Borderline HypokalemiaPhase 2NCT02236598
The Effects of Potassium on Glucose Metabolism in African Americans
A Phase 2 study testing K+ supplement in people with Borderline Hypokalemia, run by Duke University at 1 site in United States.
Trial summary
African Americans suffer a disproportionately high risk of diabetes compared to other Americans. Reasons for race disparities in diabetes incidence are not completely understood. Read more about this study
- Who is it for?
- Ages 30 years and older
- Conditions the study is for
- Borderline Hypokalemia
- What is being tested?
- K+ supplement
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 61 participants
- Where
- 1 siteUnited States
- Study dates
- Jan 2015to 29 Feb 2016
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 30 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- To be eligible for inclusion in the study the following enrollment criteria must be met:
- Participants must be 30 years of age or older.
- They must have a diagnosis of prediabetes defined as a hemoglobin A1c between 5.7-6.5% measured at the initial screening visit.
- They must have a serum K+ of 3.3-4.0 mEq/L on 2 occasions, within a 18 month period, including at initial screening visit. If subject is just outside range for inclusion, PI may offer the subject the option to repeat their screening serum K+ measurement.
- The participant must be willing and capable of providing written informed consent.
- The participant must be available for follow-up and must at minimum have telephone access.
- Participants must be able to read/understand English.
Who cannot join
- Participants must not have any of the following:
- Participants must not have evidence of chronic kidney disease with an estimated Glomerular Filtration Rate (eGFR) < 60ml/min. All patients will be screened for eGFR at the enrollment visit.
- Participants must not have evidence of diabetes mellitus requiring treatment with medications prior to screening visit. The cannot have a random or post-challenge glucose ≥ 200mg/dl (from prior labs), A1c level ≥ 6.5% (from prior labs), prior physician diagnosis, or use of anti-diabetic medications. If participants have glucose levels in the diabetic range at screening visit, they will be eligible to continue in study as long as glucose levels are not > 200 mg/dl.
- Participants must not have a history of endoscopy-verified peptic ulcer disease with past history of either gastric or duodenal ulcer.
- Participants must not have evidence of cardiac arrhythmias, unstable angina or cardiac event within 6 months, congestive heart failure, or other conditions that might impact follow-up, based on the discretion of the principal investigator.
- Participants must not be pregnant or intend to get pregnant during the study period. The study intervention is safe for pregnant women, so serum pregnancy screening is not indicated; however, pregnant women are excluded because pregnancy affects glucose homeostasis, which will bias primary outcome measurement and damage scientific validity of the study.
Trial locations and contacts
1 site in 1 country.
United States1 site
Duke University Medical Center
Durham, North Carolina, 27710
About this study
African Americans suffer a disproportionately high risk of diabetes compared to other Americans. Reasons for race disparities in diabetes incidence are not completely understood. Although a difference in prevalence of obesity does explain a significant portion of the racial disparity in diabetes risk, it does not explain all of this disparity. Strategies to control the diabetes epidemic and reduce its racial disparity often overlook preventive measures. Currently, the most powerful known strategy for preventing diabetes is weight loss in the overweight/obese. However, because weight loss is often difficult to achieve and maintain, other opportunities to prevent diabetes should be identified, particularly in African Americans. Among potential novel opportunities is correction of low or low-normal potassium levels (hypokalemia). In secondary analyses, we have found low-normal potassium (K) to be a novel risk factor for diabetes; and we have found that this association between low-K and diabetes risk may be stronger in African Americans compared to whites. Therefore, a previously unrecognized alternative or adjunct strategy for preventing diabetes, particularly in African Americans, may involve correction of low or low-normal K levels (hypokalemia). Large-scale, adequately-powered, randomized controlled trials are needed to establish the effectiveness of this approach. However, prior to those trials, the pathophysiology of the association between low K and poor glucose metabolism must be understood. This pilot clinical trial will begin to determine the effect of K supplementation on measures of glucose metabolism in African Americans.
In this pilot clinical trial, 30 African Americans with prediabetes and a low-normal serum K [<4.0 milliequivalent/Liter (Eq/L)] will be randomized to K-supplements, 20mEq (2-10mEq tablets) twice daily or a matching placebo capsules twice daily. Prior to randomization, baseline measures will be taken including measures of glucose metabolism with a 3-hour oral glucose tolerance test (OGTT), baseline chemistries and a baseline 24-hour urinary potassium measurement. Patients will take the intervention daily and will undergo repeat testing of all of these measures at the end of a 3 month period. The primary endpoint will be change in glucose tolerance, as measured by change in glucose area-under-the-curve (AUC) of a 3-hour oral glucose tolerance test (OGTT). Secondary endpoints will include changes in fasting, 1-hour, and 2-hour post-challenge glucose levels, as well as measurements of insulin secretion and insulin sensitivity as measures by the oral glucose minimal model method.(1) The baseline data from this trial will allow us to quantify abnormalities in glucose metabolism in African Americans with prediabetes/early diabetes and low-normal serum K. The post-intervention data will provide estimates of the impact of K-supplements compared to no supplements on these abnormalities. Data derived from the pilot study will be used in the design of a larger scale, adequately powered clinical trial. This trial will also help to assess the feasibility of recruiting this target population.
With this pilot trial, we will begin to determine whether or not K-supplements, an inexpensive, well-tolerated, and simple intervention, could help to reduce diabetes risk among African Americans.
- Conditions
- Borderline Hypokalemia
- Being tested
- K+ supplement, Placebo
- Keywords
- borderline hypokalemia, glucose tolerance, insulin secretion, insulin sensitivity, fasting glucose, African American
- Medical subject headings
- Insulin Resistance
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
K+ supplementDrug
PlaceboDrug
| Study group | Role | What they receive |
|---|---|---|
| K+ supplementation | Experimental | K-supplement- Klor-Con® M10 is an immediately dispersing extended-release oral dosage form of potassium chloride containing 750 mg of microencapsulated potassium chloride, United States Pharmacopeia (USP) equivalent to 10 milliequivalent (mEq) of potassium in a tablet. Participants will be instructed to take two 10 mEq tablets twice daily in a blinded encapsulated form, for 3 months Receives: Drug: K+ supplement |
| Placebo | Experimental | Placebo - An inert powdered placebo will be identically encapsulated as the Klor-Con intervention tablets to maintain blinding. Participants will be instructed to take two tablets twice daily in a blinded encapsulated form, for 3 months
Subjects will be instructed to take the pills Receives: Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Change in Glucose Tolerance as Measured by Area-under-the-curve
Change in glucose tolerance, as measured by change in glucose area-under-the-curve (Area Under the Curve (AUC) - measured via the trapezoidal method) of 2 hours from the 3-hour Oral Glucose Tolerance Test (OGTT).
Measured: Baseline to 3 months
Secondary outcomes (3)
Changes in Fasting, 1-hour, and 2-hour Post-challenge Glucose Levels in mg/dL
Changes in fasting, 1-hour, and 2-hour post-challenge glucose levels in mg/dL
Measured: Baseline to 3 months
Changes in Insulin Secretion as Measured by 2-hour Insulin Area-under-the-curve (AUC)
Changes in Insulin Secretion as measured by 2-hour insulin area-under-the-curve (AUC - measured via the trapezoidal method) of 2 hours from the 3-hour OGTT.
Measured: Baseline to 3 months
Changes in Insulin Sensitivity
Matsuda Insulin Sensitivity Index was calculated as: 10,000 / square root of [fasting glucose x fasting insulin x mean glucose x mean insulin during Oral Glucose Tolerance Test]).
Measured: Baseline to 3 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Sep 2014 (estimated)
- Study startJan 2015
- Primary completion29 Feb 2016
- Study completion29 Feb 2016
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Borderline HypokalemiaStudies of the same condition, open and under way.
- More trials run by Duke UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 61 participants (actual)
Sponsor and investigators
- Lead sponsor
- Duke University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Ranee C Montgomery, MD, Principal investigator, Duke University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02236598
- Sponsor's protocol ID
- Pro00056374
- Status last verified
- Apr 2017
- First submitted
- 8 Sep 2014
- Last updated
- 23 May 2017
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- No
Publications
Chatterjee R, Davenport CA, Kwee L, D'Alessio D, Svetkey LP, Lin PH, Slentz CA, Ilkayeva O, Johnson J, Edelman D, Shah SH. Preliminary evidence of effects of potassium chloride on a metabolomic path to diabetes and cardiovascular disease. Metabolomics. 2020 Jun 18;16(7):75. doi: 10.1007/s11306-020-01696-w.
PubMed 32556595Chatterjee R, Slentz C, Davenport CA, Johnson J, Lin PH, Muehlbauer M, D'Alessio D, Svetkey LP, Edelman D. Effects of potassium supplements on glucose metabolism in African Americans with prediabetes: a pilot trial. Am J Clin Nutr. 2017 Dec;106(6):1431-1438. doi: 10.3945/ajcn.117.161570. Epub 2017 Nov 1.
PubMed 29092881
Study at a glance
From the registry record, last updated by the sponsor on 23 May 2017. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- The Effects of Potassium on Glucose Metabolism in African Americans
- ClinicalTrials.gov ID
- NCT02236598
- Acronym / sponsor ID
- Pro00056374
- Conditions
- Borderline Hypokalemia
- Keywords
- borderline hypokalemia, glucose tolerance, insulin secretion, insulin sensitivity, fasting glucose, African American
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 61 participants (actual)
- Lead sponsor
- Duke UniversityUniversity, hospital or other
- Study start
- Jan 2015
- Primary completion
- 29 Feb 2016 (actual)
- Study completion
- 29 Feb 2016 (actual)
- First posted
- 10 Sep 2014 (estimated)
- Results
- Posted 23 May 2017
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
African Americans suffer a disproportionately high risk of diabetes compared to other Americans. Reasons for race disparities in diabetes incidence are not completely understood. Although a difference in prevalence of obesity does explain a significant portion of the racial disparity in diabetes risk, it does not explain all of this disparity. Strategies to control the diabetes epidemic and reduce its racial disparity often overlook preventive measures. Currently, the most powerful known strategy for preventing diabetes is weight loss in the overweight/obese. However, because weight loss is often difficult to achieve and maintain, other opportunities to prevent diabetes should be identified, particularly in African Americans. Among potential novel opportunities is correction of low or low-normal potassium levels (hypokalemia). In secondary analyses, we have found low-normal potassium (K) to be a novel risk factor for diabetes; and we have found that this association between low-K and diabetes risk may be stronger in African Americans compared to whites. Therefore, a previously unrecognized alternative or adjunct strategy for preventing diabetes, particularly in African Americans, may involve correction of low or low-normal K levels (hypokalemia). Large-scale, adequately-powered, randomized controlled trials are needed to establish the effectiveness of this approach. However, prior to those trials, the pathophysiology of the association between low K and poor glucose metabolism must be understood. This pilot clinical trial will begin to determine the effect of K supplementation on measures of glucose metabolism in African Americans.
In this pilot clinical trial, 30 African Americans with prediabetes and a low-normal serum K [<4.0 milliequivalent/Liter (Eq/L)] will be randomized to K-supplements, 20mEq (2-10mEq tablets) twice daily or a matching placebo capsules twice daily. Prior to randomization, baseline measures will be taken including measures of glucose metabolism with a 3-hour oral glucose tolerance test (OGTT), baseline chemistries and a baseline 24-hour urinary potassium measurement. Patients will take the intervention daily and will undergo repeat testing of all of these measures at the end of a 3 month period. The primary endpoint will be change in glucose tolerance, as measured by change in glucose area-under-the-curve (AUC) of a 3-hour oral glucose tolerance test (OGTT). Secondary endpoints will include changes in fasting, 1-hour, and 2-hour post-challenge glucose levels, as well as measurements of insulin secretion and insulin sensitivity as measures by the oral glucose minimal model method.(1) The baseline data from this trial will allow us to quantify abnormalities in glucose metabolism in African Americans with prediabetes/early diabetes and low-normal serum K. The post-intervention data will provide estimates of the impact of K-supplements compared to no supplements on these abnormalities. Data derived from the pilot study will be used in the design of a larger scale, adequately powered clinical trial. This trial will also help to assess the feasibility of recruiting this target population.
With this pilot trial, we will begin to determine whether or not K-supplements, an inexpensive, well-tolerated, and simple intervention, could help to reduce diabetes risk among African Americans.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| K+ supplementation | Experimental | Drug: K+ supplementK-supplement- Klor-Con® M10 is an immediately dispersing extended-release oral dosage form of potassium chloride containing 750 mg of microencapsulated potassium chloride, United States Pharmacopeia (USP) equivalent to 10 milliequivalent (mEq) of potassium in a tablet. Participants will be instructed to take two 10 mEq tablets twice daily in a blinded encapsulated form, for 3 months |
| Placebo | Experimental | Drug: PlaceboPlacebo - An inert powdered placebo will be identically encapsulated as the Klor-Con intervention tablets to maintain blinding. Participants will be instructed to take two tablets twice daily in a blinded encapsulated form, for 3 months Subjects will be instructed to take the pills |
Who may qualify
- Ages
- 30 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (7 listed)
- Participants must be 30 years of age or older.
- They must have a diagnosis of prediabetes defined as a hemoglobin A1c between 5.7-6.5% measured at the initial screening visit.
- They must have a serum K+ of 3.3-4.0 mEq/L on 2 occasions, within a 18 month period, including at initial screening visit. If subject is just outside range for inclusion, PI may offer the subject the option to repeat their screening serum K+ measurement.
- The participant must be willing and capable of providing written informed consent.
- The participant must be available for follow-up and must at minimum have telephone access.
Key exclusion criteria (6 listed)
- Participants must not have any of the following:
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| K+ supplement | Drug | K+ supplementation |
| Placebo | Drug | Placebo |
Primary outcome
Change in Glucose Tolerance as Measured by Area-under-the-curve
Time frame: Baseline to 3 months
Change in glucose tolerance, as measured by change in glucose area-under-the-curve (Area Under the Curve (AUC) - measured via the trapezoidal method) of 2 hours from the 3-hour Oral Glucose Tolerance Test (OGTT).
3 secondary outcomes
Changes in Fasting, 1-hour, and 2-hour Post-challenge Glucose Levels in mg/dL
Time frame: Baseline to 3 months
Changes in Insulin Secretion as Measured by 2-hour Insulin Area-under-the-curve (AUC)
Time frame: Baseline to 3 months
Changes in Insulin Sensitivity
Time frame: Baseline to 3 months
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 23 May 2017.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 32556595Chatterjee R, Davenport CA, Kwee L, D'Alessio D, Svetkey LP, Lin PH, Slentz CA, Ilkayeva O, Johnson J, Edelman D, Shah SH. Preliminary evidence of effects of potassium chloride on a metabolomic path to diabetes and cardiovascular disease. Metabolomics. 2020 Jun 18;16(7):75. doi: 10.1007/s11306-020-01696-w.
- Derived from this study: PubMed 29092881Chatterjee R, Slentz C, Davenport CA, Johnson J, Lin PH, Muehlbauer M, D'Alessio D, Svetkey LP, Edelman D. Effects of potassium supplements on glucose metabolism in African Americans with prediabetes: a pilot trial. Am J Clin Nutr. 2017 Dec;106(6):1431-1438. doi: 10.3945/ajcn.117.161570. Epub 2017 Nov 1.
Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Ranee C Montgomery, MD principal investigator
Duke University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing K+ supplement in people with Borderline Hypokalemia, run by Duke University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 7 inclusion and 6 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 23 May 2017. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 23 May 2017). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Change in Glucose Tolerance as Measured by Area-under-the-curve (time frame: Baseline to 3 months). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02236598, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 23 May 2017.