Perinatal characteristics may influence the outcome of visual acuity

Visual-evoked potential (VEP) acuity has been used to assess the effects of dietary fats on the integrity of the visual pathway of infants. We investi gated prognostic determinants of VEP acuity at 16 wk of age. The results of two randomized dietary intervention trials designed to assess the effect o f dietary fatty acids on the visual development of term infants were combin ed. At entry to both trials (similar to day 5 of life), a blood sample to a ssess polyunsaturated fatty acid (PUFA) status was collected along with soc iodemographic and perinatal characteristics. At 16 +/- 0.9 wk of age, infan ts underwent VEP testing to measure acuity. There was no effect of dietary treatment on these outcomes within or between trials. Multiple linear regre ssion models were constructed to investigate the effect of perinatal and nu tritional variables at study entry on VEP acuity of 185 infants. Higher bir th weight was associated with an ability to resolve smaller checkerboard pa tterns [r(2) = 0.05; 95% confidence interval (CI), -0.10, -0.04 log units]. Male gender (r(2) = 0.03; 95% CI, 0.01, 0.07 log units), day 5 plasma 22:5 n-6 (r(2) = 0.04; 95% Cl, 0.02, 0.20 log units), day 5 red cell membrane 20 :3n-9 (r(2) = 0.05; 95% CI, 0.03, 0.13 log units), and the number of smoker s in the household (r(2) = 0.02; 95% CI, 0.00, 0.04 log units) were all ass ociated with poorer VEP acuity scores. It is possible that a combination of perinatal factors could accumulate to either mask or enhance effects of di et on VEP acuity, given the relatively modest effects of long-chain PUFA on visual outcome.