Intake of Blueberries, Anthocyanins, and Risk of Eye Disease in Women

Abstract

Background: Blueberries and anthocyanins, their key bioactive component, may improve eye health. However, few long-term studies have examined blueberries and anthocyanins with cataract and age-related macular degeneration (AMD).

Objectives: To investigate the prospective association between blueberry and anthocyanin intake with incident cataract, total AMD, and visually significant AMD among middle-aged and older women.

Methods: A total of 36,653 and 35,402 women initially free of AMD and cataract, respectively, aged ≥45 y from the Women's Health Study provided semiquantitative food frequency questionnaire data on blueberry intake categorized as none, 1-3 servings/mo, 1 serving/wk, or ≥2 servings/wk, plus a combined category of ≥1 serving/wk. Total anthocyanin intake and major subclasses were energy-adjusted and categorized into quintiles. Self-reported risk factors of eye disease were adjusted in multivariable hazard ratios (HRs) (95% confidence intervals [CIs]) of confirmed cataract, AMD, and visually significant AMD with mean follow-up of 11 y.

Results: Among the participants, 10.5% consumed ≥1 serving/wk of blueberries, with mean total anthocyanin intake of 11.2 mg/d. Compared to no blueberry intake, women consuming 1-3 servings/mo, 1 serving/wk, and ≥2 servings/wk had corresponding multivariable HRs of total AMD of 0.90 (95% CI: 0.73, 1.11), 0.71 (95% CI: 0.50, 1.00), and 0.36 (95% CI: 0.14, 0.93) (P_trend = 0.011); those consuming ≥1 servings/wk had an HR of 0.68 (95% CI: 0.47, 0.98). A similar magnitude of HRs were found for visually significant AMD (P_trend = 0.012) but not for cataract. There were no significant associations between increasing total anthocyanin quintiles and total and visually significant AMD, but there was a modest inverse association with cataract (P_trend = 0.022), driven by a 10% reduction in cataract in the upper 2 quintiles.

Conclusions: Greater blueberry intake significantly reduced total AMD, but not visually significant AMD or cataract. However, the magnitude of effect for visually significant AMD was similar to total AMD. There was a modest but significant inverse association between dietary anthocyanin intake with cataract but not AMD.

Keywords: age-related macular degeneration; cataract; diet; eye disease; prospective studies; women.