Tuesday, March 29, 2011
omega-3 macula degeneratie
March 21, 2011 — Regular consumption of fish and omega-3 fatty acids is associated with a significantly reduced risk for the development of age-related macular degeneration (AMD) in women, according to the results of a study reported online March 14 in the Archives of Ophthalmology.
"An estimated nine million U.S. adults aged 40 years and older show signs of ...AMD," write William G. Christen, ScD, from Brigham and Women's Hospital and Harvard Medical School in Boston, Massachusetts, and colleagues. "An additional 7.3 million persons have early AMD, which is usually associated with moderate or no vision loss but does increase the risk of progression to advanced AMD .... Dietary intake of fish, and specifically omega-3 fatty acids concentrated in fish (docosahexaenoic acid [DHA] and eicosapentaenoic acid [EPA]), has been linked with reduced rates of cardiovascular events in epidemiologic studies and could have a similar beneficial effect in AMD."
The goal of the study was to evaluate the association of omega-3 fatty acid and fish consumption with incidence of AMD in women. Of 39,876 female health professionals (mean age, 54.6 ± 7.0 years) enrolled in the Women's Health Study, 38,022 women without a diagnosis of AMD completed a detailed food-frequency questionnaire at baseline. The primary endpoint was incident AMD causing a reduction in best-corrected visual acuity to 20/30 or worse, as identified by self-report and confirmed by medical record review.
During follow-up of average duration 10 years, there were 235 confirmed cases of AMD, most of which were characterized by some combination of drusen and retinal pigment epithelial changes.
Compared with women in the lowest tertile of DHA intake, those in the highest tertile had a multivariate-adjusted relative risk (RR) for AMD of 0.62 (95% confidence interval [CI], 0.44 - 0.87). Women in the highest vs the lowest tertile of EPA intake had an RR of 0.66 (95% CI, 0.48 - 0.92).
As would be expected from these findings, the RR for AMD was 0.58 (95% CI, 0.38 - 0.87) for women who consumed at least 1 serving of fish per week vs those who consumed less than 1 serving per month. This lower risk appeared to be mostly attributed to consumption of canned tuna fish and dark-meat fish, such as mackerel, salmon, sardines, bluefish, and swordfish.
"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," the study authors write.
Limitations of this study include lack of generalizability to populations other than female health professionals, reliance on participant self-report, and possible surveillance bias.
"These data appear to be the strongest evidence to date to support a role for omega-3 long-chain fatty acids in the primary prevention of AMD, and perhaps a reduction in the number of persons who ultimately have advanced AMD, and need to be confirmed in randomized trials."
The National Institutes of Health supported this study. Bayer Healthcare and the Natural Source Vitamin E Association provided pills and packaging.
Arch Ophthalmol. Published online March 14, 2011. Full text
