Smoking and alcohol intake associated with age-related macular degeneration
A new study by researchers from University College London has shown both smoking and alcohol intake are associated with age-related macular degeneration (AMD). AMD is a leading cause of blindness – its prevalence is expected to increase with population aging, posing a burden to healthcare systems worldwide.
Health efforts need to be directed toward the prevention of advanced AMD. The researchers have thus identified several lifestyle and metabolic risk factors (smoking, alcohol consumption, blood pressure, body mass index, and glycemic traits) critical to prevention.
In a meta-analysis that included data from 16,144 individuals with AMD, it was found that genetically predicted smoking initiation was associated with higher risk of advanced AMD (odds ratio, 1.26), while genetically predicted smoking cessation was associated with lower risk of advanced AMD (odds ratio, 0.66). Similarly, genetically predicted increased lifetime smoking was associated with increased risk of advanced AMD (odds ratio, 1.32).
Besides disruption of retinal epithelium, smoking is associated with the production of inflammatory mediators and activation of the complement cascade involved in the pathogenesis of AMD.
Meanwhile, alcohol as a risk factor for AMD is thought to be related to oxidative damage. From the meta-analysis, there was also an association seen between genetically predicted alcohol consumption and higher risk of geographic atrophy (odds ratio, 2.70).
Evidence was however insufficient to conclude the association between genetically predicted blood pressure, body mass index, and glycemic traits with advanced AMD.
The researchers suggest public health campaigns and programmes incorporate evidence that smoking and alcohol intake can lead to blindness. They further encourage support for smoking abstention, smoking cessation, and reduced alcohol intake to reduce the prevalence of advanced AMD in aging populations.
