Diabetic eye disease is the leading cause of blindness among working-age people in the United States and other high-income nations. But recent findings presented on World Diabetes Day suggest that up to one in four people living with the blood sugar disorder aren’t discussing vision issues with their doctors, a situation international health advocates are now trying to change, Medscape reports.

World Diabetes Day is held every year on November 14 to help raise awareness for both type 1 and type 2 diabetes. These metabolic conditions affect the body’s ability to produce insulin, a hormone that lowers blood sugar. This year’s theme focused on how high blood glucose levels can damage blood vessels at the back of the eye and lead to the two most common forms of eye disease affecting people with diabetes: diabetic retinopathy (DR) and diabetic macular edema (DME).

As part of the annual awareness initiative, the International Diabetes Federation (IDF), the International Federation for Aging (IFA) and the International Agency for the Prevention of Blindness (IAPB) surveyed almost 4,340 adults living with diabetes and 2,329 health care providers who specialized in diabetes or vision care across 41 countries.

Findings of the Diabetic Retinopathy Barometer survey showed that one in three respondents living with diabetes said they found the cost of eye exams to be prohibitively expensive. Both ophthalmologists and their diabetic patients said long wait times for an appointment were also a major barrier to quality eye care. In addition, more than half of diabetes eye specialists surveyed said that in many cases, people with diabetes came to them only when vision problems were so severe that it was already too late for treatment.

Results also found that 20 percent of those surveyed with DR or DME—both can lead to total blindness—said changes in their sight made them less able to manage their diabetes. Additionally, 79 percent of people diagnosed with diabetes-related eye problems said their vision loss made activities such as driving, going to work and completing household tasks difficult or impossible.

“DR and DME can be successfully managed with the right screening and treatment,” said Peter Ackland, chief executive officer of the IAPB. “However, many people with diabetes are being placed at unnecessary risk of vision loss due to barriers with the referral system and patient care pathway.”

Click here to learn more about World Diabetes Day and the “Eyes on Diabetes” initiative.