Dietary profile and vitamin A intake in patients with Stargardt Disease and Retinitis Pigmentosa

Abstract

Purpose: Stargardt Diasease (STGD) and Retinits Pigmentosa (RP) are genetic-based relevant ocular diseases which may be affected, in opposite way, by vitamin A intake. Indeed, for STGD patients, the vitamin A intake from diet is recommended to be as low as possible while, in RP patients, vitamin A is usually recommended to be supplemented. Despite these clinical indications, however, no data on nutritional habits of these patients are available. The purpose of this study was to evaluate the dietary habits and nutritional intake of vitamin A in patients with STGD and of RP, in order to seek for possible dietary modifications.

Methods: Dietary habits, vitamin A intake and clinical evaluations were performed in 24 patients with STGD [12 M, 12 F; median age: 34 years (range: 13-64)], and in 56 patients with RP [23 M, 33 F; median age: 45 years (range: 14-85)].

Results: The median intake of vitamin A was 771.1 (range: 266.2-3863.2) mg/day in STGD patients and 871.2 (146.8-7935.8) mg/day in RP patients. According to the recommended daily intake guidelines for the Italian population, we documented in only 6 out of 24 (25%) STGD patients a daily intake of vitamin A within the recommended range (600-700 mg/day) while 14/24 (58.3%) reported a high daily intake (>700 mg/day). With regard to RP, 4/56 (7.1%) reported to be within the recommended range and 37/56 (66.1%) were above the recommended daily intake. Interestingly, STGD patients with low vitamin A intake (<600 mg/day) showed significantly better visual acuity (right eye: 6.8 ± 3.4; left eye: 7.0 ± 3.8 vs. 3.2 ± 2.8 and 3.2 ± 2.7; p=0.04) with respect to those introducing higher intake of vitamin A (>600 mg/day). On the other hand, RP patients with high vitamin A intake (>700 mg/day) showed a higher, albeit not significant, age of onset of the disease (30.8 ± 5.7 years) vs. those reporting low vitamin A intake (25.5 ± 9.0 years).

Conclusions: Our data reported that, despite information on the importance of diet and vitamin A intake, a high proportion of patients with STGD and RP do not follow recommendations for daily intake of vitamin A through the diet. These preliminary data suggest a need of nutritional screening in STGD and RP patients.

Keywords: 761 vitamin A deficiency • 688 retina • 696 retinal degenerations: hereditary