Dietary patterns were not associated with age-related macular degeneration: a cross-sectional analysis in the Irish Nun Eye Study

Background Analysing dietary patterns (DP) evaluates overall dietary intake, taking account of its complexity, quality, variance and the interaction between different foods, providing an alternative approach for the evaluation of nutritional influences on age-related macular degeneration (AMD) risk. Aims To evaluate the relationship between DP and AMD in an older female population. Methods Data was analysed from the cross-sectional Irish Nun Eye Study involving 1233 older women with a restricted lifestyle (mean age 76.3 years [range, 56-100 years). The Wisconsin Age-related Maculopathy Grading System was used to classify digital colour macular fundus images and dietary intake was assessed using a food frequency questionnaire (n=1033). A posteriori DP were derived using principal component analysis. Logistic regression models examined associations between DP and AMD risk with adjustment for confounders. Results Two DP were identified: a 'healthy' pattern characterised by a high intake of oily fish, wholegrains, vegetables and fruit; and an 'unhealthy' pattern characterised by high-fat dairy products, sugar, sweets and chips. Of the participants included within the analysis, AMD status were categorised as controls (n=818, 86.9%), early AMD (n=83, 8.8%) and late AMD (n=21, 2.2%). Regression analysis failed to identify any significant associations between healthy or unhealthy DP and AMD risk, in unadjusted and adjusted models. Conclusion No evidence of an association between the DP identified and AMD risk was detected in this well-characterised population. Further research is required to determine the overall dietary influences on AMD risk in general population cohorts.