Albuminuria, Hypertension, and Reduced Kidney Volumes in Adolescents Born Extremely Premature

Abstract

Background: Premature birth is associated with decreased nephron number and an increased risk for chronic kidney disease (CKD). To inform the development of guidelines for kidney follow up of children born prematurely, we undertook a study of individuals born extremely preterm, with the aim of characterizing the prevalence and predictors of microalbuminuria, elevated blood pressure, and/or abnormal kidney volume in adolescence. Methods: Study participants (n = 42) were born before 28 weeks of gestation and were enrolled at birth in the Extremely Low Gestational Age Newborns (ELGAN) study. When participants were 15 years old, we obtained 2 manual blood pressures, a spot urine microalbumin measurement, and sonographic measurements of kidney length and volume. Results: Of the 42 participants, 60% were male, 52% were Caucasian (18% Hispanic), and 43% were African-American. Their median age was 15 (IQR 15, 15.3) years. In 33.3% of the cohort, blood pressure was elevated (>120/80 mmHg). Microalbuminuria (>30 mg/g) was present in 11.9% of the cohort, and kidney volume below the 10th percentile of normative data was present in 14%. Twenty-one (50%) of the sample had at least one kidney abnormality (microalbuminuria, elevated blood pressures, and/or kidney hypoplasia); these individuals were more likely to have experienced neonatal hypotension [55% vs. 17% among those with no kidney abnormality, p = 0.02]. Conclusions: Half of adolescents in this subset of ELGAN cohort have at least one risk factor of kidney disease (reduced kidney volume, microalbuminuria, and/or elevated blood pressures) at 15 years of age. This study suggests the importance of monitoring kidney outcomes in children after extremely preterm birth, especially those with a history of neonatal hypotension.

Compensatory Hypertrophy in Paediatric Patients with a Unilateral Ureteropelvic Junction Obstruction

“…We found that 35% of the patients in our study showed signs of kidney injury, but we did not observe associations between signs of kidney injury and any of the determinants in our cohort, despite previously reported associations [27] , [28] . Most likely, the absence of such associations is due to a lack of power in our study.…”

Postnatal Expression Profile of MicroRNAs Associated with Cardiovascular Diseases in 3- to 11-Year-Old Preterm-Born Children

“…The highest postnatal microRNA expression levels were observed in children born prematurely at lower gestational ages and in children born with lower birth weight. These findings may also contribute to the explanation of why preterm-born children with lower birth weight have an increased cardiovascular risk and to the explanation of the increase in cardiovascular risk with the decrease in gestational age at delivery [2,5,[9][10][11]15,19,20,22,23,26,27,29,31,35,39,43,44,51,58,59].…”

“…In general, multiple risk factors predisposing to a later development of cardiovascular diseases have been identified in preterm-born individuals. These risk factors involve increased peripheral and central systolic (SBP) and/or diastolic (DBP) blood pressures , higher heart rate (HR) [4,22,23], higher fat mass [21], lower functional skin capillary density [4], lower peripheral skin blood flow [24], abnormal retinal vascularization (both structure and function) [1,3,17], increased sympathoadrenal activity together with higher levels of urine catecholamines [22], kidney hypoplasia, incomplete nephrogenesis (reduced number of nephrons) and impaired renal function (decreased glomerular filtration rate, microalbuminuria) [20,[25][26][27][28], worsened respiratory parameters usually as a consequence of bronchopulmonary dysplasia (BPD) [19,29,30], impaired exercise capacity [19,30], elevated fasting glucose and cholesterol levels [10], higher serum levels of insulin 2 h after the glucose load [31], decreased insulin sensitivity [32][33][34][35][36], or even higher incidence of systolic or diastolic prehypertension/hypertension [13,25,[37][38][39][40], chronic kidney disease [13,25], lipid disorders [39,41], type 1 diabetes mellitus [39,[42]…”

Effects of prematurity on long-term renal health: a systematic review

“…16 Sanderson et al found approximately 5 (11.9%) of their 42 premature children had microalbuminuria at 15 years of age. 42 Keijer Veen et al reported microalbuminuria in two patients of their premature small for gestational age group. 22 However, none of their participants in the premature appropriate for gestational age group or term group was found to have microalbuminuria.…”

“…Sanderson et al found that of their 42 premature participants, approximately 14 (33.3%) had elevated BPs at 15 years of age. 42 Askenazi et al found that of their 923 extremely low gestational age participants at 22-26 months of age, approximately 212 (23%) have a systolic BP >95th percentile for their age and approximately 369 (40%) had a diastolic BP >95th percentile. 45 Proteinuria/albuminuria Nineteen studies commented on proteinuria or albuminuria.…”