Abstract
Objective: To examine the association between intrauterine growth restriction (IUGR) status at birth among full-term infants, exposure to substance use during pregnancy, and risk of hypertension at 6 years of age.
Design: Prospective evaluation of high-risk children.
Setting: Four centers of the National Institute of Child Health and Human Development Neonatal Research Network.
Participants: One thousand three hundred eighty-eight infants (600 cocaine exposed, 781 nonexposed, and 7 indeterminate, matched by gestational age, race, and sex), were enrolled at these sites. Nine hundred fifty children (415 exposed, 535 nonexposed) were followed up for 6 years.
Intervention: Right arm blood pressure was measured using the Dinamap portable adult/pediatric monitor with appropriate cuff size.
Main Outcome Measure: Blood pressure levels. Hypertension was defined as either systolic or diastolic blood pressure higher than the 95th percentile for sex, age, and height.
Results: Eight hundred ninety-one children had blood pressure data at 6 years of age: 516 were born at full term; 144 (28%) of the 516 children had a diagnosis of IUGR at birth. At 6 years of age, 93 (19%) of 516 children had hypertension. Of 144 children with IUGR, 35 (24%) had hypertension as compared with 58 (16%) of 372 children without IUGR (P<.05). Twenty percent of cocaine-exposed children had hypertension as compared with 16% of nonexposed children (P = .20). Intrauterine growth restriction status at birth was significantly associated with hypertension (relative risk, 1.8 [95% confidence interval, 1.2-2.7]) when multivariable Poisson regression analysis was performed adjusting for site; maternal race, education, and tobacco, marijuana, alcohol, and cocaine use during pregnancy; and child's current body mass index (calculated as weight in kilograms divided by height in meters squared).
Conclusion: In term infants, IUGR is linked to risk of hypertension in early childhood, which may be a marker for adult cardiovascular disease.