Autism prodrome 42 of 89
ELBW children to age 8 years and found increased rates of anxiety disorders and
ADHD, as well as elevated rates of ASDs.
Gardner et al. (2008) also report partial data on very early behavior predictors
of ASD in NICU infants. In their longitudinal study, approximately 1.5% of the NICU
infants were eventually diagnosed with ASD, indicating more than a 2-fold risk of
ASD in this sample, with diagnosed ASD children being predominantly male, with
higher-educated mothers, and born at lower gestational age and birth weight. They
reported that ASD children exhibited a pattern of behavioral deficits starting in the
newborn period. Their neonatal neuro-behavior status at 1 month showed higher
incidences of visual asymmetry, increased hypertonicity in arms, and better head
extension compared to a matched comparison group of NICU babies without an
outcome diagnosis of ASD. At 4 months these children had poorer arousal modulation
of visual attention which was exhibited by showing greater stimulus seeking. As early
as 7 and 10 months, their Bayley-II motor and mental scores were lower than those of
the comparison group. The authors suggested that infants who are later diagnosed
with ASD might form a distinct sub-population within NICU-assigned babies,
characterized with atypical development of visual, motor, and regulatory processes
which could be identified from the early neonatal period, and that these differences
might be indicative of precursors to ASD at older ages.
Given the abovementioned findings it appears that it may be important for
researchers involved in prospective studies of at risk samples to collect data regarding
pre-, peri-, and post-natal development - using both parental report and where
possible medical records - and to explore possible associations among these data and
the developmental trajectories associated with the prodrome/s of ASDs.
Genetics as a risk factor in ASD