A recent study has found that a genetic predisposition to a fatty liver is key to the risk of developing type 2 diabetes.
The study, funded by Diabetes UK and led by Dr Hanieh Yaghootkar, a Diabetes UK RD Lawrence Fellow at Brunel University, used statistics to gather genetic data to understand whether liver and pancreas size, and fat content influence the risk of developing type 2 diabetes. The findings were published in Diabetes Care.
'People with type 2 diabetes usually have excess fat in their liver and pancreas, the two key organs in the maintenance of the normal level of blood sugar.' said Dr Yaghootkar. 'The genetic analysis we used in this study is the best possible method to test this relationship and we provided evidence for a causal role of liver fat in type 2 diabetes risk.'
Non-alcoholic fatty liver disease occurs when fat builds up in the liver and is most often seen in overweight and obese people. This is often characterised by elevated liver enzymes. Having higher levels of liver fat has previously been associated with type 2 diabetes. However, this new study provides the strongest evidence to date implicating liver fat and pancreas size in this condition.
The team analysed MRI data from over 30,000 people previously part of a UK Biobank study. Liver and pancreas fat and size were analysed alongside genetic information affecting these factors. The study highlighted two sets of genes associated with a higher risk of type 2 diabetes, one set of variants associated with liver fat and the other with pancreatic volume. Those with a genetic propensity to store fat in the liver a had a higher risk for type 2 diabetes. It was found that for every five percent increase in liver fat, the risk of type 2 diabetes increased by 27 percent. No association was found between liver size and type 2 diabetes.
This study is the first to provide genetic evidence of a causal link between decreased pancreatic volume and type 2 diabetes. Conversely, no association was found between higher pancreatic fat and type 2 diabetes.
The researchers emphasise that type 2 diabetes is complex with various risk factors, some of which are unchangeable such as age, ethnicity, and family history, and some changeable, such as weight. Understanding how these different factors impact the risk of developing type 2 diabetes is important to establish the most effective ways to help people reduce their risk.
This research allows for a more personalised treatment approach. There are currently 4.1 million people in the UK diagnosed with diabetes. This research may help to identify those with a genetic makeup making them prone to higher liver fat levels or a smaller pancreas, allowing for tailored support to help them take steps to reduce their risk of type 2 diabetes early on.
Dr Yaghootkar concluded that 'our results encourage better treatment of those living with non-alcoholic fatty liver disease, and provide evidence for the multiple benefits of weight loss and better screening for diabetes risk in these people.'