High Infection Rates in Type 2 Diabetes: Periodontitis Prevalence at 33.6%

BACKGROUND: Although evidence suggests a greater susceptibility of type 2 diabetes to infections, the prevalence and incidence of different types of infections vary greatly, affecting clinical decision-making. We aimed to estimate the aggregate prevalence and incidence of infections among people with type 2 diabetes. METHODS: We searched PubMed, Embase, Web of Science, and Cochrane Library from inception to August 2025. We combined the terms type 2 diabetes, infection, and prevalence/incidence for the search. We included studies with data on infection prevalence (percentage) and/or incidence (number of person-years at risk) among patients with type 2 diabetes. We used the quality-effects model to estimate effects and 95% confidence intervals (CIs). RESULTS: We included 70 studies in this meta-analysis. Severe periodontitis had the highest pooled prevalence among people with type 2 diabetes (33.6%; 95% CI = 23.7-44.2), followed by skin infections (28.6%; 95% CI = 20.7-37.2) and urinary tract infections (9.7%; 95% CI = 6.5-13.5). Lower respiratory tract infections had the highest pooled incidence per 10 000 person-years (1409.2; 95% CI = 1048.1-1894.6), followed by skin infections (664.1; 95% CI = 39.4-11203.9), upper respiratory tract infections (553.6; 95% CI = 12.7-24149.2) and urinary tract infections (500.6; 95% CI = 171.3-1462.6). CONCLUSIONS: Among people with type 2 diabetes, the prevalence of severe periodontitis and the incidence of lower respiratory tract infections were the highest. We pinpointed recently prevalent high-occurrence infections in type 2 diabetes, helping to update surveillance and control priorities for diabetes care. REGISTRATION: PROSPERO: CRD42024489267.