21 March 2014

More Than One in 30 in the UK Participate in Cohort Studies

The Medical Research Council (MRC) today publishes the first review of the UK’s largest cohort studies. The Strategic Review of the Largest UK Population Cohort Studies, which looks at cohorts funded by the MRC and other funders, has found that more than 2.2 million people (3.5 per cent of the population or one in 30) are a participant in a cohort study.

A commentary in The Lancet highlights the MRC’s 50-year history of supporting population cohort studies including the world’s longest continuously running birth cohort (the 1946 Birth Cohort), UK Biobank’stracking of half a million participants, and the largest longitudinal study of women’s health (the Million Women Study). Close to £30m per annum is spent on the 34 largest UK population cohort studies. More than half of these participants have been followed for more than 20 years. The vast majority are aged 45 years or over (92 per cent) and female (62 per cent after exclusion of the Million Women Study), with men aged 20-40 years less well represented.

Population cohort studies are a major long term commitment for participants, study teams and funders, but their strength is in their ability to identify multiple risk factors over time.

Professor Sir John Savill, Chief Executive of the Medical Research Council, said:

“A striking feature to emerge from this review is the number of people involved in cohort studies – over one in thirty people have given up their time to take part in medical research, not simply because they believe they will derive direct benefit but because they wish to contribute to gains in societal health and wellbeing. We owe them a debt of gratitude.

“Participants from the UK cohort studies have given consent for their personal data to be linked to NHS records and other data sources such as education and the census. Linking cohort data to routine health and administrative datasets in safe environments that protect confidentiality increases the scope and scale of research possibilities.”

Investments by the MRC and other partners have created The Farr Institute of Health Informatics Research and the UK Health Informatics Research Network to facilitate data linkage of cohorts to identify the causes of disease, develop personalised treatments and monitor health risks and drug safety.

But Sir John added a warning:

“Long-term investment in cohorts – including the time invested by millions of participants – is at risk from proposed amendments to the EU data protection regulation. It would be a significant backward step if the huge potential of cohorts and other studies using data to improve our understanding of disease was jeopardised by disproportionate legislation.”

The MRC believes population cohort studies are in a prime position to take advantage of high-throughput technologies, such as genomics, when combined with data linkage. (68 per cent of UK cohort studies have undertaken genotyping, and half have epigenetic or metabolomic data.) The inclusion of genotyping in large cohorts with longitudinal phenotypic information enables more robust studies of gene-environment interactions.

Other technologies, such as imaging, also greatly enhance the value of cohorts. The UK Biobank study will soon begin an imaging pilot study, in which participants will undergo detailed imaging of their brains, hearts, bones and blood vessels.

Professor Jill Pell, who chaired the Cohort Strategic Review Subgroup which produced the report, said:

“This is the first time that researchers have had access to an overview of all of these important resources, together with a summary of the types of participants and type of data collected. Some cohorts were well known and well used but some were less well known and this review will heighten awareness of the whole UK cohort portfolio and increase use of these important studies. That means better value for money and a greater impact on health.”

The Lancet commentary concludes:

“In addition to spotlighting individual cohorts, the Review contains a series of recommendations for the MRC and others. While discoverability and sharing of data and samples are already policy for MRC and other funders, more can be done to enable well-governed use of these resources. Findings from the cohorts have great utility for policy and practice in the UK, as well as further afield, and the need for closer working with policy makers is highlighted. It is envisaged that the Strategic Review will act as a signpost and encourage more extensive use of these assets in the future. The UK cohort resources are a national treasure that few other countries can match.”