discovering dry eye
Dry Eye Symptoms
BY CAROLYN G. BEGLEY, OD, MS
In most contact lens practices, the management of dry eye patients is a daily occurrence. The vast majority of dry eye sufferers have mild to moderate cases associated with lens wear. In milder cases, clinical signs don't correlate well with symptoms, so we're forced to use these symptoms as our main diagnostic tools.
Symptoms typically associated with dry eye include: ocular soreness, discomfort, dryness, burning, irritation, grittiness and scratchiness. However, it's not clear how prevalent these symptoms are in the general population or how much they may change over the course of a day. Recently, the dry eye investigation (DREI) developed a questionnaire to study this problem.
Between July 1998 and March 1999, the DREI collected 1015 questionnaires from patients of five optometry schools in the United States and Canada and one private practice. There were two questionnaires -- one for contact lens wearers, and one for nonwearers. The patients' examining doctor also completed a diagnostic form asking whether the patient had dry eye or other anterior segment pathologies. According to the results of their diagnoses, 23 percent of entering non-lens wearing patients had dry eye, with 99 percent in the mild or moderate categories. Fifteen percent of contact lens wearers were diagnosed with dry eye, all of which were in the mild to moderate category.
The most common symptoms among the dry eye patients who did not wear contact lenses were: eye discomfort, dryness, soreness, irritation and itching. Blurry, changeable or foggy vision that clears with a blink was also a relatively frequent symptom. Eye grittiness and scratchiness, light sensitivity and foreign body sensation were less frequent symptoms. Patients reported symptoms to be worse in the evening than in the morning.
Twenty-five percent of the non-lens wearing patients reported that they had worn contact lenses in the past. The questionnaire gave them 13 answers from which to choose to explain why they stopped wearing their lenses. Interestingly, the top four reasons all concerned symptoms of dry eye. They were: eye dryness, discomfort later in the day, scratchiness and irritation, and discomfort all day.
Among patients who filled out the contact lens questionnaire, the most frequent symptom reported was eye dryness. Forty-eight percent of those diagnosed with dry eye reported that their eyes frequently felt dry. However, most of these patients did not report frequent eye dryness without contact lens wear. All contact lens wearers showed a marked trend toward worse dry eye symptoms in the evening, and the shift was even more exaggerated in those diagnosed with dry eye.
The trend toward symptoms worsening in the evening indicates that eye examinations later in the day would be more likely to catch patients symptomatic of dry eye than would morning exams. The diurnal trend in symptoms may be one reason for the poor correlation between symptoms of dry eye and clinical signs.
The worsening of dry eye symptoms over a day is presumably due to accumulated drying of the ocular surface. The majority of patients in the DREI study were diagnosed with mild to moderate stages of the disease, so other underlying pathologies were not likely. In addition, contact lens wearers and non-lens wearers reported similar symptoms of dry eye, which may indicate that the conditions are comparable.
The DREI group would like to thank CIBA Vision for their support of this study.
Dr. Begley is an associate professor at the Indiana University School of Optometry and is also a member of the Graduate Faculty and teaches graduate courses.