Visuospatial outcomes of a prospective national cohort of young adults with very low birthweight

Abstract

Visuospatial processing is reportedly impaired in children born very preterm (VP) compared with full term (FT) controls but there are few data for VP adults. At 26-30 years, 225 very low birthweight (VLBW) adults (70% national cohort survivors) and 100 FT controls were assessed on motor-dependent visuospatial skills using the Block Design subtest of the Wechsler Adult Intelligence Scale, and nonmotor-dependent skills by the Benton Judgment of Line Orientation and Brixton Spatial Anticipation tests. A composite score was created by summing standardized scores for the three tests. MRI measures of cortical volume, thickness and surface area were obtained for 150 VLBW participants. VLBW born adults performed less well than controls across all visuospatial measures and their composite score (P < 0.001), with moderate to large effect sizes (Cohen’s ds = 0.41–0.82). Between group differences were not explained by current vision impairment, cerebral palsy, sex, ethnicity or socio-demographic factors. The unadjusted visuospatial composite score was significantly correlated with reduced cortical surface area and cortical volume, but few correlations remained significant after adjustment for age, sex and intracranial volume. The visuospatial functioning of adults born VLBW is significantly poorer than their FT peers with only modest associations with cortical brain structure.