Bogalusa Heart Study

To determine the natural history of atherosclerosis, coronary artery disease, and hypertension in children and adults from birth through mid-life in a total biracial community.

BACKGROUND:

The Bogalusa Heart Study has been a long-term epidemiologic study. The investigators have identified and followed black and white participants for nearly 40 years, and have described the incidence and prevalence of biologic and behavioral cardiovascular disease risk factors from childhood through adulthood. Their participation has enabled the study to not only document differences between males and females, but also between blacks and whites. The results from the Bogalusa Heart Study have clearly documented that the genesis of atherosclerosis has its basis in childhood, and that prevention can and must begin at the early ages.

The Bogalusa Heart Study had been funded over the years by the Specialized Centers of Research (SCOR) Program. The SCOR program was initiated by NHLBI in 1970 to expedite the development and application of new knowledge essential for improved diagnosis, treatment, and prevention of arteriosclerosis, hypertension, pulmonary disease, and thrombosis. In 1984 a Demonstration and Education Component was added to the parent SCOR of the Bogalusa Heart Study in order to translate the experience gained in epidemiological studies into an intervention study designed to retard the development of cardiovascular risk factors in children. Beginning in 1987, the Bogalusa Heart Study was supported by a regular research grant. Beginning in 1997, the study is supported by the cooperative agreement mechanism.

DESIGN :

The initial survey in 1973-1974 was restricted to children ages 2 1/2 to 14. A physical examination was conducted and information was collected on anthropometric data, hemoglobin, blood pressure, serum lipids, and health history. Over 3,500 children participated. The second cross-sectional survey of 1976-1977 and subsequent surveys expanded the eligible population to include all children ages 5-17 years. The second survey of over 4,000 children also included information on salt intake, smoking, health beliefs, and attitudes, and for girls ages 8-17, menstrual history and oral contraceptive use. The third survey of over 3,500 participants in 1978-1979 also collected anthropometric measurements on skinfold thickness and two measurements of heart rate. The fourth survey of over 3,300 participants in 1981-1982 added data on alcohol use, Type A behavior, peer networks and dieting habits.

The Bogalusa Heart Study continued to use a cross-sectional and longitudinal design with the general cross-sectional survey of approximately 3,700 Bogalusa children ages five to seventeen in 1988-1989 in the sixth screen and additional longitudinal studies to recall children in defined subgroups for more intensive evaluation. Half of the 12,000 participants screened since 1973 had been studied three or more times. There were several other cohort groups and studies. The Newborn-Infant Cohort Study was designed to describe distributions, inter-relationships, and trends through time for blood pressure, serum lipid and lipoprotein concentrations, dietary intake patterns, and anthropometric measurements. Four hundred and forty infants born between January 1, 1974 through June 30, 1975 were examined at birth, at six months, and yearly at ages one through four and at seven, ten and thirteen years for cardiovascular risk factor variables. The Post High School Study examined young adults ages 21 through 30 who previously were examined as children ages five through fourteen in the first Bogalusa Heart Study screening in 1973-1974. The population included approximately 4,603 young adults originally screened and any other children or adolescents examined for the first time in any subsequent surveys.

The fifth screening began in 1988 and extended through December 1991. The Pediatric Pathology Risk Factor Program, which began in 1978, documented the relationship of cardiovascular disease risk factors to anatomic and pathologic changes. A local information system was established to obtain family or coroner's consent to autopsy any deceased resident between the ages of three and 26 in the Bogalusa area. Autopsy specimens were collected from over 100 deceased children and young adults, of whom approximately forty percent had been previously examined in the Bogalusa Heart Study.

Major activity during 1988-1991 involved 24-hour dietary recall collections on all the 1963, 1966, and 1968 birth cohorts attending the Post High School Study. A food frequency questionnaire was also self-administered to all the Post High School Study participants. The use of these two dietary methodologies, 24-hour dietary recall and food frequency questionnaire, provided data to assess the nutrient composition of diets of young adults, assess the weekly consumption of individual foods, compare nutrient composition data with food frequency data, and compare dietary intakes at the post high school age with those of school age. Several substudies were conducted using the Bogalusa Heart Study population. Among them were the impact of childhood obesity on risk factors, the relationship of apolipoproteins A-I and B in children to parental myocardial infarction and the relationship between left ventricular size as demonstrated by echocardiography and blood pressure distribution.

The study was renewed in Fiscal Year 1992 in order to follow-up the previously examined young adults for development of abnormal levels of cardiovascular risk factors and even clinical disease.

In 1997, the study was renewed and extended through 2002, and from 2002-2010, and again in 2012 in order to study the impact of genetic factors on the evolution from childhood cardiovascular risk factors to subclinical and clinical morbidity in an adult population, ages 20 to 43, who had been followed over a long period of time. The study also seeks to study the association of risk factor phenotypes to anatomic changes in the cardiovascular system as seen by necropsy. The population for genotype-phenotype studies includes approximately 1,400 siblings derived from longitudinal birth cohorts.

The cardiovascular phenotypes include obesity, blood pressure, lipids, lipoproteins, apoproteins, homocysteine, glucose-insulin, fibrinogen, plasminogen activator inhibitor-1 and von Willebrand Factor. Environmental risk factors consist of sociodemographic characteristics, tobacco and alcohol use, oral contraception, physical activity, cognitive and physical function, and quality of sleep and diet. Subclinical morbidity includes echo-Doppler measurements of cardiac-carotid structure and function. Using robust sibling pair linkage methods, a genome-wide search involving 391 markers with spacing of 10 centimorgans is conducted for genes which influence quantitative traits. This is supplemented with 41 highly polymorphic markers located in or near candidate genes likely to be related to obesity, lipoprotein metabolism, blood pressure, insulin resistance, diabetes, atherogenesis and thrombosis.

Approximately 75 percent of the dollars of a Specialized Center of Research (SCOR) in Arteriosclerosis (P50HL14103) were used to support the Bogalusa Heart Study from 1972 through 1986.

Since 2002, the study has been supported by the National Institute on Aging (NIA), the National Heart, Lung, and Blood Institute (NHLBI), the National Institute of Environmental Health Sciences (NIEHS), and the National Institute of Child Health and Human Development (NICHD).

Eligibility Criteria:
Index individuals were identified as those living in Bogalusa, Louisiana between 1972 and 2000 who attended Bogalusa City Schools in childhood. The families of index individuals were eligible to participate in certain sub-studies e.g. sibling and parent studies. After 2000, only previously examined individuals and, in limited circumstances, their offspring, were eligible for participation in on-going follow-up of heart disease risk factors and related outcomes.