Dry eye -- the culprit behind red, watery, gritty-feeling eyes -- strikes most often in spring due to a surge in airborne allergens, a study says.
Dry eye cases reach a yearly peak in April, the study pointed out.
"For the first time, we have found what appears to be a connection between spring allergens like pollen and dry eye, but also saw that cases rose in winter," said lead researcher Anat Galor, associate professor of clinical ophthalmology at the Bascom Palmer Eye Institute at the University of Miami.
Dry eye can significantly impact a person's quality of life by inducing burning, irritation and blurred vision.
The latest discovery that allergies and dry eye conditions are linked suggests dry eye sufferers may benefit from allergy prevention in addition to dry eye treatments like artificial tears.
For instance, wearing goggles outside for yard work and using air filters indoors may stave off springtime dry eye, the researchers said.
The researchers discovered the correlation between allergies and dry eye by reviewing 3.4 million visits to eye clinics nationwide over a five-year period between 2006 and 2011.
During that time, doctors diagnosed nearly 607,000 patients with dry eye. Researchers also charted the monthly prevalence of dry eye compared to an allergy index over time and found seasonal correlations,
A seasonal spike occurred each spring, when 18.5 percent of patients were diagnosed with dry eye. Another spike came in winter. Prevalence of dry eye was lowest in summer at 15.3 percent.
April had the highest monthly prevalence of dry eye cases: 20.9 percent of patients seen were diagnosed with dry eye that month.
The research team hypothesises that the winter rise in cases of dry eye may be due to low indoor humidity caused by people using heaters indoors without a humidifier to offset the dryness.
The study was published online in the journal Ophthalmology.
