Justin Timothy Kwan

Associations with Meibomian Gland Atrophy in Daily Contact Lens Wearers.

Purpose To determine associations for contact lenses (CLs) and meibomian gland atrophy in a matched-pair study. Methods Contact lens wearers (case) and age- and sex-matched non–contact lens (NCL) wearers with no history of CL use (control) were recruited for a multicenter study. All subjects were administered the Ocular Surface Disease Index questionnaire and a comprehensive battery of clinical tests (e.g., tear breakup time, bulbar and limbal redness, meibography, etc.) were performed. Upper and lower eyelid meibomian gland atrophy were graded with both digital meibography (percent gland atrophy) and visual meiboscore methods. Conditional logistic regression analyses were then used to determine relationships among CL use, meibomian gland atrophy, and ocular surface signs and symptoms. Results A total of 70 matched pairs were analyzed. The mean (±SD) age of the CL group was 30.6 (±12.4) years, and that of the NCL group was 30.1 (±12.2) years. The subjects were 63% female. The association between CL wear and meiboscore was not significant univariately, but the best-fitting multivariate regression model showed that higher meiboscores were associated with being a CL wearer (odds ratio [OR], 2.45) in a model that included eyelid margin erythema (OR, 0.25) and lissamine green staining (OR, 1.25). Percent gland atrophy was not associated with CL wear in regression analysis (p = 0.31). Conclusions This study determined inconclusive associations with CLs and meibomian gland atrophy. This study also provided a comprehensive assessment of differences between CL and NCL wearers.

Psychometric Analysis of the SPEED Questionnaire and CLDEQ-8

Purpose This study reports on the ability of the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire to detect dry eye (DE) symptoms in contact lens (CL) and non-CL wearers. Methods The SPEED questionnaire was administered to all subjects while the Contact Lens Dry Eye Questionnaire-8 (CLDEQ-8) was only administered to CL wearers. Tear meniscus heights (TMH) were measured, and the phenol red thread (PRT) test was conducted. These tests along with self-reported DE were used to identify subjects with dry eye disease (DED). Rasch analysis was performed to evaluate the questionnaires for measurement precision and unidimensionality, and the scores from these Rasch analyses were used to understand their ability to predict measures of DED. Results We enrolled 284 subjects (150 CL and 134 non-CL wearers). Mean subject age was 39.4 ± 14.2 years. Rasch analysis yielded a multidimensional short form of the SPEED questionnaire (8-items) and a unidimensional short form of the CLDEQ-8 (4-item). Scores from both questionnaires were significantly associated with self-reported DE in CL and non-CL wearers. Scores of the 8-item SPEED questionnaire were associated with DED status in non-CL wearers but not in CL wearers while 4-item CLDEQ scores were associated with DED status in CL wearers. TMH or PRT were not associated with either questionnaire in CL or non-CL wearers. Conclusions The 8-item SPEED questionnaire demonstrated adequate measurement precision with evidence of quantifying multiple symptoms categories while the 4-item CLDEQ-8 primarily quantified DE symptoms. Questionnaire scores were associated with self-reported DE, which suggests that they may have utility in both populations analyzed.

Development of a Meibomian Gland Dysfunction-specific Symptom Questionnaire.

Objectives: The aim of this study was to develop and evaluate, using psychometric approaches, a meibomian gland dysfunction (MGD)-specific questionnaire in noncontact lens wearers. Methods: The MGD subjects were recruited and classified as the MGD dry eye subtype based on accepted tests (e.g., Schein symptom survey, tear breakup time, corneal and conjunctival staining, abnormal meibum or meibomian gland atrophy, and a normal Schirmer test). The MGD questionnaire items were drawn from published and anecdotal sources. The preliminary instrument contained 24 items targeting the frequency and intensity of 12 symptoms. Rasch analysis was used for psychometric evaluation of the survey items. Results: Sixty nine MGD subjects completed the survey and clinical testing. Sample severity levels were as follows: none subclinical, 10 minimal, 43 mild, 16 moderate, and none severe. Three iterations of analysis, eliminating INFIT and OUTFIT scores <, and >3.0, and using subject responses reduced the final questionnaire to seven question pairs. Final analysis for the remaining 14 items demonstrated an excellent fit to the Rasch model (e.g., for persons, INFIT MNSQ=0.97; ZSTD=−0.2; OUTFIT MNSQ=0.96; ZSTD=−0.2; item fit statistics were similar). Construct validity also seems good (e.g., correlation to Schein and change with treatment). Conclusions: The MGD-specific instrument is a valid quantitative measure of the symptoms stemming from MGD sufferers. Further research is necessary to determine whether diagnostic efficacy is sufficient to differentiate the MGD dry eye subtype in an independent sample of normals and both major dry eye subtypes exhibiting a broad severity range.