White-matter abnormalities on term MRI predict cognitive problems in very preterm infants

• Editor's Note:  Here is another reason that before going home, many NICU babies have an MRI and a neurologist's input to help predict outcome.  
• In this study, abnormal white matter predicted mildly low verbal IQ (odds ratio, 6.2), performance IQ (6.0), and full-scale IQ (6.3), and the need for special assistance at school (5.9). 
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Qualitative Brain MRI at Term and Cognitive 

Outcomes at 9 Years After Very Preterm Birth

1. Sachiko Iwata, MD^a,^b, 
2. Tomohiko Nakamura, MD, PhD^b, 
3. Eriko Hizume, DOT^c,
4. Hideki Kihara, DPT, PhD^c, 
5. Sachio Takashima, MD, PhD^d, 
6. Toyojiro Matsuishi, MD, PhD^a, and 
7. Osuke Iwata, MD^a,^b

+Author Affiliations

1. ^aCentre for Developmental & Cognitive Neuroscience, Department of Paediatrics and Child Health, Kurume University School of Medicine, Kurume, Fukuoka, Japan;
2. Divisions of ^bNeonatology, and
3. ^cRehabilitation, Nagano Children’s Hospital, Nagano, Japan; and
4. ^dYanagawa Institute for Developmental Disabilities, International University of Health and Welfare, Fukuoka, Japan

ABSTRACT

OBJECTIVE: A prospective study was performed to assess the relationship between the appearance of cerebral MRI at term and the cognitive functioning at 9 years old in very preterm born infants.

METHODS: Seventy-six very preterm born infants (birth weight <1500 g or gestational age ≤32 weeks) obtained cerebral MRI at term-equivalent period, which was assessed by using established composite scores for the white and gray matter; cognitive outcomes at 9 years old were assessed in 60 subjects by using Wechsler Intelligence Scale for Children, Third Edition.

RESULTS: Mildly low scores on the different IQ indices (<85) were observed in 23.3% (verbal IQ), 41.7% (performance IQ), and 30.0% (full-scale IQ) of the cohort, whereas moderately low scores (<70) were noted in 3.3% (verbal IQ), 11.7% (performance IQ), and 11.7% (full-scale IQ); cerebral palsy was diagnosed in 10.0%, whereas special assistance at school was required in 56.7%. Abnormal white matter appearances predicted mildly low verbal, performance, and full-scale IQs; moderately low performance and full-scale IQs; cerebral palsy; and the requirement for special assistance at school. Abnormal white matter appearances predicted mild cognitive impairment even after the adjustment for known clinical risk factors. In contrast, abnormal gray matter appearances did not predict any of the outcome measures.

CONCLUSIONS: In a cohort of very preterm born infants, abnormal white matter appearance on term MRI showed consistent associations with cognitive impairments at 9 years old, further supporting the benefit of obtaining term MRI for very preterm born infants.

Maternal Obesity May Influence Brain Development of Premature Infants

Obesity is a modifiable risk factor that can affect cognition. JR

Maternal Obesity May Influence Brain Development of Premature Infants

ScienceDaily (Mar. 8, 2012) — Maternal obesity may contribute to cognitive impairment in extremely premature babies, according to a new study by researchers at Wake Forest Baptist Medical Center.

"Although in the past decade medical advances have improved the survival rate of babies born at less than seven months, they are still at very high risk for mental developmental delays compared with full-term infants," said Jennifer Helderman, M.D., assistant professor of pediatrics at Wake Forest Baptist and lead author of the study. "This study shows that obesity doesn't just affect the mother's health, but might also affect the development of the baby."

Published in the March issue of the journal Pediatrics, the study looked at 921 infants born before 28 weeks of gestation during 2002 to 2004 at 14 participating institutions. The researchers assessed the babies' placenta for infection and other abnormalities, interviewed the mothers and reviewed their medical records. At age 2, the children's cognitive skills were evaluated using the Mental Development Index (MDI) portion of the Bayley Scales of Infant Development, a commonly used measure.

The scientists found that both maternal obesity and lack of high school education were associated with impaired early cognitive function, as was pre-term thrombosis (blood clot) in the placenta.
"We weren't really surprised by the socioeconomic factors because it has been repeatedly shown that social disadvantage predicts worse infant outcomes," Helderman said. "However, obesity is of particular interest because it is becoming more prevalent and it is potentially modifiable during the pre-conception period and pregnancy."

Obesity has been linked to inflammation, and inflammation can damage the developing brain, Helderman said. What isn't known is if the obesity-related inflammation in the mother is transmitted to the fetus.
"Few studies have addressed prenatal risk factors of cognitive impairment for infants born this prematurely. The long-term goal is to use information from studies like ours to develop treatments that prevent cognitive impairment in extremely premature babies," Helderman said.
Helderman's colleague, Michael O'Shea, M.D., section head of neonatology at Wake Forest Baptist, is currently conducting a study that follows these same babies into mid-childhood to determine long-term cognitive problems.

More than 30,000 extremely premature babies are born each year in the United States.