Babies' Vision Improves With Fatty Acid Formula Supplements

Yael Waknine

December 18, 2012

Fatty acid supplementation of infant formula can improve babies' vision, according to a review article published online December 17 in Pediatrics.

Analyzing data from 19 studies involving 1949 infants, Ahmad Qawasmi, MD, from the Department of Pediatrics at the Children's Hospital of Michigan in Detroit, and colleagues found that long-chain polyunsaturated fatty acid (LCPUFA) supplementation started within 1 month of birth significantly improved infants' visual acuity at 2, 4, and 12 months of age, as assessed using visual evoked potential (VEP), and at 2 months when measured using behavioral methods (BM).

According to the authors, the findings stand in contrast to 2 recently published Cochrane systematic reviews that failed to show similar benefit for LCPUFA supplementation.

"These meta-analyses failed to combine trials that (1) measured visual acuity in logMAR and cycles/degree and (2) assessed preterm and term infants separately," the authors explain, noting that these decisions substantially reduced the studies' power to detect supplementation benefits.

Moreover, the visual benefits of LCPUFA supplementation are in line with scientific evidence.

As previously reported by Medscape Medical News, LCPUFAs are made available to infants primarily via breast milk and play essential roles in their growth and development.

"[R]etinal cells have the highest concentration of [docosahexaenoic acid] in the human body," the authors write, noting that the fatty acid is necessary not only for optimal retinal function but also for the proper function of the visual processing centers, optic tract, and optic nerve.

Secondary findings of the review suggest that infants benefit from LCPUFA supplementation irrespective of dose, timing (within 1 month of birth), or preterm birth status.

According to Robert W. Arnold, MD, who was not involved in the study, the results are also in line with his own research findings.

Diet Matters

"In the mid '90s we noticed an increased prevalence of retinopathy of prematurity in Alaska Natives — a fact that has been borne up from further study," Dr. Arnold told Medscape Medical News in an interview, describing a study conducted with his own group.

"We suspected some influence of maternal diet," Dr. Arnold said, noting that at the time, omega-3 fatty acid supplementation had been shown to improve early vision, with benefits topping out by 1 year.

"It turned out that diet was not much different for early-term moms in various parts of Alaska during our study. My conclusion? Diet matters in infants. So does love," said Dr. Arnold.

Dr. Arnold is a pediatric ophthalmologist in private practice in Anchorage, Alaska, and also serves as a spokesperson for the American Association for Pediatric Ophthalmology and Strabismus.

For the study, researchers analyzed data from 19 published randomized controlled trials and meta-analyses of studies assessing the relationship between LCPUFA-supplemented and unsupplemented formula (started within 1 month of birth) and visual acuity measured at 2, 4, and/or 12 months, using VEP or BM.

Data from 10 trials of 852 infants evaluated using VEP revealed that LCPUFA-supplemented formula significantly improved resolution acuity at all 3 points, including 2 months (weighted mean difference [WMD], −0.08; 95% confidence interval [CI], −0.14 to −0.03; z, 2.82; P = .005), 4 months (WMD, −0.07; 95% CI, −0.13 to −0.02; z, 2.77; P = .006), and 1 year (WMD, −0.11; 95% CI, −0.20 to −0.03; z, 2.61; P = .009).

When visual acuity was measured using behavioral methods (12 trials, 1095 infants), the meta-analysis demonstrated a significant benefit for LCPUFA supplementation at 2 months (WMD, −0.08; 95% CI, −0.14 to −0.02; z, 2.68; P = .007) but not at 4 months (WMD, −0.01; 95% CI, −0.04 to 0.02; z, 0.77; P = .44) or 1 year (WMD, 0.01; 95% CI, −0.02 to 0.03; z, 0.53; P = .60). Significant heterogeneity between studies was observed only at age 2 months.

Although there was significant heterogeneity between studies at all times showing significant benefit for LCPUFA supplementation, funnel plots demonstrated no evidence of publication bias and meta-regression showed no significant association between sample size and measured study effect.

Although stratified subgroup analysis was only performed with 4-month data from VEP trials, results showed no significant difference in LCPUFA-associated visual benefits between preterm and full-term infants (P = .53).

Regression analyses revealed that benefits were not affected by LCPUFA dose and start time for supplementation (any time within the first month of life was good).

LCPUFA Formula Readily Available

"The fact that LCPUFA-supplemented infant formulas are readily available in markets, the safety profile, and to some extent the beneficial effect of LCPUFAs make them a good supplemental choice to be added to formulas for the optimum well-being of our kids," Dr. Qawasmi told Medscape Medical News, noting that further research and literature analyses are needed to determine whether the visual benefits observed in the review extend beyond the first year of life.

The study was funded by the National Institutes of Health. One coauthor was supported by a National Institutes of Health grant, an American Psychiatric Institute on Research and Education/Eli Lilly psychiatric research fellowship, an American Academy of Child and Adolescent Psychiatry/Eli Lilly junior investigator award, the Trichotillomania Learning Center, NARSAD, and a National Center for Research Resources grant. The other authors and commentators have disclosed no relevant financial relationships.

Pediatrics. Published online December 17, 2012. Abstract