Dietary Nutrient Intake Linked to Slower Geographic Atrophy Progression

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A higher dietary intake of multiple specific nutrients was strongly associated with a reduction in the progression of geographic atrophy (GA) towards the central macula, according to new data presented at the 2024 Association for Research in Vision and Ophthalmology (ARVO).¹

The identified nutrients, including lutein/zeaxanthin, β-carotene, zinc, and omega-3 fatty acids, could be instrumental in the natural phenomenon of relative foveal sparing in GA. As a result, this phenomenon may be altered by a higher dietary intake of these nutrients.

“Patients with non-central GA may benefit from dietary advice targeted towards these specific nutrients, above and beyond general advice on the adoption of a healthy diet,” wrote the investigative team, led by Elvira Agron, MS, DECA, National Eye Institute.

A higher consumption of multiple nutrients, including vitamins, minerals, carotenoids, and fatty acids, has previously been linked to a decrease in the progression of late age-related macular degeneration, particularly GA.²

For the analysis, Agron and colleagues evaluated the association between dietary intake and the progression rates toward the foveal center point (FCP).¹ Color fundus photographs from the annual visits of participants in the Age-Related Eye Diseases Study (AREDS) with non-central GA underwent reading center grading for GA proximity to the FCP.

The team assessed the dietary nutrient intake and the alternative Mediterranean diet index using food frequency questionnaires — nine nutrients were analyzed in the assessment. The alternative Mediterranean diet index was calculated from the intake of these nine components.

Mixed-model regressions were performed with GA proximity as the outcome and nutrient intake, of the 9 components, as the exposure. Relevant models included age, sex, smoking status, GA proximity at first diagnosis, calorie intake, nutrient tertile (T3, highest intake), year, and interaction of year and nutrient tertile. The eye was the unit of analysis.

A total of 413 eyes with non-central GA from 347 participants comprised comprised the patient population. GA was prevalent in 88 eyes and incident in 326 eyes. Upon analysis, the eyes of participants with the highest intake of these nine nutrients showed significantly slower GA progression.

Specifically, the comparisons between the highest intake and lowest intake cohorts (T3 vs. T1) exhibited significantly slower GA progression towards the FCP per year (µm/y):

• Zinc (34.8 [95% CI, 29.6 - 40.1) vs. 45.5 [95% CI, 39.9 - 51.1]; P = .006)
• Β-carotene (29.8 [95% CI, 24.2 - 35.3] vs. 46.6 [95% CI, 41.3 - 51.9]; P <.0001)
• Lutein/zeaxanthin (32.9 [95% CI, 26.2 - 39.6] vs. 47.5 [95% CI, 42.4 - 52.7]; P = .001)
• EPA (35.5 [95% CI, 29.2 - 41.8] vs. 43.7 [95% CI, 38.8 - 48.6]; P = .05).

Agron and colleagues observed no significance for the alternative Mediterranean diet index—thus a higher adherence to a Mediterranean diet is not strongly associated with a slowing in the progression of GA to the FCP. Moreover, the team indicated a separate analysis found that the same nutrients inhibited GA progression in eyes with prevalent GA, but not those with incident GA.

“When analyzed separately, the same nutrients were associated with a slower rate in the prevalent GA cohort but not in the incident GA cohort,” they wrote.

References

1. _{Agron E, Keenan TDL, Vitale S, Chew EY. Associations between Dietary Nutrient Intake and Geographic Atrophy Progression towards the Central Macula. Poster presented at the Association for Research in Vision and Ophthalmology (ARVO) 2024 Meeting, May 5–9, 2024.}
2. _{Agrón E, Mares J, Clemons TE, et al. Dietary Nutrient Intake and Progression to Late Age-Related Macular Degeneration in the Age-Related Eye Disease Studies 1 and 2. Ophthalmology. 2021;128(3):425-442. doi:10.1016/j.ophtha.2020.08.018}