Chocolate and CVD Risk in Postmenopausal Women

Study Overview
=================
Brief Summary
-----------------
The investigators will conduct an epidemiological analysis of data from the Women's Health Initiative to investigate the prospective association between chocolate intake and the risk of heart disease and stroke.

Detailed Description
-----------------
BACKGROUND: Three recent meta-analyses found significant prospective inverse associations between chocolate intake and cardiovascular disease risk. Evidence from these meta-analyses suggests that such inverse associations may only apply to elderly individuals or those with preexisting major chronic disease. OBJECTIVE: The investigators will assess the association between habitual chocolate intake and subsequent incident coronary heart disease (CHD) and stroke, and the potential effect of modification by age. DESIGN: The investigators will conduct multivariable Cox regression analyses using data from 83,310 postmenopausal women free of baseline preexisting major chronic disease in the prospective Women's Health Initiative cohort. Chocolate intake was assessed using a food frequency questionnaire. Physician adjudicated events or deaths were ascertained up to September 30, 2013.

Official Title
-----------------
Chocolate Intake and Heart Disease and Stroke in the Women's Health Initiative: a Prospective Analysis

Conditions
-----------------
Cardiovascular Disease, Heart Disease, Stroke

Intervention / Treatment
-----------------
* Behavioral: chocolate consumption level
* Other: physician diagnosis of first occurrence of serious chronic disease


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Postmenopausal women age between 50 and 79 years enrolled in the Women's Health Initiative (WHI) Observational Study, or in the control arm of one or more overlapping WHI clinical trials. Exclusion Criteria: implausible energy intakes, defined as <600 kcal/d or >5,000 kcal/d; implausible body mass indices (BMI) (<15 or >50 kg/m2) implausible height<122 cm (4 ft.) self-reported preexisting serious chronic disease at baseline, including diabetes, angina, myocardial infarction (MI), stroke, heart failure, coronary artery bypass graft, percutaneous coronary intervention or cancer. missing data on preexisting major chronic disease or any exposure, outcome or confounder variables.

Ages Eligible for Study
-----------------
Minimum Age: 55 Years
Maximum Age: 79 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| chocolate consumption level referent<br>women who ate 1 oz. (28.35 g) of chocolate <1 time/month | Behavioral: chocolate consumption level<br>* level of consumption of 1 oz. of chocolate, as assessed at baseline<br>|
| chocolate consumption level 2<br>women who ate 1 oz. (28.35 g) of chocolate between 1 and <1.5 times/month | Behavioral: chocolate consumption level<br>* level of consumption of 1 oz. of chocolate, as assessed at baseline<br>|
| chocolate consumption level 3<br>women who ate 1 oz. (28.35 g) of chocolate between 1.5 and <3.5 times/month, | Behavioral: chocolate consumption level<br>* level of consumption of 1 oz. of chocolate, as assessed at baseline<br>|
| chocolate consumption level 4<br>women who ate 1 oz. (28.35 g) of chocolate between 3.5 times/month and <3 times/week | Behavioral: chocolate consumption level<br>* level of consumption of 1 oz. of chocolate, as assessed at baseline<br>|
| chocolate consumption level 5<br>women who ate 1 oz. (28.35 g) of chocolate >3 times/week | Behavioral: chocolate consumption level<br>* level of consumption of 1 oz. of chocolate, as assessed at baseline<br>|
| No physician diagnosis<br>No incidence of serious chronic disease prior to visit 3 | Other: physician diagnosis of first occurrence of serious chronic disease<br> <br> |
| Physician diagnosis<br>Incidence of serious chronic disease prior to visit 3 | Other: physician diagnosis of first occurrence of serious chronic disease<br> <br> |
| Younger<br>Age<65 years at follow-up baseline | Behavioral: chocolate consumption level<br>* level of consumption of 1 oz. of chocolate, as assessed at baseline<br>|
| Older<br>Age>=65 years at follow-up baseline | Behavioral: chocolate consumption level<br>* level of consumption of 1 oz. of chocolate, as assessed at baseline<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| incidence of heart disease | physician adjudicated first occurrence of, or death due to, heart disease | between the baseline survey (1993-8) & September 30, 2013, average 13.4 years | 
| incidence of stroke | physician adjudicated first occurrence of, or death due to, stroke | between the baseline survey (1993-8) & September 30, 2013, average 13.4 years | 
| incidence of heart disease or stroke | physician adjudicated first occurrence of, or death due to, heart disease or stroke | between the baseline survey (1993-8) & September 30, 2013, average 13.4 years | 
| change in chocolate intake | change in chocolate intake between visit 1 and 3 | time between the baseline and visit 3, average 3 years | 
| change in dietary energy intake | change in dietary energy intake between visit 1 and 3 | time between the baseline and year 3, average 3 years | 
| change in dietary fat intake | change in dietary fat intake between visit 1 and 3 | time between the baseline and year 3, average 3 years | 
| change in BMI | change in BMI between visit 1 and 3 | time between the baseline and year 3, average 3 years | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Coronary heart disease, stroke, chocolate consumption, postmenopausal women, nutrition, dietary intake, epidemiology