Cocaine can be a serious threat to sight, according to a study showing that current and former cocaine users have a 45% increased risk of glaucoma. The drug can cause open-angle glaucoma—the most common type of glaucoma and the second most common cause of blindness in the US—found the survey of 5.3 million men and women in Department of Veterans Affairs outpatient clinics over a one-year period, which is published in the Journal of Glaucoma. Men with open-angle glaucoma were also associated with a high exposure to pot and amphetamines—though less so than cocaine. These patients also picked up the condition significantly younger than drug-free glaucoma patients—a disturbing 20 years younger than average. Of the 5.3 million vets who used VA outpatient clinics in 2009, about 83,000—1.5%—had glaucoma, of whom nearly 91% were male. About 178,000—3.3%—of all those seen in the outpatient clinics had a diagnosis of cocaine abuse or dependency. The study’s first author, Dustin French, a research scientist at the Veterans Health Administration, Health Services Research and Development Service in Indianapolis concluded: “The association of illegal drug use with open-angle glaucoma requires further study, but if the relationship is confirmed, this understanding could lead to new strategies to prevent vision loss.”