Relationship between Dietary Fat and Age–related Maculopathy in the Carotenoids in Age–Related Eye Disease Study (CAREDS), an ancillary study of the Women's Health Initiative.

Abstract

Abstract: : Background:Dietary fat may be involved in the pathogenesis of age–related maculopathy (ARM) via several pathways. Evidence for associations between dietary fat and ARM is inconsistent in epidemiological studies. Purpose:To describe the relationship between the amount and specific type of dietary fat intake with early lesions of ARM. Methods: Dietary intake of postmenopausal women aged 50–79 years was estimated at the time of enrollment (baseline) into the Women’s Health Initiative (WHI) observational study in 1994–1998 using a food frequency questionnaire. A subset of these women with intakes of lutein above the 78^th and below the 23^rd percentiles was invited to participate in the Carotenoids in Age Related Eye Disease Study (CAREDS) in 2001–2003. Analyses were done in a preliminary dataset (N=1512). ARM was assessed from stereoscopic fundus photographs. Results: Levels of total fat intake were not associated with development of early ARM lesions. The odds ratio (OR) for early ARM, adjusted for age, smoking, lutein intake, hormone use, family history of ARM and highdose antioxidant supplement use for over 10 years, in the highest quintile of total fat intake ( % energy) was 0.9 (95% CI: 0.6, 1.4; p for trend: 0.88) compared to the lowest quintile of fat intake. Polyunsaturated fats (PUFA) in the highest compared to the lowest quintile of intake measured as % of energy, increased risk for drusen (adjusted OR: 3.0; 95% CI: 1.4, 6.2; p for trend: 0.02). Associations of PUFA with pigmentary abnormalities (PA) and early ARM were in the same direction as drusen, but not statistically significant. Saturated fat (SFA) intake was directly but non–significantly associated with early lesions. Higher intake (% energy) of monounsaturated fats (MUFA) reduced the odds for drusen (adjusted OR: 0.4; 95% CI: 0.14, 1.1; p for trend: 0.7), PA (adjusted OR: 0.4; 95% CI: 0.1, 1.4; p for trend: 0.2) and any early ARM (adjusted OR: 0.4; 95% CI: 0.2, 0.98; p for trend: 0.06). Levels of long–chain omega–3 fatty acid intake were not associated with early ARM. Conclusions:Total dietary fat intake was not associated with early ARM. However, type of dietary fat influenced risk of ARM: PUFA increased risk of drusen, pigmentary abnormalities and retinal pigment abnormalities while MUFA was protective against these lesions. In sum, high PUFA and low MUFA intake were associated with ARM.

Keywords: age–related macular degeneration • nutritional factors • clinical (human) or epidemiologic studies: risk factor assessment