Impact of Air Pollution and Weather on Dry Eye

Associations between air pollution and daily outpatient visits for dry eye disease and the effect modification of temperature

BACKGROUND

Dry eye disease (DED) is one of the most common ocular surface disorders caused by various contributors. Air pollutants are considered a risk factor for ocular surface diseases. We aimed to investigate the associations between air pollutants (PM2.5, PM10, NO2, SO2, CO and O3) and PM2.5 constituents and daily outpatient visits for DED, as well as the modifying effect of temperature on the associations.

METHODS

Daily data on DED outpatient visits and environmental variables during 2014-2019 were collected in Hangzhou, China. Distributed lag nonlinear models (DLNM) combined with time-stratified case-crossover design were utilized to evaluate the effects of air pollutants and PM2.5 constituents on DED daily outpatient visits during 0‒3 lag days. Furthermore, we also estimated the modification effect of temperature stratified by median. The attributable fraction (AF) of air pollutants and PM2.5 constituents on DED outpatient visits were quantified. Stratified analyses of gender, age, and seasons were conducted to assess vulnerable population characteristics and high-risk periods.

RESULTS

Every interquartile range increase in PM2.5, PM10, NO2, SO2 and CO concentration were significantly associated with daily DED cases. The AF were 6.42% (95% CI: 1.09%, 11.58%), 8.00% (2.60%, 13.60%), 18.65% (11.52%, 25.21%), 10.82% (3.92%, 17.24%) and 12.28% (0.23%, 22.86%), respectively. For PM2.5 constituents, NO3- and NH4+ were associated with DED, with AF of 4.34% (0.21%, 8.11%) and 4.84% (0.18%, 9.09%), respectively. The effects of air pollution were significant in low-temperature level for PM2.5, PM10, NO2, SO2, and CO; while the effects were statistically insignificant in high-temperature level. Subgroup analyses indicated significant associations were present in winter and among patients aged 21-40 but insignificant in other seasons and age groups.

CONCLUSION

Our results revealed that air pollutants were associated with DED outpatient visits. Low temperatures might increase the hazardous effects of air pollution. Besides, individuals aged 21-40 were vulnerable to air pollution, and winter was the high-risk period.

CLINICAL TRIAL NUMBER

Not applicable.

The Impact of Home Interventions on Dry Eye Disease (DED) Symptoms and Signs in United States Veterans

BACKGROUND

The indoor environment can contribute to dry eye disease (DED) risk, but the effects of environmental modifications on disease are still uncertain. This study evaluated the effect of home interventions that modify the indoor environment on DED symptoms and sign severity.

METHODS

The prospective study consisted of two visits (6 ± 1 months apart). At each home visit, indoor environmental conditions (temperature, humidity, and airborne particulate matter) were monitored and at each clinical visit, DED symptoms and signs were examined. After the first visit, all participants received a report of their home air quality and 10 recommendations to improve their home environment. At the 6-month visit, participants indicated which interventions they implemented.

RESULTS

A total of 99 subjects participated in the clinical evaluation and home monitoring at baseline and six-month follow-up. Their mean age was 61 years, and 26% identified as Hispanic. Most had mild or greater DED symptoms (5-Item Dry Eye Questionnaire, DEQ5 ≥ 6), with an average DEQ5 score of 10.49 ± 5.51 at baseline. In total, 77% (n = 76) implemented ≥1 intervention with home ventilation (42.4%), air conditioner filter change (36.4%), and exhaust fan use (31.3%) being the most frequent. Overall, with every intervention implemented, tear osmolarity (change from baseline to 6 months) declined by 2% (log-transformed β = 0.02; 95% confidence interval (CI) = 0.00-0.03; p < 0.05), and Meibomian gland (MG) plugging declined by 14% (log-transformed β = 0.14; CI = 0.05-24; p < 0.05). Specific interventions had specific impacts on DED signs and symptoms. For example, osmolarity declined by a greater degree in those that implemented home ventilation, while DED symptoms improved to a greater degree in those that utilized indoor plants compared to those that did not implement these interventions.

CONCLUSIONS

When provided with an objective report of home environmental conditions and remediation strategies, most participants voluntarily implemented low-cost home interventions, which reduced the severity of select DED symptoms and signs.

Climate Determinants of Keratoconus: Insights From a Systematic Review of Prevalence

Purpose

The reported prevalence of keratoconus varies widely worldwide, but the causes of this variation are not well understood. We therefore aimed to explore the potential impact of local climate variables on keratoconus prevalence.

Methods

The worldwide prevalence of clinical keratoconus in the general population was systematically reviewed. In each eligible prevalence area, four climate variables deemed possibly relevant to keratoconus were assessed: daily maximum temperature, relative humidity, ultraviolet radiation, and wind speed. Climate variables were calculated using worldwide gridded climate datasets from the European Center of Medium-Range Weather Forecasts. Population density weighting was applied to enhance exposure accuracy. The average of each climate variable was calculated over the 10 years preceding data collection of each study. The potential impact of those climate variables was investigated using multiple linear regression adjusted for the gross domestic product per capita (based on purchasing power parity) with the natural logarithm of prevalence as the outcome variable.

Results

Sixteen eligible studies were identified. After filtering to retain one prevalence estimate per region, 11 studies including datapoints from 61 areas were analyzed. The median (interquartile range) prevalence of keratoconus was 0.10% (0.07%-0.19%). Multiple regression revealed a significant negative association between humidity and keratoconus prevalence (β = -0.03; 95% confidence interval, -0.06 to -0.01; P = 0.004). In contrast, the other analyzed climate variables were not significantly associated with keratoconus prevalence.

Conclusions

Using global gridded climate maps, we observed a significant and biologically plausible link between low humidity and keratoconus. This suggests that humidification could benefit patients and at-risk groups.

Association between traffic-related air pollution and risk of outpatient visits for dry eye disease in a megacity along the subtropical coast in South China

BACKGROUND

Traffic-related air pollution especially in highly socioeconomically developed megacity is usually considered as a severe problem leading to inevitable adverse health outcomes. This study aimed to investigate the associations between traffic-related air pollutants with risk of dry eye disease (DED) outpatient visits in a megacity (Guangzhou) along the subtropical coast in South China.

METHODS

Daily data on DED outpatient visits and environmental variables from 1 January 2014 to 31 December 2020 in Guangzhou were obtained. A time-series study using a quasi-Poisson generalized linear model (GLM) combined with distributed lag non-linear model (DLNM) was adopted. Subgroup analyses stratified by age, gender, and season were conducted.

RESULTS

Totally, 27, 828 DED cases were identified during the study period including 2557 days. Daily number of outpatient visits for DED ranged from 0 to 41. An increase of 10 μg/m3 in PM2.5, NO2 and SO2 concentration was associated with 3.1%, 5.9% and 17.4% increase in the risk of DED outpatient visits, respectively (RRPM2.5 = 1.031, 95%CI: 1.004-1.059, lag 0-11 day; RRNO2 = 1.059, 95% CI: 1.027-1.092, lag0-14 day; RRSO2 = 1.174, 95% CI: 1.036-1.330, lag0-13 day). Subgroup analyses indicated that the effects of PM2.5 exposure on the risk of DED outpatient visits remained significant in aged < 60 years (RR max = 1.008, 95% CI: 1.003-1.013, lag0 day) and the effects of SO2 exposure on the DED outpatient visits risk remained significant in the females (RR max = 1.025, 95% CI: 1.006-1.044, lag0 day). The associations of PM2.5 (RR = 1.010, 95% CI: 1.003-1.016, lag0 day) and SO2 (RR = 1.030, 95% CI: 1.003-1.058, lag14 day) exposure with DED outpatient visits risk remained significant in warm seasons, whereas NO2 (RR = 1.006, 95% CI: 1.002-1.009, lag14 day) exposure was significantly associated with DED outpatient visits in cold seasons. The associations of PM2.5 (first visit, RR = 1.006, 95% CI: 1.001-1.011, lag0 day; re-visit, RR = 1.002, 95% CI: 1.000-1.005, lag6 day), NO2 (first visit, RR = 1.006, 95% CI: 1.001-1.012, lag0 day; re-visit, RR = 1.007, 95% CI: 1.002-1.012, lag0 day), and SO2 (first visit, RR = 1.023, 95% CI: 1.002-1.044, lag0 day; re-visit, RR = 1.023, 95% CI: 1.000-1.045, lag0 day) exposure with risk of DED outpatient visits were significant for both first- and re-visits.

CONCLUSIONS

Our study revealed that short-term exposure to PM2.5, NO2 and SO2 were positively associated with risk of DED outpatient visits, especially for the youngers, females and during warm seasons, providing evidence for making public health policy to improve life quality in developed megacity.

Bilateral improvement in age-related macular degeneration following unilateral Aflibercept injection

BACKGROUND

The "fellow-eye effect" in anti-vascular endothelial growth factor (anti-VEGF) therapy is a rare phenomenon, particularly with aflibercept. This case report documents the first instance of this effect in Pakistan, highlighting its significance in a resource-limited setting where recent regulatory changes have restricted treatment options for age-related macular degeneration (AMD).

CASE PRESENTATION

A 62-year-old male presented with bilateral central vision loss due to neovascular AMD. Optical Coherence Tomography revealed serous subretinal fluid in both eyes. Due to financial constraints, only the right eye received a single 2 mg intravitreal aflibercept injection. Remarkably, at the four-week follow-up, both eyes showed significant improvement. Visual acuity improved from 6/12 to 6/9 in the treated right eye and from 6/15 to 6/12 in the untreated left eye. OCT scans demonstrated bilateral resorption of subretinal fluid. At three months, complete fluid resorption was observed in both eyes, with visual acuity improving to 6/6 bilaterally.

CONCLUSIONS

This case underscores the potential of the "fellow-eye effect" in anti-VEGF therapy, particularly with aflibercept, in treating bilateral AMD. It highlights a possible strategy for optimizing treatment regimens and reducing costs in resource-limited settings. However, it also raises concerns about systemic absorption and potential risks. The findings emphasize the need for further research on the pharmacokinetics of anti-VEGF agents, personalized treatment plans, and alternative therapies. This case is particularly significant in the context of Pakistan's recent ban on bevacizumab, underscoring the urgent need for accessible and affordable AMD treatments in developing countries.

Effects of Stage Lighting on Visual Comfort at Summer Festivals: A Study in Portugal

Background: The primary objective of this study was to assess the visual comfort and health impacts of stage lighting on attendees at summer festivals. Specifically, the study aimed to evaluate the effects of different types of lighting, including natural, artificial, and stage lighting, on symptoms such as glare, eye strain, tearing, and temporary vision loss. Methods: A survey was conducted among attendees of various summer festivals in Portugal. Participants were asked about their perceptions of lighting conditions and the related visual symptoms they experienced. The survey addressed sensitivity to different types of lighting, the impact of smoke on eye discomfort, and potential strategies for improving visual comfort. Data analysis was performed using IBM SPSS® v.27 to explore trends and correlations. Results: The findings indicated that cooler stage lighting was associated with a higher incidence of glare, with male participants reporting greater discomfort than females. However, there were no significant differences between gender, age, or refractive status when examining the effects of smoke on symptoms like dry eyes and tearing. Notably, participants aged 19-25 experienced more frequent tearing under stage lighting. Key recommendations included the use of high-quality LED lighting, supported by 44.81% of respondents, and the provision of low-light areas for visual rest, which 37.66% of participants deemed essential. Additional suggestions included minimizing intermittent lights and increasing the awareness of vision protection to improve visual comfort. Conclusions: This study highlights the importance of optimizing stage lighting to enhance visual comfort at summer festivals. Festival organizers are encouraged to implement high-quality LED lighting and directional lighting technologies, as well as to create low-light zones for visual rest. Reducing the use of flashing or intermittent lights and providing eye protection information to attendees are also crucial steps to improve the overall visual experience and safeguard eye health at large-scale events.

Association Between Particulate Matter Pollutants and Ophthalmology Visits for Ocular Surface Irritation and Allergy

Background

The World Health Organization has declared climate change to be "the single biggest health threat facing humanity", yet there are limited studies on the impact of climate change-related air pollution on ocular health.

Objective

To explore associations between ocular surface irritation and allergy-related daily outpatient office visits with daily ambient particulate matter (PM) levels in the Denver Metropolitan Area.

Methods

Daily visit counts of ophthalmology outpatient offices were obtained from an academic health center (October 1st, 2015 to January 27th, 2023). Daily ambient average concentrations of PM ≤ 10 µm in diameter (PM10) and 2.5 micrometers or less in diameter (PM2.5) were obtained. Data were analyzed using distributed lag nonlinear models while accounting for the cumulative lagged effects of PM10 and PM2.5 for visits. Modifications due to temperature were assessed using stratified models.

Results

There were 144,313 ocular surface irritation and allergy visits to ophthalmic clinics during the study period. Daily visit counts increased with increasing daily ambient PM10 and PM2.5 concentrations. Five-day cumulative ambient PM10 concentrations at 80, 90, 100, and 110 µg/m3 showed higher rate ratios at each level from 1.77 (95% CI: 1.71, 1.84) at concentration of 80 to 2.20 (95% CI: 2.09, 2.30) for concentration of 110 µg/m3. Similarly, the visit rate ratios increased as the daily PM2.5 concentration increased, but this gradient effect was not significantly higher as the concentration increased. The effect of PM10 was higher on days when the temperature was below the average. Temperature did not affect the association between daily visit counts and PM2.5.

Conclusion

This study found that ambient PM increased the rate of ophthalmology visits due to ocular surface irritation and allergies. Most importantly, this association increased in magnitude with higher ambient PM concentrations. Additional studies are required to fully understand the effects of climate change-related stressors on ocular health.

Understanding the Dry Eye Disease-Related Symptoms in South America: Prevalence and Associated Factors-A Systematic Review

Background/Objectives: Dry eye disease is a leading cause of ophthalmologic consultations worldwide and can significantly impact quality of life. While global prevalence rates vary widely, data specific to South America are limited. This systematic review aims to describe and analyze the prevalence and associated factors of dry eye disease-related symptoms in South American populations. Methods: Following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a systematic review was conducted using databases such as PubMed, Web of Science, Scopus, and LILACS. Primary studies in English and Spanish that examined the prevalence of dry eye disease-related symptoms in South American populations and its associated factors were included without date restrictions. Studies were screened and selected based on predefined inclusion and exclusion criteria, resulting in the final inclusion of 16 studies from six South American countries. Results: This review identified significant variability in the prevalence of dry eye disease-related symptoms in South American populations in the region, ranging from 4% to 77.5%, with a mean prevalence of 39.3%. Higher prevalence rates were observed among specific groups, such as university students (58.6%) and administrative workers (57.9%). Factors associated with dry eye disease-related symptoms in South American populations included female sex, older age, prolonged screen time, insufficient sleep, and medical conditions such as hypertension, connective tissue disorders, and the use of medications like antihypertensives and antidepressants. Conclusions: The prevalence of dry eye disease-related symptoms in South American populations is notably higher than global averages, highlighting regional challenges. This study emphasizes the need for standardized diagnostic tools and comprehensive epidemiological research across South America, particularly in underrepresented countries, to inform public health strategies tailored to the specific needs of these populations.

Long-term high fructose intake reprograms the circadian transcriptome and disrupts homeostasis in mouse extra-orbital lacrimal glands

This study aims to explore the effects of long-term high fructose intake (LHFI) on the structure, functionality, and physiological homeostasis of mouse extra-orbital lacrimal glands (ELGs), a critical component of ocular health. Our findings reveal significant reprogramming of the circadian transcriptome in ELGs following LHFI, alongside the activation of specific inflammatory pathways, as well as metabolic and neural pathways. Notably, LHFI resulted in increased inflammatory infiltration, enhanced lipid deposition, and reduced nerve fiber density in ELGs compared to controls. Functional assessments indicated a marked reduction in lacrimal secretion following cholinergic stimulation in LHFI-treated mice, suggesting impaired gland function. Overall, our results suggest that LHFI disrupts lacrimal gland homeostasis, potentially leading to dry eye disease by altering its structure and secretory function. These insights underscore the profound impact of dietary choices on ocular health and highlight the need for strategies to mitigate these risks.

Influence of Environmental Factors with Clinical Signs and Symptoms in the Management of Dry Eye Disease

Background

This research aims to investigate the influence of environmental factors on the treatment efficacy of ocular lubricants in patients from urban areas with dry eye disease (DED).

Methods

A phase IV clinical trial, which included 173 patients from major cities in Mexico, was randomly assigned to use ocular lubricants four times a day for 30 days. Ocular Surface Disease Index (OSDI), noninvasive tear film break-up time (NIBUT), ocular staining, and conjunctival hyperemia (CH) among other factors like weather, and air pollution as covariates were analysed.

Results

After 30 days, OSDI score decreased by 14.8 points (p<0.001), and NIBUT increased by 2.9 seconds (p< 0.001), with longer values observed in patients recruited in autumn and winter (additional 1.8 seconds, p< 0.05) compared to those recruited in spring. Patients living in cities with cooler weather and high humidity, but low air quality had higher OSDI and conjunctival stain scores of up to 4.4 and 0.3 points, respectively, as compared to those living in cities with similar pollution and humidity levels but with higher temperatures (p-values= 0.019 and 0.050). Patients with moderate CH had an increase of up to 0.8 points in their corneal stain score (p< 0.010). We also found that ozone levels were related to the predicted changes in OSDI and NIBUT.

Conclusion

This study demonstrated the impact of environmental factors on the signs and symptoms of DED and suggests that patients residing in cities with inadequately controlled air pollution can benefit from using ocular lubricants to alleviate their symptoms.

Trial Registration

Trial is registered at clinicaltrials.gov (NCT04702776).

Association between ambient air pollution and dry eye symptoms among Chinese individuals during the COVID-19 pandemic: A national-based study

PURPOSE

To examine the association between ambient air pollution and dry eye symptoms (DES) during the COVID-19 pandemic and explore whether air pollution had increased the risk of DES to a greater extent than other risk factors.

METHODS

A nationwide cross-sectional survey was conducted from June 20, 2022 to August 31, 2022. The Ocular Surface Disease Index-6 (OSDI-6) questionnaire was used to assess the presence of DES. Logistic regression models were employed to analyze the associations between DES and air pollution variables, including air quality index (AQI), fine particulate matter (PM2.5), PM10, sulfur dioxide (SO2), carbon monoxide (CO), nitrogen dioxide (NO2), ozone (O3) and residing near industrial zones. We explored the interactions of air pollutants and other risk factors in the additive models by calculating the synergy index (SI). Standardized regression coefficients were calculated to compare the relative importance of risk factors for DES.

RESULTS

A total of 21,909 participants were included in the analysis. Residing near industrial zones was significantly correlated with a higher risk of DES (Odds ratio (OR): 1.57, 95 % confidence interval (CI): 1.38-1.79). No significant associations were found between DES and air pollutants except SO2 (OR: 1.05, 95 % CI: 1.02-1.09, per standard deviation increment in SO2 concentration). The restricted cubic spline analyses revealed a linear concentration-response relationship between SO2 and DES. The interaction analyses suggested synergetic interactions of SO2 with depression and problematic internet use. Among the risk factors, depression, anxiety and problematic Internet use contributed more to the increased risk of DES.

CONCLUSION

The association between ambient air pollutants and DES may have been mitigated during the pandemic due to increased time spent indoors. Despite this, our findings support the deleterious health impact of air pollutants. Future urban planning should plan industrial zones further away from residential areas.

Exploring the role of the ocular surface in the lung-eye axis: Insights into respiratory disease pathogenesis

Chronic respiratory diseases (CRDs) represent a significant proportion of global health burden, with a wide spectrum of varying, heterogenic conditions largely affecting the pulmonary system. Recent advances in immunology and respiratory biology have highlighted the systemic impact of these diseases, notably through the elucidation of the lung-eye axis. The current review focusses on understanding the pivotal role of the lung-eye axis in the pathogenesis and progression of chronic respiratory infections and diseases. Existing literature published on the immunological crosstalk between the eye and the lung has been reviewed. The various roles of the ocular microbiome in lung health are also explored, examining the eye as a gateway for respiratory virus transmission, and assessing the impact of environmental irritants on both ocular and respiratory systems. This novel concept emphasizes a bidirectional relationship between respiratory and ocular health, suggesting that respiratory diseases may influence ocular conditions and vice versa, whereby this conception provides a comprehensive framework for understanding the intricate axis connecting both respiratory and ocular health. These aspects underscore the need for an integrative approach in the management of chronic respiratory diseases. Future research should further elucidate the in-depth molecular mechanisms affecting this axis which would pave the path for novel diagnostics and effective therapeutic strategies.

Assessment of Relation between Periodontal Disease and Macular Degeneration

Background and Aim

Periodontal disease may result in chronic inflammation and bacteremia in some people. The study aimed to evaluate the connection between periodontal disease and macular degeneration.

Materials and Methods

The specialist dental surgeon conducted the dental examination using a community periodontal index probe. An ophthalmologist performed the eye examination. Age-related macular degeneration (AMD) was identified through specific criteria such as the existence of particular types of drusen and pigmentary abnormalities.

Results

Two hundred participants were part of the study. According to the data, factors such as advanced age, limited education, low income, hypertension, cardiovascular disease (CVD), and hepatitis B surface antigen (HBsAg) presence were strongly linked to AMD in all participants.

Conclusion

Multiple studies have indicated a connection between periodontitis in the mouth and macular degeneration in individuals under 60 years of age.

Dry Eye Disease: An Update on Changing Perspectives on Causes, Diagnosis, and Management

Dry eye disease is a common clinical problem encountered by ophthalmologists worldwide. Interest in this entity has increased in recent years due to the consequences it has on the ocular surface after any surface procedure. With changing times, several new factors have come to light that can influence this disease. The effect of the COVID-19 pandemic has also been greatly felt, with a range of causes, starting from increased screen work to inflammatory processes, exacerbating the condition in many. With changes in the concepts of the etiopathogenesis of the disease, a paradigm shift has taken place in the approaches to treatment. More researchers are in favor of a new tear film-oriented approach that tries to localize the disease to a single component in the tear film. Innovation of newer techniques for the treatment of meibomian gland disease has also made its foray into clinical ophthalmology. Newer drug formulations and molecules are underway to better treat the inflammatory component of the disease. Many other receptors and targets for the treatment of dry eyes are being researched. This review hopes to provide a succinct, narrative summary of the relevant research on dry eye disease to date to increase awareness about the nature and future course of this disease and its management.

Differential Impact of 0.01% and 0.05% Atropine Eyedrops on Ocular Surface in Young Adults

Purpose

To evaluate the effect of low-concentration (0.01% and 0.05%) atropine eyedrops on ocular surface characteristics in young adults.

Methods

Twenty-six myopic students aged 18 to 30 years were randomly assigned to receive either 0.01% or 0.05% atropine once nightly for 14 days, followed by cessation, with a ≥14-day interval between each administration. Assessments were conducted one, two, seven, and 14 days after using atropine with corresponding timepoints after atropine cessation. Tear meniscus height and first and average noninvasive keratograph tear film breakup time (NIKBUT-first, NIKBUT-average) were measured using Keratograph 5M, whereas the objective scatter index (OSI) was measured by OQAS II devices; the ocular surface disease index (OSDI) score was also obtained.

Results

The mean OSI peaked after two days of administration of 0.05% atropine (β = 0.51, P = 0.001), accompanied by significant decreases in NIKBUT-first (β = -7.73, P < 0.001) and NIKBUT-average (β = -8.10, P < 0.001); the OSDI peaked after 14 days (β = 15.41, P < 0.001). The above parameters returned to baseline one week after atropine discontinuation (all P > 0.05). NIKBUT-first and NIKBUT-average reached their lowest points after 14 days of 0.01% atropine administration (NIKBUT-first: β = -4.46, P = 0.005; NIKBUT-average: β = -4.42, P = 0.001), but those significant changes were diminished once atropine treatment stopped.

Conclusions

Young adult myopes experienced a significant but temporary impact on the ocular surface with 0.05% atropine administration, whereas 0.01% atropine had a minimal effect.

Translational Relevance

The investigation of the ocular surface effects of different concentrations of atropine may inform evidence-based clinical decisions regarding myopia control in young adults.

Mechanisms of PM10 Disruption of the Nrf2 Pathway in Cornea

We have previously shown that PM10 exposure causes oxidative stress and reduces Nrf2 protein levels, and SKQ1 pre-treatment protects against this damage in human corneal epithelial cells (HCE-2). The current study focuses on uncovering the mechanisms underlying acute PM10 toxicity and SKQ1-mediated protection. HCE-2 were pre-treated with SKQ1 and then exposed to 100 μg/mL PM10. Cell viability, oxidative stress markers, programmed cell death, DNA damage, senescence markers, and pro-inflammatory cytokines were analyzed. Nrf2 cellular location and its transcriptional activity were determined. Effects of the Nrf2 inhibitor ML385 were similarly evaluated. Data showed that PM10 decreased cell viability, Nrf2 transcriptional activity, and mRNA levels of antioxidant enzymes, but increased p-PI3K, p-NFκB, COX-2, and iNOS proteins levels. Additionally, PM10 exposure significantly increased DNA damage, phosphor-p53, p16 and p21 protein levels, and β-galactosidase (β-gal) staining, which confirmed the senescence. SKQ1 pre-treatment reversed these effects. ML385 lowered the Nrf2 protein levels and mRNA levels of its downstream targets. ML385 also abrogated the protective effects of SKQ1 against PM10 toxicity by preventing the restoration of cell viability and reduced oxidative stress. In conclusion, PM10 induces inflammation, reduces Nrf2 transcriptional activity, and causes DNA damage, leading to a senescence-like phenotype, which is prevented by SKQ1.

Consequences of exposure to particulate matter on the ocular surface: Mechanistic insights from cellular mechanisms to epidemiological findings

Exposure to air pollutants, especially in the case of particulate matter (PM), poses significant health risks throughout the body. The ocular surface is directly exposed to atmospheric PM making it challenging to avoid. This constant exposure makes the ocular surface a valuable model for investigating the impact of air pollutants on the eyes. This comprehensive review assembles evidence from across the spectrum, from in vitro and in vivo investigations to clinical studies and epidemiological studies, offering a thorough understanding of how PM10 and PM2.5 affect the health of the ocular surface. PM has been primarily found to induce inflammatory responses, allergic reactions, oxidative stress, DNA damage, mitochondrial impairment, and inhibit the proliferation and migration of ocular surface cells. In toto these effects ultimately lead to impaired wound healing and ocular surface damage. In addition, PM can alter tear composition. These events contribute to ocular diseases such as dry eye disease, blepharitis, conjunctivitis, keratitis, limbal stem cell deficiency and pterygium. Importantly, preexisting ocular conditions such as dry eye, allergic conjunctivitis, and infectious keratitis can be worsened by PM exposure. Adaptive responses may partially alleviate the mentioned insults, resulting in morphological and physiological changes that could be different between periods of short-term and long-term exposure. Particle size is not the only determinant of the ocular effect of PM, the composition and solubility of PM also play critical roles. Increasing awareness of how PM affects the ocular surface is crucial in the field of public health, and mechanistic insights of these adverse effects may provide guidelines for preventive and therapeutic strategies in dealing with a polluted environment.

Cleaning effects of eyewashes on ocular surface symptoms caused by air pollution in a single-center, two-arm, nonrandomized trial in Indonesia: first report from Jakarta study

PURPOSE

Air pollutants, such as Asian sand and particulate matter (PM) 2.5, have become a global concern for causing ocular inflammation and allergic symptoms. This study, as part of an international investigation, examined the effects of eyewashes for ocular damage caused by air pollution in Indonesia.

METHODS

This was a single-center, patient- and-evaluator-blinded, parallel two-arm, nonrandomized trial. In Jakarta, Indonesia, 30 eyes of 15 car commuters and 30 eyes of 15 motorcycle commuters were recruited from healthy volunteers. After commuting to work, both eyes were washed with a commercial eyewash. Before and after eyewashing, eight items of ocular surface symptoms and four items of rhinitis subjective symptoms were scored using a modified Japanese Allergic Conjunctival Disease Quality-of-Life Questionnaire.

RESULTS

Five of the 12 subjective symptom scores before eyewashing were higher in motorcycle commuters than in car commuters (p < 0.05). Motorcycle commuters showed improvement in the five symptom scores of "itchy eyes, foreign body sensation, eye mucus, dryness, and eye strain" after eyewashing compared to before eyewashing (p < 0.05). In all patients, sootlike particles and ocular mucus were found in the solutions collected after eyewashing.

CONCLUSION

These findings indicate that eyewashing for ocular symptoms caused by airborne particles may be effective in removing foreign particles from the ocular surface and relieving subjective symptoms.

A Comprehensive Analysis of the Influence of Temperature and Humidity on Dry Eye Disease

PURPOSE

To investigate the effects of humidity and temperature on dry eye disease (DED).

METHODS

A retrospective, clinic-based study was conducted on DED patients undergoing dry eye treatment. Patients were followed up at least twice, and symptoms and signs were evaluated using the Symptoms Assessment Questionnaire in Dry Eye (SANDE) score, tear secretion, tear film breakup time (TBUT), ocular staining score, and tear osmolarity. Mean humidity and temperature values for 1 week before ocular examinations were used as the environmental exposure level. The relationship between humidity and temperature, with DED clinical parameters was analyzed in single- and multi-environmental factor models.

RESULTS

The study included 33 patients with a mean age of 53.9 ± 12.2 years. The low humidity group showed significantly higher SANDE scores (p = 0.023) and tear osmolarity (p = 0.008), and the low temperature group had higher SANDE scores (p = 0.004), ocular staining scores (p = 0.036), and tear osmolarity (p < 0.001). In the linear mixed model, single factor analysis showed that an increase in humidity resulted in decreased SANDE scores (p = 0.043), and an increase in temperature led to a decrease in SANDE score (p = 0.007), ocular staining score (p = 0.007), and tear osmolarity (p = 0.012). In the multifactor analysis, changes in humidity had no significant effect on dry eye parameters, but an increase in temperature was significantly correlated with decreased SANDE score (p = 0.026), ocular staining score (p = 0.024), and tear osmolarity (p = 0.002).

CONCLUSIONS

Lower temperature led to aggravated symptoms and signs of DED and the effect of temperature on DED was more pronounced than humidity. Tear osmolarity was the most sensitive clinical parameter to be affected by climate factors in DED patients.

Potential benefits of Malva sylvestris in dry-eye disease pathology in vitro based on antioxidant, wound-healing and anti-inflammatory properties

Dry eye disease (DED) is a common chronic ocular surface disease. Available therapies are effective but often associated with side effects. This study investigates the potential of a Malva sylvestris L. flower extract and two defined preparations, a mucilage and a polyphenol rich fraction, on cells that are essential for the DED pathology. Furthermore, single compounds were isolated and characterised out of the polyphenol fraction. The M. sylvestris extract and its two fractions reduced reactive oxygen species (ROS) in an ultraviolet-induced model and promoted wound healing capacity of HCE-T cells, but only the polyphenol fraction and the flower extract exhibited significant radical scavenging activity. The flower extract and the polyphenol fraction inhibited cytokine secretion (IL-6, TNF-α, IL-8) from HCE-T cells and THP-1 cells. In contrast, the mucilage fraction led to an increase in mediator secretion. The NF-κB activity and calcium influx in THP-1 and Jurkat cells, respectively was decreased by treatment with the flower extract and the polyphenol fraction, whereas the mucilage fraction had no influence on these parameters. Moreover, the flower extract and the mucilage fraction at low concentration could stimulate meibomian gland cells' lipid accumulation. The isolated single compounds showed no effect on analysed parameters, except a coumarin derivative and malvin which showed ROS inhibition effects.

Evaluation of the Tear Meniscus Using Optical Coherence Tomography in Meibomian Gland Dysfunction

INTRODUCTION

This study aimed to evaluate tear meniscus parameters in meibomian gland dysfunction (MGD) using optical coherence tomography and ImageJ software.

METHODS

We enrolled 66 eyes of 66 participants and measured tear meniscus parameters, including height, depth, turbidity, and percentage area occupied by particles (PAOP) in the meniscus in the MGD and control groups.

RESULTS

Tear meniscus turbidity and PAOP were significantly higher in the MGD group, but tear meniscus height (TMH) and depth (TMD) did not differ significantly between groups. Tear meniscus turbidity and PAOP were positively correlated with each other and ocular surface parameters, including OSDI and ocular surface staining scores.

CONCLUSION

Tear meniscus turbidity and PAOP were higher in the MGD group than in the control group; therefore, they can be used as significant non-invasive parameters in the prediction of MGD. TMH and TMD did not differ significantly between groups.

Short-term effect of meteorological factors and extreme weather events on daily outpatient visits for dry eye disease between 2013 and 2020: a time-series study in Urumqi, China

Dry eye disease (DED) is a common disorder of tear secretion on the ocular surface caused by multiple factors with dry eyes as the main symptom, but until now studies focusing on relationship between local meteorological factors and ocular surface diseases in Urumqi are very limited. Besides, the effects of long-term and extreme meteorological factors on DED and the lag effect have not been fully evaluated. Electronic case information of 9970 DED outpatients from the Ophthalmology Department of the First Affiliated Hospital of Xinjiang Medical University (Urumqi, Xinjiang, China) between January 1, 2013, and December 31, 2020, was screened and analyzed. We used a time-series analysis design and a quasi-Poisson generalized linear regression model combined with a distributed lagged nonlinear model (DLNM) to fit the effects of exposure to different meteorological factors and extreme weather on DED outpatient visits. Subgroup analyses were further performed for gender, age, and season. The results showed that exposure to extremely low mean temperature (P1:RR = 1.18), atmospheric pressure (P1:RR = 1.11), and extremely high relative humidity (P99:RR = 1.35) were the risk factors, while extremely high atmospheric pressure (P90:RR = 0.883) and extremely low humidity (P10:RR = 0.856) appeared to have a positive effect on reduced risk of DED. Relative humidity exhibited a 1-day lag effect (RR = 1.06). Increased mean temperature positively affected female DED patients (RR = 0.761) with similar effects in the cold season (RR = 0.926). However, elevated relative humidity had a negative effect on female patients (RR = 1.14). We conducted the first large sample size time-series analysis study in this major city at the farthest distance from the ocean in the world and in northwest China, confirming the association of DED outpatient visits with the remaining three meteorological factors except wind speed in Urumqi, and a larger sample size multi-center epidemiological study with a longer duration is still needed.

The environment and dry eye-manifestations, mechanisms, and more

Dry eye disease (DED) is a multifactorial condition that often presents with chronic symptoms of pain (that can be characterized as "dryness," "burning," and "irritation," to name a few) and/or fluctuating or poor-quality vision. Given its multifactorial nature, several pathophysiologic mechanisms have been identified that can underlie symptoms, including tear film, ocular surface, and/or corneal somatosensory nerve abnormalities. Research has focused on understanding how environmental exposures can increase the risk for DED flares and negatively impact the tear film, the ocular surface, and/or nerve health. Given that DED is a common condition that negatively impacts physical and mental functioning, managing DED requires multiple strategies. These can include both medical approaches and modulating adverse environmental conditions, the latter of which may be a cost-effective way to avoid DED flares. Thus, an understanding of how environmental exposures relate to disease is important. This Review summarizes research on the relationships between environmental exposures and DED, in the hope that this information will engage healthcare professionals and patients to consider environmental manipulations in their management of DED.

Emerging roles of air pollution and meteorological factors in autoimmune eye diseases

Autoimmune eye diseases (AEDs), a collection of autoimmune inflammatory ocular conditions resulting from the dysregulation of immune system at the ocular level, can target both intraocular and periorbital structures leading to severe visual deficit and blindness globally. The roles of air pollution and meteorological factors in the initiation and progression of AEDs have been increasingly attractive, among which the systemic and local mechanisms are both involved in. Exposure to excessive air pollution and extreme meteorological conditions including PM2.5/PM0.1, environmental tobacco smoke, insufficient sunshine, and high temperature, etc., can disturb Th17/Treg balance, regulate macrophage polarization, activate neutrophils, induce systemic inflammation and oxidative stress, decrease retinal blood flow, promote tissue fibrosis, activate sympathetic nervous system, adversely affect nutrients synthetization, as well as induce heat stress, therefore may together deteriorate AEDs. The crosstalk among inflammation, oxidative stress and dysregulated immune system appeared to be prominent. In the present review, we will concern and summarize the potential mechanisms underlying linkages of air pollution and meteorological factors to ocular autoimmune and inflammatory responses. Moreover, we concentrate on the specific roles of air pollutants and meteorological factors in several major AEDs including uveitis, Graves' ophthalmopathy (GO), ocular allergic disease (OAD), glaucoma, diabetic retinopathy (DR), etc.

TFOS Lifestyle Report: Impact of environmental conditions on the ocular surface

Environmental risk factors that have an impact on the ocular surface were reviewed and associations with age and sex, race/ethnicity, geographical area, seasonality, prevalence and possible interactions between risk factors are reviewed. Environmental factors can be (a) climate-related: temperature, humidity, wind speed, altitude, dew point, ultraviolet light, and allergen or (b) outdoor and indoor pollution: gases, particulate matter, and other sources of airborne pollutants. Temperature affects ocular surface homeostasis directly and indirectly, precipitating ocular surface diseases and/or symptoms, including trachoma. Humidity is negatively associated with dry eye disease. There is little data on wind speed and dewpoint. High altitude and ultraviolet light exposure are associated with pterygium, ocular surface degenerations and neoplastic disease. Pollution is associated with dry eye disease and conjunctivitis. Primary Sjögren syndrome is associated with exposure to chemical solvents. Living within a potential zone of active volcanic eruption is associated with eye irritation. Indoor pollution, "sick" building or house can also be associated with eye irritation. Most ocular surface conditions are multifactorial, and several environmental factors may contribute to specific diseases. A systematic review was conducted to answer the following research question: "What are the associations between outdoor environment pollution and signs or symptoms of dry eye disease in humans?" Dry eye disease is associated with air pollution (from NO2) and soil pollution (from chromium), but not from air pollution from CO or PM10. Future research should adequately account for confounders, follow up over time, and report results separately for ocular surface findings, including signs and symptoms.

Current social determinants of health and social risk factors in conditions of the cornea: a scoping review

PURPOSE OF REVIEW

To achieve health equity in eye health and vision care, social determinants of health (SDoH) and the associated social risk factors must be addressed. To address SDoH and social risk factors in ophthalmology, they must first be identified. The purpose of this review was to determine the SDoH and social risk factors in conditions of the cornea that have most recently been explored.

RECENT FINDINGS

This review identified social risk factors associated with all five domains of SDoH, as outlined by Healthy People 2030. The neighborhood and built environment was the domain identified the most for both exploration and observation. The social and community context domain was the least explored, and healthcare access and quality and social and community context domains were the least observed. The cornea condition explored the most in relation to SDoH was dry eye syndrome.

SUMMARY

The findings from this review can inform clinicians on the social risk factors that could be screened for in eye care facilities, so patients can be connected with services to minimize the impact of social risk factors on cornea conditions. Furthermore, the findings have identified cornea conditions and domains of SDoH that are understudied which can be an area for future studies by vision researchers.

The effect of social determinants of health on severity of microbial keratitis presentation at a tertiary eye care hospital in Southern India

Purpose

Understanding the association between social determinants of health (SDoHs) and microbial keratitis (MK) can inform underlying risk for patients and identify risk factors associated with worse disease, such as presenting visual acuity (VA) and time to initial presentation.

Methods

This was a cross-sectional study was conducted with patients presenting with MK to the cornea clinic at a tertiary care hospital in Madurai, India. Patient demographics, SDoH survey responses, geographic pollution, and clinical features at presentation were collected. Descriptive statistics, univariate analysis, multi-variable linear regression models, and Poisson regression models were utilized.

Results

There were 51 patients evaluated. The mean age was 51.2 years (SD = 13.3); 33.3% were female and 55% did not visit a vision center (VC) prior to presenting to the clinic. The median presenting logarithm of the minimum angle of resolution (logMAR) VA was 1.1 [Snellen 20/240, inter-quartile range (IQR) = 20/80 to 20/4000]. The median time to presentation was 7 days (IQR = 4.5 to 10). The average particulate matter 2.5 (PM2.5) concentration, a measure of air pollution, for the districts from which the patients traveled was 24.3 μg/m3 (SD = 1.6). Age- and sex-adjusted linear regression and Poisson regression results showed that higher levels of PM2.5 were associated with 0.28 worse presenting logMAR VA (Snellen 2.8 lines, P = 0.002). Patients who did not visit a VC had a 100% longer time to presentation compared to those who did (incidence rate ratio = 2.0, 95% confidence interval = 1.3-3.0, P = 0.001).

Conclusion

Patient SDoH and environmental exposures can impact MK presentation. Understanding SDoH is important for public health and policy implications to mitigate eye health disparities in India.

In-Situ Thermoresponsive Hydrogel Containing Resveratrol-Loaded Nanoparticles as a Localized Drug Delivery Platform for Dry Eye Disease

Dry eye disease (DED) is a dynamic and complex disease that can cause significant damage to the ocular surface and discomfort, compromising the patient's quality of life. Phytochemicals such as resveratrol have received increasing attention due to their ability to interfere with multiple pathways related to these diseases. However, the low bioavailability and the poor therapeutic response of resveratrol hinder its clinical applications. Cationic polymeric nanoparticles, in combination with in situ gelling polymers, could represent a promising strategy to prolong drug corneal residence time reducing the frequency of administration and increasing the therapeutic response. Eyedrop formulations, based on acetylated polyethyleneimine-modified polylactic-co-glicolyc acid- (PLGA-PEI) nanoparticles loaded with resveratrol (RSV-NPs) were dispersed into poloxamer 407 hydrogel and characterized in terms of pH, gelation time, rheological properties, in vitro drugs release, and biocompatibility. Moreover, the antioxidant and anti-inflammatory effects of RSV were assessed in vitro by mimicking a DED condition through the exposition of epithelial corneal cells to a hyperosmotic state. This formulation exhibited sustained release of RSV for up to 3 days, exerting potent antioxidant and anti-inflammatory effects on corneal epithelial cells. In addition, RSV reversed the mitochondrial dysfunction mediated by high osmotic pressure, leading to upregulated sirtuin-1 (SIRT1) expression, an essential regulator of mitochondrial function. These results suggest the potential of eyedrop formulation as a platform to overcome the rapid clearance of current solutions for treating various inflammation- and oxidative stress-related diseases such as DED.

The Autoimmune Rheumatic Disease Related Dry Eye and Its Association with Retinopathy

Dry eye disease is a chronic disease of the ocular surface characterized by abnormal tear film composition, tear film instability, and ocular surface inflammation, affecting 5% to 50% of the population worldwide. Autoimmune rheumatic diseases (ARDs) are systemic disorders with multi-organ involvement, including the eye, and play a significant role in dry eye. To date, most studies have focused on Sjögren's syndrome (one of the ARDs) since it manifests as two of the most common symptoms-dry eyes and a dry mouth-and attracts physicians to explore the relationship between dry eye and ARDs. Many patients complained of dry eye related symptoms before they were diagnosed with ARDs, and ocular surface malaise is a sensitive indicator of the severity of ARDs. In addition, ARD related dry eye is also associated with some retinal diseases directly or indirectly, which are described in this review. This review also summarizes the incidence, epidemiological characteristics, pathogenesis, and accompanying ocular lesions of ARD's related dry eye, emphasizing the potential role of dry eye in recognition and monitoring among ARDs patients.

Long-term effects of meteorological factors and extreme weather on daily outpatient visits for conjunctivitis from 2013 to 2020: a time-series study in Urumqi, China

Conjunctivitis is a common multifactorial inflammatory ocular surface disease characterized by symptoms such as congestion, edema, and increased secretion of conjunctival tissue, and the potential effects of meteorological factors as well as extreme meteorological factors on conjunctivitis and their lagging effects have not been fully evaluated. We obtained the electronic case information of 59,731 outpatients with conjunctivitis from the Ophthalmology Department of the First Affiliated Hospital of Xinjiang Medical University (Urumqi, Xinjiang, China) for the period from January 1, 2013, to December 31, 2020. Meteorological data for daily mean temperature (°C), daily relative humidity (%), daily average wind speed (m/s), and atmospheric pressure (hPa) were obtained from the China Meteorological Data Sharing Service. The air pollutant data were obtained from 11 standard urban background fixed air quality monitors. A time-series analysis design and a quasi-Poisson generalized linear regression model combined with a distributed lagged nonlinear model (DLNM) were used to fit the effects of exposure to different meteorological factors and extreme weather on conjunctivitis outpatient visits. Subgroup analyses were performed on gender, age and season, and type of conjunctivitis. Univariate and multifactorial model results indicated that each 10-unit increase in mean temperature and relative humidity was associated with an increased risk of conjunctivitis outpatient visits, while each 10-unit increase in atmospheric pressure was associated with a decreased risk. The results of the extreme weather analysis suggested that extremely low levels of atmospheric pressure and relative humidity as well as extreme levels of temperature were associated with an increased risk of outpatient conjunctivitis visits, and extreme wind speeds were associated with a decreased risk. The results of the subgroup analysis suggested gender, age, and seasonal differences. We conducted the first large sample size time-series analysis in the large city furthest from the ocean in the world and confirmed for the first time that elevated mean temperature and extreme low levels of relative humidity in Urumqi were risk factors for local conjunctivitis outpatient visits, while elevated atmospheric pressure and extreme low levels of wind speed were protective factors, and there were lagged effects of temperature and atmospheric pressure. Multicenter studies with larger sample sizes are needed.

Correlation Between Air Quality Index and Tear Film Lipid Layer Thickness: Comparison Between Patients with Sjogren's Syndrome and with Meibomian Gland Dysfunction

Purpose: To evaluate the effect of air pollution on the tear film stability by analyzing the correlation between Air Quality Index (AQI) and Lipid Layer thickness (LLT) in Xuzhou.Methods: As a prospective descriptive observational study, 284 patients with meibomian gland dysfunction (MGD), 157 patients with Sjögren's syndrome (SS), and 264 healthy volunteers were included. The tear film lipid layer thickness of the three groups of subjects was measured weekly and compared with the air quality index to analyze the correlation between the two indicators. Logistic regression analysis and linear regression analysis were used to analyze the effect of AQI on the thickness of the tear film lipid layer. The change of LLT with air pollution at different AQI levels was also analyzed.Results: There are obvious seasonal differences in the changes of air pollution index in Xuzhou. Significant differences could be observed in the thickness of the lipid layer of the tear film among the three groups. LLT in the MGD group and SS group decreased with the aggravation of air pollution, while remained unchanged in the control group. There was strong evidence of correlation between LLT of the MGD group (F = 353.494, p < 0.01, adjusted R2 = 0.695) and the SS group (F = 502.404, p < 0.01, adjusted R2 = 0.764) with AQI, while there was minor correlation between LLT with AQI in control group (F = 8.525, p < 0.01, adjusted R2 = 0.046).Conclusions: Air pollution can cause a decrease in the thickness of the tear film lipid layer, thereby affecting tear film stability, leading to the occurrence of dry eye.

Vanadium inhalation effects on the corneal ciliary neurotrophic factor (CNTF): study in a murine model

PURPOSE

Air pollution is a public health problem caused by predatory human activities and the indiscriminate burning of fossil fuels that liberate particulate matter (PM) into the atmosphere. Vanadium (V) adheres to them and reaches the bloodstream and different organs such as the eye when inhaled. Another way to reach the eye is by direct contact, and the cornea is the first layer exposed. Ciliary neurotrophic factor (CNTF) is secreted by the corneal nerves and some of its functions include self-renewal maintenance and wound healing by the activation of STAT3. Previous reports from our group indicate the activation of STAT3 after the inhalation of V, adhered to PM.

OBJECTIVE

To analyse the effect of V inhalation in the expression of CNTF. Method: CD-1 male mice were exposed for 4 and 8 weeks to V inhalation. The eyes were removed, and the corneas were processed for immunohistochemistry for CNTF and analysed by densitometry. The same slides were used to evaluate histological modifications and to measure the corneas' anterior epithelial and endothelial thickness.

RESULTS

A decrease in CNTF expression in the anterior epithelium in the 8th week, as well as an increase in the endothelial and corneal thickness and disarray of all the layers of the anterior epithelium.

CONCLUSION

V inhalation disturbs the architecture of the cornea and modifies the presence of CNTF which might modify the renewal of the corneas after exposure to PM air pollution.

Indoor air pollution and human ocular diseases: Associated contaminants and underlying pathological mechanisms

People spend a long time indoors, especially young children. The risk of indoor pollution on human health is one of the current hotspots in environmental and public health. The human ocular surface is highly susceptible to indoor environment quality. Epidemiological data have linked human ophthalmological disorders with exposure to indoor pollution. In this review, we summarized the adverse impacts of indoor pollution on the human ocular surface. Several studies demonstrated that indoor contaminants including particulate matter, volatile/semi-volatile organic compounds, heavy metals, and fuel combustion and cigarette smoke exposure were associated with the incidence of human dry eye, conjunctivitis, glaucoma, cataracts, age-related macular degeneration, and keratitis. In addition, toxicological investigations revealed that indoor pollution-induced induced chronic inflammation, oxidative damage, and disruption of tight junctions are the main underlying pathological mechanisms for ocular surface diseases. Taken together, this review may expand the understanding of pollution-induced eye disorder and highlight the importance of reducing associated contaminants to decrease their detrimental effects on human eyes.

Ocular manifestations of psoriasis: An inflammatory disease beyond the skin

Background

Psoriasis is a chronic inflammatory disorder, mainly involves skin.

Aims

To evaluate the prevalence of ocular manifestations in Iranian patients with psoriasis, compared to healthy controls.

Materials and methods

Forty psoriasis patients and 40 age- and gender-matched healthy controls were enrolled in the study and underwent a comprehensive ophthalmologic assessment.

Results

Only meibomian gland dysfunction was significantly more common among patients with psoriasis, compared to control group (p value: 0.011). Regarding intraocular pressure (IOP), the mean values for both patients and healthy controls were within the normal range and mean IOP in patients was even lower than normal controls, although this difference was significant only for left eye (p value: 0.049). A strong positive correlation between PASI and tear meniscus height for both right and left eyes (p value: 0.005, r: 0.44 for OD and p value: 0.003, r: 0.46 for OS.) was noted. Meibomian gland dysfunction was also positively correlated with disease duration for right and left palpebras (p: 0.04, r: 0.31 for both).

Conclusion

Psoriasis can lead to meibomian gland dysfunction, especially in patients with long-lasting disease. Hence, dermatologists and general practitioners should be vigilant in this regard when visiting psoriasis patients, especially those who have higher PASI values or long-lasting disease.

The impact of the first United Kingdom COVID-19 lockdown on environmental air pollution, digital display device use and ocular surface disease symptomatology amongst shielding patients

Worldwide lockdown reduced air pollution during the first phase of the COVID-19 pandemic. The relationship between exposure to ambient air pollution, digital display device use and dry eye symptoms amongst patients with severe ocular surface disease (OSD) were considered. Symptoms and air pollutant concentrations for three different time periods (pre, during and post COVID-19 lockdown) were analysed in 35 OSD patients who achieved an immunosuppression risk-stratification score > 3 fulfilling the UK Government criteria for 12-week shielding. OSDI symptoms questionnaire, residential postcode air pollution data obtained from the Defra Automated Urban and Rural monitoring network for concentrations of nitrogen dioxide (NO₂), nitrogen oxides (NOx), particulate matter (PM) with diameters below 10 µm and 2.5 µm, and English Indices of Deprivation were analysed. Significant reductions in NO₂ and NOx concentrations were observed between pre- and during-lockdown periods, followed by a reversal in the post-lockdown period. Changes were linked to the Living Environment outdoor decile. A 12% increase (p = 0.381) in symptomatology during-lockdown was observed that reversed post-lockdown by 19% (p = 0.144). OSDI scores were significantly correlated with hours spent on digital devices (r² = 0.243) but not with air pollutant concentrations. Lockdown measures reduced ambient air pollutants whilst OSD symptomatology persisted. Environmental factors such as increased time indoors and use of bluescreen digital devices may have partly played a role.

Moxibustion with Walnut Shell Spectacles Could Improve the Objective Symptoms and Tear Film Stability of Patients with Dry Eye Disease: A Randomized Controlled Trial

Objectives

This study aims to evaluate the efficacy and acceptability of moxibustion with walnut shell spectacles in treating dry eye disease (DED) patients and to provide treatment options.

Methods

126 DED patients were randomly allocated into the moxibustion group (treated by moxibustion with walnut shell spectacles, 64 cases) and the artificial tears group (treated with sodium hyaluronate eye drops, 62 cases). Evaluate the changes in the ocular surface disease index (OSDI), the visual analogue scale (VAS) of ocular discomfort, the tear film break-up time (TBUT), corneal fluorescein staining (CFS), and the Schirmer I test during the trial at baseline and after 1-week, 2-week, 3-week, and 4-week treatment. Evaluate the OSDI scale and the ocular symptom VAS scale one month after the end of treatment.

Results

There were no significant differences in baseline characteristics between the two groups. For OSDI scores, the results showed that the efficacy of the moxibustion group was no less than that of the artificial tear group. For VAS of ocular discomfort, both groups significantly reduced their score compared with baseline, and for the moxibustion group, the decrease was more significant. For TBUT, FAS, and PPS, results showed that the efficacy of the moxibustion group was significant in both eyes after 4 weeks of treatment, but the right eye was in the artificial tear group. For CFS and Schirmer I test scores, there was no significant effect for both groups.

Conclusion

Moxibustion with walnut shell spectacles could improve the clinical symptoms and tear film stability of DED patients; however, it has no significant efficacy on improving corneal injury and tear secretion, just the same as sodium hyaluronate eye drops. Nevertheless, moxibustion with walnut shell spectacles may have better effects on the self-assessment of ocular discomfort than sodium hyaluronate eye drops.

Clinical association between trace elements of tear and dry eye metrics

Trace elements exposure is proposed to play a role in the pathogenesis of the systemic disease. Emerging studies have suggested that trace metal exposure may contribute to dry eye disease. Our study primarily aimed to investigate the association between trace metal exposure in tear samples and the presence of dry eye metrics in the shipyard industry. Overall, 84 eligible participants from the shipyard industry were included in this cross-sectional study. The parameters for identifying dry eye symptoms included O.S.D.I., SPEED, N.I.B.U.T., and ocular surface conditions, such as tear meniscus height, eye blinking, and meibomian gland area were performed by S.B.M. sistemi ocular surface analyzer. The concentration of tear trace elements was detected by inductively coupled plasma mass spectroscopy (ICP-MS). The association between tear trace elements and dry eye parameters was investigated using regression models. Participants in the exposure group had significantly higher levels of tear Pb than the control group. In the exposure group, tear Pb was significantly associated with increased SPEED and O.S.D.I. score with beta coefficients of 0.144 (95% CI 0.092, 0.197), 0.121 (95% CI 0.049, 0.194), respectively, and decreased lower and upper meibomian gland area with beta coefficients of - 0.158 (- 0.283, - 0.033) and - 0.228 (- 0.396, - 0.061), respectively. Tear trace elements exposure is considered to impact the appearance of dry eye metrics. Improving the occupational environment and monitoring the ocular surface health may benefit workers under exposure to trace elements.

Ambient gaseous pollutant exposure and incidence of visual impairment among children and adolescents: findings from a longitudinal, two-center cohort study in China

Evidence on the effects of exposure to ambient gaseous pollutants on children's vision was consistently scarce. We aimed to explore the effect of ambient gaseous pollutant exposure on the incidence of visual impairment (VI) in children. From 2005 to 2018, a total of 340,313 children without VI participated in a longitudinal and two-center dynamic cohort. The logMAR acuity was used to assess visual function. The space-time extremely randomized trees model was used to estimate SO₂ and CO exposures levels. The association between SO₂ and CO and VI risks among children was assessed using a proportional hazards model with a restricted cubic spline. Subgroup analyses stratified by gender and grades were used to investigate the differences in an association of SO₂ and CO exposures with childhood VI. A total of 158381 (46.54%) children experienced an new incident VI. A ten-unit (10 μg/m³) increase in SO₂ exposure concentrations was significantly associated with a 1.70 times higher risk of childhood VI. In addition, a 0.1-unit (0.1 mg/m³) increase in CO exposure was significantly associated with a 1.22 times higher risk of childhood VI. The positive association between ambient gaseous pollutants (including SO₂ and CO exposures) and childhood VI risks remained even after adjusting for other environmental variables. An increase in the incidence of VI in children was positively linked to SO₂ and CO exposure. Such evidence might aid governments in developing strategies to interfere with children's eyesight by decreasing air pollution and changing school curricula.

Lifitegrast Ophthalmic Solution 5% Is a Safe and Efficient Eyedrop for Dry Eye Disease: A Systematic Review and Meta-Analysis

Dry eye disease (DED) is a multifactorial disease that causes ocular discomfort and visual impairment on a damaged ocular surface. Lifitegrast, a novel T-cell integrin antagonist, was approved in the United States in July 2016 as a 5% (50 mg/mL) ophthalmic solution for DED management. Currently, no meta-analysis and systemic review based on relevant studies have been conducted. This study aimed to evaluate the efficacy and safety of lifitegrast in patients with DED. We systematically searched Embase, Medline, PubMed, and Web of Science for randomized controlled trials (RCTs) and nonrandomized studies evaluating lifitegrast effects on symptomatic DED. Then, inferior corneal staining score, total corneal staining score (TCSS), nasal lissamine staining score (NLSS), total lissamine staining score, ocular discomfort score (ODS), eye discomfort score (visual analog scale (VAS) score), eye dryness score (EDS), ocular surface disease index score (OSDI-S), and tear break-up time (TBUT) were assessed. Clinical global impression and safety profiles were also evaluated. The studies were pooled in a random-effects model. We included five RCTs, one case-control study, and four longitudinal or retrospective studies, comprising 3197 participants. In the meta-analysis, lifitegrast was superior to the placebo because it improved TCSS, NLSS, TBUT, ODS, eye discomfort score, EDS, and OSDI-Sin DED. However, lifitegrast showed higher risks for ocular and non-ocular treatment-emergent adverse events (TEAEs) overall or at a mild or moderate level. Nonetheless, its incidence of adverse events slightly differed from that in the placebo, especially instillation site discomforts and dysgeusia, thereby considered safe and tolerable. Claims of withdrawal during follow-up caused by TEAEs were extremely rare. Lifitegrast improves DED, although dysgeusia, installation site pain, and irritation may be a concern for some. Overall, most of the adverse events are tolerable. Lifitegrast can alleviate refractory DED and improves patients' quality of life.

Dry eye syndrome: comprehensive etiologies and recent clinical trials

Dry eye syndrome (DES) is multifactorial and likely to be a cause of concern more so than ever given the rapid pace of modernization, which is directly associated with many of the extrinsic causative factors. Additionally, recent studies have also postulated novel etiologies that may provide the basis for alternative treatment methods clinically. Such insights are especially important given that current approaches to tackle DES remains suboptimal. This review will primarily cover a comprehensive list of causes that lead to DES, summarize all the upcoming and ongoing clinical trials that focuses on treating this disease as well as discuss future potential treatments that can improve inclusivity.

Autophagy Protects Ocular Surface Against Overactivated Inflammation by Degrading Retinoic Acid-Induced Gene-I in Human Conjunctival Epithelial Cells

Purpose: To evaluate the pathological role of autophagy in dry eye diseases by detecting the autophagic degradation of RIG-I, a master RNA-sensing receptor in cells. Methods: RNA-sequencing analysis and qPCR analysis of the expression level of genes related to IFN-I signaling pathway was used to evaluate the inflammatory level of cells overexpressed with RIG-I or empty vector, which was further confirmed by WB analysis. Chemical treatment (3-methyladenine, chloroquine, NH₄Cl, rapamycin, torin 1 or trehalose) or gene knockdown was used to modulate autophagy. When the autophagy level was regulated, the autophagic degradation of RIG-I and its pathological role in dry eye diseases were determined by detecting the protein level of RIG-I and the level of cell inflammation. Results: Cells that overexpressed RIG-I showed increased expression of genes involved in the IFN-I signaling pathway compared with cells transfected with an empty vector. Inhibition of autophagy leaded to the accumulation of RIG-I in HCECs, combined with the aggravation of the RIG-I-mediated IFN-I signaling pathway. Contrarily, promoting the autophagic degradation of RIG-I by trehalose treatment could alleviate IFN-I signaling pathway. Conclusions: Autophagy could protect the ocular surface against IFN-I signaling pathway by degrading RIG-I in HCECs. This process may restrict the overactivation of inflammation in the pathological development of dry eye disease.

Associations of Humidity and Temperature With Cataracts Among Older Adults in China

Background

The burden of cataracts was substantial in the current aging world. However, few epidemiological studies have examined the associations between climate and weather conditions and cataract in older populations. We aimed to investigate the associations of air relative humidity and temperature with cataracts in older adults in China.

Methods

We used the cohort data from 2002, 2005, 2008, 2011, 2014, and 2018 waves of the Chinese Longitudinal Healthy Longevity Survey (CLHLS). A total of 62,595 Chinese older adults aged between 65 and 105 years were included in the analyses. City-level annual average air humidity and temperature during 2001 and 2017 (before the survey year) was used to measure population exposure. A cataract was self-reports based on the medical record or the doctor's diagnosis and 8,071 older adults had cataract. Covariates included socio-demographic, health status, lifestyles, and chronic conditions. We adopted the Generalized estimation equation (GEE) model to analyze the associations of relative humidity and temperature with cataracts.

Results

We found that the average relative humidity (OR: 0.99; 95% CI: 0.98–0.99) in the past year was inversely associated with cataract likelihoods in older adults and a positive association between temperature (OR: 1.04; 95%CI: 1.03,1.05) in the past year and cataract likelihoods in older adults. The associations were robust in stratified analyses by sex, urban/rural residence, and education level. Furthermore, we found a nonlinear J-shaped relationship between temperature and cataract prevalence.

Conclusion

Our findings provide the evidence that higher temperature and low relative humidity may be associated with cataracts in older adults.

Dry eye disease and proteomics

Dry eye disease (DED) is a highly prevalent disease worldwide mostly associated with age, though other factors such as screen use and contact lens wear explain why it is increasingly diagnosed in younger people. DED also disproportionately affects women. Symptoms include eye dryness, burning, pain and sensitivity to light that can significantly affect quality of life. This condition may progress to cause lasting damage to the ocular surface if left untreated. Currently, diagnosis is through assessment of signs and symptoms determined by clinical tests and questionnaires. However, there is considerable overlap between normal and DED result distributions of currently available metrics as signs and symptoms fluctuate over time and with disease severity. Importantly, the non-targeted approach of proteomics means that significant changes in novel proteins may be discovered. Proteomics is a powerful tool that has been applied to the field of DED to understand changes at a biochemical level, uncover new disease biomarkers and determine the success of clinical interventions. While individual proteins may not be sensitive enough when used as single biomarkers, proteomics opens the possibility to uncover several relevant proteins that may be combined in a panel to provide more accurate diagnostic value i.e. parallel testing. In this review we discuss the use of proteomics in DED research and the potential for application of proteomic results in the clinic. We also identify shortcomings and future avenues for research.

Association between air pollution and emergency room visits for eye diseases and effect modification by temperature in Beijing, China

The growing burden of eye disease worldwide has aroused increasing concern upon its environmental etiology. This study aims to evaluate the associations of air pollutants with emergency room visits for eye diseases and the effect modification by temperature. Based on 24,389 cases from a general hospital during 2014-2019 in Beijing, China, this study used generalized additive models to examine the associations of air pollutants and emergency room visits for total eye diseases (ICD10: H00-H59) and conjunctivitis (ICD10: H10). Short-term exposures to PM2.5, PM10, CO, and NO2 were associated with increased visits for total eye diseases and conjunctivitis, and stronger effect estimates were observed in high (>75th) temperature group for PM2.5, PM10, CO, and NO2 and low (<75th) temperature group for CO and NO2. For instance, a 10 μg/m3 increase in PM2.5 at lag0-1 were associated with a 0.73% (95% CI: 0.23%, 1.24%) increase in total eye disease visits and a 1.34% (95% CI: 0.55%, 2.13%) increase in conjunctivitis visits, respectively. Meanwhile, a 10 μg/m3 increase in PM2.5 was associated with a 1.57% (95% CI: 0.49%, 2.64%) change in high temperature group and a 0.48% (95% CI: -0.24%, 1.19%) change in medium temperature group (P for interaction = 0.04) in total eye disease visits. Our study emphasizes the importance of controlling the potential hazards of air pollutants on eyes, especially on days with relatively higher or colder temperature.

Associations between Biomarkers of Metal Exposure and Dry Eye Metrics in Shipyard Welders: A Cross-Sectional Study

Shipyard welders are often exposed to welding metal fumes. Ocular surfaces are continually exposed to environmental hazards. However, limited information on the associations between metal exposure and dry eye metrics in occupational settings is available. This study employed a cross-sectional design that involved the participation of 59 welders and 25 administrative staff in a shipyard in northern Taiwan from September 2020 to October 2020. The participants' individual information, laboratory data, exposure to particulate matter < 2.5 μm, urinary, and toenail metal concentrations were collected. Dry eye metrics were evaluated using standardized questionnaires and a noninvasive ocular surface analyzer. Urinary V and Cr and toenail V, Cr, Mn, Fe, Ni, Zn, As, and Cd and Pb were significantly higher in the exposed group than in the control group. After adjustment for confounding factors, dry eye metrics were associated with urinary Cd (β = 0.407; p = 0.007) and toenail Pb (β = 0.482; p = 0.002). The participants with higher urinary Cd exhibited higher odds ratios for elevated dry eye metrics. Our study revealed that exposure to welding procedures increases several metal biomarkers. In addition, urinary Cd, and toenail Pb might be related to dry eye disease in shipyard welders.

A Novel Rat Model of Dry Eye Induced by Aerosol Exposure of Particulate Matter

Purpose

The purpose of this study was to introduce a novel dry eye rat model induced by aerosol exposure of particulate matter (PM).

Methods

A total of 30 female Sprague Dawley (SD) rats divided into 3 groups: the control group, the low-level exposed group, and the high-level exposed group. The rats in the experience groups were directly exposed to PM samples in the exposure chamber over 14 days. The clinical observation, including tear volume, corneal fluorescein staining, breakup time (BUT), inflammation index, corneal irregularity score, and corneal confocal microscopy. Eyeballs were collected on day 14 for hematoxylin and eosin (H&E) staining and PAS staining. TUNEL assay, CD45, and Ki67 immunostaining was performed and corneal ultrastructural changes were detected by electron microscopy. IL-1β, TNF-α, IFN-γ, and NF-κB Western blot analysis were used to observe the possible pathogenesis.

Results

In the PM-treated groups, the number of layers in the corneal epithelium and corneal nerve fiber length were significantly decreased compared with that of the control group. The number of corneal epithelial microvilli and chondriosome/desmosomes were drastically reduced in PM-treated groups. Confocal microscopy and CD45 immunohistochemistry showed inflammatory cell infiltration in the PM-treated groups. PM caused apoptosis of corneal and conjunctival epithelial cells while leading to abnormal epithelial cell proliferation, meanwhile, conjunctival goblet cells in the PM-treated group were also significantly reduced. PM significantly increased the levels of IL-1β, TNF-α, IFN-γ, and p-NF-κB-p65 in the cornea.

Conclusions

Aerosol exposure of PM can reduce the stability of tear film and cause the change of ocular surface, which is similar to the performance of human dry eye, suggesting a novel animal model of dry eye.

Low ambient temperature correlates with the severity of dry eye symptoms

PURPOSE:

The symptoms of dry eye disease (DED) are influenced by environmental factors, but the effect of ambient temperature is less certain. Our purpose was to investigate the relationship between the severity of DED symptoms and the ambient temperature.

MATERIALS AND METHODS:

This retrospective study reviewed the symptom scores, including ocular surface disease index (OSDI) and standardized patient evaluation of eye dryness (SPEED), as well as tear film parameters of first-time DED patients between June 2018 and June 2019. The contribution of tear film parameters and environmental factors, including ambient temperature, humidity, wind speed, and the concentration of air pollutants, to the severity of dry eye symptoms was evaluated by univariate and multivariate linear regression analyses.

RESULTS:

There were 351 patients included aged 52.8 ± 13.6 years, and 257 (73.2%) were female. The average tear film break-up time, Schirmer test value, and lipid layer thickness were 2.6 ± 0.7 s, 5.5 ± 4.3 mm, and 64.1 ± 6.0 μm, respectively. The average OSDI and SPEED were 41.8 ± 19.8 and 12.1 ± 5.1, respectively. In winter, the patients reported higher OSDI and SPEED. Both scores were significantly correlated with low ambient temperature. Regression analysis showed that low ambient temperature and Schirmer test value contributed to higher OSDI, while low ambient temperature and younger age contributed to higher SPEED.

CONCLUSION:

Low ambient temperature plays a significant role in DED symptom severity.

Association between outpatient visits for pterygium and air pollution in Hangzhou, China

Air pollution could be a risk factor for the development of pterygium. This study aimed to investigate the potential associations between outpatient visits for pterygium and air pollutants. Using a time-stratified case-crossover design, the data of 3017 outpatients with pterygium visiting an eye center in Hangzhou, China, and the air pollution data of the Environmental Protection Department of Zhejiang Province between July 1, 2014, and November 30, 2019, were examined. The relationships between the air pollutants nitrogen dioxide (NO₂), sulfur dioxide (SO₂), ozone, and fine particulate matter (PM) with median aerometric diameter <2.5 μm (PM_2.5) and <10 μm (PM₁₀) and outpatient visits for primary pterygium were assessed using single- and multiple-pollutant models. Significant associations between outpatient visits for pterygium and air pollutants (PM_2.5, PM₁₀, SO₂, and NO₂) were observed. Younger patients were found to be more sensitive to air pollution. Interestingly, the younger female patients with pterygium were more vulnerable to PM_2.5 exposure during the warm season, while the younger male patients with pterygium were more sensitive to NO₂ during the cold season. Significant effects were also observed between the pterygium outpatients and PM_2.5 (odds ratio [OR] = 1.06, P = 0.02), PM₁₀ (OR = 1.04, P = 0.01), and SO₂ (OR = 1.26, P = 0.01) during the warm season, as well as NO₂ (OR = 1.06, P = 0.01) during the cold season. Our study provides evidence that outpatient visits for pterygium are positively associated with increases in the air pollutants PM_2.5, PM₁₀, SO₂, and NO₂, revealing the important role of air pollution in the occurrence and development of pterygium.

Artificial intelligence in dry eye disease

Dry eye disease (DED) has a prevalence of between 5 and 50%, depending on the diagnostic criteria used and population under study. However, it remains one of the most underdiagnosed and undertreated conditions in ophthalmology. Many tests used in the diagnosis of DED rely on an experienced observer for image interpretation, which may be considered subjective and result in variation in diagnosis. Since artificial intelligence (AI) systems are capable of advanced problem solving, use of such techniques could lead to more objective diagnosis. Although the term 'AI' is commonly used, recent success in its applications to medicine is mainly due to advancements in the sub-field of machine learning, which has been used to automatically classify images and predict medical outcomes. Powerful machine learning techniques have been harnessed to understand nuances in patient data and medical images, aiming for consistent diagnosis and stratification of disease severity. This is the first literature review on the use of AI in DED. We provide a brief introduction to AI, report its current use in DED research and its potential for application in the clinic. Our review found that AI has been employed in a wide range of DED clinical tests and research applications, primarily for interpretation of interferometry, slit-lamp and meibography images. While initial results are promising, much work is still needed on model development, clinical testing and standardisation.