First author Dustin French, a research scientist at the Veterans Health Administration, Health Services Research and Development Service in Indianapolis and Regenstrief Institute, said a study involved the 5.3 million men and women seen in Department of Veterans Affairs outpatient clinics in a one-year period.
The study, published in the Journal of Glaucoma, found the use of cocaine is predictive of open-angle glaucoma -- the most common type of glaucoma and the second-most common cause of blindness in the United States.
However, men with open-angle glaucoma also had significant exposures to amphetamines and marijuana, though not as much as to cocaine.
In addition, patients with open-angle glaucoma and history of exposure to illegal drugs were nearly 20 years younger than glaucoma patients without a drug exposure history -- age 54 vs. age 73.
"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," French said in a statement.
French and colleagues found that among the 5.3 million veterans who used VA outpatient clinics in fiscal year 2009 -- 91 percent of whom were male -- nearly 83,000, or about 1.5 percent, had glaucoma.
During the same fiscal year, nearly 178,000, or 3.3 percent, of all those seen in the outpatient clinics had a diagnosis of cocaine abuse or dependency, French said.
Notable deaths of 2014 [PHOTOS]