Visual function in adults born preterm with very low birth weight-A two-country birth cohort study.

Purpose: The purpose of the study was to investigate visual function and vision-related general health in adults that were born preterm with very low birth weight (VLBW: birth weight < 1500 g) in their 30s-40s.

Methods: We recruited 137 adults born preterm with VLBW and 158 term-born controls aged 31-43 years from two birth cohorts: the Helsinki Study of Very Low Birth Weight Adults (Finland) and the NTNU Low Birth Weight in a Lifetime Perspective study (Norway). We used neonatal data and measured refraction, best-corrected visual acuity (BCVA) using the Early Treatment Diabetic Retinopathy Study (ETDRS) chart, contrast sensitivity, visual fields, intraocular pressure (IOP), self-reported vision-targeted health status with the National Eye Institute Visual Function Questionnaire-25.

Results: VLBW adults had a lower BCVA ETDRS score than controls: mean (SD) better eye 86.7 (13.4) versus 90.2 (4.4), p = 0.02; mean (SD) worse eye 82.3 (14.9) versus 87.6 (4.6), p = 0.003. VLBW adults also had lower contrast sensitivity thresholds in several spatial frequencies and scored lower than controls in eight out of the 12 subscales of self-reported vision-targeted health status. Refraction, visual fields and IOP were similar between groups. Two VLBW participants were blind. None had been treated for retinopathy of prematurity.

Conclusion: We suggest that lower visual function and vision-related health represent life-long consequences of prematurity and VLBW in the studied 31- to 43-year-old cohort. The underlying mechanisms remain to be determined.