If there weren’t already compelling enough reasons for you to quit smoking, think about the risk to your vision.
While it’s well known that smoking can cause cancer, heart disease and stroke, up until recently there has been little awareness about the fact that smoking is also likely to have toxic effects on the retina which can lead to serious and permanent vision loss.
For a long time, I personally bemoaned the fact that Canada had no requirements that cigarette packaging carry a warning about smoking and blindness. Cigarette packaging in other countries – Australia, for example – have carried the message “smoking causes blindness” for some time.
But on June 19, my wish will be granted. New regulations for tobacco products labelling in Canada mean that, as of June 19, retailers can only legally sell cigarettes that display new health warnings, including the fact that smoking increases your risk of blindness.
Specifically, the warning points to the risk of age-related macular degeneration (AMD), which is the leading cause of vision loss in Canadians 50 years and older.
AMD causes damage to the macula, the central part of the retina responsible for seeing fine details (such as reading print or seeing faces). People with AMD generally experience blurred central vision and a growing central blind spot.
We have known for some time that smoking is a major risk factor for AMD.
This new warning is backed by numerous studies from around the globe which have shown that smokers have an increased risk of developing AMD, as well as other eye diseases. Apart from age, smoking has been identified as the most significant risk factor in the development of AMD.
Research also shows that current smokers have up to four times the risk of developing AMD compared to non-smokers or past smokers. Smokers may also develop the disease about 10 years earlier than non-smokers. How much you smoke also affects your risk of acquiring AMD. People who smoke more have a higher risk of developing AMD than those who smoke less, and the disease is more likely to progress from dry AMD (a less severe form of the disease) to wet AMD in people who smoke. Exposure to second-hand smoke also contributes to the risk of developing AMD.
The good news? Quitting can make a difference. Research suggests the damage is reversible. While ex-smokers still have an increased risk of developing AMD compared to people who have never smoked, studies indicate that a person’s risk for AMD decreases each year they don’t smoke. So, after 20 years, the risk for ex-smokers of developing AMD is equal to that of someone who has never smoked.
The findings are consistent among different investigators using different methodologies. And, if that’s not enough, it’s well documented that smoking is also a risk factor for developing cataracts and vision loss from diabetic retinopathy.
While the specific effect of smoking on the eye is not fully understood, it is likely to involve a combination of factors. Most importantly, it has been suggested that smoking is likely to reduce blood flow in the eye, and may also contribute to a reduction in key vitamin and mineral levels in the body that have been shown to help prevent AMD. In any case, the link between smoking and eye disease is clear. One study of AMD in the United Kingdom even suggests that approximately one-quarter of all cases of AMD in that country may be attributable to cigarette smoking in people over the age of 69.
I sincerely hope those people who are still smoking will heed the new warnings about the risk of vision loss. They need to know that living with vision loss can be life altering. Clinical depression is three times as common in people with vision loss compared to the general population. And seniors with vision loss face twice the risk of falls and four times the hip fractures.
If the well-known risks associated with smoking aren’t enough to make you quit, think about the implications of losing your sight.
Dr. Keith Gordon is vice-president, research, at CNIB.
