Smokers are almost four times as likely to become blind in later life than non-smokers, according to a paper published in the British Medical Journal today.
The authors of the leading article, who are eye specialists and public health doctors, said there was "strong evidence of a causal link between tobacco smoking and age related macular degeneration (AMD)".
This is a condition, predominantly found in those over the age of 50, in which central vision deteriorates and may be completely lost. The macula is part of the retina, an area at the back of the eye where visual images come together before being transmitted to the brain.
Based on an analysis of three studies, involving 12,500 patients, which showed that smokers had a four-fold increased risk compared with people who had never smoked, the authors stated that the commonest cause of smoking-related blindness is AMD. They also found that quitting smoking slows the development of AMD, while continuing to smoke with the condition can affect the long-term response to treatments such as laser therapy.
It is estimated that over 60,000 people in the Republic have AMD. According to Mr Stephen Beatty, consultant ophthalmic surgeon at Waterford Regional Hospital, "AMD is the leading cause of vision loss for people over the age of 50 in the western world, affecting 25-30 million people.
Early detection is vital to prevent or at least slow down the potentially devastating effect on a person's independence".
The authors of today's report call for sustained public health campaigns to increase awareness of the eye hazards associated with smoking.
The exact mechanism by which smoking causes AMD is not clear but is thought to relate to damage to the retina caused by cigarette smoke blocking the protective effect of antioxidants.