Big data to advance health
Big data has become a hot topic in the field of research, but data collection and analysis have been driving innovation for decades, as BHF Professor John Danesh tells Sarah Kidner.
Epidemiology is vital in furthering our understanding of what causes diseases and how to prevent and treat them. But what is epidemiology and how can it help us in the fight against cardiovascular disease (CVD)?
Put simply, epidemiology means exploring the bigger picture of what causes diseases. Professor John Danesh, BHF Chair of Epidemiology and Medicine, explains. “Epidemiology is the study of the causes of disease in populations, what drives the rates of disease up and down. It comes from the same stem as ‘epidemic’,” he says. “Chronic diseases are epidemics in the UK and in many other countries, with CVD foremost among them. About one in every two adult deaths worldwide is due to CVD.”
The most important skill is asking the right questions
Professor Danesh’s ultimate aim is to advance our knowledge of how nature and nurture work together to cause CVD. To achieve this, he is studying detailed information about large numbers of people. This type of information is increasingly being referred to as ‘big data’.
“In addition to helping understand molecular events leading to a heart attack, an epidemiologist studies the interplay of lifestyle, genetic make-up and the broader environment in the causation of disease,” says Professor Danesh. “This integrative perspective and the ability to move across different scales of observation –from the molecular to the individual to the population – is what makes epidemiology distinctive.”
Epidemiologists harvest information from diverse sources, through extensive studies. Professor Danesh has built several such studies. He currently leads EPIC-CVD, a study of the interplay of lifestyle and genetic make-up in more than half a million people, from 10 European countries.
“It was originally set up to look at cancer, but with support from the BHF and other funders, we have created a pan-European component in relation to both coronary heart disease and stroke,” says Professor Danesh.
The recent big data revolution in medicine partly relates to advances in tools, such as genetic and biochemical measurements
About a decade ago, he established the Emerging Risk Factors Collaboration. This consortium of scientists from 25 countries has pooled detailed information on clinical risk factors for 2.5 million individuals. The project has yielded major insights into the management of cardiovascular risk.
More recently, Professor Danesh established INTERVAL, which aims to find the optimum amount of time between blood donations, for donors of different ages, genders and genetic profiles.
The study followed 50,000 people donating blood through NHS Blood and Transplant (NHSBT) centres across England, between 2012 and 2014. Participants gave blood at either usual donation intervals or more frequently, and agreed to be re-contacted to participate in detailed studies of disease mechanisms.
Working with vast data sets such as these demands a range of skills – from finding imaginative ways to recruit participants to data analysis. “Epidemiology is one of the best examples of team science,” says Professor Danesh. “Our team includes cardiologists, geneticists, biochemists, nutritional scientists, statisticians and computer programmers. It’s that collective that defines the kind of epidemiology we do.”
Across these disciplines, perhaps the most important skill is asking the right questions. “Our studies are driven by our questions,” says Professor Danesh.
So what’s this got to do with the buzzwords ‘big data’? “Epidemiology has always been about big data, because identifying and characterising disease risk factors in populations is intrinsically data-hungry,” says Professor Danesh.
“The recent big data revolution in medicine partly relates to advances in tools, such as genetic and biochemical measurements. These provide very extensive, sometimes even comprehensive, information about a biological domain. We can now measure haystacks of biology in large numbers of people, which we hope will help us find the needles responsible for disease.”
Professor Danesh believes epidemiology can play a major role in fulfilling the potential of big data to advance health. “A major challenge in medical research is connecting extensive biological information on large numbers of people with equally extensive information on lifestyle, the environment and health records.
Epidemiology – with its numerical tradition and wide- angle perspective – is ideally placed to help achieve this grand convergence. This is a very exciting time.”
BHF Professor John Danesh
Professor Danesh is BHF Chair of Epidemiology and Medicine at the University of Cambridge, a European Research Council Senior Investigator and a UK National Institute of Health Research Senior Investigator. He is head of a 400-strong department, working together to study populations around the world to help improve the prediction and prevention of CVD.