Greater Alcohol Intake Raises IOP, But Not Glaucoma Risk

Greater alcohol intake is associated with higher intraocular pressures (IOP), but not elevated incidence of glaucoma, according to a population-based analysis published in Investigative Ophthalmology & Visual Science. The study evaluated the effect of alcohol intake on intraocular pressure (IOP) and glaucoma, and assess whether any associations are modified by a glaucoma polygenic risk score (PRS).

The cross-sectional study assesses information for 30,097 individuals, 45 to 85 years of age, who participated in the Canadian Longitudinal Study on Aging (CLSA) Comprehensive Cohort. Data were gathered from clinical visits, blood samples, and personal interviews in 11 widely spread communities during the first round of CLSA from 2012 to 2015. Physician diagnosis of glaucoma and frequency of alcohol intake were self-reported.

Using a linear regression model that adjusted for health, lifestyle, and other demographic factors, researchers found an association between daily alcohol use — 6 or more times each week and higher IOP vs never drinkers (β=0.45, 95% CI, 0.05-0.86). However, no significant link to IOP emerged for frequency of 1 to 5 drinks per week, or occasional use, 0 to 3 times monthly (P >.05). Considering quantity, IOP was higher with a weekly 5-drink increase (β=0.20, 95% CI, 0.15-0.26).

In logistic regression analysis, also adjusted for demographic and other variables, drinking frequency did not show a substantial association with glaucoma incidence (P >.05). Similarly, no statistically important relationships arose between glaucoma and total intake, or type of alcohol — wine, beer, or liquor (P >.05).

Further, consumption quantity strongly correlated with IOP in individuals with higher PRS scores (P_interaction =.041).

“Consuming an increased frequency and amount of alcohol, particularly red wine and beer, was associated with higher levels of IOP, whereas it was not associated with the prevalence of glaucoma,” the researchers report. “Daily drinkers had an IOP that was 0.45 mm Hg higher than people who never drank alcohol.”

Limitations of this study included no available data for glaucoma subtype or severity, caffeine or sodium, or RNFL and macular thickness. Alcohol use may have been underreported. PRS did not greatly impact relationships among drinking frequency or quantity and glaucoma incidence, affirming prior results found in the UK Biobank.