Diabetes mellitus is a common comorbidity in chronic obstructive pulmonary disease (COPD), but its effect on outcomes during acute exacerbation of COPD (AECOPD) remains uncertain. A meta-analysis published in BMC Pulmonary Medicine evaluated the association between diabetes and mortality risk in patients with AECOPD.

The analysis included cohort and case-control studies identified through searches of PubMed, Embase, Cochrane Library, Web of Science, CNKI, and Wanfang databases through March 2026. Nine studies involving 23,883 participants were included. Risk of bias was assessed using the Newcastle-Ottawa Scale (NOS), and pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated using meta-analytic methods.

Findings

• In univariate analyses, diabetes was associated with increased mortality risk in patients with AECOPD (HR 1.45; 95% CI, 1.19-1.77; p<0.0001).
• Multivariate analyses did not show a significant independent association between diabetes and mortality risk (HR 1.50; 95% CI, 0.45-5.00; p=0.513).
• Subgroup analyses showed increased mortality risk among hospitalized patients with AECOPD, but not among patients admitted to ICUs.
• Significant associations were observed in case-control studies and in studies with sample sizes greater than 1,000 participants, but not in cohort studies or smaller studies.

The findings suggested that associations between diabetes and mortality in AECOPD may be influenced by study design and methodological factors. Current evidence did not support diabetes as an independent risk factor for mortality in AECOPD.