Motor outcomes and visual function in adults born preterm with very low birthweight

Aim To examine whether being born preterm (<37 weeks' gestation) with very low birthweight (VLBW ≤1500 g) is associated with poorer outcomes in mid‐adulthood, and whether this association is mediated by visual function. Method In two prospective cohorts from Finland and Norway, motor outcomes and visual function were assessed in 118 adults born with VLBW and 147 term‐born control individuals. Risk differences (95% confidence intervals [CI]) were assessed for overall and gross motor difficulties (<5th centile on Bruininks Motor Ability Test Short Form and Revised High‐level Mobility Assessment Tool) and fine motor difficulties (>2 standard deviations on the Grooved Pegboard and Trail Making Test‐5). We investigated the association between VLBW and motor outcomes with best‐corrected visual acuity (BCVA) as mediator. Results Overall motor difficulties were present in 34.7% of the VLBW and 4.8% of the control groups (risk difference 29.9%; 95% CI 20.6–39.1). Risk differences were 2.6% (−1.1 to 6.2) to 12.3% (4.9–19.7) for fine motor difficulties and 15.5% (7.5–23.6) for gross motor difficulties. BCVA mediated the association between VLBW and fine motor difficulties as well as continuous overall, fine, and gross motor scores. Interpretation Whether the findings reflect a causal pathway between visual function and motor outcomes, or a shared aetiology, cannot be answered in this study.