Associations Between Prematurity, Birthweight, and Adolescence Blood Pressure in a Nationwide Cohort

Abstract

Introduction: Prematurity is associated with incomplete nephrogenesis and an increased incidence of acute kidney injury, that may increase the risk of future kidney disease, including hypertension, proteinuria and reduced glomerular filtration rate. The aim of this study was to evaluate the risk of hypertension or proteinuria in adolescents born prematurely or small for gestational age, in a nationwide cohort.

Methods: The study cohort included potential recruits examined in the Israel Defense Forces (IDF) medical facilities, between November 2005 and October 2018. Clinical and anthropometric data, including blood pressure (BP) measurement, were retrieved from the IDF medical files. Adolescents born between January 1993 and December 2000 had additional data on gestational age at birth, retrieved from the Israeli Ministry of Health database.

Results: The study cohort included 513,802 participants, aged 17.3 ± 0.9 years, of whom 48,994 had gestational age data. Adolescents born as very preterm, as extremely preterm infants, those born with very low birthweight (VLBW), or with extremely low birthweight (ELBW) had higher incidence of hypertensive-range BP (55%, 47%, 19% and 12%, respectively). No significant association between birthweight (BW) adjusted to gestational age and hypertension was observed. Within the overweight and obese adolescents, those born with VLBW and ELBW, had further increased hypertensive-range BP rate. Proteinuria was diagnosed in 0.33% of the study cohort, with no significant difference between BW or gestational age categories.

Conclusion: Adolescents born with VLBW or as significant preterm were associated with high BP and should be monitored for hypertension development and its potential complications.

Keywords: acute kidney injury; adolescent hypertension; birthweight; chronic kidney disease; prematurity; proteinuria.

Graphical abstract

Figure 1

Consort flow diagram of study participants. IDF, Israel Defense Forces.

Figure 2

Prevalence of hypertensive-range BP in different birthweight groups (normal, LBW, VLBW, ELBW, and high BW). BP, blood pressure; BW, birthweight; ELBW, extremely low birthweight; LBW, low birthweight; VLBW, very low birthweight. ∗Statistically significant difference from normal BW, P < 0.001.

Figure 3

Prevalence of hypertensive-range BP in different birthweight groups (normal, LBW, VLBW, ELBW, and high BW) according to BMI subgroups (underweight, normal, overweight, and obese). BMI, body mass index; BW, birthweight; ELBW, extremely low birthweight; LBW, low birthweight; VLBW, very low birthweight.

Figure 4

Predictors of hypertensive-range BP in the entire cohort (N = 513,802) presented as odds ratio and 95% confidence interval. ELBW, extremely low birthweight; LBW, low birthweight; VLBW, very low birthweight.

Figure 5

Predictors of hypertensive-range BP in the smaller cohort (n = 48,994) presented as odds ratio and 95% confidence interval. BW, birthweight; ELBW, extremely low birthweight; LBW, low birthweight, VLBW, very low birthweight; ELBW, extremely low birthweight.