Abnormal antenatal Doppler velocimetry and cognitive outcome in very-low-birth-weight infants at 2 years of age.
OBJECTIVE
To study neurodevelopmental outcome at 2 years of corrected age in very-low-birth-weight (VLBW) (< or = 1500 g) preterm infants with abnormal fetoplacental flow.


METHODS
A total of 258 VLBW infants were born at Turku University Hospital between 2001 and 2006. Of these, 99 had undergone, within 1 week of delivery, antenatal Doppler assessment of blood flow in the umbilical artery (UA), fetal middle cerebral artery (MCA), descending aorta (DAo), aortic isthmus and ductus venosus and were eligible for inclusion in the study. Postnatally brain pathology was assessed by serial ultrasound and magnetic resonance imaging in 86 of the neonates and brain volume was measured in 80. Cognitive development was evaluated at 2 years of corrected age in 83 infants using the Bayley Scales of Infant Development-II. Motor development was assessed using the Hammersmith Infant Neurological Examination.


RESULTS
On univariate analysis, abnormal pulsatility index (PI) in the UA and an abnormal UA-PI/MCA-PI ratio (P = 0.04 and P = 0.003, respectively) as well as increases in both the DAo-PI and in the DAo-PI/MCA-PI ratio (P = 0.03 and P = 0.02, respectively), were associated with adverse cognitive outcome at 2 years of age. However, when controlling for cerebral volume using multivariate analysis, the association between abnormal antenatal Doppler characteristics and cognitive outcome became statistically non-significant, which indicated the determinant role of the volume reduction. Motor development was not associated with antenatal Doppler indices.


CONCLUSIONS
Abnormal antenatal Doppler indices are associated with adverse cognitive outcome at 2 years in VLBW infants. Our findings suggest that this association may be mediated through brain volume.
Leppänen
M
M
Department of Pediatrics, Turku University Hospital, Turku, Finland. marika.leppanen@utu.fi
Ekholm
E
E
Palo
P
P
Maunu
J
J
Munck
P
P
Parkkola
R
R
Matomäki
J
J
Lapinleimu
H
H
Haataja
L
L
Lehtonen
L
L
Rautava
P
P
D000293:Adolescent; D000328:Adult; D001783:Blood Flow Velocity / Q000502:physiology; D002657:Child Development / Q000502:physiology*; D002675:Child, Preschool; D003071:Cognition / Q000502:physiology*; D005260:Female; D005317:Fetal Growth Retardation / Q000000981:diagnostic imaging / Q000503:physiopathology*; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D019102:Infant, Very Low Birth Weight; D008297:Male; D009483:Neuropsychological Tests; D010920:Placenta / Q000098:blood supply* / Q000000981:diagnostic imaging; D011247:Pregnancy; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal; D014469:Umbilical Arteries / Q000000981:diagnostic imaging* / Q000503:physiopathology; D055815:Young Adult