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Abstract

Dagnelie, Zorge and McDonald, Johns Hopkins University School of Medicine, Baltimore, Maryland, USA. examined the effects of lutein supplementation on visual acuity, central visual-field area, and subjective visual disturbances in retinitis pigmentosa (RP) and related retinal degenerations.

Background

Methodology

An international study population was recruited via an Internet mailing list. Sixteen participants (13 with RP, three with other retinal degenerations) completed a 26-week program of lutein supplementation (40 mg/day for 9 weeks, 20 mg/day thereafter); 10 participants also took 500-mg docosahexaenoic acid (DHA)/day, vitamin B complex, and digestive enzymes. Ten participants previously taking vitamin A and/or beta-carotene continued those supplements throughout the study. Participants self-tested their visual acuity on their computer screen and their central visual-field extent on a wall chart, weekly for 14 weeks, bi-weekly thereafter.

Results

Mean visual acuity improved by 0.7 dB and mean visual-field area by 0.35 dB. Improvements started 2 to 4 weeks after supplementation began, and plateaued at 6 to 14 weeks. Visual acuity gains were strongly correlated with eye colour: 1.2 dB in seven blue-eyed participants, but 0.3 dB in seven dark-eyed participants. Participants who received previous supplements showed greater benefits in central visual-field area (0.55 dB) than those not receiving previous supplements (no change). No significant effects of age, sex, disease stage, or study supplement were found.

Conclusion

Short-term vision improvements after lutein supplementation, previously reported in age-related macular degeneration, also occur in RP, especially in blue-eyed individuals ; vitamin A may increase visual field benefits.

References

Dagnelie G et al. Lutein improves visual function in some patients with retinal degeneration: a pilot study via the Internet. Optometry 71(3): 147-64. Mar 2000.