Reduced kidney function and hypertension in adolescents with low birth weight, NHANES 1999–2016.

Background: Chronic kidney disease (CKD) is a major health problem, and the risk of CKD and hypertension in children born low birth weight (LBW) is under-recognized. We hypothesized that children born with LBW would have a higher prevalence of reduced kidney function and hypertension. Methods: Using the National Health and Nutrition Examination Survey (NHANES), we conducted a cross-sectional study to evaluate whether LBW (< 2500 g), very low birth weight (VLBW < 1500 g), and large birth weight (BW) (> 4000 g) were associated with kidney disease using 4 different estimating equations. We used the Counahan–Barratt, updated Schwartz, CKiD-U25, and full age spectrum creatinine-based GFR estimating equations to evaluate associations between a history of LBW/VLBW/large BW and reduced kidney function (eGFR < 90 mL/min/1.73 m2) in children. We also assessed blood pressure (BP) using the old and new pediatric hypertension guidelines. Results: Our analysis included 6336 children (age 12–15 years) in NHANES representing over 13 million US individuals. Using the updated Schwartz, the prevalence of reduced kidney function was 30.1% (25.2–35.6) for children born with LBW compared to 22.4% (20.5–24.3) in children with normal BW. Equations yielded different estimates of prevalence of reduced kidney function in LBW from 21.5% for Counahan–Barratt to 35.4% for CKiD-U25. Compared to those with normal BW, participants with LBW and VLBW had a 7.2 and 10.3% higher prevalence of elevated BP and a 2.4 and 14.6% higher prevalence of hypertension, respectively. Conclusions: Children born with LBW are at higher risk of reduced kidney function and hypertension than previously described. [ABSTRACT FROM AUTHOR]