Diurnal urinary aldosterone excretion and potassium intake during pregnancy are associated with high normal blood pressure in early childhood

BACKGROUND: Offspring blood pressure (OBP) may be programmed during pregnancy. Accordingly, maternal third-trimester 24-hour urine aldosterone levels are associated with fetoplacental trophic effects. Furthermore, high potassium and low sodium intakes are generally recommended in adults with normal renal function. We hypothesized that maternal 24-hour urine aldosterone levels were positively associated with OBP, and maternal intake of potassium and sodium may influence the association. The study aimed to investigate associations between maternal third-trimester 24-hour urine aldosterone, potassium and sodium intake, and OBP. METHODS: In the prospective OCC (Odense Child Cohort), 475 mother-child dyads had 24-hour urine aldosterone from gestational week 29 and OBP (systolic and diastolic), at ages 3 and 18 months and 3 and 5 years. Maternal potassium and sodium intakes were calculated from 24-hour urine potassium and urine sodium excretions. RESULTS: Increased maternal 24-hour urine aldosterone associated with higher systolic blood pressure in offspring at ages 3 months (β=0.54 mm Hg [95% CI, 0.29; 0.79]) and 18 months (β=0.24 mm Hg [95% CI, 0.03; 0.44]). One thousand mg/d increase in maternal potassium intake was associated with an average increase in offspring systolic blood pressure of 0.68 mm Hg (95% CI, 0.02-1.34) up to age 5 years (pooled), with significant associations only in girls (β=1.14 mm Hg [95% CI, 0.21-2.08]). No significant association was seen between maternal sodium intake and OBP. CONCLUSIONS: Elevated maternal 24-hour urine aldosterone and higher dietary potassium intake were associated with higher OBP but within normal range in young children, and girls were more susceptible to maternal potassium intake. REGISTRATION: URL: https://clinicaltrials.gov. Unique identifier: ID NCT02183558.