What is the goal of the CARDIA study?
The Coronary Artery Risk Development in Young Adults (CARDIA) study aims to identify factors that begin in young adulthood, which is two to three decades before the onset of cardiovascular disease in later life. The CARDIA study is designed to examine the factors that contribute to the development of cardiovascular disease, as well as to better understand the natural history of cardiovascular disease over the entire adult life.
- CARDIA is a long-term study of cardiovascular disease beginning in young adulthood.
- The study includes over 5,000 black and white adults who were aged 18 to 30 years in 1985 to 1986.
- CARDIA is one of the longest running studies of its kind, monitoring participants for over 30 years.
- The study has helped understand the importance of early adulthood factors that increase the risk of cardiovascular disease later in life.
What are the key findings of the CARDIA study?
Long-term studies like the CARDIA study are critical to our ability to shine a light on the root causes of cardiovascular disease beginning early in life. Over the last 30 years, findings from the CARDIA study have contributed substantially to our knowledge about the importance of lifestyle and environmental factors in the development of cardiovascular disease later in life.
The following are some findings from CARDIA data:
- Having above optimal levels of risk factors for heart disease between the ages of 18 and 30 can mean a two to three times greater risk of later developing atherosclerosis, a strong predictor of future heart disease.
- Young adults who maintain their weight over time, even if they are overweight, have lower risk factor levels for heart disease and are less likely to develop metabolic syndrome in middle age than those whose weight increases.
- Young adults who frequently eat fast food gain more weight and have a greater increase in insulin resistance in early middle age. After age 15, those who ate fast food more than twice each week compared to less than once a week had gained an extra ten pounds and had a two-fold greater increase in insulin resistance, a risk factor for type 2 diabetes.
- Living in racially segregated neighborhoods is associated with higher blood pressure among black adults, while moving away from segregated areas is associated with a decrease in blood pressure.
The NHLBI continues to leverage CARDIA data and stored biological specimens to uncover more findings. The NHLBI welcomes researchers to utilize the valuable resources that have been collected since the study began in 1983. Learn more about utilizing CARDIA resources through the study website and through NHLBI’s biospecimen and data repository, BioLINCC.
How was the CARDIA study conducted?
The CARDIA study was initially funded in 1983 for a five-year cycle that included two clinical exams. The study began with a group of 5,115 black and white men and women aged 18 to 30 years in 1985-86. The participants were selected so that there would be approximately the same number of people in subgroups of race, gender, education (high school or less and more than high school), and age (18 to 24 and 25 to 30) in each of four centers: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California.
Study renewals have allowed for additional follow-up clinical exams. Only original CARDIA participants could participate in the follow-up exams after completing their initial exam at the start of the study.
While the aims of each follow-up exam have varied, data have been collected on a variety of factors believed to be related to heart disease in later life. These include conditions with clear links to heart disease, such as blood pressure, cholesterol and other lipids, and blood glucose levels. Data have also been collected on physical measurements such as weight and skinfold fat, as well as lifestyle factors such as substance use (tobacco and alcohol), eating and exercise patterns, behavioral and psychological variables, medical and family history, and other chemistries (e.g., insulin). In addition, echocardiography was performed during years 5, 10, 25, and 30; cardiac computed tomography during years 15, 20, and 25; carotid ultrasound during year 20; measures of cognitive function at years 25 and 30; and a brain magnetic resonance image (MRI) in a subset of participants at years 25 and 30.
The NHLBI Large-Scale DNA Sequencing Project provided an opportunity for researchers to scour thousands of DNA sequences in extremely fine detail, including genomic information from the CARDIA study. The goal of the project was to discover specific genetic variants that map precisely with disease phenotypes.