Incidence and predictors of acute respiratory distress syndrome in sepsis: a systematic review and meta-analysis

Background: Acute respiratory distress syndrome (ARDS) is a serious and frequent complication of sepsis, carrying a high risk of both morbidity and mortality. Despite extensive research on ARDS in patients with sepsis, the reported incidence and associated risk factors remain inconsistent, with findings varying considerably across clinical settings. Objective: To systematically evaluate the pooled proportion (cumulative incidence) of ARDS among adult patients with sepsis and to identify independent risk factors associated with its development. Methods: A comprehensive search of PubMed, Embase, Cochrane Library, Web of Science, and Scopus was performed for studies published up to May 30, 2025. Observational studies reporting ARDS incidence or risk factors in adult septic populations were included. Data extraction and quality assessment were performed independently by two reviewers to minimize bias. Pooled estimates were generated using a random-effects model, while heterogeneity across studies was quantified with the I² statistic. Potential publication bias was examined using both Egger’s and Begg’s tests. Results: A total of 24 studies involving 23,394 septic patients were included. The pooled incidence of ARDS among septic patients was 34.0% (95% CI: 29.0–39.3%), with considerable heterogeneity (I² = 96.5%). Significant risk factors for ARDS included pneumonia (OR = 2.88, 95% CI: 2.07–3.99), pancreatitis (OR = 2.45, 95% CI: 1.87–3.21), septic shock (OR = 1.78, 95% CI: 1.38–2.31), smoking (OR = 2.23, 95% CI: 1.33–3.75), elevated Sequential Organ Failure Assessment (SOFA) (OR per point = 1.15, 95% CI: 1.10–1.21) and APACHE II scores (OR per point = 1.12, 95% CI: 1.04–1.20), CRP (OR = 1.01), and serum creatinine (Scr) (OR = 1.07). No significant association was found for age, gender, diabetes, or cirrhosis. Conclusion: ARDS complicates approximately one-third of sepsis cases, with its development strongly associated with infection site, disease severity, and systemic inflammation. Routine evaluation of clinical and biochemical markers, including SOFA and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores, pneumonia, and C-reactive protein (CRP) levels, may aid in early risk stratification. These findings support the need for targeted monitoring and prevention strategies in high-risk septic patients. Systematic review registration: https://www.crd.york.ac.uk/PROSPERO, (CRD420251118623).