Evaluating Ethnic Variations in the Risk of Infections in People With Prediabetes and Type 2 Diabetes: A Matched Cohort Study

People living with type 2 diabetes (T2D) are at higher infection risk, but it is unknown how this risk varies by ethnicity or whether the risk is similarly observed in people with nondiabetic hyperglycemia ("prediabetes").

We included 527,151 patients in England with T2D and 273,216 with prediabetes, aged 18-90, and alive on 1 January 2015 on the Clinical Practice Research Datalink. Each was matched to two patients without diabetes or prediabetes on age, sex, and ethnic group. Infections during 2015-2019 were collated from primary care and linked hospitalization records. Infection incidence rate ratios (IRRs) for those with prediabetes or T2D were estimated, unadjusted and adjusted for confounders.

People with T2D had increased risk for infections presenting in primary care (IRR 1.51, 95% CI 1.51-1.52) and hospitalizations (IRR 1.91, 1.90-1.93). This was broadly consistent overall within each ethnic group, although younger White T2D patients (age <50) experienced a greater relative risk. Adjustment for socioeconomic deprivation, smoking, and comorbidity attenuated associations, but IRRs remained similar by ethnicity. For prediabetes, a significant but smaller risk was observed (primary care IRR 1.35, 95% CI 1.34-1.36; hospitalization IRR 1.33, 1.31-1.35). These were similar within each ethnicity for primary care infections, but less consistent for infection-related hospitalizations.

The elevated infection risk for people with T2D appears similar for different ethnic groups and is also seen in people with prediabetes. Infections are a substantial cause of ill-health and health service use for people with prediabetes and T2D. This has public health implications with rising prediabetes and diabetes prevalence.