The i3C Consortium is a collaborative effort among seven longitudinal cohorts across the world to examine the importance of childhood risk factors as predictors for subsequent clinical cardiovascular disease.

During the 1970s it became evident that the development of atherosclerosis, the major cause of heart attack and stroke, commenced in childhood. That this process was likely to be influenced by the same risk factors that predicted cardiovascular disease in adults was anticipated at that time. Over the following two decades, investigators in several countries initiated cohort studies to gain insights into these risk factors through childhood.


By 2002, the possibility of linking data collected in childhood to future cardiovascular disease (CVD) events was becoming a realistic focus in several of these cohorts. The idea of pooling data arose. Initially the Young Finns, CDAH, Bogalusa, and Muscatine studies were approached to participate in a collaborative effort. Through the increased power this collaboration would provide, the follow-up period to ascertain sufficient early cardiovascular disease events could be reduced. Detailed examination revealed that all four studies had gathered similar lifestyle and biological risk factors in childhood, among them – blood pressure, serum lipids, smoking and adiposity measures.

In 2008-2009 researchers associated with each cohort agreed to proceed with establishing a formal consortium ultimately named: the International Childhood Cardiovascular Cohort (i3C) Consortium.  As the capacity of the Consortium and the extent of its network developed, other similar studies were identified. These were the Princeton Lipid Research Clinics Study, three Minneapolis Childhood Cohort Studies, and the National Heart, Lung, and Blood Institute Growth and Health Study (NGHS).

Altogether more than 40,000 children were examined in the collaborating cohorts. Therefore, the i3C Consortium offers the potential to extend our knowledge about the childhood origin of adult cardiometabolic diseases and will focus on, but not be limited to, three key research areas: 1) Follow-up of CVD morbidity and mortality, 2) Genetic data collection and analyses, 3) Continued assessment of non-communicable disease outcomes (e.g., diabetes, cancer).

i3C Outcomes Study

The i3C Outcomes Study (funded by the National Heart, Lung, and Blood Institute (NHLBI) between 2014 and 2019) was the first longitudinal cohort study designed to locate large numbers of adults with detailed cardiovascular risk factors measurements obtained in childhood and a longitudinal harmonized data base. The Outcomes Study managed to contact ~ 20,000 participants from its seven cohorts. Among these individuals, over 700 adjudicated cases of CVD morbidity or mortality were observed. Therefore, the i3C Outcomes Study has significant potential for clarifying the relation between childhood levels of CV risk factors and development of adult CV disease, with an acknowledged public health goal of establishing evidence-based preventive guidelines that can be introduced during childhood.

i3C Consortium​

7 cohorts from 3 continents

More than 40,000 participants in childhood

Childhood age range 3-19 years

i3C Outcomes Study​

More than 20,000 participants contacted in adulthood

~ 700 adjudicated cases of CVD morbidity or mortality

Age range 40-68 years