Risk factors associated with acute kidney injury in patients with traumatic brain injury: A systematic review and meta-analysis

Purpose This systematic review and meta-analysis aimed to identify and quantify the risk factors associated with acute kidney injury (AKI) in patients with traumatic brain injury (TBI). Methods PubMed, Embase, and Web of Science were systematically searched for articles published up to October 2024. Observational studies published in English that reported on risk factors for AKI in TBI patients were included. Data on AKI incidence and risk factors were extracted. A meta-analysis was conducted using a random-effects model when heterogeneity I-2 > 50 % and a fixed-effects model when I-2 < 50 %. Risk of bias for studies was assessed using the Newcastle-Ottawa Scale (NOS). Certainty of evidence was evaluated using the GRADE approach. Results Twenty studies involving 13,115 TBI patients were included in the meta-analysis. The pooled incidence of AKI after TBI was 19 % (95 % CI 16-23). Male gender (odds ratio (OR) 1.43, 95 % CI 1.21-1.70; I-2 0 %), diabetes (OR 3.59, 95 % CI 1.74-7.42; I-2 0 %), Glasgow Coma Scale (GCS) (mean difference (MD) -0.48, 95 % CI -0.74,-0.23; I-2 38 %), GCS <= 8 at admission (OR 1.56, 95 % CI 1.28-1.90; I-2 0 %), Simplified Acute Physiology Score II (SAPS II) score (MD 4.65, 2.69-6.61; I-2 56 %), serum creatinine level at admission (MD 18.17, 95 % CI 1.82-34.51; I-2 93 %), hemoglobin (MD -6.82, 95 % CI -12.72, -0.92; I-2 79 %), glucose (MD 1.42, 95 % CI 0.64-2.20; I-2 0 %), the use of mannitol (OR 2.14, 95 % CI 1.08-4.25; I-2 74 %), vancomycin (OR 1.75, 95 % CI 1.35-2.27; I-2 0 %) and red blood cell transfusion (OR 3.35, 95 % CI 1.86-6.04; I-2 59 %) increased the risk for AKI. Conclusion These findings highlighted the critical need for proactive surveillance of these risk factors in clinical practice, enabling the development of prediction models to identify TBI patients at high risk of AKI.