HEALTH NEWS

Study Title:

DHA Intake and Risk for Age-Related Macular Degeneration

Study Abstract

Objective To examine whether intake of -3 fatty acids and fish affects incidence of age-related macular degeneration (AMD) in women.

Design A detailed food-frequency questionnaire was administered at baseline among 39 876 female health professionals (mean [SD] age: 54.6 [7.0] years). A total of 38 022 women completed the questionnaire and were free of a diagnosis of AMD. The main outcome measure was incident AMD responsible for a reduction in best-corrected visual acuity to 20/30 or worse based on self-report confirmed by medical record review.

Results A total of 235 cases of AMD, most characterized by some combination of drusen and retinal pigment epithelial changes, were confirmed during an average of 10 years of follow-up. Women in the highest tertile of intake for docosahexaenoic acid, compared with those in the lowest, had a multivariate-adjusted relative risk of AMD of 0.62 (95% confidence interval, 0.44-0.87). For eicosapentaenoic acid, women in the highest tertile of intake had a relative risk of 0.66 (95% confidence interval, 0.48-0.92). Consistent with the findings for docosahexaenoic acid and eicosapentaenoic acid, women who consumed 1 or more servings of fish per week, compared with those who consumed less than 1 serving per month, had a relative risk of AMD of 0.58 (95% confidence interval, 0.38-0.87).

Conclusion These prospective data from a large cohort of female health professionals without a diagnosis of AMD at baseline indicate that regular consumption of docosahexaenoic acid and eicosapentaenoic acid and fish was associated with a significantly decreased risk of incident AMD and may be of benefit in primary prevention of AMD.

From press release:

Regular consumption of fish and omega-3 fatty acids found in fish is associated with a significantly reduced risk of developing age-related macular degeneration in women, according to a report posted online that will appear in the June issue of Archives of Ophthalmology, one of the JAMA/Archives journals.

"An estimated nine million U.S. adults aged 40 years and older show signs of age-related macular degeneration (AMD)," the authors write as background information in the article. "An additional 7.3 million persons have early age-related macular degeneration, which is usually associated with moderate or no vision loss but does increase the risk of progression to advanced age-related macular degeneration."

Using the Women's Health Study, William G. Christen, Sc.D., of Brigham and Women's Hospital and Harvard Medical School, Boston, and colleagues collected data on 38,022 women who had not been diagnosed with age-related macular degeneration. Information on women's eating habits was obtained via questionnaire at the beginning of the study and included information on intake of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) [Omega-3 fatty acids found in fish], and arachidonic acid and linoleic acid (omega-6 fatty acids). During ten years of follow-up, additional questionnaires tracked the women's eye health, with specific focus on diagnosis of age-related macular degeneration.

Over the course of follow-up, 235 cases of age-related macular degeneration were reported. In analyses that adjusted for age and treatment assignment, women who consumed the most DHA compared with women who consumed the lowest amount had a 38 percent lower risk of developing age-related macular degeneration. Similar results were observed for higher intake of EPA and for higher consumption of both types of acid together.

Results for fish intake showed that consumption of one or more servings of fish per week, when compared to less than one per month, was associated with a 42 percent lower risk of age-related macular degeneration. "This lower risk appeared to be due primarily to consumption of canned tuna fish and dark-meat fish."

For omega-6 fatty acids, higher intake of linoleic acid but not arachidonic acid was associated with an increased risk of age-related macular degeneration, however this association was non-significant after adjustment for other risk factors and fats.

"In summary, these prospective data from a large population of women with no prior diagnosis of AMD indicate that regular consumption of DHA and EPA and fish significantly reduced the risk of incident AMD," the authors conclude.

Study Information

William G. Christen; Debra A. Schaumberg; Robert J. Glynn; Julie E. Buring
Dietary {omega}-3 Fatty Acid and Fish Intake and Incident Age-Related Macular Degeneration in Women.
Arch Ophthalmol,
2011 March
Brigham and Women's Hospital and Harvard Medical School, Boston.