China Kadoorie Biobank (CKB)

Chronic diseases, such as stroke, heart disease, diabetes and cancer, are the leading causes of disability and death worldwide. Understanding what causes these diseases in different populations can lead to improvements in disease prevention, risk prediction and development of new treatments. One way of identifying causes of disease is through blood-based “prospective cohort” studies, in which large numbers of apparently healthy individuals from the general population are interviewed and measured, and have blood collected and stored for future tests of genetic and non-genetic biomarkers. The health status of the study participants is then monitored “prospectively” to see who develops what disease. When sufficiently large numbers of people have developed a particular disease (“cases”), their blood and other characteristics are compared with those from “controls” who have not developed the disease. We have established one of the world’s largest studies of this kind, involving 512,000 adults in China during 2004-08. After 10-year follow-up, large numbers of disease outcomes have been accumulated, which, together with other lifestyle, environment, genetic and blood biomarker data, will enable scientists to make important discoveries about genetic and non-genetic causes of many diseases. The study findings will help improve disease prevention, prediction and treatment, benefiting populations worldwide.

Despite recent advances, our ability to prevent and treat many non-communicable chronic diseases (eg, stroke, heart disease, diabetes, cancer) is still limited. Understanding what causes these diseases in diverse populations can lead to improvements in risk prediction, treatment and disease prevention, and the development of “precision” medicines. CKB is a blood-based prospective cohort study of >512,000 adults, recruited from 10 diverse areas across China (during 2004-08), with extensive data collection at baseline and subsequent resurveys and long-term storage of biological samples. By 1.1.2017, ~45,000 deaths and ~1M coded episodes of hospitalisation of ~1500 major disease types have been recorded. These exposure and outcome data are complemented by cohort-wide genotyping (currently for 102,000 participants), large-scale whole genome sequencing, and conventional and multi-omics assays for nested case-control studies of specific diseases.
Over the next 5 years, the CKB will continue to develop, maintain, and share the resource through: (i) continued follow-up for disease events through linkage to mortality/morbidity registries and health insurance systems; (ii) ascertainment, adjudication and sub-phenotyping of major disease outcomes (e.g. stroke, IHD, cancer); (iii) resurvey of ~25,000 survivors with additional enhancements (e.g. accelerometers) and new sample collection (e.g. faecal/saliva samples); (iv) maintenance, enhancement and development of IT systems underpinning the infrastructure and coordination of the study; (v) processing, managing and sharing large and complex data with the wider research community; (vi) secure bio-repositories with DNA extraction and sample reformatting.
Based on the data collected or to be generated, a wide range of research will be undertaken, both for hypothesis testing and generating. These will include (i) prospective analyses of major risk factors with major diseases and their subtypes; (ii) Genome-wide association studies of traits, lifestyle factors and diseases; (iii) Mendelian randomisation studies of causal relevance of traits for major diseases; (iv) Phenome-wide association studies of functional variants to aid drug development; (v) Comprehensive assessment of the health effects of environmental exposures (eg, ambient and household air pollution, ambient temperature, and built environment) on major CVD and non-CVD. The research priority will be given to those that are considered to be novel and to have major public health impact.
CKB is a global resource with huge potential to improve our understanding of disease aetiology, risk prediction and development of new therapies. It will also complement other large prospective studies (eg, UK Biobank) enabling investigations into a different range of genetic and other exposures that may be rare or absent in Western populations.