Body Mass Index and Initial Presentations of Cardiovascular Diseases

Stroke Clinical Trial

— CALIBER  

Official title:

Body Mass Index and Initial Presentations of Cardiovascular Diseases

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01704300
• Other study ID #: CALIBER 10_14
• Status: Completed
• Phase: N/A
• First received: October 8, 2012
• Last updated: October 10, 2012
• Start date: January 2001
• Est. completion date: March 2010

Study information

• Verified date: October 2012
• Source: University College, London
• Contact: n/a
• Is FDA regulated: No
• Health authority: United Kingdom: Research Ethics Committee
• Study type: Observational

Clinical Trial Summary

The association between obesity and cardiovascular disease (CVD) has mostly been studied using broad endpoints or have focused on cause-specific mortality. The investigators aim to compare the effect of body mass index (BMI) on different types of initial presentation of CVD.

Description:

Obesity has many detrimental effects on the cardiovascular system that can manifest in a range of clinical presentations. Many of these are mediated by frequently coexisting conditions such as diabetes, hypertension and dyslipidemia but there are also direct, progressive effects on the arteries and the heart muscle. As evident from autopsies, even from early adulthood the degree of coronary artery disease (CAD) correlates with the BMI and particularly the amount of abdominal fat. The multiple mechanisms by which obesity exerts its effects are still being elucidated.

Previous studies have assessed the effect of obesity on cause-specific mortality. Here the investigators analyze association of BMI with the first symptomatic presentation of cardiovascular disease across any phenotypes, to which the investigators refer to as "initial presentation" to distinguish from first presentation within a specific phenotype. For example, an initial presentation with myocardial infarction is an MI which is not preceded by stable angina, ischemic stroke or any other phenotype, rather than the first MI in a possible series of MIs, as is commonly used in other studies.

Adjustments The key risk factor of interest is baseline BMI, which the investigators define as the most recent measurement of BMI recorded up to 2 years prior to cohort entry date. BMI will be analyzed based on the following categories: underweight (<18.5 kg/m2), healthy (18.5 to 24 kg/m2), overweight (25 to 29 kg/m2), moderately obese (30 to 34 kg/m2), morbidly obese (>35 kg/m2). The healthy BMI category will be used as the reference in regression models.

Associations with BMI will be adjusted for age, sex, ethnicity, social deprivation, smoking, diabetes, and systolic blood pressure, total cholesterol (TCHOL) and high-density lipoprotein cholesterol (HDL). All baseline covariates will be obtained from within a 2 year window prior to study entry.

Statistical analyses Cause-specific Cox models will be used to measure the association between BMI categories and endpoints of interest. Multiple imputation will be used to replace missing values in prognostic factors. The investigators will estimate lifetime risk for each endpoint over time adjusting for competing risks.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 2240000
• Est. completion date: March 2010
• Est. primary completion date: March 2010
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Both
• Age group: 30 Years and older

Eligibility

Inclusion Criteria:

• Baseline age =30 years

Exclusion Criteria:

• prior atherosclerotic disease or stroke

Study Design

Observational Model: Cohort, Time Perspective: Retrospective

Related Conditions & MeSH terms

• Abdominal Aortic Aneurysm
• Acute Myocardial Infarction
• Angina
• Aortic Aneurysm
• Aortic Aneurysm, Abdominal
• Cardiovascular Diseases
• Heart Failure
• Infarction
• Myocardial Infarction
• Peripheral Arterial Disease
• Peripheral Vascular Diseases
• Stroke

Locations

Country	Name	City	State
United Kingdom	University College London	London

Sponsors (1)

Lead Sponsor	Collaborator
University College, London

Country where clinical trial is conducted

United Kingdom,