Cigarette smoking is known to play a role in several ophthalmologic diseases, but reports about the effect of smoking on intraocular pressure and glaucoma have had conflicting results. In this study published in the journal Ophthalmology Glaucoma, Drs. Cecilia and Aaron Lee and their co-authors takes advantage of the American Academy of Ophthalmology IRIS (Intelligent Research in Sight) Registry, a database of 60+ million unique patients and 15,000 eye care providers to examine the connection between smoking history and intraocular pressure in more than 12 million smokers, past smokers, and nonsmokers. The authors controlled for other factors known to raise IOP (age, sex, cataract surgery, glaucoma surgery) and compared mean interocular pressure between patients with and without glaucoma according to their smoking history. They found that intraocular pressure was highest in the smoking group, a trend that was present in almost every year of life.
Mean difference in intraocular pressure between current smokers and never smokers. Results are stratified by glaucoma (blue) compared to patients without glaucoma (red) and by decade of life (x-axis). The error bars represent the 95% confidence intervals.
When compared to the other factors, smoking was the most important predictor of IOP after glaucoma. Past and current smokers had higher mean intraocular pressure than nonsmokers regardless of their glaucoma status, but this difference was higher in the glaucoma group and was especially prominent in young smokers (20's-30's). While the effects found were relatively small and within 1 mmHg, the public health implications of this study using Big Data to evaluate the effects of smoking on intraocular pressure at the population level are significant and help to clarify our understanding of smoking as a risk factor for glaucoma. This study did not consider vaping, but these findings raise the question of whether vaping and other forms of nicotine use could also be associated with elevated intraocular pressure. Younger patients with glaucoma who use vaping products may be particularly at risk and warrant future studies.
Lee CS, Owen JO, Yanagihara RT, Lorch A, Pershing S, Hyman L, Miller JW, Haller JA, Chiang MF, Lum F, Lee AY. Smoking Is Associated with Higher Intraocular Pressure Regardless of Glaucoma. Opthalmology Glaucoma, 2020. NIHMSID: NIHMS1580730.