UK Biobank Imaging Enhancement Main phase

The challenges of understanding the determinants of common life-threatening and disabling diseases are substantial. Such conditions are typically caused by many different exposures that each have moderate effects and interact with each other in complex ways. Prospective cohorts, such as UK Biobank, have advantages for the comprehensive and reliable quantification of the combined effects of different types of risk factor on health outcomes. In particular, exposures can be assessed before they are affected by disease or its management, and diseases can be assessed that are not readily investigated by retrospective studies (e.g. dementia). Moreover, all of the beneficial and adverse effects of a specific factor on the life-time risks of different diseases can be considered. Prospective studies do, however, need to involve large numbers of participants because only a relatively small proportion will develop any particular condition. UK Biobank has involved the collection of extensive baseline questionnaire data, physical measurements and biological samples from 500,000 men and women aged 40-69 at baseline, and their health is now being followed long-term. This proposal is for enhanced phenotyping of 100,000 of the participants with a set of imaging modalities that have been carefully chosen to provide considerable additional information that is likely to be relevant to many different health outcomes.

UK Biobank has involved the collection of extensive baseline questionnaire data, physical measurements and biological samples from 500,000 men and women aged 40-69 at baseline in 2006-10, and their health is now being followed by linkage to health records and by web-based questionnaires. This proposal involves the enhancement of the phenotyping of 100,000 participants in UK Biobank with information from multiple imaging modalities involving the brain, heart, large blood vessels, body composition, and bone and joints. The large scale is intended to provide sufficient statistical power for reliable assessment of associations between these imaging phenotype measures and a wide range of incident diseases. As with the successful recruitment and baseline assessment phase, the application of highly efficient processes to optimise and manage these imaging assessments has been shown in the pilot phase to allow them to be conducted cost-effectively. The pilot phase has also demonstrated that non-imaging assessments could be conducted in parallel without interfering with the streamlined imaging process. The pilot phase has shown that high quality data can be obtained and that an increasing range of research-ready measures can be derived using automated analysis tools. These imaging data would be available to all bona fide researchers for health-related research that is in the public interest. During and after the main phase of imaging, these dedicated imaging centres could also be used for repeat imaging in subsets of participants to allow investigation of the relevance of changes in imaging measures to various outcomes (e.g. dementia).