Smoking and Eye Damage
New research into the publicís attitude towards eye health from the
College of Optometrists reveals that a worrying 56 per cent of smokers are unaware that smoking has links to eye disease which could take their sight.
Eye health organizations including the College of Optometrists are concerned about the lack of knowledge about the link between smoking and sight loss. Support amongst the optometry profession is building for an extension of the ĎSmoking Killsí labels introduced on cigarette packaging to include similar warnings linking smoking to eye disease and blindness.
There are many components in cigarette smoke that are toxic -- nicotine, carbon monoxide, tar -- they alter the nutrients that need to reach the eye; they upset the eye chemistry. Nicotine and carbon monoxide in cigarette smoke are thought to be important causes of arteries losing their elasticity. This means that arteries respond less well to fluctuations in pressure and are more likely to rupture.
An even bigger problem is the damage to blood vessels from smoking. The vessels behind the eye can be compromised, which cuts off the flow of oxygen to the eye.
The chemicals in cigarette smoke (around 4000 of them) get into the
bloodstream of smokers and may induce the damage to the
The chemicals in tobacco smoke can cause
inflammation of the conjunctiva (the
thin membrane covering the eye), resulting in bloodshot, irritated eyes.
In a study of nearly 21,000 U.S. male physicians, spanning an average of 13.6
years, researchers found a direct link between smoking and the development of
cataracts. The study, known as Physicians Health Study I, evaluated physicians
between the ages of 40 and 84 who had no prior history of cataracts before 1982.
Participants were asked to complete questionnaires that included information
such as: number of cigarettes smoked daily, age when they started smoking, and
their age if they stopped smoking. Each participant received annual eye exams
and were required to report the results to the study investigators. The
participants' ophthalmologists and optometrists confirmed the results.
Smoking has also been linked to eye diseases such as age-related
degeneration. The causes of macular degeneration are not completely understood,
but smoking is believed to be the main preventable risk factor. Evidence
indicates that more than a quarter of all cases of AMD are linked to current or
past exposure to smoking.
Study results appear mixed about a direct association between smoking and
diabetic retinopathy, but most experts agree that smoking should be avoided to
help help stop progression of the disease.
Smoking causes shrinkage or constriction of blood vessels, shown to be directly
linked to rising inner eye pressure (intraocular pressure) that can lead to
glaucoma and accompanying optic nerve damage.
Optic neuritis : A landmark study found a strong association between factors
such as poor nutrition and smoking linked to a 1992-1993 epidemic of optic nerve
damage among Cuban citizens.
Although smoking is associated with several eye diseases, including nuclear
cataract and thyroid eye disease, the most common cause of smoking related
blindness is age related macular degeneration, which results in severe
irreversible loss of central vision.
How does smoking damage the eyes?
When you inhale cigarette smoke thousands of chemicals get into your bloodstream
and can travel throughout your body. These chemicals cause damage to the macula
(the most sensitive part of the retina, at the back of your eye). Tiny blood
vessels can burst through the macula, leading to irreversible damage, or
alternatively, the cells of the macula slowly die. Both ultimately lead to loss
Can this damage be reversed?
No. Laser treatment can sometimes kill the new blood vessels before they hit the
macula. However, most people are not able to be helped this way because the
blood vessel has already involved the very centre of the macula, and even after
treatment, the condition recurs in half the cases and in almost all those who
continue to smoke. A new treatment, photodynamic therapy (PDT) may be able to
help some to reduce the severity of vision loss, but the majority of people with
macular degeneration will still not be able to be treated.
If I quit smoking will my eyes recover?
Your risk of macular degeneration will be reduced if you quit smoking, however
existing damage to the eyes cannot be repaired, particularly once vision is
Dated 17 October 2011