PATIENTS with Type 2 diabetes mellitus (T2D) have faced heightened health risks throughout and since the COVID-19 pandemic, raising concerns among healthcare professionals globally. A recent comprehensive study sought to evaluate and quantify the specific impact of T2D on key COVID-19 outcomes, including death rates, disease severity, and the requirement for mechanical ventilation. A striking finding from the analysis was that people with T2D were over three times more likely to die from COVID-19 than those without the condition.
To conduct the study, researchers carried out a systematic review and meta-analysis following PRISMA guidelines. A broad literature search was performed across PubMed, Scopus, Web of Science and Embase, covering publications from December 2019 to March 2024. The analysis included studies that examined the effect of T2D on adult COVID-19 patients. The researchers employed a random-effects model to synthesise the data and used the I² statistic to assess heterogeneity. They also conducted robust assessments of publication bias, including Egger’s regression and the Fail-safe N test.
The results were consistent and clinically significant across several outcomes. Eighteen studies showed that T2D was linked with a markedly higher risk of mortality (odds ratio [OR]: 3.66; 95% CI: 2.20–5.11; p<0.001), while six studies found increased disease severity (OR: 1.97; 95% CI: 1.02–2.92; p<0.001). Furthermore, five studies indicated a greater need for mechanical ventilation in diabetic patients (OR: 2.34; 95% CI: 1.18–3.49; p<0.001). Heterogeneity was high for mortality outcomes (I²=83.83%) but low for severity and ventilation measures (I²=0%), and no significant publication bias was detected.
These findings carry important implications for clinical practice. The robust association between T2D and poor COVID-19 outcomes highlights the urgency of tailored care strategies for diabetic individuals, including prioritisation in vaccination and early therapeutic interventions. However, the high heterogeneity in mortality data and reliance on observational studies are notable limitations. Further research is essential to uncover the biological mechanisms at play and to refine clinical guidelines for managing patients with T2D in the context of infectious diseases like COVID-19.
Reference
Fatoke B et al. Type 2 diabetes mellitus as a predictor of severe outcomes in COVID-19 – a systematic review and meta-analyses. BMC Infect Dis. 2025;25(1):719
