Associations between Dietary Intake of Lutein and Diabetic Retinopathy in the Atherosclerosis Risk in Communities (ARIC) Study

Abstract

Purpose: Lutein may protect against diabetic retinopathy (DR) due to its ability to absorb oxidizing blue light, its antioxidant properties and its location within the retina. Data from animal models and small studies conducted in humans (N<150) suggest that lutein may be inversely associated with DR. We hypothesized that dietary intake of lutein is inversely associated with DR and examined this association in the biracial ARIC cohort.

Methods: We tested our hypothesis by analyzing data collected from 1,430 study participants with diabetes (n=957 White and n=473 Black). We used logistic regression to calculate crude and adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for prevalent DR by quartile (Q) of energy-adjusted lutein intake. DR was assessed using a 45-degree nonmydriatic retinal photograph from one randomly chosen eye taken at visit 3 (1993-95). Dietary lutein intake was estimated using an interviewer administered 66-item food frequency questionnaire at visit 1(1987-89).

Results: The median estimated daily lutein intake was 1370 (interquartile range 723 - 2627) µg/1000 kcals and the prevalence of DR was 21%. We found a crude association between lutein and prevalent DR [OR (95% CI) for Q4 (high intake) vs. Q1 (low intake) =2.12 (1.45 - 3.10); p for trend=0.0003]. This association was attenuated after adjustment for race, duration of diabetes, glycated hemoglobin levels, field center and energy intake [1.40 (0.86 - 2.27); p for trend=0.23]. Associations were similar when the analyses were stratified by race but the association was stronger in Blacks [2.29 (0.53 - 9.88); p for trend=0.53]. In analyses limited to people with a short duration of diabetes (<6 years), the association between lutein and DR no longer persisted [0.94 (0.33-2.65); p for trend=0.99] as compared to the association in those with a longer duration of diabetes (≥6 year) [1.54 (0.88-2.70); p for trend=0.24] We found no evidence of multiplicative interaction between lutein and duration of diabetes (p for interaction = 0.70).

Conclusions: Contrary to our hypothesis, we found that the odds of higher lutein intake were greater among those with DR than those without DR. However, after adjusting for confounders, intake of lutein was not associated with DR. This was a secondary data analysis and further investigation of this finding using data collected for this purpose is needed.

Keywords: 499 diabetic retinopathy • 618 nutritional factors • 444 carotenoids/carotenoid binding proteins