An observational study in Dietary Modification and Blood Pressure, sponsored by Johns Hopkins Bloomberg School of Public Health. Completed. Open to participants aged 22 Years to 100 Years. Per ClinicalTrials.gov, last updated 2018-01-18.
Sponsored by Johns Hopkins Bloomberg School of Public Health · Observational
The present record represents a secondary data analysis of the Dietary Approaches to Stop Hypertension (DASH) trial. Study data and specimens were accessed through the National Heart, Lung, and Blood Institute (NHLBI) Biologic Specimen and Data Repository Coordinating Center (BioLINCC). A global, untargeted, metabolomic profile was used to investigate biomarkers of the DASH dietary pattern as well as blood pressure change.
The present study was conducted in order to: 1) quantify the metabolomic expression of the DASH dietary pattern; and 2) examine the relationship between metabolites that reflect the DASH dietary pattern and blood pressure change. This secondary data analysis leverages the completed DASH trial, a randomized feeding trial (N=459).
The study population consisted of men and women (aged 22 years and older) with systolic blood pressure \<160 mmHg and diastolic blood pressure 80-95 mmHg who were not taking antihypertensive medication. The mean age was 44 years, about half were women, and approximately 2/3 were black or another race/ethnicity minority. The mean body mass index was 28 kg/m2 and mean blood pressure was 132/82 mmHg.
Exclusion Criteria:
The DASH diet consisted of a high intake of fruits, vegetables, and low-fat dairy products. It included a wide range of sources of protein, such as meat, fish, poultry, nuts, and beans. Sugar-sweetened beverages, desserts, and red meat were restricted. In terms of nutrients, the DASH diet had a high amount of fiber and protein; low amounts of saturated fat, total fat, and cholesterol; and intake of potassium, magnesium, and calcium at levels close to the 75th percentile of U.S. consumption.
Behavioral: DASH diet
Potassium and magnesium intake was similar to the 75th percentile of U.S. consumption. Fiber intake was high. The fruits and vegetables diet consisted of more fruits and vegetables and fewer snacks and desserts than the control diet, but otherwise was similar to the control diet.
Behavioral: Fruits and vegetables diet
For the control diet, macronutrient intake was similar to average U.S. consumption and intake of potassium, magnesium, and calcium were similar to the 25th percentile of U.S. consumption. Sodium intake was approximately 3 g/day in each diet.
Behavioral: Control diet
Diet intervention
Diet intervention
Diet intervention
Serum metabolites
Metabolites were measured using a global, untargeted, metabolomic platform in serum specimens collected at the end of the 8 week diet intervention in the DASH trial. Reverse phase, untargeted ultrahigh-performance liquid chromatography tandem mass spectrometry quantification was used to measure metabolites. Peaks were quantified by calculating the area under the curve. Data were normalized to account for day-to-day instrumental variation. Compounds were identified by comparison to a library of purified standards or recurrent unknown entities and matches were determined based on retention time, mass-to-charge ratio, and chromatographic data. A relative measure of each metabolite (not absolute) is determined. The Metabolon (Durham, NC) platform quantifies over 1,000 compounds representing a broad range of metabolic compounds, including amino acids, carbohydrates, cofactors and vitamins, energy, lipids, nucleotides, peptides, and xenobiotics (chemicals, drugs, and food components).
Time frame: 8 week follow-up visit
Blood pressure
The change in blood pressure was defined as the blood pressure level at the end of the 8 week diet intervention minus the blood pressure level at baseline.
Time frame: 8 week follow-up visit
No study locations are listed for this record.
Plan to share: No
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Johns Hopkins Bloomberg School of Public Health