Unfortunately the commonest single underlying factor is AGE- sadly we can’t do too much about ageing, but it is now becoming increasingly recognised that some other factors may well be playing a role in the development of AMD – and these may well be modifiable.
A newly released report -as part of the CAREDS study examined the risk of AMD among women aged between 50 to 79 years. This was an ancillary investigation of the much larger Women’s Health Initiative, an observational study that has tracked the health-related behaviours and outcomes of more than 160,000 women since 1991.
The researchers evaluated the diet and exercise patterns of 1,663 women and categorised them into lowest-, moderate- and highest-risk groups. They also evaluated whether the women smoked and, if so, how many years they smoked a pack of cigarettes or more each day. They also assessed genetic data from the women to determine whether they carried known genetic risk factors for AMD. They looked most closely at an allele (of the complement factor H (CFH) gene that is known to be associated with higher AMD risk, probing whether the women had zero, 1, or 2 copies of this gene.
People with a pre-existing genetic predisposition for age-related macular degeneration (AMD) significantly increased their odds of developing the blinding eye disorder if they had a history of heavy smoking and consistently did not exercise or eat enough fruits and vegetables, according to a study of women published in the online edition of the journal Ophthalmology.
Eating a healthy diet and getting exercise have been shown in earlier studies to protect against AMD. Findings from this study imply that genetic factors (which we CANNOT change) and lifestyle factors (WHICH WE CAN CHANGE) may contribute to AMD in a synergistic way.
If you have a family history of AMD, the good news is that the study findings suggest that there are still things you can do to potentially lower your risk of developing AMD yourself.
BUT The size of the impact surprised many !
A total of 337 women in the study developed AMD with over 90% developing ‘early-stage disease’ during the study period.
Women in a position of having 2 high risk genes and smoked at least 7 pack-years, and were in the highest-risk diet and exercise categories were more than 4 times more likely to have AMD compared with those women who did not have genetic risk factors and who ate a healthy diet and got at least 10 hours/week of light exercise (such as housework or walking at a pace you could sing to) or at least 8 hours of moderate activity (such as brisk walking).
SO the important thing to note here is that yes we can’t change our age or our genes (though many would dearly love to !) but we can still produce a substantial positive impact on our risk of developing AMD by not smoking, eating well and exercising regularly.
SOURCE: National Institutes of Health