Association between small-for-gestational age and neurocognitive impairment at two years of corrected age among infants born at preterm gestational ages: a cohort study

Objective:to investigate the association between small-for-gestational age (sga) and neurocognitive impairment at 2 years of corrected age among infants born at preterm gestational ages.study design:a secondary analysis of a prospectively conducted nichd/maternal-fetal medicine units beam trial. non-anomalous pregnancies delivered before 37 weeks of gestation were included in the analysis. neurocognitive outcomes at 2 years of corrected age were compared between infants who were sga (<10% for gestational age) and those appropriately grown (aga). the primary outcome was a severe or moderate neurocognitive impairment at 2 years of corrected age among survivors, defined as either mental (mdi) or psychomotor (pdi) developmental index score <70 for severe and <85 for moderate impairment.results:of 2299 preterm neonates 67 (3%) were sga. sga infants were more often twin pregnancies (31% vs 17%, p=0.003) and delivered more often by cesarean section (63% vs 40%, p<0.001) at similar gestational ages (30.0±2.6 vs 29.5±2.8 weeks, p=0.11). at 2 years of corrected age, sga and aga survivors had similar rates of neurocognitive impairment (mdi <70: 18% vs 18%, p=1.0; mdi <85: 44% vs 46%, p=0.96; pdi <70: 20% vs 15%, p=0.51; pdi <85: 40% vs 34%, p=0.48).conclusion:in this cohort, sga at preterm gestational ages was associated with similar rates of neurocognitive impairment at two years of corrected age among surviving infants.