Natural history of dry eye disease: Perspectives from inter-ethnic comparison studies

Epidemiology and Risk Factors of Dry Eye Disease: Considerations for Clinical Management

Dry eye disease is a multifactorial condition characterised by tear film instability, hyperosmolarity and ocular surface inflammation. Understanding the epidemiology of dry eye disease and recognising both modifiable and non-modifiable risk factors can assist eye care practitioners in assessing, treating, and managing patients with the condition. This review considers current knowledge surrounding its incidence and prevalence, as well as associated demographic, systemic, ocular, and iatrogenic, and lifestyle-related modifiable risk factors. Population-based prevalence estimates vary according to the diagnostic criteria used to define dry eye disease, as well as severity and demographic characteristics of the population. Considering recent data and variable population demographics, conservative prevalence estimates suggest that 10-20% of the population over 40 years of age report moderate to severe symptoms and/or seek treatment for dry eye disease. Individuals with specific non-modifiable demographic risk factors may be at increased risk of developing dry eye disease. Advanced age, female sex and East Asian ethnicity have been identified as key non-modifiable demographic features predisposing individuals to dry eye disease. Systemic conditions that have been associated with an increased risk of dry eye disease include migraine, Sjögren syndrome, connective tissue disorders, mental health disorders, diabetes mellitus and androgen deficiency. Medications that may contribute to this risk include antidepressants, antihistamines, and hormone replacement therapy. Ocular and iatrogenic risk factors of dry eye disease include blepharitis, Demodex infestation, ocular surgery, blink completeness, contact lens wear, and topical ophthalmic medications. A range of modifiable lifestyle factors that can increase the risk of dry eye disease have also been identified, including low humidity environments, digital screen use, quality of sleep, diet, and eye cosmetic wear. Dry eye is a common disease affecting millions globally. Increasing knowledge regarding its associated risk factors can better prepare the eye care practitioner to successfully manage patients with this ocular surface disease.

Discriminative performance of ocular surface staining and lid wiper epitheliopathy in dry eye disease: An investigator-masked, prospective registry-based, diagnostic accuracy study

PURPOSE

To evaluate the diagnostic performance of corneal and conjunctival staining, and lid wiper epitheliopathy (LWE) in detecting dry eye disease, as defined by the global consensus Tear Film and Ocular Surface Society Dry Eye Workshop II (TFOS DEWS II) criteria.

METHODS

A total of 2066 community residents (1285 females; mean ± SD age, 40 ± 19 years) were recruited in an investigator-masked, prospective registry-based, diagnostic accuracy study. Dry eye symptomology and ocular surface parameters were assessed in a single clinical session. The Sjögren's International Collaborative Clinical Alliance (SICCA) corneal and conjunctival staining scoring and Korb lid wiper epitheliopathy (LWE) grading were evaluated by an independent masked assessor.

RESULTS

Overall, 807 (39 %) participants fulfilled the TFOS DEWS II criteria for dry eye disease, of which 178 (9 %) participants were classified as moderate-to-severe disease. The discriminative abilities of superior and inferior LWE (C-statistics, 0.724 and 0.712, respectively) were greater than corneal and conjunctival staining (C-statistics, 0.573 and 0.627, respectively). The Youden-optimal diagnostic cut-offs for the SICCA corneal and conjunctival staining scores were both ≥1, and the optimal thresholds for the Korb superior and inferior LWE grades were both ≥1. LWE was more commonly detected in both mild-to-moderate and moderate-to-severe dry eye disease, and demonstrated more consistent correlation with other ocular surface parameters across a broader range of disease severity.

CONCLUSIONS

LWE demonstrates superior diagnostic performance relative to corneal and conjunctival staining. These findings would support the routine incorporation of LWE evaluation as part of the diagnostic workup of dry eye disease.

Predictive performance of corneal and lid margin sensitivity for dry eye disease: An investigator-masked, prospective, prognostic accuracy study

PURPOSE

To evaluate the prognostic ability of non-contact esthesiometry corneal and lid margin sensitivity measurements in detecting symptoms and signs of dry eye disease, as defined by the global consensus TFOS DEWS II criteria.

METHODS

A total of 87 community residents (58 females; mean ± SD age, 53 ± 16 years) were recruited in an investigator-masked, prospective, prognostic accuracy study. Dry eye symptomology, tear film parameters, and ocular surface characteristics were evaluated in a single clinical session, and non-contact esthesiometry corneal and lid margin sensitivity measurements performed by an independent masked assessor.

RESULTS

Overall, 49 (56%) participants fulfilled the TFOS DEWS II criteria for dry eye disease, while 57 (66%) exhibited clinical symptoms, and 67 (77%) had positive signs. The prognostic abilities of corneal and lid margin sensitivity measurements were significantly greater than chance for the detection dry eye signs (both p ≤ 0.03), but not for symptoms or overall disease diagnosis (all p > 0.10). The Youden-optimal prognostic cut-offs for corneal and lid margin sensitivity thresholds were both ≥0.8 mbar for the detection of clinical dry eye signs. Lid margin sensitivity demonstrated marginally higher predictive performance than corneal sensitivity (C-statistic, 0.688 versus 0.658), and was significantly correlated with tear film stability, corneal, conjunctival and lid wiper staining (all p < 0.05).

CONCLUSIONS

Corneal and lid margin sensitivity demonstrated moderate prognostic utility for detecting clinical dry eye signs. Future research is warranted to investigate the utility of incorporating non-contact esthesiometry in the workup for dry eye disease and neurotrophic keratopathy.

Digital eye strain and its impact on working adults in the UK and Ireland

CLINICAL RELEVANCE

Digital eye strain (DES) is a condition encompassing visual and ocular symptoms that may arise due to the prolonged use of digital devices. The 2023 Tear Film Ocular Surface Lifestyle report defined DESas"the development or exacerbation of recurrent ocular symptoms and / or signs related specifically to digital device screen viewing". Studies vary as to the prevalence of DES with some reporting values as low as 10 % and some reporting values over 90 %, however no study has examined the prevalence of DES in the UK or Ireland (UK&I).

PURPOSE

To determine the prevalence of DES amongst adults who work with digital devices in UK&I, their symptoms and ameliorative approaches taken by those affected.

METHODS

A web-based survey of digital device users was conducted. Adults who used a device for at least 1 h per day for work purposes were eligible to participate. The questionnaire was designed to determine the prevalence of DES, daily device usage, musculoskeletal and ocular symptoms, how they manage their symptoms and eye care history.

RESULTS

Based on a Computer Vision Syndrome Questionnaire score ≥ 6, the occurrence of DES was high at 62.6 %. The mean number of hours devices were used for was 9.7 h. Musculoskeletal symptoms were reported by 94.3 % of users and ocular symptoms by 89.5 % with symptoms most likely to occur with those working from home. 8.1 % of respondents considered their symptoms significant enough to affect their work.

CONCLUSION

This study provides a valuable insight into DES in digital device users in UK&I and is the first of its kind to be completed. It shows, that while the level of DES is high in device users, at 62.6 %, the actual effect or consequences of it on many does not appear to be significant.

Predicting Risks of Dry Eye Disease Development Using a Genome-Wide Polygenic Risk Score Model

Purpose

The purpose of this study was to conduct a large-scale genome-wide association study (GWAS) and construct a polygenic risk score (PRS) for risk stratification in patients with dry eye disease (DED) using the Taiwan Biobank (TWB) databases.

Methods

This retrospective case-control study involved 40,112 subjects of Han Chinese ancestry, sourced from the publicly available TWB. Cases were patients with DED (n = 14,185), and controls were individuals without DED (n = 25,927). The patients with DED were further divided into 8072 young (<60 years old) and 6113 old participants (≥60 years old). Using PLINK (version 1.9) software, quality control was carried out, followed by logistic regression analysis with adjustments for sex, age, body mass index, depression, and manic episodes as covariates. We also built PRS prediction models using the standard clumping and thresholding method and evaluated their performance (area under the curve [AUC]) through five-fold cross-validation.

Results

Eleven independent risk loci were identified for these patients with DED at the genome-wide significance levels, including DNAJB6, MAML3, LINC02267, DCHS1, SIRPB3P, HULC, MUC16, GAS2L3, and ZFPM2. Among these, MUC16 encodes mucin family protein. The PRS model incorporated 932 and 740 genetic loci for young and old populations, respectively. A higher PRS score indicated a greater DED risk, with the top 5% of PRS individuals having a 10-fold higher risk. After integrating these covariates into the PRS model, the area under the receiver operating curve (AUROC) increased from 0.509 and 0.537 to 0.600 and 0.648 for young and old populations, respectively, demonstrating the genetic-environmental interaction.

Conclusions

Our study prompts potential candidates for the mechanism of DED and paves the way for more personalized medication in the future.

Translational Relevance

Our study identified genes related to DED and constructed a PRS model to improve DED prediction.

The epidemiology of pediatric dry eye disease in the United States: An IRIS® registry (Intelligent Research in Sight) analysis

PURPOSE

Dry-eye disease (DED) is a chronic progressive ocular surface disorder with limited studies in the pediatric population. The Academy of Ophthalmology's IRIS® Registry was leveraged to investigate the prevalence of DED in the pediatric population (PDED, patients <18 years old) and the demographic differences of DED between pediatric and adult patients (ADED).

METHODS

Retrospective cohort study. Patients with DED between January 1st, 2013 and December 31st, 2019 (N = 4,795,979) were included. Descriptive statistics, Pearson's chi-squared tests and two-sample proportions tests were conducted to compare key demographic distributions between the ADED and PDED cohorts.

RESULTS

The average age at onset for ADED patients was 61.06 (±14.75) years and for PDED patients was 12.51 (±3.86). The overall tests for independence and the individual tests of proportions of each category were statistically significant for all demographic characteristics (p < 0.001). Characteristics with the largest discrepancies between patients of PDED and the IRIS Registry pediatric patient pool (PIRIS) included female sex (58.08 % vs. 50.60 %), male sex (41.58 % vs. 48.78 %) and Asian race (6.02 % vs. 3.11 %) respectively. Within the PDED cohort, females were at higher risk of PDED (58 % vs. 42 %). PDED was more prevalent in children with refractive errors (76 %) and eyelid/conjunctival disorders (41 %). Characteristics with the largest discrepancies between PDED and ADED patients included female sex (58.08 % vs. 68.12 %), male sex (41.58 % vs. 31.55 %) and Caucasian race (50.24 % vs. 67.06 %) respectively.

CONCLUSIONS

Significant differences in the PDED cohort are demonstrated in this study. PDED was more prevalent in the female sex and Caucasian race compared to PIRIS and was more commonly associated with refractive errors and eyelid/conjunctival disorders.

United States Regulatory Approval of Topical Treatments for Dry Eye

PURPOSE

To report the heterogeneity in methodology of clinical trials submitted to the US Food and Drug Administration (FDA) for approval of topical dry eye treatments.

DESIGN

Comparative analysis of clinical trials' methods.

METHODS

We reviewed the online, publicly available FDA database, application review files, ClinicalTrials.gov registry records, and journal articles for each FDA-approved topical dry eye treatment. For each trial, we extracted information about the study, patient demographics, treatment names and doses, sample size in each arm, and the measurement instrument in a systematic fashion.

RESULTS

Fourteen trials were included that assessed 5 topical treatments for dry eye (cyclosporine 0.05%, cyclosporine 0.09%, lifitegrast 5%, and loteprednol 0.25% eye drops and varenicline 0.03-mg nasal spray). Median treatment duration was 12 weeks (range, 2-24 weeks). In all trials, treatments, including varying concentrations of the same treatment, were compared with vehicle. Twelve trials (85.7%) evaluated a primary clinician-measured clinical sign, and 10 trials (71.4%) evaluated a primary patient-reported symptom. Corneal staining was the most frequently evaluated clinical sign primary outcome, reported in half (6 of 12) of the trials, and was graded using 4 different scoring systems. Conjunctival staining, conjunctival hyperemia, and tear production were each measured using 2 different scoring systems. Ocular discomfort, the only patient-reported symptom primary outcome, was measured using 5 different instruments.

CONCLUSION

A variety of outcome measures were used in these clinical trials. Clinically meaningful dry eye outcome measures and standardized measurements can optimize the assessment of and comparison of therapeutic benefits.

Dry eye disease in astronauts: a narrative review

Long-duration spaceflight can have adverse effects on human health. One of the most common ocular conditions experienced by astronauts is dry eye disease (DED). Symptoms of DED include feelings of eye irritation, eye strain, foreign body sensation and blurred vision. Over 30% of International Space Station expedition crew members reported irritation and foreign body sensation. We reviewed the current literature on the prevalence and mechanisms of DED in astronauts and its potential implications for long-duration spaceflight, including the influence of environmental factors, such as microgravity and fluid shift on tear film physiology in space. DED has negative effects on astronaut performance, which is why there is a need for further research into the pathophysiology and countermeasures. As an in-flight countermeasure, neurostimulation seems to be among the most promising options.

A comparative review of evaporative dry eye disease and meibomian gland dysfunction in dogs and humans

Dry eye disease is a complex ophthalmic disorder that consists of two main subtypes, aqueous deficient dry eye (ADDE) and evaporative dry eye disease (EDED). Due to the complex underlying physiology, human dry eye disease can be difficult to model in laboratory animal species. Thus, the identification and characterization of a spontaneous large animal model of dry eye disease is desirable. Dogs have been described as an ideal spontaneous model of ADDE due to the similar pathophysiology between dogs and humans. Recently, EDED and meibomian gland dysfunction (MGD) have been increasingly recognized and reported in dogs. These reports on EDED and MGD in dogs have identified similarities in pathophysiology, clinical presentations, and diagnostic parameters to humans with the comparable disorders. Additionally, the tests that are used to diagnose EDED and MGD in humans are more easily applicable to dogs than to laboratory species due to the comparable globe sizes between dogs and humans. The reported response of dogs to EDED and MGD therapies are similar to humans, suggesting that they would be a valuable preclinical model for the development of additional therapeutics. Further research and clinical awareness of EDED and MGD in dogs would increase their ability to be utilized as a preclinical model, improving the positive predictive value of therapeutics for EDED and MGD in both humans and dogs.

What Are the Dry Eye Questionnaires Available in the Scientific Literature Used for? A Scoping Review

PURPOSE

Dry eye disease (DED) is a frequent chronic ophthalmic condition. Its diagnosis includes tests and patient reported outcomes (PRO) questionnaires. Although many PRO dry eye questionnaires (PRO-DEQs) are available, they differ greatly from each other and not all have been validated. The purpose of this study was to retrieve the PRO-DEQs present in the scientific literature by performing a descriptive analysis of them and identifying those with known validity and reliability characteristics and to perform a descriptive analysis of the geographic area, year of publication, and characteristics of the target population of the clinical studies that have used validated PRO-DEQs.

DESIGN

Scoping review of the literature.

METHODS

Searches were conducted in PubMed to retrieve PRO-DEQs published up to July 2018 and written in English, French, Italian or Spanish.

RESULTS

One thousand six hundred two records were identified and 973 were included in the final analysis. Of these, 56 provided information on the design and validation of PRO-DEQs and 49 PRO-DEQs were identified. Twenty-two PRO-DEQs were validated (17 original and 5 modified) and 27 had no associated design, validity, and reliability studies. Most of the validated PRO-DEQs were designed in English, the number of items varies from 1 to 57, the dimensions are generally not specified, and they are self-administered. The greatest use of validated PRO-DEQs in clinical studies has been in Asia since 2010, with the Ocular Surface Disease Index being the most used. These questionnaires have been used mostly in adults, retired professionals, and people with visual diseases to diagnose DED.

CONCLUSIONS

This study aims to encourage the use of validated PRO-DEQs to guarantee the quality of the results obtained and the comparability and replicability among studies.

Differential response to topical lubrication in patient with dry eye disease, based on age

BACKGROUND

To compare the Ocular surface disease index (OSDI) score, Schirmer I test (SIT), fluorescein break up time (FBUT) and fluorescence staining (FLCS) score of dry eye patients at different ages.

METHODS

90 eyes of 90 patients with mild to moderate dry eye from September 2020 to September 2021 were retrospectively included and were divided into young group (20-39 years, n = 29), middle-age group (40-59 years, n = 30), and elder group (> 60 years, n = 31). Patients were given a 28-day topical lubricating ocular surface and repair-promoting drugs combined with local physical therapy. Patients were followed up at 7, 14 and 28 days. The OSDI score, SIT, FBUT and FLCS score were examined.

RESULTS

There were differences between the OSDI score in three groups at each time point (all P < 0.001). SIT were different among the three groups (F = 350.61, P < 0.001), and a time effect was found (F = 80.87, P < 0.001). SIT at 14 and 28 days after treatment in middle-age and elder groups were lower than young group (all P < 0.001). SIT at 7, 14 and 28 days in elder group were lower than middle-age group (all P < 0.001). FLCS score was lower at 28 days than other time points (all P < 0.001).

CONCLUSION

Dry eye patients are given a 28-day topical lubricating ocular surface and repair-promoting drugs combined with local physical therapy, which can promote tear secretion, film stability, and the recovery of corneal integrity. Age affects the treatment effect of mild to moderate dry eye, among which tear secretion is the most significant.

Predicting demographics from meibography using deep learning

This study introduces a deep learning approach to predicting demographic features from meibography images. A total of 689 meibography images with corresponding subject demographic data were used to develop a deep learning model for predicting gland morphology and demographics from images. The model achieved on average 77%, 76%, and 86% accuracies for predicting Meibomian gland morphological features, subject age, and ethnicity, respectively. The model was further analyzed to identify the most highly weighted gland morphological features used by the algorithm to predict demographic characteristics. The two most important gland morphological features for predicting age were the percent area of gland atrophy and the percentage of ghost glands. The two most important morphological features for predicting ethnicity were gland density and the percentage of ghost glands. The approach offers an alternative to traditional associative modeling to identify relationships between Meibomian gland morphological features and subject demographic characteristics. This deep learning methodology can currently predict demographic features from de-identified meibography images with better than 75% accuracy, a number which is highly likely to improve in future models using larger training datasets, which has significant implications for patient privacy in biomedical imaging.

Hypolacrimia and Alacrimia as Diagnostic Features for Genetic or Congenital Conditions

As part of the lacrimal apparatus, the lacrimal gland participates in the maintenance of a healthy eye surface by producing the aqueous part of the tear film. Alacrimia and hypolacrimia, which are relatively rare during childhood or young adulthood, have their origin in a number of mechanisms which include agenesia, aplasia, hypoplasia, or incorrect maturation of the gland. Moreover, impaired innervation of the gland and/or the cornea and alterations of protein secretion pathways can lead to a defective tear film. In most conditions leading to alacrimia or hypolacrimia, however, the altered tear film is only one of numerous defects that arise and therefore is commonly disregarded. Here, we have systematically reviewed all of those genetic conditions or congenital disorders that have alacrimia or hypolacrimia as a feature. Where it is known, we describe the mechanism of the defect in question. It has been possible to clearly establish the physiopathology of only a minority of these conditions. As hypolacrimia and alacrimia are rare features, this review could be used as a tool in clinical genetics to perform a quick diagnosis, necessary for appropriate care and counseling.

The association between visual display terminal use and dry eye: a review

BACKGROUND

Dry eye disease (DED) is a multifactorial disease of the tear film and ocular surface. It causes ocular symptoms, reduced quality of life and a considerable economic burden on society. Prolonged use of visual display terminals (VDTs) has been suggested as an important risk factor for DED.

PURPOSE

This review aims to study the association between DED and VDT use with an emphasis on the prevalence of DED among VDT users and harmful daily duration of VDT use.

METHODS

A PubMed search was conducted and yielded 57 relevant articles based on a set of inclusion and exclusion criteria. The studies were subclassified according to study design.

RESULTS

The far majority of the studies showed an association between VDT use and DED or DED-related signs and symptoms. The prevalence of definite or probable DED in VDT and office workers ranged from 26% to 70%, with as few as 1-2 hr of VDT exposure per day being associated with DED.

CONCLUSION

VDT use is strongly associated with DED. VDT-associated DED is prevalent, but the exact prevalence needs to be further elucidated using standardized DED diagnosis criteria. Furthermore, a safe lower limit of daily VDT use has yet to be established. More research is needed on the effect of digitalization and digital transformation, which are particularly high during the time of the COVID-19 pandemic.

The impact of contact lenses on meibomian gland morphology

Despite years of experience with contact lenses, controversy remains as to whether contact lenses adversely impact the meibomian glands (MG). This review summarizes the present body of evidence, showing that contact lens wear is associated with alterations in MG morphology (up to 80% higher gland atrophy compared to non-wearers) and qualitative changes in MG secretion. Key factors such as duration of contact lens wear, contact lens type (e.g., soft vs. rigid), edge design, and material modulus of elasticity are discussed in relation to the extent of MG morphological changes, the quality of MG secretion and other ocular surface parameters. Longitudinal studies of sufficient statistical power are needed to better understand how contact lens wear affects the MG, risk factors, and the clinical sequelae of these changes.

Systemic, environmental and lifestyle risk factors for dry eye disease in a mediterranean caucasian population

OBJECTIVES

To assess systemic, environmental and lifestyle risk factors for dry eye disease (DED) in a Mediterranean Caucasian population.

METHODS

A cross-sectional study was performed on 120 Caucasian participants aged between 18 and 89 years (47.0 ± 22.8 years). Medical history, information regarding environmental conditions and lifestyle, Ocular Surface Disease Index, Dry Eye Questionnaire-5, non-Invasive (Oculus Keratograph 5 M) breakup time, tear film osmolarity and ocular surface staining parameters were assessed in a single clinical session to allow DED diagnosis based on the guidelines of the Tear Film and Ocular Surface Society Dry Eye Workshop II Diagnostic Methodology Report. A multivariate logistic regression model was constructed including those variables with a p-value less than 0.15 in the univariate analysis.

RESULTS

A prevalence of 57.7 % for DED was found. No age differences were found between those with and without DED (U = 1886.5, p = 0.243). Nevertheless, the DED group had more females (X² = 7.033, p = 0.008). The univariate logistic regression identified as potential risk factors for DED the following: female sex, sleep hours per day, menopause, anxiety, systemic rheumatologic disease, use of anxiolytics, daily medication, ocular surgery, poor diet quality, more ultra-processed food in diet, not drinking caffeine and hours of exposure to air conditioning per day. Multivariate logistic regression revealed that hours of sleep per day, menopause and use of anxiolytics were independently associated with DED (p ≤ 0.026 for all).

CONCLUSIONS

DED is associated with systemic, environmental and lifestyle risk factors. These findings are useful to identify potentially modifiable risk factors, in addition to conventional treatments for DED.

Quantitative analysis of morphological and functional features in Meibography for Meibomian Gland Dysfunction: Diagnosis and Grading

BACKGROUND

To explore the performance of quantitative morphological and functional analysis in meibography images by an automatic meibomian glands (MGs) analyser in diagnosis and grading Meibomian Gland Dysfunction (MGD).

METHODS

A cross-sectional study collected 256 subjects with symptoms related to dry eye and 56 healthy volunteers who underwent complete ocular surface examination was conducted between January 1, 2019, and December 31, 2020. The 256 symptomatic subjects were classified into MGD group (n = 195) and symptomatic non-MGD group (n = 61). An automatic MGs analyser was used to obtained multi-parametric measurements in meibography images including the MGs area ratio (GA), MGs diameter deformation index (DI), MGs tortuosity index (TI), and MGs signal index (SI). Adjusted odds ratios (ORs) of the multi-parametric measurements of MGs for MGD, and the area under the receiver operating characteristic (AUC-ROC) curves of multi-parametric measurements for MGD diagnosing and grading were conducted.

FINDINGS

When consider age, sex, ocular surface condition together, the estimated ORs for DI was 1.62 (95% CI, 1.29-2.56), low-level SI was 24.34 (95% CI, 2.73-217.3), TI was 0.76(95% CI, 0.54-0.90), and GA was 0.86 (95% CI, 0.74-0.92) for MGD. The combination of DI-TI-GA-SI showed an AUC = 0.82 (P < 0.001) for discriminating MGD from symptomatic subjects. The DI had a higher AUC in identifying early-stage MGD (grade 1-2), while TI and GA had higher AUCs in moderate and advanced stages (grade 3-5). Merging DI-TI-GA showed the highest AUCs in distinguish MGD severities.

INTERPRETATION

The MGs area ratio, diameter deformation, tortuosity and signal intensity could be considered promising biomarkers for MGD diagnosis and objective grading.

FUNDING

This work was supported by the Key-Area Research and Development Program of Guangdong Province (No. 2019B010152001), the National Natural Science Foundation of China under Grant (81901788) and Guangzhou Science and Technology Program (202002030412).

Reliability and clinical applicability of a novel tear film imaging tool

PURPOSE

The aim of our research was to investigate the reliability and clinical applicability of a modern tear film imaging tool by comparing the inter- and intragrader difference. The further goal was to compare the non-invasive tear break-up time (NIBUT) measured with the LacryDiag® device with traditional tear film break-up time (TBUT).

METHODS

Comprehensive ophthalmological examination was performed, including LacryDiag® (Quantel Medical, France) (lower tear meniscus height measuring (LTMH), superior and inferior eyelid meibography (MeibS MeibI), interferometry (INT), NIBUT), slit lamp examination, and TBUT. Two independent, well-trained graders selected and analyzed the LTMH, MeibI, MeibS, and INT. The second grader reanalyzed the data 1 month later. Intra- and inter-examiner reliabilities were evaluated using intraclass correlation coefficients (ICC), while for categorical variable, Cohen's kappa statistics were provided. The Bland-Altman plot was used for visualization of the agreement between measurements.

RESULTS

Fifty healthy volunteers were examined. For LTMH both the inter- and intragrader variabilities were excellent. Between two graders, the ICC of MeibI was poor; however, between two graders, the ICC of MeibS was good, and the intragrader variability in MeibI and MeibS was excellent. For the INT, both intra- and intergrading were in fair and moderate agreement, although the intragrader agreement was higher. Comparing the NIBUT and TBUT, the agreement was slight.

CONCLUSION

Based on our results, examination of a patient during follow-up should be performed by the same examiner, because of the slight agreement. The LacryDiag® is a non-invasive, easy-to-use device, which can examine the tear film and save the recordings for easier follow-up.

Demographic and lifestyle risk factors of dry eye disease subtypes: A cross-sectional study

PURPOSE

To evaluate demographic and lifestyle factors associated with aqueous deficient and evaporative dry eye disease.

METHODS

A total of 1125 general public visitors (707 females, mean ± SD age, 33 ± 21, range 5-90 years) at the Royal Society Summer Science Exhibition were recruited in a cross-sectional study. A demographic and lifestyle factor questionnaire was administered, and dry eye symptomology (DEQ-5 score), ocular surface characteristics (conjunctival hyperaemia, and infrared meibography), and tear film parameters (tear meniscus height, non-invasive breakup time, and lipid layer grade) were evaluated for the left eye of each participant within a single session. The diagnostic criteria for dry eye disease subtypes were adapted from the rapid non-invasive dry eye assessment algorithm.

RESULTS

Overall, 428 (38%) participants fulfilled the diagnostic criteria for dry eye disease, 161 (14%) with aqueous deficient dry eye disease, and 339 (30%) with evaporative dry eye disease. Multivariate logistic regression demonstrated that advancing age, female sex, reduced sleep duration, higher psychological stress, and poorer self-perceived health status were independently associated with aqueous deficient dry eye disease (all p < 0.05). Significant risk factors for evaporative dry eye disease included advancing age, East and South Asian ethnicity, contact lens wear, increased digital device screen exposure, higher psychological stress, and poorer self-perceived health status (all p < 0.05).

CONCLUSIONS

Both subtypes of dry eye disease were associated with several unique and shared demographic and lifestyle factors. The findings of this study could inform future research design investigating the utility of targeted screening and risk factor modification for the prevention and management of dry eye disease.

Therapeutic potential of castor oil in managing blepharitis, meibomian gland dysfunction and dry eye

The multifactorial pathogenesis and interrelationship of blepharitis, meibomian gland dysfunction and dry eye disease poses challenges to any therapeutic approach. Current treatments are mostly palliative, with success limited by perceived inefficacy and poor patient compliance. Castor oil, a natural derivative of the Ricinus communis plant, is widely used as an emollient in cosmetics and personal care products, drug delivery systems and wound dressings. Castor oil is deemed safe and tolerable, with strong anti-microbial, anti-inflammatory, anti-nociceptive, analgesic, antioxidant, wound healing and vaso-constrictive properties. Its main constituent, ricinoleic acid, has a bipolar molecular structure that promotes the formation of esters, amides and polymers. These can supplement deficient physiological tear film lipids, enabling enhanced lipid spreading characteristics and reducing aqueous tear evaporation. Studies reveal that castor oil applied topically to the ocular surface has a prolonged residence time, facilitating increased tear film lipid layer thickness, stability, improved ocular surface staining and symptoms. This review summarises the properties, current uses of, and therapeutic potential of castor oil in managing ocular surface disease. The biochemical, medicinal actions of castor oil are explored from the perspective of ocular surface pathology, and include microbial and demodectic over-colonisation, inflammatory and oxidative processes, as well as clinical signs and symptoms of dryness and discomfort.

Modifiable lifestyle risk factors for dry eye disease

PURPOSE

To examine the association between modifiable lifestyle factors and dry eye disease.

METHODS

Three hundred and twenty-two community residents (186 females, 136 males; mean ± SD age, 41 ± 22 years) with no major systemic or ophthalmic conditions (other than dry eye disease) were recruited in a cross-sectional study. A lifestyle factor questionnaire was administered, and dry eye symptomology, ocular surface characteristics, and tear film quality were evaluated for each participant within a single clinical session, in accordance with the global consensus recommendations of the TFOS DEWS II reports.

RESULTS

A total of 111 (34 %) participants fulfilled the TFOS DEWS II diagnostic criteria for dry eye disease. Multivariate regression analysis demonstrated that advancing age, female sex, East Asian ethnicity, and increased digital screen exposure time were positive risk factors for dry eye disease (all p < 0.05), while increased caffeine consumption was a protective factor (p = 0.04).

CONCLUSIONS

Increased digital screen exposure time and reduced caffeine consumption were modifiable lifestyle factors associated with higher odds of dry eye disease. These findings might contribute to informing the design of future prospective research investigating the efficacy of preventative intervention and risk factor modification strategies.

Ageing and the natural history of dry eye disease: A prospective registry-based cross-sectional study

PURPOSE

To investigate the impact of ageing on ocular surface parameters, and empirically determine optimal prognostic cut-off ages for clinical markers of dry eye disease, aqueous tear deficiency, and meibomian gland dysfunction.

METHODS

A total of 1331 community residents (785 females, 546 males; mean ± SD age, 38 ± 19 years) were recruited in a prospective registry-based cross-sectional study. Dry eye symptomology, ocular surface characteristics, and tear film quality were evaluated for each participant within a single clinical session, in accordance with the global consensus recommendations of the TFOS DEWS II reports.

RESULTS

Multivariate regression analysis demonstrated positive associations between ageing and clinical markers of dry eye disease (all p ≤ 0.001). The Youden-optimal prognostic cut-off ages for signs of meibomian gland dysfunction occurred during the third decade of life (24-29 years); the optimal predictive ages for lid wiper epitheliopathy, tear film instability, hyperosmolarity, and dry eye symptoms occurred during the fourth decade of life (31-38 years); while the optimal prognostic thresholds for signs of aqueous tear deficiency and ocular surface staining occurred in the fifth and sixth decades of life (46-52 years).

CONCLUSIONS

Advancing age is a significant risk factor for dry eye disease, which represents a growing public health concern with the ageing population worldwide. Signs of meibomian gland dysfunction appeared earlier in the natural history of disease progression, and the brief delay prior to the development of other clinical dry eye signs might represent a window of opportunity for preventative interventions in the young adult age group.

Ocular Demodex: a systematic review of the clinical literature

PURPOSE

There is increasing clinical and research interest in the potential contribution of Demodex to ocular surface disease. The aim of this systematic review was to summarise and synthesise current clinical evidence relating to the aetiology, diagnosis and treatment of ocular Demodex.

RECENT FINDINGS

A comprehensive literature search was performed in OVID Medline, OVID Embase, and clinical trial registries, for studies published between 1990 and August 2019, examining Demodex on the ocular surface. The review included primary clinical research studies and systematic reviews of primary clinical research studies, where Demodex was considered in the context of the ocular surface and/or adnexa. Studies were categorised using the National Health and Medical Research Council evidence hierarchy. Risk of bias assessment was performed using validated tools for studies categorised as providing Level I or II evidence. A total of 87 studies were eligible for inclusion, including two systematic reviews. Most studies (60%) were observational, describing the prevalence of ocular Demodex in different clinical populations. There was a high degree of variability in the epidemiological data derived from cross-sectional aetiology studies. There was mostly consistent evidence to support an association between ocular Demodex and chronic blepharitis. Seven diagnostic test-accuracy studies were identified, which considered a range of techniques, including slit lamp examination for cylindrical eyelash collarettes and/or eyelash manipulation techniques, light microscopic evaluation of epilated eyelashes and in vivo confocal microscopy. There is currently no accepted gold-standard diagnostic method for ocular Demodex. For intervention studies, there was one systematic review, 11 published randomised trials, six trial registry entries, and nine case series. Despite a number of recent trials, the appropriate treatment regimen for ocular Demodex (including the optimal criteria and timing of an intervention) is not clearly established.

CONCLUSIONS

This comprehensive narrative synthesis has captured the landscape of clinical evidence relating to the prevalence, aetiology, diagnosis and treatment of ocular Demodex. There remain opportunities to enhance understanding of its role in ocular surface disease, best diagnostic approaches and optimal treatment protocols.