Can the analysis of health data demonstrate which people with higher BMI levels are most at risk of developing non-alcoholic fatty liver disease?
human liver

For many years, obesity was assumed to have a connection with non-alcoholic fatty liver disease (NFALD), based on research involving small numbers of patients.

A large-scale research confirmed the link between a rising BMI and the diagnosis of NAFLD. Moreover, it showed for which people this link is stronger.

This research studied the records of just over 2 million patients who had the necessary data recorded, and who did not have other conditions that would affect BMI or NAFLD.

Read on to learn how sharing health data can save lives

Why was this work needed?

Non-alcoholic fatty liver disease (NAFLD) is usually a harmless condition of the liver. However, in some people it can proceed to inflammation of the liver which can then lead on to liver cirrhosis. Liver cirrhosis gradually destroys the liver’s cells so that the liver eventually fails. We are unable to live without a liver.

A link between obesity and NAFLD has been assumed for many years because of findings from previous research studies involving small numbers of patients.

A large-scale research was needed to better understand the connection between BMI and NAFLD, and to study which people with different BMI levels over time do eventually develop NFALD, and which do not.

What did research find?

The results showed that there was a continuous and strong link between a rising BMI and the diagnosis of NAFLD. The link was stronger for men and for people with diabetes.

What was the impact on patients?

This information is useful for patients, as well as for public health organisations and clinicians, when considering preventative health measures to reduce the likelihood of NAFLD for patients who are overweight or obese. This research highlights the patients at highest risk of NAFLD, on whom regular liver function tests can be performed.

What data was used?

Two large anonymised health data sources were used in the research: the Health Improvement Network (THIN) in the UK and Humedica in the US.

Starting with data on over 30 million patients, the research eventually studied the records of just over 2 million patients who had the necessary data recorded, and who did not have other conditions that would affect BMI or NAFLD.

The data from these sources contained routinely collected patient data from GPs, specialty care and hospitalisations in the years of 2007–2013, which had been carefully anonymised. Hence, a formal legal basis in accordance with the European General Data Protection Regulation (GDPR) was not required.

The number of patient records examined in this research (2 million) would probably never have been possible if this study had bene undertaken as a conventional medical trial, or if it had been necessary to seek the consent in advance of 2 million patients.

Who funded and collaborated on this work?

The research was conducted by a collaborative team of research scientists from the British Heart Foundation, the University of Glasgow, Pfizer and GlaxoSmithKline.

It was supported by the Innovative Medicines Initiative Joint Undertaking under Grant Agreement 115372, composed of financial contribution from the European Union’s Seventh Framework Programme (FP7/2007-2013) and European Federation of Pharmaceutical Industries and Associations companies’ in kind contribution.

(*) Body Mass Index (BMI) is a calculation, based on a person’s weight and height, to measure the extent to which someone is overweight or obese

This work uses data provided by patients and collected by the health professionals as part of the care and support provided.

i~HD