Chronic Kidney Diseases, High Blood Pressure
Conditions
Keywords
Racial disparities, Hypertension, Diet, Kidney disease
Brief summary
The purpose of this study is to determine cultural and disease-related barriers and facilitators to following the Dietary Approaches to Stop Hypertension (DASH) dietary pattern among Black Americans with moderate chronic kidney disease (CKD) and test the impact of a behavioral diet counseling intervention on DASH diet adherence, blood pressure, and CKD-relevant outcomes.
Detailed description
Excess cardiovascular disease (CVD) mortality among Black Americans with CKD is a significant US public health disparity. Compared to their White counterparts, Blacks develop CKD earlier in life and Blacks with CKD are 3 times more likely to progress to kidney failure necessitating dialysis or kidney transplantation, and are 1.5 times more likely to die prematurely from CVD. Hypertension, which is also more prevalent, more severe, and less often controlled in Blacks with CKD compared to Whites, is a leading cause of CKD and CVD, and a major contributor to the racial disparity in CVD mortality. Thus, improving hypertension in Blacks with CKD could have a profound positive impact on an important minority health issue. The DASH diet lowers BP and reduces CVD risk in patients with hypertension and has a greater effect on BP in Blacks compared to Whites. However, the effect of the DASH diet on BP in Blacks with CKD has not been established. First, investigators will conduct a qualitative study to identify self-perceived barriers and facilitators of DASH diet adherence among Blacks with moderate CKD. Then, investigators will conduct feasibility, acceptability, and preliminary efficacy testing of a disease-sensitive, culturally-appropriate diet counseling intervention on DASH adherence and blood pressure in Blacks with CKD. Prior to the clinical trial portion of this project Qualitative Focus Groups were held to identify self-perceived barriers and facilitators of DASH diet adherence among African Americans with CKD. Three to 4 groups of 6-8 participants were asked semi-structured questions to determine self-perceived sociocultural barriers and facilitators of DASH diet adherence and disease-specific factors that may influence their ability and willingness to follow a DASH-style diet. The information in the rest of this record pertains to the clinical trial portion of the project.
Interventions
BEHAVIORALDASH diet counseling
Culturally-appropriate, disease-sensitive counseling intervention to enhance DASH diet adherence in Blacks with CKD compared to standard of care condition
Sponsors
Duke University
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
NONE
Eligibility
Sex/Gender
ALL
Age
21 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Black race (self-identified) * ≥21 years old * CKD defined as an eGFR of 30-59 ml/min/1.73m2
Exclusion criteria
* History of kidney transplant * Pregnant of breast-feeding * Risk factors for hyperkalemia including insulin-dependent diabetes mellitus, diabetes with poor blood glucose control (A1C \>10), baseline serum potassium ≥4.8 mg/dl, and serum bicarbonate \<18 mg/dl * History of hypertension in the preceding 6 months defined as serum potassium greater than 5.1 mg/dl * Risk for hypotension or severe hypertension (SBP \<120 or ≥180 or DBP ≥110 mmHg) * History of kidney transplant * Lack of English language proficiency
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Change in 24 Hour Urine Urea Nitrogen Concentration | Baseline to 12 weeks | Change was measured by determining the difference in 24 hour urine urea nitrogen concentration at 12 weeks (end of treatment) from baseline value. |
| Number of Group Counseling Sessions Attended by Participants Randomized to the Treatment Arm | Up to 12 weeks | — |
| Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | Baseline, 1 month, 3 months, 6 months | Number of randomized participants who provided blood and urine biospecimens, clinic and 24-hour ambulatory blood pressure measurements, and 24-hour dietary recall data during scheduled data collection visits at baseline, 1 month, 3 months, and 6 months. |
| Change in 24-hour Mean Systolic Blood Pressure | Baseline to 12 weeks | Change was measured by determining the difference in 24-hr mean systolic blood pressure (mmHg) obtained at 12 weeks (end of treatment) from baseline value. |
| Change in Serum Potassium Concentration | Baseline to 12 weeks | Change was measured by determining the difference in serum potassium at 12 weeks (end of treatment) from baseline value. |
| Change in 24 Hour Urine Sodium Concentration | Baseline to 12 weeks | Change was measured by determining the difference in 24 hour urine sodium concentration at 12 weeks (end of treatment) from baseline value. |
| Change in 24 Hour Urine Phosphorus Concentration | Baseline to 12 weeks | Change was measured by determining the difference in 24 hour urine phosphorus concentration at 12 weeks (end of treatment) from baseline value. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Body Weight | Baseline to 12 weeks | Change was measured by determining the difference in body weight obtained at 12 weeks (end of treatment) from baseline value. |
| Change in Mean Clinic Systolic Blood Pressure From 12 Weeks (End of Treatment) to 24 Week Observation | 12 weeks to 24 weeks | Change was measured by determining the difference in mean clinic systolic blood pressure (mmHg) obtained at 24 weeks from 12 weeks. |
| Change in Body Weight From 12 Weeks (End of Treatment) to 24 Week Observation | 12 weeks to 24 weeks | Change was measured by determining the difference in body weight obtained at 24 weeks from 12 weeks. |
| Change in DASH Diet Score From 12 Weeks (End of Treatment) to 24 Week Observation | 12 weeks to 24 weeks | Change was measured by determining the difference in DASH diet score obtained at 24 weeks from 12 weeks. The DASH score, ranging from 8 to 40 points with eight components, focuses on food and nutrients for managing hypertension. The eight components are fruits, vegetables, nuts and legumes, whole grains, low-fat dairy, sodium, red and processed meats, and sweetened beverages. A higher score indicates better diet quality. |
| Change in DASH Diet Score From Baseline to 12 Weeks (End of Treatment) | Baseline to 12 weeks | Change was measured by determining the difference in DASH diet score obtained at 24 weeks from 12 weeks. The DASH score, ranging from 8 to 40 points with eight components, focuses on food and nutrients for managing hypertension. The eight components are fruits, vegetables, nuts and legumes, whole grains, low-fat dairy, sodium, red and processed meats, and sweetened beverages. A higher score indicates better diet quality. |
| Change in Clinic Mean Systolic Blood Pressure | Baseline to 12 weeks | Change was measured by determining the difference in clinic mean systolic blood pressure (mmHg) obtained at 12 weeks (end of treatment) from baseline value. |
Countries
United States
Participant flow
Recruitment details
Patients at a single academic medical center were recruited by invitation via their electronic patient portal or mailed letter.
Pre-assignment details
Of 204 individuals who completed the pre-screening survey, 158 were eligible for further screening, 86 consented to the study, and 31 met final inclusion criteria and were randomized to the intervention or control group.
Participants by arm
| Arm | Count |
|---|---|
| Behavioral Diet Counseling Groups of 4-6 participants will attend 12 weekly dietitian-led counseling sessions and receive coaching on practical strategies to enhance DASH diet adherence and reduce daily sodium intake.
DASH diet counseling: Culturally-appropriate, disease-sensitive counseling intervention to enhance DASH diet adherence in Blacks with CKD compared to standard of care condition | 16 |
| Standard of Care Participants will meet one-on-one with the study dietitian for a single 30- minute encounter and be advised to limit daily sodium intake per current clinical practice guidelines for hypertension in patients with CKD. Educational handouts and tip sheets about practical strategies to reduce dietary sodium will be distributed.
DASH diet counseling: Culturally-appropriate, disease-sensitive counseling intervention to enhance DASH diet adherence in Blacks with CKD compared to standard of care condition | 15 |
| Total | 31 |
Withdrawals & dropouts
| Period | Reason | FG000 | FG001 |
|---|---|---|---|
| Overall Study | Lost to Follow-up | 1 | 0 |
| Overall Study | Physician Decision | 1 | 0 |
| Overall Study | Relocated out of state | 1 | 0 |
Baseline characteristics
| Characteristic | Behavioral Diet Counseling | Total | Standard of Care |
|---|---|---|---|
| Age, Continuous | 70.9 years STANDARD_DEVIATION 6.7 | 71.8 years STANDARD_DEVIATION 6.5 | 72.7 years STANDARD_DEVIATION 6.2 |
| Race (NIH/OMB) American Indian or Alaska Native | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Asian | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Black or African American | 16 Participants | 31 Participants | 15 Participants |
| Race (NIH/OMB) More than one race | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Native Hawaiian or Other Pacific Islander | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) Unknown or Not Reported | 0 Participants | 0 Participants | 0 Participants |
| Race (NIH/OMB) White | 0 Participants | 0 Participants | 0 Participants |
| Region of Enrollment United States | 16 Participants | 31 Participants | 15 Participants |
| Sex: Female, Male Female | 12 Participants | 23 Participants | 11 Participants |
| Sex: Female, Male Male | 4 Participants | 8 Participants | 4 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 16 | 0 / 15 |
| other Total, other adverse events | 4 / 16 | 3 / 15 |
| serious Total, serious adverse events | 0 / 16 | 0 / 15 |
Outcome results
Primary
Change in 24-hour Mean Systolic Blood Pressure
Change was measured by determining the difference in 24-hr mean systolic blood pressure (mmHg) obtained at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Data not collected on 3 participants in the Behavioral Diet Counseling arm and 4 participants in the Standard of Care arm.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in 24-hour Mean Systolic Blood Pressure | -0.9 mmHg | Standard Deviation 16.1 |
| Standard of Care | Change in 24-hour Mean Systolic Blood Pressure | 4.0 mmHg | Standard Deviation 9.1 |
p-value: 0.396895% CI: [-16.8, 6.9]t-test, 2 sided
Primary
Change in 24 Hour Urine Phosphorus Concentration
Change was measured by determining the difference in 24 hour urine phosphorus concentration at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in 24 Hour Urine Phosphorus Concentration | -73.0 mg/dL/day | Standard Deviation 180.9 |
| Standard of Care | Change in 24 Hour Urine Phosphorus Concentration | -62.3 mg/dL/day | Standard Deviation 197.3 |
p-value: 0.882195% CI: [-157.8, 136.4]t-test, 2 sided
Primary
Change in 24 Hour Urine Sodium Concentration
Change was measured by determining the difference in 24 hour urine sodium concentration at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in 24 Hour Urine Sodium Concentration | -8.2 mmol/L/day | Standard Deviation 37.1 |
| Standard of Care | Change in 24 Hour Urine Sodium Concentration | -19.9 mmol/L/day | Standard Deviation 75.3 |
Primary
Change in 24 Hour Urine Sodium Concentration
Change was measured by determining the difference in 24 hour urine sodium concentration at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in 24 Hour Urine Sodium Concentration | -8.2 mmol/L/day | Standard Deviation 37.1 |
| Standard of Care | Change in 24 Hour Urine Sodium Concentration | -19.9 mmol/L/day | Standard Deviation 75.25 |
p-value: 0.067395% CI: [-34.2, 58.6]t-test, 2 sided
Primary
Change in 24 Hour Urine Urea Nitrogen Concentration
Change was measured by determining the difference in 24 hour urine urea nitrogen concentration at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in 24 Hour Urine Urea Nitrogen Concentration | -0.5 mcg/mL | Standard Deviation 2.5 |
| Standard of Care | Change in 24 Hour Urine Urea Nitrogen Concentration | -1.07 mcg/mL | Standard Deviation 3.9 |
p-value: 0.647995% CI: [-2, 3.1]t-test, 2 sided
Primary
Change in Serum Potassium Concentration
Change was measured by determining the difference in serum potassium at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in Serum Potassium Concentration | 0.06 mmol/L | Standard Deviation 0.46 |
| Standard of Care | Change in Serum Potassium Concentration | 0.01 mmol/L | Standard Deviation 0.53 |
p-value: 0.0792695% CI: [-0.33, 0.44]t-test, 2 sided
Primary
Number of Group Counseling Sessions Attended by Participants Randomized to the Treatment Arm
Time frame: Up to 12 weeks
Population: Only relevant to the Behavioral Diet Counseling arm.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Number of Group Counseling Sessions Attended by Participants Randomized to the Treatment Arm | 8.9 sessions per participant | Standard Deviation 4.2 |
Primary
Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints
Number of randomized participants who provided blood and urine biospecimens, clinic and 24-hour ambulatory blood pressure measurements, and 24-hour dietary recall data during scheduled data collection visits at baseline, 1 month, 3 months, and 6 months.
Time frame: Baseline, 1 month, 3 months, 6 months
| Arm | Measure | Group | Value (COUNT_OF_PARTICIPANTS) |
|---|---|---|---|
| Behavioral Diet Counseling | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | 3 months | 14 Participants |
| Behavioral Diet Counseling | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | 1 month | 14 Participants |
| Behavioral Diet Counseling | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | 6 months | 13 Participants |
| Behavioral Diet Counseling | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | Baseline | 16 Participants |
| Standard of Care | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | 6 months | 15 Participants |
| Standard of Care | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | Baseline | 15 Participants |
| Standard of Care | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | 1 month | 15 Participants |
| Standard of Care | Number of Participants Who Completed Data Collection Visits at Scheduled Study Timepoints | 3 months | 14 Participants |
Secondary
Change in Body Weight
Change was measured by determining the difference in body weight obtained at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in Body Weight | 0.16 kg | Standard Deviation 1.65 |
| Standard of Care | Change in Body Weight | -1.18 kg | Standard Deviation 3.76 |
p-value: 0.237495% CI: [-0.97, 3.6]t-test, 2 sided
Secondary
Change in Body Weight From 12 Weeks (End of Treatment) to 24 Week Observation
Change was measured by determining the difference in body weight obtained at 24 weeks from 12 weeks.
Time frame: 12 weeks to 24 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in Body Weight From 12 Weeks (End of Treatment) to 24 Week Observation | -0.77 kg | Standard Deviation 1.97 |
| Standard of Care | Change in Body Weight From 12 Weeks (End of Treatment) to 24 Week Observation | 0.62 kg | Standard Deviation 1.62 |
p-value: 0.054695% CI: [-2.82, 0.03]t-test, 2 sided
Secondary
Change in Clinic Mean Systolic Blood Pressure
Change was measured by determining the difference in clinic mean systolic blood pressure (mmHg) obtained at 12 weeks (end of treatment) from baseline value.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in Clinic Mean Systolic Blood Pressure | 4.6 mmHg | Standard Deviation 21.5 |
| Standard of Care | Change in Clinic Mean Systolic Blood Pressure | -2.4 mmHg | Standard Deviation 22.2 |
p-value: 0.404495% CI: [-10, 24]t-test, 2 sided
Secondary
Change in DASH Diet Score From 12 Weeks (End of Treatment) to 24 Week Observation
Change was measured by determining the difference in DASH diet score obtained at 24 weeks from 12 weeks. The DASH score, ranging from 8 to 40 points with eight components, focuses on food and nutrients for managing hypertension. The eight components are fruits, vegetables, nuts and legumes, whole grains, low-fat dairy, sodium, red and processed meats, and sweetened beverages. A higher score indicates better diet quality.
Time frame: 12 weeks to 24 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in DASH Diet Score From 12 Weeks (End of Treatment) to 24 Week Observation | 0.25 score on a scale | Standard Deviation 1.41 |
| Standard of Care | Change in DASH Diet Score From 12 Weeks (End of Treatment) to 24 Week Observation | 0.25 score on a scale | Standard Deviation 1 |
p-value: 195% CI: [-0.98, 0.98]t-test, 2 sided
Secondary
Change in DASH Diet Score From Baseline to 12 Weeks (End of Treatment)
Change was measured by determining the difference in DASH diet score obtained at 24 weeks from 12 weeks. The DASH score, ranging from 8 to 40 points with eight components, focuses on food and nutrients for managing hypertension. The eight components are fruits, vegetables, nuts and legumes, whole grains, low-fat dairy, sodium, red and processed meats, and sweetened beverages. A higher score indicates better diet quality.
Time frame: Baseline to 12 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in DASH Diet Score From Baseline to 12 Weeks (End of Treatment) | 0.15 score on a scale | Standard Deviation 1.26 |
| Standard of Care | Change in DASH Diet Score From Baseline to 12 Weeks (End of Treatment) | -0.14 score on a scale | Standard Deviation 1.69 |
p-value: 195% CI: [-0.89, 1.49]t-test, 2 sided
Secondary
Change in Mean Clinic Systolic Blood Pressure From 12 Weeks (End of Treatment) to 24 Week Observation
Change was measured by determining the difference in mean clinic systolic blood pressure (mmHg) obtained at 24 weeks from 12 weeks.
Time frame: 12 weeks to 24 weeks
Population: Participants with data collected at both timepoints.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Behavioral Diet Counseling | Change in Mean Clinic Systolic Blood Pressure From 12 Weeks (End of Treatment) to 24 Week Observation | -7.9 mmHg | Standard Deviation 13.9 |
| Standard of Care | Change in Mean Clinic Systolic Blood Pressure From 12 Weeks (End of Treatment) to 24 Week Observation | -5.2 mmHg | Standard Deviation 13.3 |
p-value: 0.618895% CI: [-13.71, 8.33]t-test, 2 sided