Simple questionnaires provide useful baseline for dry eye diagnosis

A dry eye questionnaire can be a useful tool in clinical practice for characterizing the type and severity of dry eye that a patient is experiencing and evaluating the effectiveness of therapeutic intervention, reported Sruthi Srinivasan, PhD.

The clinical diagnosis of dry eye and identifying the causes of the condition so that appropriate treatment can be implemented is an ongoing challenge for clinicians. Adding to the complexities of diagnosis is the fact that the correlation between patients’ self-reported signs and symptoms with objective measures of dry eye is low.

“Patients say they have dry eye, but the tests show that they don’t and vice versa,” said Dr. Srinivasan, who is with The Ohio State University School of Optometry, Columbus, OH.

She and former colleagues at The University of Waterloo, Ontario, Canada, evaluated three commonly used dry eye questionnaires to determine their usefulness for categorizing dry eye in postmenopausal women in the clinical setting.

Dry eye is a common complaint among postmenopausal women. Data from the Women’s Health Study estimated that 3.2 million women aged 50 or more years experience moderate to severe forms of dry eye. Age-related changes in the quality and amount of the tear film also contribute to dry eye in postmenopausal women.

Although women who use hormone replacement therapy (HRT), particularly estrogen alone, to relieve menopausal symptoms are at higher risk for dry eye, few studies have evaluated dry eye symptoms and treatment in postmenopausal women not taking HRT. Dry eye in postmenopausal women is Dr. Srinivasan’s particular research interest.

The study subjects consisted of 82 postmenopausal women aged fewer than 50 years who were not contact lens wearers and not on HRT. At the outset of the study, all subjects took the 12-question Ocular Surface Disease Index (OSDI) questionnaire. Based on these results, 46 women had symptomatic dry eye and 36 were asymptomatic, non-dry eye subjects.

The mean OSDI score for the dry eye group ranged from 18.37 ± 9.29 for women with mild dry eye to 28.31 ± 13.02 for women with moderate dry eye (p <0.001). In the asymptomatic, non-dry eye group, the mean OSDI score was 7.43 ± 7.71.

All subjects then took the Indiana Dry Eye Questionnaire (DEQ), a 23-question assessment. Indiana DEQ scores showed that women with dry eye experienced a higher frequency and intensity of symptoms than did women without dry eye (p <0.001), and that these symptoms worsened as the day progressed. Symptoms that were reported as “frequent” included discomfort and dryness (54% and 41%, respectively). A significant difference was found between the dry eye and non-dry eye groups in their scores for the majority of symptoms, including comfort, dryness, soreness and irritation, grittiness and scratchiness, and burning and stinging (p <0.001).

The single-item score dry eye questionnaire (SIDEQ) was administered to all subjects. This questionnaire consists of one question that asks patients to rate the frequency that they experience ocular dryness on a scale from 0 to 4. Responses revealed 43 subjects with dry eye (16 mild and 27 moderate) and 39 asymptomatic, non-dry eye subjects.

Correlation between questionnaires is high

Researchers found a moderate to high correlation across all three dry eye questionnaires, indicating that any of the questionnaires is useful for placing individuals in a dry eye group or a non-dry eye group, Dr. Srinivasan said, adding, “Although there are some questions in common, each questionnaire has its own uniqueness.”

The OSDI is a validated, standardized tool for symptom evaluation that can be performed easily, she said. It also is one of the most commonly used dry eye assessments in clinical practice.

“One advantage is that the OSDI provides an easy computation to arrive at a conclusion. OSDI is easy to use and can be a valuable tool for diagnosing dry eye based on symptoms,” Dr. Srinivasan said.

Study co-author Lyndon Jones, PhD, a professor in the School of Optometry at Waterloo University, said that the Indiana DEQ is the only dry eye questionnaire currently available that evaluates changes in ocular surface symptoms of dryness and diurnal fluctuation in symptoms.

“These variations can be of particular importance in treatment planning,” he said. The Indiana DEQ also includes questions about the degree to which dry eye symptoms interfere with the individual’s daily activities.

The simplest of the questionnaires, the SIDEQ, also has application in the clinical setting, Dr. Jones said.

“The study demonstrated that the more complex questionnaires correlated with SIDEQ, suggesting that for a quick evaluation in the office, SIDEQ is a good starting point,” he said.

The study results underscore the need for developing more sensitive and specific tests for diagnosing dry eye, possibly disease biomarkers. Until such tests are available for clinical use, Dr. Srinivasan said, “Symptoms are an important aspect of dry eye disease, and the various questionnaires are an easy way to evaluate symptoms, categorize patients by severity, and determine their response to treatment.”