Dry eye has been associated with the following factors:
Older age - i.e., after age 50
Contact lens wear
Working or living in a dry, smoky or windy environment
Smoking
Certain health conditions - e.g., diabetes, lupus, rheumatoid arthritis, Sjogren's syndrome
Prolonged computer use that slows down normal blink rate
Certain medications - e.g., antihistamines, antidepressants, birth control pills