Infections should be considered a "health hazard" in people living with diabetes, with experts warning that current clinical guidelines fail to reflect a substantial but under-recognised burden of illness, hospitalisation and death. This is according to a major study published today in Diabetes and presented at the American Diabetes Association Scientific Sessions conference in New Orleans.
In one of the largest studies to date, findings reveal that people living with type 1 diabetes, type 2 diabetes and prediabetes face higher risks of infection compared to those without diabetes. These risks span infections managed in primary care, those requiring hospital admission, and deaths related to infection.
Infection was revealed to be the third most common underlying cause of death in type 2 diabetes after cardiovascular disease and cancer.
Researchers who led the study at City St George's, University of London are now calling for infection prevention, early recognition and management to be embedded in diabetes guidelines in the UK and globally.
Using anonymised GP records linked to hospital and mortality data, researchers analysed infection rates of more than 800,000 people across England living with type 1 diabetes (33,829 people), type 2 diabetes (527,151) or prediabetes (273,216), and compared them to over one million controls matched for age, sex and ethnicity. They were assessed over five years.
People living with type 1 diabetes were at the highest risk of infection, with an 81% higher chance of infection diagnosed and managed by their GP and 337% higher risk of being hospitalised for infection, compared to those without diabetes. People with type 2 diabetes had a 51% and 91% increased risk of primary care infections and hospitalisation, respectively, whilst those with prediabetes were at a 35% and 33% increased risk, respectively.
Professor Julia Critchley, Professor of Epidemiology from the School of Health & Medical Sciences at City St George's, University of London, who led the study said:
"Infections are a major health hazard across the diabetes spectrum and are hiding in plain sight. They are common, serious, and often preventable, yet they are mostly absent from clinical guidelines.
"The number of people living with diabetes across the world is on a dangerously steep rise, and it's a disservice if we do not treat infection risk as a core part of diabetes care. It cannot be an afterthought."
Lower respiratory tract infections, such as pneumonia, were the most common infection that required hospitalisation in type 1 and 2 patients. Sepsis and lower respiratory tract infections were the most common cause of infection-related death in people with type 2 diabetes.
They also found that the level and variation in blood sugar levels were linked to increased infection risk. In type 1 diabetes, higher blood sugar levels were linked to increased infection risk. However, in type 2 diabetes, fluctuations over time, rather than average levels alone, were associated with serious infections requiring hospitalisation. This suggests that some patients with seemingly good blood sugar control may still be at elevated risk if their levels vary significantly between clinic visits.
The researchers say infections must be recognised alongside cardiovascular and metabolic complications as a central component of diabetes management. They argue that guidelines should explicitly address infection risk, measures for improved blood sugar control, support stronger patient messaging around early presentation with symptoms, and encourage adaptations to primary care triage systems so that people with diabetes are prioritised for rapid assessment and treatment.
Professor Julia Critchley added: "Increased infection risk in diabetes should have greater emphasis in UK, European and US guidance. By refreshing guidance on a global scale, it will increase awareness amongst healthcare workers to aid earlier recognition and prompt intervention, which would help reduce avoidable hospital admissions and deaths."
The study was funded by the National Institute for Health and Care Research (NIHR).
