A randomized, placebo-controlled clinical trial of docosahexaenoic acid supplementation for X-linked retinitis pigmentosa

Effectiveness and safety of nutritional supplements in the treatment of hereditary retinal dystrophies: a systematic review

“…Finally, 8 studies informed in 13 articles were included in the present review. [9][10][11][12][13][14][15][16][17][18][19][20][21] Characteristics of studies…”

“…12 Except Lee et al which studied Best disease, 18 all included studies are on RP. [9][10][11][12][13][14][15][16][17][19][20][21] They assessed supplements based on vitamin A and vitamin E, 12 docosahexaenoic acid (DHA), 9,10,14,16,18 and the carotenoids lutein, 11,13 and β-carotene. 19 We did not identify eligible studies about other HRDs.…”

“…In addition, both trials of Hoffman et al did not find any significant mean difference in visual acuity between DHA and placebo groups during a 4 years follow-up period. 9,10,16 Regarding studies on lutein supplementation, Berson et al did not find additional effect of this carotenoid in the annual decline of ETDRS letters in a population supplemented with vitamin A. 13 Bahrami et al found a statistically significant improvement (P = 0.018) of visual acuity related to lutein when measured in very low illumination conditions (0.1%), but not in normal (100%) or low (4%) illumination conditions.…”

“…14 However, in a subsequent subgroup analysis which included only patients who were not receiving vitamin A before the trial onset (n = 208), they found significant differences in the decline of central and total visual field sensitivity for the group that received DHA plus vitamin A (P = 0.01), although the difference only occurred in the first 2 years of this 4-year study. 15 Finally, Hoffman et al 16 found no statistically significant differences between groups in the mean visual field defect after four years (DHA group 2.4 ± 3.66 dB, versus placebo group 1.4 ± 1.32 dB, P = 0.29). 16 However, a recent ancillary analysis 10 of Hoffman 9 shows that supplementation of DHA significantly slowed visual field sensitivity loss as compared with placebo (Po 0.0001).…”

“…14 Hoffman et al evaluated the effect of DHA in males, as they only studied an X-linked RP which manifests mainly, but not exclusively, in men. 16 In a subsequent trial by the same group, DHA dose was adapted to each participant's weight and a multivitamins supplementation providing 100% of recommended daily amounts of vitamins A, C, D, E, B6, and B12 was added to both groups. 9 Bahrami et al 11 and Berson et al 13 studied supplementation with lutein in patients with different follow-up periods of 48 weeks and 4 years, respectively.…”