Study links vape use to higher eye disease rates vs quitting

A nationwide analysis in South Korea suggests vape eye disease risk may remain higher for former cigarette smokers who switch to smokeless nicotine rather than quitting nicotine completely.

The research, published in the American Journal of Ophthalmology , drew on Korean National Health Insurance Service records to compare eye outcomes after smoking cessation. Investigators were based at Korea University College of Medicine in Seoul, according to a press release.

Large health-record study tracks quitters vs switchers

Researchers started with 179,273 adults who reported smoking conventional cigarettes in 2011 and 2012. All participants were documented as having quit smoking by 2018 or 2019.

To reduce differences unrelated to nicotine use, the team used a matching approach that paired people with similar characteristics. Matching factors included age, sex, medical history, existing health conditions, and lifestyle patterns.

After matching, the analysis focused on 32,316 participants split into two groups. One group stopped using all nicotine products, while the other shifted to smokeless nicotine products, including electronic vapes.

Higher event rate seen among smokeless nicotine users

Participants were followed for an average of 4.6 years to see who developed major eye diseases. The study tracked outcomes such as cataracts, glaucoma, age-related macular degeneration, diabetic retinopathy, and focus-related vision disorders.

Across the follow-up period, researchers recorded 6,328 major eye disease events in the matched cohort. The lowest overall rate appeared among those who ended all nicotine use.

In that complete-cessation group, the incidence was 41.1 cases per 1,000 person-years, a metric that incorporates both the number of people observed and the length of observation. Among those who moved to smokeless nicotine products, the rate increased to 44 cases per 1,000 person-years.

While the difference between the two rates is modest, it was consistent with the study’s central comparison: nicotine-free cessation was associated with fewer major eye disease events than continued nicotine exposure via smokeless products.

Why the findings add to the nicotine-harm debate

Electronic vapes are frequently discussed as a potential harm-reduction tool for people who would otherwise keep smoking combustible cigarettes. This study, however, framed the question differently by comparing switching against stopping nicotine altogether among people who had already quit cigarettes.

Because all participants had stopped traditional smoking by 2018 or 2019, the results speak to what happens after cigarette cessation, not to whether vaping is safer than continued cigarette use. The findings therefore add to a growing public-health discussion about whether “smokeless” necessarily means lower long-term risk for non-lung outcomes.

The dataset’s scale and the use of national insurance records provide broad coverage, and the matching design aimed to make the two groups comparable on key health and demographic factors. At the same time, the study relies on recorded health and behavior information, and its results should be interpreted in the context of how nicotine-product use is captured in administrative data.

For clinicians and former smokers, the study underscores a practical distinction: quitting cigarettes is one milestone, but eliminating nicotine exposure may confer additional benefits for long-term eye health. For policymakers, the results may influence how cessation programs describe the tradeoffs of switching versus fully discontinuing nicotine.

Next steps to watch include whether other large cohorts in different countries replicate similar incidence gaps, and whether future research can clarify which eye conditions contribute most to the observed difference. Additional follow-up could also show whether risk diverges further over longer periods beyond the average 4.6 years reported in this study.