The effect of socioeconomic status on the language outcome of preterm infants at toddler age

Background

Independently, both prematurity and low socioeconomic status (SES) compromise language outcome but less is known regarding the effects of low SES on outcome of prior preterm infants at toddler age.

Aim

To assess SES effects on the language outcome of prior preterm infants at toddler age.

Study design

Retrospective chart review of infants born at ≤ 32 weeks, matched for gestational age (GA), birth weight (BW), chronic lung disease (CLD), periventricular leukomalacia (PVL), right and left intraventricular hemorrhage (IVH-R, L), and age at Bayley Scales of Infant Development III (BSID-III) testing.

Subjects

Using insurance status as a proxy for SES, 65 children with private insurance (P-Ins) were matched with 65 children with Medicaid-type insurance (M-Ins).

Outcome measures

Bayley Scales of Infant Development-III Language Composite.

Results

M-Ins vs. P-Ins were similar in GA, BW, and age at BSID-III testing (mean 22.6 months adjusted), as well as other matched characteristics (all p ≥ 0.16). BSID-III Language Composite scores were lower in M-Ins than P-Ins (87.9 ± 11.3 vs. 101.9 ± 13.6) with a clinically significant effect size of 0.93 (p < 0.001). Overall, 45% of M-Ins exhibited mild to moderate language delay compared to 8% of P-Ins. Receptive and Expressive subscale scores also were lower in M-Ins than in P-Ins (both p < 0.001).

Conclusions

In this preterm cohort, by toddler age, M-Ins was associated with lower scores on measures of overall language as well as receptive and expressive language skills. Our findings, showing such an early influence of SES on language outcome in a cohort matched for biomedical risk, suggest that very early language interventions may be especially important for low SES preterm toddlers.