Saffron supplementation for ABCA4-related Stargardt Macular Dystrophy: A Short-term Study Evaluating Central Retinal Function

Abstract

 

Purpose

 

<br /> Oxidative damage, as a consequence of ABCA4 gene mutation, has been implicated as a major underlying mechanism for Stargardt disease/fundus flavimaculatus (STD/FF). Recent findings indicate that Saffron (S) carotenoid constituents crocin and crocetin may counteract retinal oxidative damage and protect retinal cells from apoptosis. The aim of this pilot study was to evaluate central retinal function following S supplementation in STG/FF patients carrying ABCA4 mutations.

 

Methods

 

<br /> In a randomized, double-blind, placebo-controlled study (clinicaltrials.gov: NCT01278277), 31 patients with ABCA4-related STD/FF and a visual acuity >0.25 were randomly assigned to assume oral S (20 mg) or placebo (P) over a six month period, and then reverted to P or S for a further six month period. Full ophthalmic examination as well as central 18° focal electroretinogram (fERG) recordings were performed at baseline and after six months of either S or P. The fERG fundamental harmonic component was measured, and its intra-test variability (ITV) and signal-to-noise ratio (S/N) were assessed. Main outcome measures were fERG amplitude (in µV) and phase (in degrees). Secondary outcome measures were fERG ITV and S/N as well as visual acuity.

 

Results

 

<br /> Supplement was well tolerated by all patients throughout follow-up. After S, fERG amplitude and S/N were unchanged; after P, both amplitude and S/N decreased from baseline (mean change: - 0.18 log µV, p < 0.05). Reverting the treatments, amplitude and S/N did not change significantly. fERG phase, ITV and visual acuity were unchanged throughout follow-up.

 

Conclusions

 

<br /> Short-term S supplementation was well tolerated and had no detrimental effects on the electoretinographic responses of the central retina. The current findings warrant further long term clinical trials to assess the efficacy of S supplementation in slowing down the progression of central retinal dysfunction in ABCA4-related STD/FF.