Dietary Patterns and Risk of Cardiovascular Disease

Sponsor
Harvard School of Public Health (HSPH) (Other)
Overall Status
Completed
CT.gov ID
NCT00005514
Collaborator
National Heart, Lung, and Blood Institute (NHLBI) (NIH)
120,000
125

Study Details

Study Description

Brief Summary

To study, prospectively, the association between dietary patterns and risk of coronary heart disease (CHD), ischemic stroke, and hemorrhagic stroke in cohort studies of 121,700 women age 30 to 55 years at baseline in 1976 (the Nurses; Health Study; NHS) and 51,529 men aged 40-75 years at baseline in 1986 (the Health Professionals Follow-up Study; HPFS).

Detailed Description

DESIGN NARRATIVE:

In the first five years of the study analyses were performed on food consumption data collected through semiquantitative food frequency questionnaires at baseline and during follow-up in the Nurses Health Study and Health Professionals Follow-up Study cohorts. Dietary patterns were derived from the food consumption data using factor analysis, cluster analysis, and dietary indexes (based on prevailing dietary recommendations). In addition, using existing datasets from dietary validation studies in sub-samples of the two cohorts, the reproducibility and validity of dietary patterns defined by factor/cluster analysis and dietary indexes were evaluated. Further, using prospectively collected and stored bloods in the NHS (n-32,826) during 1989-1990 and the HPFS (n-18,000) during 1993-1994, the investigators examined whether observed associations between dietary patterns and CHD were explained by (or mediated through) plasma biochemical measurements (including serum lipids, thrombotic factors, antioxidants, fasting insulin, and homocysteine levels) in a nested case-control design; and they assessed prospectively the relationship between dietary patterns and these biomarkers in the control samples.

The study was renewed in 2005 to apply novel statistical methods (such as confirmatory factor analysis and structural equation modeling) to validate various dietary patterns and examine their associations with risk of type 2 diabetes, cardiovascular disease and total mortality in two large ongoing cohort studies, the Nurses' Health Study (n=121,700) and Health Professionals' Follow-up Study (n=51,529). In addition to evaluating prevailing dietary recommendations, the study will also examine the role of the Mediterranean-type dietary pattern, the Dietary Approaches to Stop Hypertension (DASH) dietary pattern, and the Atkins-type diet in predicting health outcomes. Using repeated measurements of diet, the study will examine the impact of changes in eating patterns and diet quality over time on subsequent risk of diabetes, CVD, and total mortality. In addition, it will examine relationships between major dietary patterns and novel plasma biomarkers of inflammation and endothelial function and whether such relationships are mediated through obesity. Finally, the study will test interactions between dietary patterns and individual single nucleotide polymorphisms (SNPs) and haplotypes of several promising candidate genes in the inflammation and endothelial dysfunction pathway on risk of coronary heart disease, including PPARa, PPARy, Adiponectin (AdipoQ), PON1, IL-6, TNF-a, ICAM-1, VCAM-1, E-Selectin, NOS3, ACE gene, and angiotensinogen (ANG) genes.

Study Design

Study Type:
Observational
Actual Enrollment :
120000 participants
Observational Model:
Cohort
Time Perspective:
Prospective
Study Start Date :
Aug 1, 1998
Actual Primary Completion Date :
Jan 1, 2009
Actual Study Completion Date :
Jan 1, 2009

Outcome Measures

Primary Outcome Measures

  1. Incident cardiovascular disease [1980-2008]

    Myocardial infarction, fatal coronary disease, and stroke documented by medical records

Eligibility Criteria

Criteria

Ages Eligible for Study:
N/A and Older
Sexes Eligible for Study:
All
Accepts Healthy Volunteers:
No

no history of chronic diseases at baseline

Contacts and Locations

Locations

No locations specified.

Sponsors and Collaborators

  • Harvard School of Public Health (HSPH)
  • National Heart, Lung, and Blood Institute (NHLBI)

Investigators

None specified.

Study Documents (Full-Text)

None provided.

More Information

Publications

Responsible Party:
Frank B. Hu, Professor, Harvard School of Public Health (HSPH)
ClinicalTrials.gov Identifier:
NCT00005514
Other Study ID Numbers:
  • 5032
  • R01HL060712
First Posted:
May 26, 2000
Last Update Posted:
Mar 20, 2013
Last Verified:
Mar 1, 2013

Study Results

No Results Posted as of Mar 20, 2013