Gout, Hyperuricemia
Conditions
Keywords
Diet, Nutrition, DASH, Gout, Hyperuricemia, Potassium, Uric acid, Trial, Blood pressure, Glucose, Lipid, Cholesterol, Weight, Arthritis, BMI, Body mass index, Fruit, Vegetable, Low fat dairy, Lean meat, Fiber
Brief summary
Unhealthy diet has long been associated with high uric acid levels and gout. The DASH diet may lower uric acid levels. This study will examine the effects of the DASH diet on uric acid in adults with a history of gout.
Detailed description
The public health burden of gout is substantial. Several lines of evidence suggest that a DASH diet might lower uric acid. However, there are no trials of the DASH diet in adults with gout. This trial is a cross-over study of the effects of a DASH-like diet on uric acid in adults with gout and hyperuricemia, who are not taking urate-lowering therapy. Perpetuated by the Western lifestyle and resulting obesity epidemic, the prevalence of gout has increased over the past few decades to 3.9% of US adults (8.3 million individuals). This prevalence increases with age to 9.3% of US adults over 60 years (4.7 million). Participants will be community-dwelling adults, aged 18+ with a baseline serum uric acid level of 7 mg/dL, who have a self-reported history of gout and are not taking urate lowering medications (e.g. allopurinol, febuxostat, probenecid). This trial is comprised of two study periods: (1) a dietitian-directed diet (DD) or (2) self-directed usual diet (SD). Each period lasts 4 weeks. All participants will participate in both periods, but half will undergo the dietitian-directed diet first while the other half will undergo the self-directed diet first. During the dietitian-directed diet, participants will receive $105/week of foods in a pattern that conforms to the DASH diet. The DASH diet emphasizes fruit, vegetables, lean meat, low fat dairy, and high fiber, while restricting red meat, sweets, and sugary beverages. During the self-directed diet, participants will be asked to eat their typical diet outside of the study. Investigators anticipate 40 participants in this study. The primary outcome is uric acid. Secondary outcomes of this study include: body mass index, systolic and diastolic blood pressure, fasting cholesterol, and fasting blood glucose. Both primary and secondary outcomes will be measured 3 times: (1) before the study begins (baseline), (2) after period 1 (at 4 weeks), and (3) after period 2 (at 8 weeks). Patient-reported outcomes, dietary compliance, and urine electrolytes will be assessed throughout the study as well. The primary comparison will be serum uric acid concentrations measured after the 4-week dietitian-directed diet versus uric acid concentrations measured after the 4-week self-directed diet (DD vs. SD). Comparisons will be made within person using generalized estimating equations (GEE) with and without adjustment for baseline uric acid concentration. Investigators will use GEE models for secondary outcomes as well.
Interventions
OTHERSubsidy for food purchases and dietitian education
$105/wk of DASH-like foods over 4 weeks purchased with the help of a dietitian in a proportion that reflects the DASH diet.
Sponsors
Massachusetts General Hospital
Beth Israel Deaconess Medical Center
Harvard Medical School (HMS and HSDM)
Rheumatology Research Foundation
Johns Hopkins University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
TREATMENT
Masking
DOUBLE (Investigator, Outcomes Assessor)
Masking description
Investigators will not know which assignment the participants were given. The laboratory measuring uric acid will not know which intervention the participants were assigned.
Intervention model description
Half of participants will be randomly assigned 1 of 2 potential sequences. All participants will ultimately participate in each study period, but the order will be randomly assigned 1:1.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Age \> 18-100 years Self-reported gout diagnosis Serum Uric Acid \> 7 mg/dL
Exclusion criteria
Recent or planned changes to urate lowering therapies (e.g. allopurinol, febuxostat, probenecid) Recent or planned changes to hypertension, lipid, or diabetes medications Patients with hyperkalemia (\>5 mmol/L) Chronic kidney disease (GFR \< 30 cc/min), kidney transplant, dialysis Gastro-intestinal conditions (e.g. history of gastric bypass surgery, active inflammatory bowel disease, malabsorption, or major GI resection) Active cancer treatment (e.g. radiation or chemotherapy) Diagnosis of any of the following in the past 6 months: heart attack, heart failure, angina, coronary bypass or angioplasty, or Chronic Obstructive Pulmonary Disease (COPD) Alcohol use over 14 drinks per week Inability to give informed consent Active use of warfarin, insulin, or chronic steroids (like prednisone) Terminal or mental illness
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Uric Acid Level | Baseline | Measured in serum |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Systolic Blood Pressure (mm Hg) | Baseline, 4-weeks, 8-weeks | — |
| Diastolic Blood Pressure (mm Hg) | At baseline, 4-weeks, 8-weeks | — |
| Fasting Blood Glucose (mg/dL) | Baseline, 4-weeks, 8-weeks | Measured in serum |
| Low Density Lipoprotein Cholesterol (mg/dL) | Baseline, 4-weeks, 8-weeks | Measured in serum |
| Body Mass Index (kg/m^2) | Baseline, 4-weeks, 8-weeks | Derived from baseline height, and serial weight measurements |
Countries
United States
Participant flow
Participants by arm
| Arm | Count |
|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet Participants will be provided $105/week ($15/day) to purchase foods in servings that correspond to the DASH diet and thus include fruits, vegetables, lean meat, low fat dairy, and high fiber foods. Participants will also be asked to restrict red meat, sweets, and sugary beverages during this intervention period. A dietitian will help participants order foods from a digital supermarket. Foods will be delivered to the Johns Hopkins ProHealth Research Clinic for weekly pick-up. This study period will last 4 weeks.
Subsidy for food purchases and dietitian education: $105/wk of DASH-like foods over 4 weeks purchased with the help of a dietitian in a proportion that reflects the DASH diet. | 22 |
| Self-Directed Diet Then Dietitian-Directed Diet Participants will be asked to consume their typical diet for 4 weeks. There will be no subsidy during this period. | 21 |
| Total | 43 |
Baseline characteristics
| Characteristic | Dietitian-Directed Diet Then Self-Directed Diet | Self-Directed Diet Then Dietitian-Directed Diet | Total |
|---|---|---|---|
| Age, Continuous | 57.5 mg/dL STANDARD_DEVIATION 13.3 | 60.5 mg/dL STANDARD_DEVIATION 10.7 | 59.0 mg/dL STANDARD_DEVIATION 12.1 |
| Race/Ethnicity, Customized Asian/Pacific Islander | 2 Participants | 3 Participants | 5 Participants |
| Race/Ethnicity, Customized Black/African American | 12 Participants | 9 Participants | 21 Participants |
| Race/Ethnicity, Customized Hispanic or Latino | 0 Participants | 0 Participants | 0 Participants |
| Race/Ethnicity, Customized White/Caucasian | 8 Participants | 9 Participants | 17 Participants |
| Region of Enrollment United States | 22 participants | 21 participants | 43 participants |
| Sex: Female, Male Female | 4 Participants | 4 Participants | 8 Participants |
| Sex: Female, Male Male | 18 Participants | 17 Participants | 35 Participants |
Adverse events
| Event type | EG000 affected / at risk | EG001 affected / at risk |
|---|---|---|
| deaths Total, all-cause mortality | 0 / 43 | 0 / 43 |
| other Total, other adverse events | 0 / 43 | 0 / 43 |
| serious Total, serious adverse events | 0 / 43 | 0 / 43 |
Outcome results
Primary
Uric Acid Level
Measured in serum
Time frame: At 4-weeks
Population: This was a crossover study. Data are presented by first period assignment. The 4-week results represent period 1.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Uric Acid Level | 7.67 mg/dL | Standard Deviation 1.25 |
| Self-Directed Diet Then Dietitian-Directed Diet | Uric Acid Level | 8.03 mg/dL | Standard Deviation 1.13 |
Primary
Uric Acid Level
Measured in serum
Time frame: Baseline
Population: This was a crossover design. All 43 participants underwent both interventions. The data is presented by first period assignment.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Uric Acid Level | 8.23 mg/dL | Standard Deviation 0.74 |
| Self-Directed Diet Then Dietitian-Directed Diet | Uric Acid Level | 8.03 mg/dL | Standard Deviation 0.79 |
Primary
Uric Acid Level
Measured in serum
Time frame: At 8-weeks
Population: This was a crossover design. Results are presented by period 1 assignment. The 8-week results represent the effect of the second period.
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Uric Acid Level | 7.75 mg/dL | Standard Deviation 1.15 |
| Self-Directed Diet Then Dietitian-Directed Diet | Uric Acid Level | 7.98 mg/dL | Standard Deviation 1.15 |
Secondary
Body Mass Index (kg/m^2)
Derived from baseline height, and serial weight measurements
Time frame: Baseline, 4-weeks, 8-weeks
Population: One person in the Dietitian-Directed Diet and then Self-Directed Diet did not provide a body mass index measurement during the follow-up visit.
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Body Mass Index (kg/m^2) | Baseline | 33.4 kg/m^2 | Standard Deviation 6.4 |
| Dietitian-Directed Diet Then Self-Directed Diet | Body Mass Index (kg/m^2) | Period 1 | 33.0 kg/m^2 | Standard Deviation 6.4 |
| Dietitian-Directed Diet Then Self-Directed Diet | Body Mass Index (kg/m^2) | Period 2 | 33.6 kg/m^2 | Standard Deviation 6.5 |
| Self-Directed Diet Then Dietitian-Directed Diet | Body Mass Index (kg/m^2) | Baseline | 33.5 kg/m^2 | Standard Deviation 7.5 |
| Self-Directed Diet Then Dietitian-Directed Diet | Body Mass Index (kg/m^2) | Period 1 | 33.6 kg/m^2 | Standard Deviation 7.8 |
| Self-Directed Diet Then Dietitian-Directed Diet | Body Mass Index (kg/m^2) | Period 2 | 33.5 kg/m^2 | Standard Deviation 8 |
Secondary
Diastolic Blood Pressure (mm Hg)
Time frame: At baseline, 4-weeks, 8-weeks
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Diastolic Blood Pressure (mm Hg) | Baseline | 74.9 mm Hg | Standard Deviation 11.3 |
| Dietitian-Directed Diet Then Self-Directed Diet | Diastolic Blood Pressure (mm Hg) | Period 1 | 76.1 mm Hg | Standard Deviation 11.9 |
| Dietitian-Directed Diet Then Self-Directed Diet | Diastolic Blood Pressure (mm Hg) | Period 2 | 77.3 mm Hg | Standard Deviation 11.7 |
| Self-Directed Diet Then Dietitian-Directed Diet | Diastolic Blood Pressure (mm Hg) | Baseline | 72.6 mm Hg | Standard Deviation 10.5 |
| Self-Directed Diet Then Dietitian-Directed Diet | Diastolic Blood Pressure (mm Hg) | Period 1 | 75.0 mm Hg | Standard Deviation 11.8 |
| Self-Directed Diet Then Dietitian-Directed Diet | Diastolic Blood Pressure (mm Hg) | Period 2 | 74.0 mm Hg | Standard Deviation 11.4 |
Secondary
Fasting Blood Glucose (mg/dL)
Measured in serum
Time frame: Baseline, 4-weeks, 8-weeks
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Fasting Blood Glucose (mg/dL) | Baseline | 93.0 mg/dL | Standard Deviation 11.6 |
| Dietitian-Directed Diet Then Self-Directed Diet | Fasting Blood Glucose (mg/dL) | Period 1 | 96.5 mg/dL | Standard Deviation 12.1 |
| Dietitian-Directed Diet Then Self-Directed Diet | Fasting Blood Glucose (mg/dL) | Period 2 | 97.1 mg/dL | Standard Deviation 12.7 |
| Self-Directed Diet Then Dietitian-Directed Diet | Fasting Blood Glucose (mg/dL) | Baseline | 103.0 mg/dL | Standard Deviation 18.1 |
| Self-Directed Diet Then Dietitian-Directed Diet | Fasting Blood Glucose (mg/dL) | Period 1 | 103.2 mg/dL | Standard Deviation 27.7 |
| Self-Directed Diet Then Dietitian-Directed Diet | Fasting Blood Glucose (mg/dL) | Period 2 | 97.6 mg/dL | Standard Deviation 16.6 |
Secondary
Low Density Lipoprotein Cholesterol (mg/dL)
Measured in serum
Time frame: Baseline, 4-weeks, 8-weeks
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Low Density Lipoprotein Cholesterol (mg/dL) | Period 2 | 107.5 mg/dL | Standard Deviation 33.8 |
| Dietitian-Directed Diet Then Self-Directed Diet | Low Density Lipoprotein Cholesterol (mg/dL) | Baseline | 109.0 mg/dL | Standard Deviation 31.1 |
| Dietitian-Directed Diet Then Self-Directed Diet | Low Density Lipoprotein Cholesterol (mg/dL) | Period 1 | 105.3 mg/dL | Standard Deviation 34.4 |
| Self-Directed Diet Then Dietitian-Directed Diet | Low Density Lipoprotein Cholesterol (mg/dL) | Period 1 | 113.4 mg/dL | Standard Deviation 41.5 |
| Self-Directed Diet Then Dietitian-Directed Diet | Low Density Lipoprotein Cholesterol (mg/dL) | Period 2 | 105.5 mg/dL | Standard Deviation 36.8 |
| Self-Directed Diet Then Dietitian-Directed Diet | Low Density Lipoprotein Cholesterol (mg/dL) | Baseline | 115.5 mg/dL | Standard Deviation 41.2 |
Secondary
Systolic Blood Pressure (mm Hg)
Time frame: Baseline, 4-weeks, 8-weeks
| Arm | Measure | Group | Value (MEAN) | Dispersion |
|---|---|---|---|---|
| Dietitian-Directed Diet Then Self-Directed Diet | Systolic Blood Pressure (mm Hg) | Baseline | 125.0 mm Hg | Standard Deviation 17 |
| Dietitian-Directed Diet Then Self-Directed Diet | Systolic Blood Pressure (mm Hg) | Period 1 (4-weeks) | 126.4 mm Hg | Standard Deviation 15.2 |
| Dietitian-Directed Diet Then Self-Directed Diet | Systolic Blood Pressure (mm Hg) | Period 2 (8-weeks) | 129.4 mm Hg | Standard Deviation 17.2 |
| Self-Directed Diet Then Dietitian-Directed Diet | Systolic Blood Pressure (mm Hg) | Baseline | 123.5 mm Hg | Standard Deviation 12.4 |
| Self-Directed Diet Then Dietitian-Directed Diet | Systolic Blood Pressure (mm Hg) | Period 1 (4-weeks) | 123.7 mm Hg | Standard Deviation 14.2 |
| Self-Directed Diet Then Dietitian-Directed Diet | Systolic Blood Pressure (mm Hg) | Period 2 (8-weeks) | 124.8 mm Hg | Standard Deviation 14.4 |