Factors affecting neurodevelopmental outcome at 2 years in very preterm infants below 1250 grams: a prospective study

To evaluate the neurodevelopmental outcomes of preterm very-low birth weight (PT/VLBW) infants at 2 years and identify risk factors associated with significant developmental delay or neurodevelopmental impairment (NDI).

We evaluated 165 PT/VLBW infants born between January 2010 and December 2011, using the Bayley Scales of Infant and Toddler Development 3rd Edition (Bayley-III). NDI was defined as the presence of neurosensory impairment or significant delay with Bayley-III score < 70 in any domain and risk factors for delay/NDI were assessed using logistic regressions.

Median Bayley-III composite scores in the cognitive, language and motor domains were 95, 89 and 94, respectively. NDI was present in 20% of the children, with 5-18% having significant delay in either cognitive, language or motor domain, seven (4%) children had cerebral palsy, three (2%) were deaf and none were blind. Regression models identified significant positive associations of delayed cognitive skills with male gender (Odds ratio (OR) 22.4, 95% confidence interval (CI) 1.5-341.1; P = 0.025), lack of anntenatal steroids (ANS) (OR 41.5, 95% CI 3.5-485.7; P = 0.003), and hypotension needing inotropes (OR 36.0, 95% CI 2.6-506.0; P = 0.008); delayed language skills with lower maternal education (OR 3.8, 95% CI 1.4-10.3; P = 0.10), lack of ANS (OR 2.8, 95% CI 1.1-7.4; P = 0.04), and 5 minute Apgar Score ≤ 5 (OR 7.4, 95% CI 1.4-38.4; P = 0.017) and delayed motor skills with chronic lung disease at 36 weeks (OR 38.3, 95% CI 2.4-603.4; P = 0.010). NDI was associated with lack of ANS (OR 2.91, 95% CI 1.21-7.00; P = 0.02) and use of postnatal steroids (OR 3.36, 95% CI 1.07-10.54; P = 0.0374).

Risk factors for both NDI and individual domain delay were identified and will be helpful in planning of specific and targeted early intervention services.