Smoking, vaping linked to eye problems in young people
A new study has found a link between cigarette and e-cigarette use by adolescents and young adults and the frequency and severity of eye problems they reported. The researchers say healthcare clinicians should use their findings to educate smokers and vapers about the risks to eye health.
While the health risks associated with smoking cigarettes are very well-documented, those associated with using electronic or e-cigarettes, otherwise known as vaping, are only now being investigated, especially in young people.
Since 2014, e-cigarettes have been the most common tobacco product used among youth in the US. Already, the practice of vaping has been linked to increased blood pressure, heart rate, air resistance in the lungs, and immune system reactions. Some people choose to use either cigarettes or e-cigarettes, and some use both.
Researchers at McGill University, Canada, decided to focus on the frequency and severity of symptoms of eye problems reported by adolescent and young adult users of cigarettes and e-cigarettes, a little-researched area.
They recruited 4,351 Americans aged between 13 and 24 years. The participants were categorized according to their use of cigarettes, e-cigarettes, or both. They were asked whether they had ever used an e-cigarette or cigarette, even just a puff (‘ever users’). Ever users were then asked whether they’d used in the past 30 days (‘past 30-day users’). Past 30-day users were then asked whether they had used it in the past seven days (‘past seven-day users’). Participants answered similar questions regarding their use of other combustibles, including blunts, cigars/cigarillos, and smoked cannabis.
Participants were asked to rate their eyesight. They were also asked to indicate the frequency and severity of 10 symptoms occurring in and around their eyes: ocular discomfort, pain/aching, burning/stinging, itching, redness, dryness/gritty sensation, glare/sensitivity to light, blurry vision, tired/eye strain, and headaches.
Among the 4,351 participants, 50.2% used e-cigarettes and 36.5% smoked cigarettes at least once in their life (ever users). Among the 2,183 e-cigarette ever users, 55.9% also used cigarettes (‘dual users’). Among the 1,092 past 30-day users, 44.3% were dual users. Among the 919 past seven-day users, 45.8% were dual users. Among all participants, 54.8% used other combustible substances at least once in their lifetime.
After adjusting for sociodemographic factors, contact lens use, and use of other combustible substances, participants who used only cigarettes at least once in their life had a higher likelihood of experiencing more severe burning/stinging in their eyes and blurry vision compared with all other participants. The same participants had a higher likelihood of experiencing more frequent burning/stinging and dryness/gritty sensation compared to all other participants.
Past 30-day users of only cigarettes had a higher likelihood of having more severe and more frequent blurry vision compared with all other participants. Past seven-day users of only cigarettes had a higher likelihood of having more severe blurry vision compared with all other participants, and more likely to have more frequent pain/aching and blurry vision.
Between 1.1% and 3.9% of dual ever users reported severe to very severe ocular symptoms and between 0.9% and 4.3% reported daily symptoms. Participants who used both e-cigarettes and cigarettes at least once in their life (dual ever users) had a higher likelihood of experiencing more severe dryness/gritty sensation and blurry vision compared with all other participants.
Past 30-day dual users were most likely to have more severe and more frequent eye discomfort, pain/aching, burning/stinging, itching, redness, dryness/gritty sensation, glare/light sensitivity, blurry vision, and headaches compared with all other participants. Past seven-day dual users were most likely to have more severe and more frequent eye discomfort, pain/aching, burning/stinging, itching, redness, dryness/gritty sensation, glare/light sensitivity, blurry vision, headaches, and tired/strain compared with all other participants.
The researchers say their findings suggest that dual users are at increased risk of ocular symptoms, regardless of the frequency of cigarette and e-cigarette use. They hypothesize that the cause of eye issues in both cigarette and e-cigarette users is due to oxidative stress, which can be implicated in constriction of the blood vessels (vasoconstriction) in the eye.
They recognize that the study has some limitations. Mainly, the number of cigarettes smoked can’t be directly applied to e-cigarette dosage, so they were unable to compare both products in terms of mild, moderate, and heavy use. And the study does not establish a causal link between cigarette and e-cigarette use and ocular symptoms. Nonetheless, they consider the study’s findings to be useful.
“Further longitudinal studies are necessary to validate our findings,” said the researchers. “These findings provide additional reasons to screen, counsel, and treat all tobacco users to prevent and reduce ocular symptoms. We recommend that health care clinicians ask all patients about nicotinic product use and counsel and treat those using these products to help prevent and reduce ophthalmologic issues.”
The study was published in the journal JAMA Ophthalmology.