 µM STANDARD_DEVIATION 8.8 | 34.10 µM STANDARD_DEVIATION 9.84 | 38.33 µM STANDARD_DEVIATION 7.49 | 36.45 µM STANDARD_DEVIATION 8.82 |
| creatinine | 0.85 mg/dl STANDARD_DEVIATION 0.16 | 0.86 mg/dl STANDARD_DEVIATION 0.18 | 0.89 mg/dl STANDARD_DEVIATION 0.16 | 0.73 mg/dl STANDARD_DEVIATION 0.03 |
| DMA | 1.73 µM STANDARD_DEVIATION 0.55 | 1.77 µM STANDARD_DEVIATION 0.71 | 1.74 µM STANDARD_DEVIATION 0.48 | 1.67 µM STANDARD_DEVIATION 0.4 |
| family history for DM | 14 Participants | 7 Participants | 4 Participants | 3 Participants |
| Fasting Plasma Glucose (FPG) | 102.44 mg/dl STANDARD_DEVIATION 12.11 | 109.39 mg/dl STANDARD_DEVIATION 11.13 | 107.23 mg/dl STANDARD_DEVIATION 5.95 | 88.81 mg/dl STANDARD_DEVIATION 4.44 |
| HDL- high density lipoprotein | 52.58 mg/dl STANDARD_DEVIATION 14.38 | 49.86 mg/dl STANDARD_DEVIATION 12.07 | 50.73 mg/dl STANDARD_DEVIATION 14.35 | 57.91 mg/dl STANDARD_DEVIATION 16.82 |
| hypertension | 16 Participants | 7 Participants | 6 Participants | 3 Participants |
| LDL-low density lipoprotein | 116.75 mg/dl STANDARD_DEVIATION 26.2 | 125.29 mg/dl STANDARD_DEVIATION 30.79 | 106.95 mg/dl STANDARD_DEVIATION 23.78 | 115.70 mg/dl STANDARD_DEVIATION 19.91 |
| liver steatosis | 17 Participants | 7 Participants | 9 Participants | 1 Participants |
| nicotinism | 9 Participants | 3 Participants | 4 Participants | 2 Participants |
| Ornithine | 35.73 µM STANDARD_DEVIATION 12.51 | 34.77 µM STANDARD_DEVIATION 11.58 | 37.12 µM STANDARD_DEVIATION 15.71 | 35.57 µM STANDARD_DEVIATION 11.09 |
| Race and Ethnicity Not Collected | 0 Participants | — | — | — |
| Region of Enrollment Poland | 36 Participants | 14 Participants | 11 Participants | 11 Participants |
| SDMA | 0.41 µM STANDARD_DEVIATION 0.08 | 0.39 µM STANDARD_DEVIATION 0.07 | 0.41 µM STANDARD_DEVIATION 0.1 | 0.42 µM STANDARD_DEVIATION 0.08 |
| Sex: Female, Male Female | 14 Participants | 5 Participants | 3 Participants | 6 Participants |
| Sex: Female, Male Male | 22 Participants | 9 Participants | 8 Participants | 5 Participants |
| TCL- total cholesterol level | 198.50 mg/dl STANDARD_DEVIATION 39.71 | 207.21 mg/dl STANDARD_DEVIATION 50.22 | 184.91 mg/dl STANDARD_DEVIATION 34.19 | 201 mg/dl STANDARD_DEVIATION 27.47 |
| TG-triglicerydes | 135.53 mg/dl STANDARD_DEVIATION 58.54 | 133.29 mg/dl STANDARD_DEVIATION 62.77 | 136.82 mg/dl STANDARD_DEVIATION 66.63 | 137.09 mg/dl STANDARD_DEVIATION 49.2 |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk | EG002 affected / at risk |
|---|---|---|---|
| deaths Total, all-cause mortality | 0 / 15 | 0 / 21 | 0 / 11 |
| other Total, other adverse events | 3 / 15 | 2 / 21 | 0 / 11 |
| serious Total, serious adverse events | 0 / 15 | 0 / 21 | 0 / 11 |
Outcome results
Primary
Serum Levels of ADMA at Different Time Points
ADMA- asymmetric dimethylarginine-serum concentration
Time frame: before study start; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start
Population: Groups A and B -patients with pre-diabetes treated with different dose of the metformin, group C- healthy volunteers, no metformin
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Group A | Serum Levels of ADMA at Different Time Points | 6 weeks from the start of treatment | 0.51 µM | Standard Deviation 0.11 |
| Group A | Serum Levels of ADMA at Different Time Points | 12 weeks from the start of treatment | 0.52 µM | Standard Deviation 0.09 |
| Group A | Serum Levels of ADMA at Different Time Points | 15 weeks from the start of treatment | 0.50 µM | Standard Deviation 0.08 |
| Group B | Serum Levels of ADMA at Different Time Points | 6 weeks from the start of treatment | 0.57 µM | Standard Deviation 0.11 |
| Group B | Serum Levels of ADMA at Different Time Points | 12 weeks from the start of treatment | 0.55 µM | Standard Deviation 0.14 |
| Group B | Serum Levels of ADMA at Different Time Points | 15 weeks from the start of treatment | 0.52 µM | Standard Deviation 0.1 |
Primary
Serum Levels of Arginine at Different Time Points
arginine serum concentration
Time frame: Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start
Population: Groups A and B -patients with pre-diabetes treated with different dose of the metformin, group C- healthy volunteers, no metformin
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Group A | Serum Levels of Arginine at Different Time Points | 6 weeks from the start of treatment | 112.18 µM | Standard Deviation 53.42 |
| Group A | Serum Levels of Arginine at Different Time Points | 12 weeks from the start of treatment | 107.72 µM | Standard Deviation 13.93 |
| Group A | Serum Levels of Arginine at Different Time Points | 15 weeks from the start of treatment | 104.72 µM | Standard Deviation 34.21 |
| Group B | Serum Levels of Arginine at Different Time Points | 6 weeks from the start of treatment | 111.72 µM | Standard Deviation 36.89 |
| Group B | Serum Levels of Arginine at Different Time Points | 12 weeks from the start of treatment | 97.69 µM | Standard Deviation 38.76 |
| Group B | Serum Levels of Arginine at Different Time Points | 15 weeks from the start of treatment | 103.76 µM | Standard Deviation 19.76 |
Primary
Serum Levels of Citrulline at Different Time Points
serum concentration of the citrulline
Time frame: Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start
Population: Groups A and B -patients with pre-diabetes treated with different dose of the metformin, group C- healthy volunteers, no metformin
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Group A | Serum Levels of Citrulline at Different Time Points | 6 weeks from the start of treatment | 21.73 µM | Standard Deviation 6.66 |
| Group A | Serum Levels of Citrulline at Different Time Points | 12 weeks from the start of treatment | 25.95 µM | Standard Deviation 9.48 |
| Group A | Serum Levels of Citrulline at Different Time Points | 15 weeks from the start of treatment | 26.93 µM | Standard Deviation 9.71 |
| Group B | Serum Levels of Citrulline at Different Time Points | 6 weeks from the start of treatment | 28.08 µM | Standard Deviation 11.31 |
| Group B | Serum Levels of Citrulline at Different Time Points | 12 weeks from the start of treatment | 27.01 µM | Standard Deviation 15.38 |
| Group B | Serum Levels of Citrulline at Different Time Points | 15 weeks from the start of treatment | 29.77 µM | Standard Deviation 11.26 |
Primary
Serum Levels of DMA at Different Time Points
DMA- dimethylamine, serum concentration
Time frame: Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start
Population: Groups A and B -patients with pre-diabetes treated with different dose of the metformin, group C- healthy volunteers, no metformin
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Group A | Serum Levels of DMA at Different Time Points | 6 weeks from the start of treatment | 1.71 µM | Standard Deviation 0.31 |
| Group A | Serum Levels of DMA at Different Time Points | 12 weeks from the start of treatment | 1.63 µM | Standard Deviation 0.28 |
| Group A | Serum Levels of DMA at Different Time Points | 15 weeks from the start of treatment | 1.62 µM | Standard Deviation 0.34 |
| Group B | Serum Levels of DMA at Different Time Points | 6 weeks from the start of treatment | 2.07 µM | Standard Deviation 0.52 |
| Group B | Serum Levels of DMA at Different Time Points | 12 weeks from the start of treatment | 1.89 µM | Standard Deviation 0.43 |
| Group B | Serum Levels of DMA at Different Time Points | 15 weeks from the start of treatment | 1.84 µM | Standard Deviation 0.68 |
Primary
Serum Levels of Metformin at Different Time Points
the serum concentration of the studied drug-metformin
Time frame: 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start
Population: Group A and B- patients with pre-diabetes treated with different metformin dose (according to the information above as arm description) , group C- healthy volunteers, no metformin assessment as no treatment
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Group A | Serum Levels of Metformin at Different Time Points | 6 weeks from the start of treatment | 4.36 µM | Standard Deviation 2.36 |
| Group A | Serum Levels of Metformin at Different Time Points | 12 weeks from the start of treatment | 5.09 µM | Standard Deviation 2.29 |
| Group A | Serum Levels of Metformin at Different Time Points | 15 weeks from the start of treatment | 4.66 µM | Standard Deviation 3.73 |
| Group B | Serum Levels of Metformin at Different Time Points | 6 weeks from the start of treatment | 4.25 µM | Standard Deviation 2.58 |
| Group B | Serum Levels of Metformin at Different Time Points | 12 weeks from the start of treatment | 7.42 µM | Standard Deviation 4.77 |
| Group B | Serum Levels of Metformin at Different Time Points | 15 weeks from the start of treatment | 4.01 µM | Standard Deviation 4.01 |
Primary
Serum Levels of SDMA at Different Time Points
SDMA-symmetric dimethylarginine-serum concentration
Time frame: Baseline; 6 weeks from treatment start; 12 weeks from treatment start; 15 weeks from treatment start
Population: Groups A and B -patients with pre-diabetes treated with different dose of the metformin, group C- healthy volunteers, no metformin
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Group A | Serum Levels of SDMA at Different Time Points | 15 weeks from the start of treatment | 0.39 µM | Standard Deviation 0.07 |
| Group A | Serum Levels of SDMA at Different Time Points | 6 weeks from the start of treatment | 0.40 µM | Standard Deviation 0.08 |
| Group A | Serum Levels of SDMA at Different Time Points | 12 weeks from the start of treatment | 0.41 µM | Standard Deviation 0.08 |
| Group B | Serum Levels of SDMA at Different Time Points | 6 weeks from the start of treatment | 0.45 µM | Standard Deviation 0.08 |
| Group B | Serum Levels of SDMA at Different Time Points | 12 weeks from the start of treatment | 0.42 µM | Standard Deviation 0.08 |
| Group B | Serum Levels of SDMA at Different Time Points | 15 weeks from the start of treatment | 0.39 µM | Standard Deviation 0.06 |