Subclinical Thyroid Dysfunction and Risk of Myocardial Infarction and Stroke

NCT ID: NCT00094237

Last Updated: 2017-04-25

Basic Information

• Recruitment Status: COMPLETED
• Total Enrollment: 3200 participants
• Study Classification: OBSERVATIONAL
• Study Start Date: 2004-09-30
• Study Completion Date: 2007-07-31

Brief Summary

To examine the association of subclinical hypothyroidism and risk of myocardial infarction and stroke in a large prospective cohort of post-menopausal women.

Detailed Description

BACKGROUND:

Cardiovascular disease, including myocardial infarction (MI) and stroke, is the leading cause of death for women in the United States. Subclinical hypothyroidism (SCH), in which thyroid hormone levels are in the normal range but thyroid stimulating hormone (TSH) is elevated, has been linked to abnormal lipid profiles, atherosclerosis, and MI. The literature is scant however, and the evidence constrained by small studies, many of cross-sectional design. Both the US Preventive Services Task Force and the Institute of Medicine recently concluded that current data are insufficient to inform clinical decision-making about the need for screening or treatment for SCH.

DESIGN NARRATIVE:

This is a case-cohort study within the 93,676-member Observational Study of the Women's Health Initiative, including 800 women who have experienced an MI, 750 with thrombotic/embolic stroke, and a randomly selected subcohort of 3,200 women density-matched for age, race/ethnicity, and clinical center. Participants have extensive baseline demographic, health, behavioral, and physical exam data and stored serum available. The investigators will measure TSH and thyroid hormone levels in order to identify SCH at entry. Follow-up includes annual health status updates and a physical exam in the third year; >=5 years have passed since enrollment for all women. Thus, using new laboratory studies and existing Women's Health Initiative (WHI) data, they will be able to answer these primary research questions: Among women without a history of thyroid disease, MI, or stroke: 1) Is subclinical hypothyroidism at baseline independently associated with risk of MI? 2) Is subclinical hypothyroidism at baseline independently associated with risk of ischemic stroke? 3) What form of association best describes the relationship between TSH, as a continuous measure, and risk of MI and stroke? 4) What are the population correlates (i.e., race/ethnicity, body mass index (BMI), hormone therapy, comorbidity) of SCH? This information - currently unavailable for middle-aged and older women - is germane to public health and health care policy to define the burden of illness associated with SCH, and to quantify the benefits and costs of eventual population screening and treatment

Conditions

Cardiovascular Diseases; Heart Diseases; Hypothyroidism; Myocardial Infarction; Cerebrovascular Accident

Study Design

• Observational Model Type: COHORT
• Study Time Perspective: PROSPECTIVE

Eligibility Criteria

Inclusion Criteria

No eligibility criteria

• Minimum Eligible Age: 50 Years
• Maximum Eligible Age: 79 Years
• Eligible Sex: FEMALE
• Accepts Healthy Volunteers: No

Sponsors

National Heart, Lung, and Blood Institute (NHLBI)

NIH

Sponsor Role: collaborator

University of North Carolina, Chapel Hill

OTHER

Sponsor Role: lead

Responsible Party

Responsibility Role: SPONSOR

Principal Investigators

Katherine Hartmann

Role: PRINCIPAL_INVESTIGATOR

University of North Carolina, Chapel Hill

Other Identifiers

R01HL076645

Identifier Type: NIH

Identifier Source: secondary_id

View Link

1274

Identifier Type: -

Identifier Source: org_study_id