Avaliação da relação entre o nascimento prematuro, baixo peso ao nascer e déficit da função renal

Abstract

This thesis aimed to evaluate the relationship between preterm birth, low birth weight (LBW) and impaired renal function. To this end, two studies were developed. The first was an integrative literature review with the aim of gathering the most recent scientific publications on the influence of prematurity on the development of chronic kidney disease (CKD). Publications from 2016 to 2020, in Portuguese and English, were considered that addressed the relationship between prematurity and development of kidney disease, as well as the mechanisms that explain this association, based on the hypothesis that preterm newborns are most vulnerable to CKD. The search strategy was carried out using the electronic databases USA National Library of Medicine (Medline/PubMed), Virtual Health Library (Bireme/Lilacs) and Cochrane Library, from the combination and free use of terms indexed on the Mesh platform: premature birth; infant, premature; kidney disease; kidney failure, chronic; renal insufficiency. Initial selection was performed by two independent evaluators, with screening of articles of interest based on the evaluation of titles and abstracts. When not enlightening, the article was read in full. Repeated articles were excluded and disagreements between evaluators were resolved by consensus. Qualitative analysis of studies was used for synthesis and interpretation of results. Recent studies have shown the effect of prematurity on the risk of developing CKD, although more robust evidence is needed to guide formal guidelines for monitoring children born prematurely, from childhood to adulthood. The second was a cross-sectional study, with the objective of evaluating the association of renal deficit with maternal characteristics and in LBW children discharged from the Neonatal Intensive Care Unit (NICU). Maternal and child-related data were obtained through electronic medical records and outpatient consultations. To estimate the glomerular filtration rate (GFR) the combined equation of Zapittelli (2006) was used. A logistic regression analysis was performed in which renal deficit, represented by GFR<60 mL/min/1.73m², was an outcome variable and maternal characteristics, independent variables. Confounding variables related to children were controlled for. The prevalence of deficit in renal function among the 154 children evaluated was 34.42%. Most children with impaired renal function were male (56.6%), gestational age >32 weeks (56.6%), mean birth weight of 1439.7±347.5 grams and mean estimates of GFR of 46.9±9.3 mL/min/1.73m². During the evaluation period, children who were heavier had a lower risk of developing renal function deficit (OR=0.803; CI=0.650-0.993) and having used nephrotoxic drugs during NICU stay increased the chance of this deficit (OR=2.781; IC=1.095-7.061). It is concluded that weight may act as a protective factor for renal function deficit among children who were born with low birth weight, while the use of nephrotoxic drugs during NICU admission increases the chance of this deficit. The maternal characteristics evaluated were not related to impaired renal function.