Low Dose Oral Vitamin A Supplementation may effect improvement in AMD

Kristina Pfau and colleagues undertook a study in understanding the impact of oral vitamin A supplementation on patients with intermediate age-related macular degeneration (AMD). In a recent study published in Retina Journal 16,000 IU of vitamin A administration appears to offer partial alleviation of the pathophysiological functional alterations observed in AMD-afflicted eyes.

The study involved a group of twelve participants divided into two categories: those with AMD but without reticular pseudodrusen (AMD group) and those with AMD and reticular pseudodrusen (RPD group). The AMD group consisted of five individuals with a mean age of 78.0 years, while the RPD group included seven individuals with an average age of 74.1 years. Over the course of 8 weeks, both groups were administered a daily dose of 16,000 IU of vitamin A palmitate.

The results of this study were nothing short of remarkable. In the AMD group, there were significant improvements in several key parameters related to vision and macular health. Rod intercept time, a crucial measure of dark adaptation, showed a noteworthy improvement of -1.1 minutes after 4 weeks and an even more substantial improvement of -2.2 minutes after 8 weeks of vitamin A supplementation.

Furthermore, the dark adaptation cone plateau, which indicates cone threshold sensitivity, also improved significantly at both 4 and 8 weeks into the study.

However, it's important to note that no significant improvements were observed in any parameter for the RPD group, despite elevated serum vitamin A levels in both groups following supplementation.

This study underscores the potential benefits of oral vitamin A supplementation for individuals with intermediate AMD. Notably, the dose used in this study, 16,000 IU, was lower than in previous research, suggesting that even a relatively moderate supplementation regimen can lead to significant improvements in AMD-related functional changes.

However, the lack of improvement in the RPD group raises intriguing questions. It could suggest that there are structural obstacles hindering the absorption or utilization of vitamin A in these patients. Alternatively, it might reflect the higher variability in functional parameters observed in this subgroup.

Source: 

Pfau, K., Jeffrey, B. G., & Cukras, C. A. (2023). LOW-DOSE SUPPLEMENTATION WITH RETINOL IMPROVES RETINAL FUNCTION IN EYES WITH AGE-RELATED MACULAR DEGENERATION BUT WITHOUT RETICULAR PSEUDODRUSEN. In Retina (Vol. 43, Issue 9, pp. 1462–1471). Ovid Technologies (Wolters Kluwer Health). https://doi.org/10.1097/iae.0000000000003840