Abstract: Objective: To identify the risk factors of post-ICU cognitive impairment by meta analysis. Methods: Databases including PubMed, The Cochrane Library (Issue 4, 2018), Web of Science, EMbase, CBM, CNKI, and Wanfang Data were searched to collect randomized control trials (RCTs), cohort studies and case-control studies about the risk factors of post-ICU cognitive impairment from inception to April 2018. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Meta-analysis was conducted using Revman 5.3. Results: Thirty-eight studies were recruited, including 10 870 cases. The hypoxemia, duration of mechanical ventilation, Charlson Comorbidity index, education level, opioid dose, delirium and duration of delirium were independent predictors of post-ICU cognitive impairment. Conclusion: Because of insufficient evidence on risk factors for post-ICU cognitive impairment and inconsistent evaluation methods of post-ICU cognitive impairment and different follow-up time, more strictly designed original studies are needed to identify the risk factors of post-ICU cognitive impairment.

Key words: Intensive Care Unit (ICU); cognitive impairment; post-intensive care syndrome; risk factors; Meta-analysis