Blood High Pressure
Conditions
Keywords
dietary patterns, blood pressure, adolescents, dietary sodium
Brief summary
The Camp DASH study trial will compare the effect of two dietary patterns and two levels of sodium intake on blood pressure and blood lipids in adolescents in the upper third of distribution for blood pressure. The two dietary patterns are based on the Dietary Approaches to Stop Hypertension (DASH) trial in adults.
Detailed description
The Camp DASH study is a controlled trial. the aim of which is to compare the effect of two dietary patterns and two levels of sodium intake on blood pressure and blood lipids in adolescents in the upper third of distribution for blood pressure. The study also assesses whether influences on blood pressure and blood lipids of dietary interventions vary according to sex, race/ethnic groups, baseline levels, and other personal characteristics. The proposed dietary interventions of DASH dietary patterns and sodium reduction have been shown to be effective in lowering blood pressure in adults. The two dietary patterns are based on the Dietary Approaches to Stop Hypertension (DASH) trial in adults. They are a Usual diet typical of what many American adolescents eat, and a DASH-type diet. The DASH diet is rich in fruits, vegetables, and low-fat dairy foods and low in saturated fat and total fat compared to the Usual diet. The two sodium levels are High reflecting current US consumption and Low reflecting current recommended intake levels. Weight will be held constant by adjusting energy intake. The study participants will live in a residence hall on the Purdue campus where all food and beverages will be provided, and meals and snacks will be supervised.
Interventions
OTHERDASH diet
DASH style diet rich in fruits, vegetables, and low-fat dairy foods and low in saturated fat and total fat
OTHERLow Na diet
Sodium intake of 1500 mg/d (65 mmol, or 0.75 mg/Kcal/d), representing the Adequate Intake recommended by the Institute of Medicine.
OTHERHigh Na diet
Sodium intake of 3500 mg/d (152 mmol, or 1.73 mg/Kcal/d, representing the highest sodium intake used for adults in the DASH Sodium trial.
OTHERUsual Diet
The usual diet will include foods that provide the majority of energy for adolescents in the U.S., i.e. grain based desserts, pizza, sugary drinks,pasta, chicken, and chicken mixed dishes.
Sponsors
Centers for Disease Control and Prevention
Johns Hopkins University
Indiana University School of Medicine
University of California, San Diego
National Heart, Lung, and Blood Institute (NHLBI)
Purdue University
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
PREVENTION
Masking
SINGLE (Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
11 Years to 15 Years
Healthy volunteers
Yes
Inclusion criteria
* White, black, Hispanic, and Asian * SBP in the upper one-third of the distribution for their given sex, age, and height
Exclusion criteria
* Pre-existing lipid disorders, abnormal liver or kidney function * Taking medications that alter mineral absorption or metabolism, affect blood pressure or lipids * If subjects are taking dietary supplements and refuse to discontinue them 2 months prior to the study. * Taking non-prescription illegal drugs, smoke, or drink alcohol * Pregnancy * Carry an epi pen for food-related allergies
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Mean systolic blood pressure (SBP) | End of 25 day feeding intervention | The primary outcome is mean SBP at the end of each intervention feeding period. Mean end of intervention SBP is the average of daily readings during days 19-25 of each intervention feeding period. Blood pressure will also be measured periodically at baseline and throughout the study. |
| Non-HDL Cholesterol (HDLC) | End of 25 day feeding intervention | Fasting blood samples for lipids and other variables will be drawn at the beginning and end of each feeding period |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| HDL-cholesterol | End of 25 day feeding intervention | Fasting blood samples for lipids and other variables will be drawn at the beginning and end of each feeding period |
| LDL-cholesterol | End of 25 day feeding intervention | Fasting blood samples for lipids and other variables will be drawn at the beginning and end of each feeding period |
| Cholesterol:HDLC ratio | End of 25 day feeding intervention | Fasting blood samples for lipids and other variables will be drawn at the beginning and end of each feeding period. |
| Triglycerides | End of 25 day feeding intervention | Fasting blood samples for lipids and other variables will be drawn at the beginning and end of each feeding period |
| Diastolic blood pressure (DBP) | End of 25 day feeding intervention | The secondary outcome is mean DBP at the end of each intervention feeding period. Mean end of intervention DBP is the average of daily readings during days 19-25 of each intervention feeding period. Blood pressure will also be measured periodically at baseline and throughout the study.. |
| Regulators of sodium metabolism | End of 25 day feeding intervention | Regulators of sodium homeostasis (renin, aldosterone, angiotensin) will be measured at the beginning and end of the feeding period |
| Augmentation index | End of 25 day feeding intervention | Pulse wave analysis (At Cor Medical) will be used to measure changes in augmentation index (AI) with intervention to index central blood pressure. |
| Vasoreactivity | End of 25 day feeding intervention | Skin flow motion (laser-doppler flowmetry) to measure diet-induced changes in vaso-reactivity will provide mechanistic information on microvascular control. |
| Urinary mineral excretion | End of 25 day feeding intervention | Two 24-hr urine samples at the end of the feeding periods will be analyzed for sodium, potassium, magnesium, and calcium.. |
| Total cholesterol | End of 25 day feeding intervention | Fasting blood samples for lipids and other variables will be drawn at the beginning and end of each feeding period. |
Countries
United States
Outcome results
None listed