Risk factors for acute kidney injury in very-low birth weight newborns: a systematic review with meta-analysis

This study aims to analyze the main risk factors for acute kidney injury in the subgroup of very-low birth weight newborns, using the diagnosing criteria of the Kidney Disease Improving Global Outcomes (KDIGO) or the Acute Kidney Injury Network (AKIN). A systematic review of the literature was performed on the EMBASE^® and PubMed^® platforms. Studies that evaluated the risk factors for developing AKI in VLBW newborns were included. For the meta-analysis, we only included the risk factors that were associated with AKI in the univariate analysis of at least two studies. After an initial screening, abstract readings, and full-text readings, 10 articles were included in the systematic review and 9 in the meta-analysis. The incidence of AKI varied from 11.6 to 55.8%. All the studies have performed multivariate analysis, and the risk factors that appeared most were PDA and hemodynamic instability (use of inotropes or hypotension), sepsis, and invasive mechanical ventilation. After the meta-analysis, only cesarian delivery did not show an increased risk of AKI, all the other variables remained as important risk factors. Moreover, in our meta-analysis, we found a pooled increased risk of death in newborns with AKI almost 7 times.  Conclusion: AKI in VLBW has several risk factors and must be seen as a multifactorial disease. The most common risk factors were PDA, hemodynamic instability, sepsis, and invasive mechanical ventilation. What is known: • Acute kidney injury is associated with worst outcomes in all ages. It´s prevention can help diminish mortality. What is new: • A synthesis of the main risk factors associated with AKI in very low birth weight newborns.