Neonates with low gestational age and birthweight at increased risk of elevated BP and CKD

USA: In a new study published in the Clinical Journal of the American Society of Nephrology, it was shown that the risk of chronic kidney disease (CKD) was found to be associated with gestational age, birthweight z-score, and prenatal steroids in neonates with extremely low gestational ages.

Chronic illness is a danger for neonates born at extremely low gestational ages (less than 28 weeks). Sangeeta Hingorani and colleagues conducted this study in order to describe the prevalence of renal outcomes by gestational age and identify risk factors for their development.

The Preterm Epo Neuro Protection Trial (PENUT) trial included neonates born at exceptionally low gestational ages, and the Recombinant Erythropoietin for Protection of Infant Renal Disease (REPAIReD) study assessed kidney outcomes. At 2 years (24±2 months) corrected gestational age, kidney function, urine albumin, and blood pressure were assessed. Results from various gestational age groups were examined, and correlations between kidney-related outcomes and maternal and neonatal traits were assessed. Secondary objectives included spot urine albumin-creatinine ratio ≥30 mg/g (albuminuria) and either systolic BP or diastolic BP >90th percentile for height, age, and sex. The primary outcome was eGFR 90 ml/min per 1.73 m2 (CKD).

The key highlights of this study were:

1. 832 people in all reached the 2-year mark, and 565 (68%) of them had at least one outcome assessed.

2. In all, 297 patients (53%) had one abnormal kidney outcome, including 61 (18%) with an eGFR less than 90 ml/min per 1.73 m2, 155 (36%) with albuminuria, 65 (22%) with raised systolic blood pressure, and 128 (44%) with high diastolic blood pressure.

3. Prenatal steroids, birth weight z-score, and gestational age were linked to an eGFR of less than 90 ml/min per 1.73 m2.

4. Black race and indomethacin usage was linked to raised systolic blood pressure; severe AKI, male sex, and indomethacin use were linked to elevated diastolic blood pressure. 

In conclusion, these findings highlight the need for neonatologists and nephrologists to talk to family members and other medical professionals before releasing preterm newborns from the neonatal intensive care unit about the risk of renal problems and high blood pressure.

Researchers advise testing serum creatinine and cystatin C, urine for the albumin-creatinine ratio, and blood pressure at about 2 years of age in all infants of exceptionally low gestational age. Repeat assessments and follow-up with a nephrologist are recommended for those with abnormal results. 

Reference: 

Hingorani, S., Schmicker, R., Ahmad, K. A., Frantz, I. D., Mayock, D. E., La Gamma, E. F., Baserga, M., Khan, J. Y., Brophy, P., & Askenazi, D. (2022). Prevalence and Risk Factors for Kidney Disease and Elevated BP in 2-Year-Old Children Born Extremely Premature. In Clinical Journal of the American Society of Nephrology (Vol. 17, Issue 8, pp. 1129–1138). American Society of Nephrology (ASN). https://doi.org/10.2215/cjn.15011121