Age-related macular degeneration — it’s a condition that we should all be conscious of. The risks of this devastating eye problem may not always be controllable, but according to a new study, it turns out that having a genetic predisposition to the condition, along with added exposure to certain risk factors, can make you more vulnerable to contracting it.
The new study, which was published in January’s edition of Archives of Ophthalmology, looks at how the rate of age- related macular degeneration is influenced by a person’s genes in connection to the risk factors that he/she elects to take on, such as smoking and poor diet. It turns out that a mutation of a gene that is related to “complement factor H” (CFH), along with a gene known as “LOC387715” are both linked to age-related macular degeneration. These two mutations are common in white people especially, which means they can also be predisposed to a higher risk of this when adding in external risk factors.
Thanks to both of these mutations occurring, one of the risk factors is an occurrence of age-related macular degeneration. According to the authors of the study, “Elucidation of these modifying factors may increase understanding of disease pathogenesis and suggest lifestyle changes that may prevent AMD or delay the disease onset in carriers of predisposing genetic variants.”
In the study, researchers looked at 457 participants (male and female; average age was 68.7 years) who did have age- related macular degeneration to 1,071 controls who did not have the condition. The participants were enrolled in the famous Nurses’ Health Study, where the researchers gleaned information on age-related macular degeneration from them by examining their case files and having them complete a follow-up questionnaire every two years.
What the researchers found was that individuals who had the two mutations occur — in comparison to healthy individuals who did not have age-related macular degeneration — was that they were 50 times more likely to contract the condition. Also, obesity played a role as well: being obese led to a four times higher risk of developing age-related macular degeneration if a person also had the two mutated genes. Being obese along with having the mutations led to a 12 times higher risk of developing age- related macular degeneration, as opposed to those individuals who were neither obese nor carriers of the gene mutations.
Along with these findings, the researchers discovered that smoking resulted in an 8.69 times higher risk of developing age-related macular degeneration in those individuals with the two gene mutations. On top of this, being a carrier of the LOC387715 gene mutation while being a smoker, translated to a 22.47 greater risk increase for the condition as well, as opposed to nonsmokers who do not have the mutation.
Note that the genetic mutations did not bring on an increase in age-related macular degeneration as other factors have been noted to do, such as fruit consumption, taking aspirin on a routine basis, drinking alcohol regularly, or fatty acid ratios.
Researchers are calling for more screening efforts for age- related macular degeneration in those individuals who may be predisposed to the condition. “The existence of interactions with modifiable lifestyle factors may provide further impetus for screening individuals who are at potentially greater risk [for age-related macular degeneration], for example, cigarette smokers or the obese.”
If people know that they are at risk, explain the researchers, then this may motivate them to give up certain damaging habits, such as smoking, and encourage them to lose weight. Knowing that you may be at risk of age-related macular degeneration should also encourage people to get regular eye exams as well.