The Haiti cardiovascular disease cohort: study protocol for a population-based longitudinal cohort

Jean Lookens, Olga Tymejczyk, Vanessa Rouzier, Caleigh Smith, Fabyola Preval, Inddy Joseph, Raynold Jean Baptiste, Joscar Victor, Patrice Severe, Sandra Apollon, Emelyne Dumont, Guyrlaine Forestal, Stephano St Preux, Vanessa Rivera, Grace Seo, Benedict Charles, Wilson Ariste, Justin Kingery, Jessy Devieux, Serena Koenig, Denis Nash, Daniel Fitzgerald, Monika Safford, Marie Marcelle Deschamps, Jean Pape, Margaret McNairy, Jean Lookens, Olga Tymejczyk, Vanessa Rouzier, Caleigh Smith, Fabyola Preval, Inddy Joseph, Raynold Jean Baptiste, Joscar Victor, Patrice Severe, Sandra Apollon, Emelyne Dumont, Guyrlaine Forestal, Stephano St Preux, Vanessa Rivera, Grace Seo, Benedict Charles, Wilson Ariste, Justin Kingery, Jessy Devieux, Serena Koenig, Denis Nash, Daniel Fitzgerald, Monika Safford, Marie Marcelle Deschamps, Jean Pape, Margaret McNairy

Abstract

Background: Cardiovascular disease (CVD) is the leading cause of mortality among Haitians, having surpassed HIV in the last decade. Understanding the natural history of CVD in Haitians, including the age of onset, prevalence, incidence, and role of major risk factors and social determinants, is urgently needed to develop prevention and treatment interventions. Aim 1: Establish a population-based cohort of 3000 adults from Port-au-Prince and assess the prevalence of CVD risk factors and diseases and their association with social and environmental determinants. Aim 2: Determine the incidence of CVD risk factors and CVD during 2-3.5 years of follow-up and their association with social and environmental determinants.

Methods: The Haiti CVD Cohort is a longitudinal observational study of 3000 adults > 18 years in Port-au-Prince (PAP), Haiti. The study population is recruited using multistage random sampling from census blocks. Adults receive blood pressure (BP) measurements in the community and those with elevated BP are referred to the Groupe Haitien d'Etude Sarcome de Kaposi et des Infections Opportunistes Clinic for care. After informed consent, participants undergo a clinical exam with medical history. BP, electrocardiogram, echocardiogram, a study questionnaire on health behaviors, and laboratory specimens. Every 6 months, BP is remeasured. At 12 and 24 months, clinical exams and questionnaires are repeated. Labs are repeated at 24 months. Adjudicated study outcomes include the prevalence and incidence of CVD risk factors (hypertension, diabetes, obesity, dyslipidemia, kidney disease, inflammation, poor diet, smoking, and physical inactivity) and events (myocardial infarction, heart failure, stroke, and CVD mortality). We also measure social determinants including poverty. Depression, stress, social isolation, food insecurity, and lead exposure. Blood, urine, and stool samples are biobanked at study enrollment.

Discussion: The Haiti CVD Cohort is the largest population-based cohort study evaluating CVD risk factors and CVD among adults in urban Haiti with the goal of understanding the drivers of the CVD epidemic in Haiti. Study outcomes are comparable with existing international cohorts, and the biobank will provide important data for future research. Our goal is to translate findings from this study into pragmatic prevention and treatment interventions to fight the CVD epidemic in Haiti.

Keywords: Cardiovascular medicine; Epidemiology; Hypertension; Public health.

Conflict of interest statement

The authors declare that they have no competing interests.

Figures

Fig. 1
Fig. 1
Adapted Social Ecological Model of CVD in Haiti
Fig. 2
Fig. 2
Initial Funding Period Timeline Overview
Fig. 3
Fig. 3
Map of Study Recruitment Area in Metropolitan Port au Prince and Research Site at GHESKIO

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