Dietary Approaches to Stop Hypertension - Sodium Study (DASH-Sodium) - Catalog

Name

Dietary Approaches to Stop Hypertension - Sodium Study (DASH-Sodium)

Accession Number

HLB00280420a

Acronym

DASH-Sodium

Related studies

BSI Study IDs

DA2

Is public use dataset

False

Keywords

Has Study Datasets

True

Has Specimens

True

Specimen ID Type

Coded

Study Website

The Framingham Heart Study Group requires that the requestor must obtain full or expedited IRB/Ethics Committee review and approval to obtain these data. Waivers or a determination that the research is exempt from ethical regulations do not suffice.

False

Study type

Clinical Trial

Collection Type

Open BioLINCC Study

Cohort type

Adult

Interventions

Behavioral: diet, fat-restrictedBehavioral: diet, sodium-restricted

Study Open Date (Data)

2009-10-01

Study Open Date (Specimens)

2010-10-29

Date materials available

2008-10-13

Last updated

2005-10-17

Study period

1997-2002

Study Contacts
NHLBI Division

DCVS

Classification

Heart

HIV study classification

non-HIV

COVID study classification

non-COVID

Pre-Website # of Specimens Shipped

11521

# of Returned Specimens

0

Conditions

Cardiovascular Diseases
Heart Diseases
Hypertension
Vascular Diseases

Objectives

The primary objective of the DASH-Sodium Trial was to test the effects of two dietary patterns and three sodium intake levels on blood pressure in adult men and women with blood pressure higher than optimal or at stage 1 hypertension (systolic 120-159 mm Hg and diastolic 80-95 mm Hg).

Background

Blood pressure is an established risk factor for stroke and heart disease, and research has shown this risk to increase across the full range of blood pressure levels. The DASH study established that a diet emphasizing fruits, vegetables, whole grains, poultry, fish and low-fat dairy products can reduce systolic blood pressure by an average of 5.5 mm Hg and diastolic blood pressure by 3 mm Hg. Coupling the DASH diet with reduced sodium intake may potentially reduce blood pressure levels even further. Approximately 48% of adults have blood pressure above optimum levels, but below stage 2 hypertension (systolic blood pressure 120-159 mm Hg or diastolic pressure 80-95 mm Hg), and the DASH diet along with reduced sodium intake could provide suitable levels of control for a large segment of the population. To examine the effect of the DASH diet along with reduced sodium intake on blood pressure, two dietary patterns (a control diet typical of what many Americans consume and the DASH diet) were compared at three levels of sodium intake: (1) higher level comparable to current US intake, (2) an intermediate level which mirrors the upper limit of current recommendations, and (3) a lower intake which could lower blood pressure even more.

Subjects

Design

Four clinical centers and a coordinating center participated in the trial. Participants took part in a two week run-in period in which they were fed the higher sodium control diet. After the run-in period, participants were randomly assigned to one of the two diets using a parallel-group design and were fed each of the sodium levels for 30 consecutive days using a randomized crossover design. DASH - sodium was an outpatient feeding study, and study staff prepared all meals and snacks in research kitchens. To be eligible, participants had to be age 22 years or older, with diastolic blood pressure 80-95 mm Hg, systolic blood pressure 120-160 mm Hg, and free of anti-hypertensive medications or medications that would affect blood pressure. A total of 412 participants were randomized, and approximately 60% were African-American and 59% were women. Recruitment began in 1997 and all diets were completed in 1999.

Conclusions

Compared to the higher sodium control diet, the DASH diet reduced systolic blood pressure by an average of 5.9, 7.2, and 8.9 mm Hg for the higher, intermediate and lower sodium intakes respectively. Diastolic blood pressure was reduced by 2.9, 3.5, and 4.5 mm Hg for the higher, intermediate, and lower sodium intake levels. Reducing sodium intake in the control diet from higher to intermediate levels reduced systolic blood pressure by an average of 2.1 mm Hg and by 6.7 mm Hg to the lower sodium intake. Reducing sodium intakes to the lower level resulted in significantly lower systolic blood pressure in all sex, race, and hypertension status subgroups with the exception of non-black participants without hypertension. (N Engl J Med 2001;344:3-10).

Disease classification

Publications

Mat types

Plasma
Serum
Urine

The study population available in BioLINCC study data may be lower than total study enrollment due to Informed Consent restrictions and other factors.

  • Subjects

    Combination: 208

    Control: 204


    Last Modified: Feb. 8, 2024, 9:16 a.m.
  • Age

     

    COMBINATION

    CONTROL

    Total Subjects

    18-29

    6

    6

    12

    30-39

    34

    27

    61

    40-49

    86

    76

    162

    50-59

    58

    60

    118

    60-69

    19

    31

    50

    70-79

    5

    4

    9


    Last Modified: Feb. 8, 2024, 9:16 a.m.
  • Sex

     

    COMBINATION

    CONTROL

    Total Subjects

    Male

    85

    93

    178

    Female

    123

    111

    234


    Last Modified: Feb. 8, 2024, 9:16 a.m.
  • Race

     

    COMBINATION

    CONTROL

    Total Subjects

    Other

    3

    5

    8

    Black

    119

    115

    234

    White

    86

    84

    170


    Last Modified: Feb. 8, 2024, 9:16 a.m.

Please note that biospecimen availability is subject to review by the NHLBI, BioLINCC, and the NHLBI Biorepository. Certain biospecimens may not be made available for your request. Section 3 of the BioLINCC handbook describes the components of the review process

  • Material Types

    Serum, Plasma, Urine


    Last Modified: Feb. 8, 2024, 9:16 a.m.
  • General Freeze/Thaw Status

    As of 02/08/2024, the majority of plasma samples and nearly all serum and urine samples have undergone at least 1 freeze-thaw cycle.


    Last Modified: Feb. 8, 2024, 9:16 a.m.
  • Visits (Vials)

    02/08/2024
     

     

    Serum

    Plasma

    Urine

    Total Vials

    Screening Visit 3

    1,040

    1,640

    1,729

    4,409

    Intervention Phase 1

    780

    1,684

    1,829

    4,293

    Intervention Phase 2

    764

    1,508

    1,839

    4,111

    Intervention Phase 3

    744

    1,713

    1,837

    4,294

    Unknown

    .

    12

    .

    12


    Last Modified: Feb. 8, 2024, 9:16 a.m.
  • Visits (Subjects)

    02/08/2024
     

     

    Serum

    Total number of subjects

    Average volume (mL) per subject

    Screening Visit 3

    411

    0.93

    Intervention Phase 1

    367

    0.78

    Intervention Phase 2

    355

    0.79

    Intervention Phase 3

    352

    0.69

     

     

    Plasma

    Total number of subjects

    Average volume (mL) per subject

    Screening Visit 3

    409

    1.96

    Intervention Phase 1

    398

    1.94

    Intervention Phase 2

    387

    1.99

    Intervention Phase 3

    390

    2.62

    Unknown

    1

    5.85

     

     

    Urine

    Total number of subjects

    Average volume (mL) per subject

    Screening Visit 3

    377

    3.43

    Intervention Phase 1

    400

    2.96

    Intervention Phase 2

    385

    3.10

    Intervention Phase 3

    387

    3.06


    Last Modified: Feb. 8, 2024, 9:17 a.m.