Visual function is reduced in young adults formerly born prematurely: a population-based study

AIMS: To assess visual function in young adults born preterm and compare with full-term individuals of the same age. METHODS: Young adults, born preterm (birth weight ≤1500 g) in 1988–1990, previously included in a population-based study on the incidence of retinopathy of prematurity (ROP) in Stockholm County, Sweden were included. A control group of participants born at term, in the same area during the same time period, was used for comparison. Best-corrected visual acuities were assessed at distance and near with logMAR charts. Distance visual acuity was also measured with single symbols to calculate crowding. Visual fields were measured with Humphrey 24-2 and the mean deviation was noted. Contrast sensitivity was assessed with Vistech contrast sensitivity test and the area under the curve was calculated. RESULTS: Fifty-nine preterm (females 37) and 44 full-term (females 18) individuals were included. All individuals were between 25 and 29 years of age. Preterm individuals had significantly lower distance visual acuity (mean −0.08 (SD 0.11) vs −0.14 (SD 0.07) logMAR, p=0.009), near visual acuity (mean −0.08 (SD 0.11) vs −0.13 (SD 0.06) logMAR, p=0.049), mean deviation (mean −1.09 (SD 1.13) vs −0.80 (SD 1.03) dB, p=0.05) and contrast sensitivity (mean 2.02 (SD 0.19) vs 2.16 (SD 0.14), p<0.001) in the better eye compared with full-term individuals. The differences in distance visual acuity and contrast sensitivity were also evident after excluding persons with previous ROP and neurological complications. In multivariable analyses, treated ROP was a risk factor for reduced near visual acuity and visual fields. CONCLUSION: Visual function seems to be reduced in prematurely born individuals even in adulthood. The reason may be prematurity per se since individuals without previous ROP or neurological complications are also affected. SYNOPSIS: Visual function, assessed as visual acuity, visual fields and contrast sensitivity, was reduced in young adults born preterm and previously included in a population-based study on the incidence of retinopathy of prematurity, as compared with controls.