Persons with type 1 diabetes, type 2 diabetes or even prediabetes are vulnerable to the risk of serious infections, according to a study of more than 800,000 individuals published June 6 in the journal Diabetes (1,2).

In this study, researchers analysed rates of infection in 33,829 people with type 1 diabetes (T1D), 527,151 with type 2 diabetes (T2D), and 273,216 with prediabetes in the UK and compared them with more than one million people without diabetes, who were matched based on age, sex and ethnicity. They examined infections managed in primary care, infections requiring hospitalization, and deaths due to infection, over a period of 5 years from 2015 to 2019.

Results showed that persons with diabetes were at a higher risk of infections than those without diabetes. The risk was greatest among those with T1D and lowest in prediabetes. Although the relative risk of infection was comparable across ethnic groups, South Asians had the greatest overall burden of diabetes-related infections.

Participants with T1D an 81% higher chance of infection diagnosed and managed by their GP and 337% higher risk of being hospitalized for infection, compared to those without diabetes. Patients with type 2 diabetes had a 51% increased risk of primary care infections and 91% increased risk of hospitalization. While those with prediabetes had a 35% increased risk of GP-treated infection and 33% higher risk of hospitalization. In T1D, higher average HbA1c levels were strongly associated with increased risk of infections. But, in T2D, fluctuations in blood glucose levels over time, rather than average levels, contributed significantly to severe infections requiring hospitalization.

A notable finding was that overall infections ranked as the third most common cause of death among individuals with T2D, after cardiovascular disease and cancer. The study also found that infection-related mortality may be underreported, as sepsis is rarely coded as the underlying cause of death. Pneumonia and other lower respiratory tract infections were the leading causes of infection-related hospital admissions in diabetes patients, both type 1 and type 2, while sepsis and respiratory infections were major contributors to infection-related mortality in those with type 2 diabetes.

The study highlights infections as “major health hazard” in patients with diabetes and prediabetes. They are often preventable. Improved glycemic control, early detection and treatment of infections, and strategies to reduce HbA1c variability could help prevent such complications, reduce hospital admissions, and lower mortality among people living with diabetes. Further, it suggests that “infections must be recognised alongside cardiovascular and metabolic complications as a central component of diabetes management”.

“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”, noted Professor Julia Critchley, Professor of Epidemiology from the School of Health & Medical Sciences, the lead researcher.

References

1.    Julia A Critchley, et al. Increased risk of infections in people living with diabetes. Diabetes. 2026 Jun 6:dbi260004. doi: 10.2337/dbi26-0004.

2.    Jones L. City St George’s, University of London News Release. Available at: https://www.citystgeorges.ac.uk/news-and-events/news/2026/june/infections-are-major-health-hazard-for-people-with-diabetes#:~:text=People%20living%20with%20type%201%20diabetes%20were%20at%20the%20highest,compared%20to%20those%20without%20diabetes. Dated June 8, 2026. Accessed on June 12, 2026.