Several research teams recently tackled the complicated relationships between lifestyle choices and the risk of developing glaucoma, and presented their findings last week at ARVO 2019. Not surprisingly, drinking coffee and smoking can increase the risk and a healthy lifestyle and diet can decrease the odds.

Coffee and Glaucoma

Adding to the evidence that drinking coffee can increase one’s glaucoma risk, researchers from Korea found that coffee consumption—compared with tea or soda—enhanced the odds of developing open-angle glaucoma in men.¹

Researchers used data from the Korea National Health and Nutrition Examination from 2010-2011. This population-based, cross-sectional survey included 7,608 participants. Investigators reviewed data on demographics, comorbidities and health-related behaviors and performed comprehensive ophthalmic exams.

Researchers reported no significant difference in the intraocular pressure among those who consumed coffee, tea and soda. However, the study found coffee consumption showed a statistically significant relationship with the presence of open-angle glaucoma, while no significant relationship was found between those who drank tea or soda.

The adjusted odds ratio for open-angle glaucoma amongst those who drank coffee and those who didn’t was 2.11. Additionally, coffee consumption appeared to have a greater link to open-angle glaucoma in males than in females.

Limiting coffee could be helpful for decreasing glaucoma risk, researchers noted, although they add that further studies are needed to evaluate the exact underlying mechanisms. 

Healthy Lifestyle

The Seguimiento Universidad de Navarra (SUN) Project is a prospective cohort study conducted in Pamplona, Spain focused on nutrition, lifestyle and chronic diseases.² The study included 28,247 participants who were initially glaucoma-free. The subjects were prospectively followed for approximately 11 years and were evaluated based on a healthy lifestyle score consisting of nine habits (ranging from zero to 10 points): never having smoked; moderate-to-high physical activity; eating a Mediterranean diet; moderate alcohol consumption; low television exposure; no binge drinking; taking a short afternoon nap; meeting friends; working at least 40 hours a week and low body mass index.

During follow-up, researchers observed 260 (1.42%) new cases of glaucoma. After adjusting for potential confounders, participants in the highest category of healthy lifestyle score adherence (seven to 10 points) showed a significantly reduced risk of developing glaucoma compared with those in the lowest category (zero to three points). Investigators also found never smoking was associated with a low glaucoma incidence.

Genetics Reveals Smoking Association

In a third study, UK researchers found a link between smoking and glaucoma by comparing the genes of affected individuals and those without the condition.³

Researchers used published data from 361,194 patients in the UK Biobank and considered single nucleotide variants that were associated with smoking behavior at genome-wide significance and tested their association with AMD, glaucoma and cataracts.

“Our evidence suggests that smoking increases the risk of glaucoma and cataracts. There was no association between smoking and AMD,” the researchers wrote in their ARVO abstract.

This is the first Mendelian randomized study to investigate an association between smoking and eye disease, the study noted.

“The positive association with glaucoma adds weight towards a causal effect, which may be vascular in origin,” the investigators wrote in their abstract.

They attributed the lack of association between smoking and AMD to the fact that the UK Biobank AMD data was self-reported and derived from a relatively young cohort, which likely reduced case numbers and incidence rates. Investigators said they hope to test the association in different populations and evaluate other potential risk factors.