When smokers used both cigarettes and e-cigarettes, studies showed additional detrimental findings, such as lower general health, increased sleep latency, and higher vascular disorder risk.
Anne X Nguyen, MD, and colleagues reported the occurrence of severe and frequent ocular symptoms more likely among young individuals who ever used both cigarettes and e-cigarettes.1 She is from the Faculty of Medicine, McGill University, Montréal, Quebec, Canada.
According to the study authors, numerous adverse effects have been associated with the use of e-cigarettes since they were introduced into the marketplace. Among those are increased blood pressure, heart rate, air resistance in lungs, and immunomodulatory cytokines production.2,3
When smokers used both cigarettes and e-cigarettes, studies showed additional detrimental findings, such as lower general health, increased sleep latency, and higher vascular disorder risk.4-7
The investigators pointed out that few studies have reported the effects of these smoking products on eyes. They theorized the following: that use of both types of smoking products might result in more frequent and severe ocular symptoms than those who used just 1 of the products, those who used 1 or both products in the past 7 days would have more ocular symptoms than those who used these products in the past 30 days, and those who used 1 or both products in the past 30 days would have more ocular symptoms than those who used these products at least once during their lives.
Nguyen and colleagues conducted an observational cross-sectional study and administered a survey from May 6 to 14, 2020, to determine the frequency and severity of ocular symptoms. The symptoms included ocular discomfort, pain, burning, itching, redness, dryness, glare, blurriness, strain, and headaches in adolescents and young adults who used e-cigarette and cigarettes.
The survey questioned participants aged 13 to 24 years about the use of smoking products, ie, having ever used them and used them in the previous 7 days and the previous 30 days.
The main outcomes were correlations between vision-related outcomes, that is, general vision and severity/frequency of ocular symptoms, and tobacco use.
A total of 4,351 individuals (63.8% female; mean age, 19.1 years) were included. The authors reported that regarding e-cigarettes, 2,168 were never users, 2,183 ever users, 1, 092 past 30-day users, and 919 past 7-day users and that 55.9% of e-cigarette ever users also used cigarettes (dual users).
Among individuals described as dual ever users 1.1% and 3.9%, respectively, reported severe to very severe ocular symptoms; between 0.9% and 4.3% reported daily symptoms, which was higher than the proportion of symptoms among those who used only e-cigarettes or only cigarettes.
Those who reported dual use of the smoking products during the previous 7 days described more severe itching (adjusted odds ratio [AOR], 2.37; 95% confidence interval [CI], 1.36-4.13; P = 0.002), redness (AOR, 2.58; 95% CI, 1.50-4.46; P = 0.001), dryness (AOR, 2.89; 95% CI, 1.64-5.08; P < 0 .001), glare (AOR, 2.56; 95% CI, 1.50-4.35; P = 0.001), blurriness (AOR, 2.47; 95% CI, 1.36-4.50; P = 0.003), headaches (AOR, 2.31; 95% CI, 1.34-4.00; P = 0 .003); and more frequent pain (AOR, 3.45; 95% CI, 2.09-5.68; P < 0.001), burning (AOR, 3.08; 95% CI, 1.86-5.09; P < 0 .001), and redness (AOR, 2.72; 95% CI, 1.69-4.36; P < 0.001) compared with all other participants.
Those who reported dual use during the previous 30 days described more severe dryness (AOR, 2.65; 95% CI, 1.61-4.36; P < 0 .001) and more frequent pain (AOR, 3.33; 95% CI, 2.12-5.21; P < 0.001) than all other participants.
Those who reported ever engaging in dual use described more severe dryness (AOR, 1.60; 95% CI, 1.05-2.43; P = 0 .03) and blurriness (AOR, 1.79; 95% CI, 1.21-2.64; P = 0.003) and more frequent pain (AOR, 1.69; 95% CI, 1.13-2.53; P = 0 .01) and blurriness (AOR, 1.63; 95% CI, 1.13-2.36; P = 0 .009) than those who had never used the smoking products.
Nguyen and colleagues commented, “In this cross-sectional US study, adolescents and young adult users of both e-cigarettes and cigarettes had a higher likelihood of experiencing severe and frequent ocular symptoms, with past 7-day users reporting more symptoms than past 30-day users or ever users. These findings provide additional reasons for users of e-cigarettes and cigarettes to reduce their tobacco use to possibly prevent or minimize ocular symptoms.”