Post-sepsis cognitive impairment and associated risk factors: A systematic review

Introduction: Post-sepsis cognitive impairment is one of the major sequelae observed in survivors of sepsis. This cognitive impairment can be global or may affect specific domains. A better understanding of these deficits and associated risk factors could influence the care of patients with sepsis. Objective: To perform a systematic review to investigate the presence of cognitive impairment and its associated risk factors among patients who survived sepsis. Methods: The search was conducted in MEDLINE (1966 to March 2017) and EMBASE (1988 to March 2017). We included studies with individuals who were 18 years or older with post-sepsis cognitive impairment. Results: We analysed 577 articles. Sixteen studies met the inclusion criteria. More than 74,000,000 patients were evaluated in the selected studies. Significant variation was observed in the definition of sepsis and cognitive impairment. Twelve studies used ACCP/SCCM criteria for sepsis, while cognitive impairment was defined per test used. Post-sepsis cognitive impairment was observed in 12.5 to 21% of survivors of sepsis. Attention, cognitive flexibility, processing speed, associative learning, visual perception, work memory, verbal memory, and semantic memory were the specific domains affected. Depressive symptoms, central nervous system infection, length of hospitalisation due to infection, and temporal proximity to the last period of infection were associated with cognitive impairment. Conclusion: The studies are heterogeneous, and there is urgent need for a common language, including definitions and neuropsychological tests, for the investigation of post-sepsis cognitive impairment. Despite this, there is mounting evidence for the clinical relevance of post-sepsis cognitive impairment. Systematic review registration: PROSPERO CRD42017054583 (www.crd.york.ac.uk/PROSPERO).