Diabetes consultants at the Queen Elizabeth Hospital Birmingham (QEHB) have found that the most common test for type 2 diabetes is less accurate for patients with some health conditions.

The HbA_1c test measures the sugar levels in people’s blood over the previous three months, with higher levels of blood glucose being a strong indicator for having diabetes.

The trial looked at a cohort of patients who have other medical illnesses, with the results finding that for people with liver diseases such as cirrhosis that are linked with severe anaemia, the test either fails to recognise diabetes or leads to under-treatment.

This is one of the first studies to estimate how much the HbA_1c test is affected by other medical conditions. Other illnesses and drug treatments that cause anaemia are also thought to affect the accuracy of the test.

The trial, which has now been published in a diabetes journal, will influence how diabetes is diagnosed in the future, with alternative methods of diagnosis being investigated for patient groups where the HbA_1c test is not accurate.

Dr Jonathan Webber, Diabetes Consultant at QEHB, said: “The results of our trial will be very useful globally, and we have already fed back our results to the US National Glycohemoglobin Standardisation Program, the international body that standardises the test results.

“Diabetes is an increasingly common condition, but early diagnosis and treatment can really help reduce the risk of complications.

“Tests such as HbA_1c are important in diagnosing people with diabetes but our results have suggested that for a few patients, alternative tests will be required.”

Dr Webber worked alongside colleagues at QEHB including Dr Sandip Ghosh and Dr Susan Manley. Dr Manley has presented research on this topic at international conferences around the world, including the American Diabetes Association meeting in June 2019.

A link to the full paper and to information about diabetes services at QEHB can be found below.