People with chronic dry eye may find the condition slows them down when they have to read beyond a couple of paragraphs, a new study suggests.
Researchers found that compared with people without dry eye, those with the condition read at a slower rate when they were tasked with a 7,200-word passage.
The study authors said that traditional reading tests given during eye exams — at around 75 words — may miss the difficulties that dry eye can cause with prolonged reading.
Chronic dry eye is common, particularly after the age of 50. Nearly 5 million Americans in that age group have the condition, according to the American Academy of Ophthalmology (AAO).
The symptoms of dry eye include burning, redness, stinging or a gritty feeling in the eyes; sensitivity to irritants like wind or cigarette smoke; and excessive tearing, as the eyes sometimes overproduce tears in response to the dryness, the AAO notes.
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It’s common for people with dry eyes to complain of problems with reading, researcher Dr. Sezen Karakus says.
But those complaints do not always fit with what’s seen during eye exams — which may suggest the person’s vision is fine, Karakus, an assistant professor of ophthalmology at Johns Hopkins University explains.
So the investigators decided to dig deeper, using a longer reading test developed by one of Karakus’ colleagues, Dr. Pradeep Ramulu. It takes about 30 minutes to complete and basically simulates reading a book, Karakus shares.
The researchers recruited a group of adults older than 50. The group included 116 people with “clinically significant” dry eye. That meant they showed certain abnormalities on the cornea — the transparent surface of the eye — and differences in tear production.
Another 39 study participants complained of some dry eye symptoms, but had no abnormal eye exam findings. Finally, 31 people without dry eye signs or symptoms served as a control group.
On average, the study found, the three groups had similar reading rates on a standard, out-loud reading test. But differences cropped up when they took the silent, prolonged reading test. People with clinical dry eye read at