Medical Treatment for Dry Eye in Japan

TRPV4 activation in human corneal epithelial cells promotes membrane mucin production

Given that the corneal epithelium is situated on the outermost part of the eye, its functions can be influenced by external temperatures and chemical substances. This study aimed to elucidate the expression profile of chemosensory receptors in corneal epithelial cells and analyze their role in eye function regulation. A comprehensive analysis of 425 chemosensory receptors in human corneal epithelial cells-transformed (HCE-T) revealed the functional expression of TRPV4. The activation of TRPV4 in HCE-T cells significantly increased the expression of membrane-associated mucins MUC1, MUC4, and MUC16, which are crucial for stabilizing tear films, with efficacy comparable to the active components of dry eye medications. The present study suggests that TRPV4, which is activated by body temperature, regulates mucin expression and proposes it as a novel target for dry eye treatment.

Comparing two mucin secretagogues for the treatment of dry eye disease: a prospective randomized crossover trial

This study aimed to compare the clinical efficacy and investigate patients' preferences for two mucin secretagogues in the treatment of dry eye disease (DED). Thirty patients with DED were randomly treated with either 3% diquafosol or 2% rebamipide ophthalmic solution for 4 weeks, followed by an additional 4-week treatment using the other eye drop after a 2-week washout period. Objective and subjective assessments, including the corneal and conjunctival staining score, tear breakup time (TBUT), Schirmer 1 test, tear osmolarity, tear matrix metalloproteinase-9 (MMP-9), lipid layer thickness (LLT) and ocular surface disease index (OSDI), were performed at baseline, 4 weeks, 6 weeks, and 10 weeks. Patient preferences were assessed based on four categories (comfort, efficacy, convenience, willingness to continue) using a questionnaire and the overall subjective satisfaction score for each drug was obtained at the end of the trial. In total, 28 eyes from 28 patients were included in the analysis. Both diquafosol and rebamipide significantly improved the OSDI (p = 0.033 and 0.034, respectively), TBUT (p < 0.001 and 0.026, respectively), and corneal (p < 0.001 and 0.001, respectively) and conjunctival (p = 0.017 and 0.042, respectively) staining after 4 weeks of treatment. An increase in Schirmer test scores was observed only after rebamipide treatment (p = 0.007). No significant changes were detected in tear osmolarity, MMP-9, and LLT following both treatments. The patients' preference was slightly greater for diquafosol (46.4%) than rebamipide (36.7%), presumably due to rebamipide's bitter taste. The self-efficacy of both drugs and overall satisfaction scores were comparable. These findings indicate that two mucin secretagogues showed comparable effects in ameliorating symptoms and improving signs (TBUT, corneal and conjunctival staining) in patients with DED.

The Conjunctival Microbiome and Dry Eye: What We Know and Controversies

ABSTRACT

Dry eye disease is a common multifactorial condition that may be idiopathic or associated with autoimmune conditions, such as Sjogren syndrome. Commensal microorganisms modify immune responses, so it is relevant to understand how they modify such immune-mediated diseases. Microbiota in the gut regulate inflammation in the eye, and conversely, severe inflammation of the ocular surface results in alteration of gut microbiome. The conjunctiva microbiome can be analyzed using 16S or shotgun metagenomics. The amount of microbial DNA in ocular surface mucosa relative to human DNA is limited compared with the case of the intestinal microbiome. There are challenges in defining, harvesting, processing, and analyzing the microbiome in the ocular surface mucosa. Recent studies have shown that the conjunctiva microbiome depends on age, presence of local and systemic inflammation, and environmental factors. Microbiome-based therapy, such as the use of oral probiotics to manage dry eye disease, has initial promising results. Further longitudinal studies are required to investigate the alteration of the conjunctival microbiome after local therapy and surgery.

Therapeutic applications of carbohydrate-based compounds: a sweet solution for medical advancement

Carbohydrates, one of the most abundant biomolecules found in nature, have been seen traditionally as a dietary component of foods. Recent findings, however, have unveiled their medicinal potential in the form of carbohydrates-derived drugs. Their remarkable structural diversity, high optical purity, bioavailability, low toxicity and the presence of multiple functional groups have positioned them as a valuable scaffold and an exciting frontier in contemporary therapeutics. At present, more than 170 carbohydrates-based therapeutics have been granted approval by varying regulatory agencies such as United States Food and Drug Administration (FDA), Japan Pharmaceuticals and Medical Devices Agency (PMDA), Chinese National Medical Products Administration (NMPA), and the European Medicines Agency (EMA). This article explores an overview of the fascinating potential and impact of carbohydrate-derived compounds as pharmacological agents and drug delivery vehicles.

Carbohydrate-based drugs launched during 2000-2021

Carbohydrates are fundamental molecules involved in nearly all aspects of lives, such as being involved in formating the genetic and energy materials, supporting the structure of organisms, constituting invasion and host defense systems, and forming antibiotics secondary metabolites. The naturally occurring carbohydrates and their derivatives have been extensively studied as therapeutic agents for the treatment of various diseases. During 2000 to 2021, totally 54 carbohydrate-based drugs which contain carbohydrate moities as the major structural units have been approved as drugs or diagnostic agents. Here we provide a comprehensive review on the chemical structures, activities, and clinical trial results of these carbohydrate-based drugs, which are categorized by their indications into antiviral drugs, antibacterial/antiparasitic drugs, anticancer drugs, antidiabetics drugs, cardiovascular drugs, nervous system drugs, and other agents.

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.

Safety and efficacy of pilocarpine, cevimeline, and diquafosol compared to artificial tears for the treatment of dry eye: protocol for a systematic review

BACKGROUND

Dry eye disease (DED) is a condition that compromises the ocular surface and affects millions of people around the world. In recent years, a scheme has been proposed for the treatment of DED, with the use of artificial tear being the mainstay of treatment. In this scheme, the use of secretagogues is suggested as part of the treatment for patients with moderate to severe affectation. With this systematic review, we aim to evaluate the effectiveness and safety of secretagogues for DED.

METHODS

Electronic databases will be searched; we will include randomized controlled trials that compare secretagogues and artificial tears. Study inclusion will not be restricted on the basis of language or publication status. We will use Google Translate to assess studies written in languages other than English and Spanish. Identification, evaluation, data extraction, and assessment of risk of bias will be conducted by two authors of the review, a third review author will resolve any disagreement. The outcomes will be the ocular surface disease index score, tear film break-up time, Schirmer test score, VRQoL Score, and tear film osmolarity. We will use the Cochrane Collaboration Risk of Bias 2 (RoB 2) tool for assessing the risk of bias of the included studies. Based on the heterogeneity of the included studies, we will combine the findings in a meta-analysis using a fixed effect model if heterogeneity ≤ 50% or a random effect model if heterogeneity > 50%. If we deem meta-analysis as inappropriate, we will document the reasons and report findings from the individual studies narratively.

DISCUSSION

Based on the evidence obtained, we will evaluate the effect of pilocarpine, cevimeline, and diquafosol and compare it to artificial tears on multiple outcome measures. This systematic review aims to determine the efficacy and safety of the secretagogues pilocarpine, cevimeline, and diquafosol to help clinicians in the decision-making process.

TRIAL REGISTRATION

PROSPERO CRD42020218407 .

Eye drops for dry eye disease during pregnancy and adverse neonatal outcomes: high-dimensional propensity score analyses

We investigated the association between exposure to eye drops prescribed for dry eye disease (DED) during pregnancy and adverse neonatal outcomes. Pregnant women with DED in the JMDC Claims Database (JMDC Inc., Tokyo, Japan) between 2005 and 2020 were included. According to their prescriptions during the first trimester, the women were classified into three exposed groups (hyaluronate 0.1% alone, hyaluronate 0.3% alone, and diquafosol alone) and an unexposed group (no eye drops for DED). We compared adverse neonatal outcomes (congenital anomalies, preterm birth, low birthweight, and composite outcome of these three) between the exposed and unexposed groups. We conducted a high-dimensional propensity score analysis using many variables in the database together with known potential confounders such as chronic comorbidities. We identified 4,808 eligible women, of whom 936 (19.5%) received eye drops for DED. Congenital anomalies occurred in 7.2% and 6.0%, preterm birth in 3.1% and 4.0%, low birthweight in 7.9% and 6.0%, and composite outcome in 14.9% and 12.3% of women in the hyaluronate 0.1% alone and unexposed groups, respectively. The high-dimensional propensity score analysis showed that hyaluronate 0.1% alone was not significantly associated with increases in congenital anomalies (risk difference, 0.4% [95% confidence interval, -1.9% to 2.7%]), preterm birth (-0.6% [-2.2% to 0.9%]), low birthweight (1.8% [-0.6% to 4.1%]), or composite outcome (1.9% [-1.3% to 5.1%]). Similar results were obtained in the hyaluronate 0.3% alone and diquafosol alone groups. Use of eye drops for DED in pregnant women was not associated with adverse neonatal outcomes.

Trends in Topical Prescriptional Therapy for Old Patients With Dry Eye Disease in Six Major Areas of China: 2013-2019

The prevalence of dry eye disease (DED) in old patients are high, corresponding to a substantial economic burden. In this cross-sectional study, we analyzed the trends in the topical prescriptional treatment of old patients with DED in six major areas of China. Information on topical drug prescriptions for DED patients aged above 60 years was extracted from the Hospital Prescription Analysis Cooperative Program of China database. Trends in yearly prescriptions and cost were analyzed. The data were further stratified by patient age and sex, drug class, and specific drug. A total of 130,734 prescriptions from 52 hospitals located in six major areas of China were analyzed. The number of prescripptions per year for patients with DED increased from 13,308 in 2013 to 22,074 in 2019, with a corresponding increase in cost of all topical drugs from 1,490,014 Chinese Yuan (CNY) to 2,618,206 CNY. Drugs for the treatment of DED accounted for the largest proportion of the total cost in each year. Ocular lubricants were the main pharmacotherapy agent. Sodium hyaluronate use increased over time, and the drug was used by 65.9% of patients by the end of the study. Pranoprofen was the second most frequently used drug. The most frequently used drugs for co-incident disease were antimicrobials. Treatment patterns for DED haven’t changed, and the most frequently used drug combination was sodium hyaluronate and pranoprofen. In summary, prescription for old patients with DED and the cost of treatment are increasing. Ocular lubricants are the main treatment option, while sodium hyaluronate is the most frequently used drug. The observed trends can lead to more efficient allocation of health care resources in China.

Heterogeneity of eye drop use among symptomatic dry eye individuals in Japan: large-scale crowdsourced research using DryEyeRhythm application

PURPOSE

To determine eye drop type and usage frequency and investigate risk factors for no eye drop use in individuals with symptomatic dry eye (DE) in Japan.

STUDY DESIGN

Crowdsourced observational study.

METHODS

This study was conducted using the DryEyeRhythm smartphone application between November 2016 and September 2019. Data collected included the type and frequency of eye drop use, demographics, medical history, lifestyle, and self-reported symptoms. Symptomatic DE was defined as an Ocular Surface Disease Index total score of ≥ 13. Risk factors for no eye drop use were identified using multivariate logistic regression analyses.

RESULTS

Among 2619 individuals with symptomatic DE, 1876 did not use eye drops. The most common eye drop type was artificial tears (53.4%), followed by hyaluronic acid 0.1% (33.1%) and diquafosol sodium 3% (18.7%). Risk factors (odds ratio [95% confidence interval]) for no eye drop use were age (0.97 [0.97-0.98]), body mass index (1.04 [1.01-1.07]), brain disease (0.38 [0.15-0.98]), collagen disease (0.30 [0.13-0.68]), mental illness other than depression and schizophrenia (0.65 [0.45-0.93]), cataract surgery (0.12 [0.02-0.59]), ophthalmic surgery other than cataract and laser-assisted in situ keratomileusis (0.55 [0.34-0.88]), current (0.47 [0.38-0.57]) or past (0.58 [0.43-0.77]) contact lens use, >8 h screen exposure time (1.38 [1.05-1.81]), <6 h (1.24 [1.01-1.52]) and >9 h (1.34 [1.04-1.72]) sleep time, and water intake (0.97 [0.94-0.98]).

CONCLUSION

Many participants with symptomatic DE did not use optimized eye drop treatment and identified risk factors for no eye drop use. The DryEyeRhythm application may help improve DE treatment.

Cataract surgery and dry eye disease: A review

AIM

To review published literature concerning cataract surgery and dry eye disease (DED).

METHODS

A search was undertaken using the following: PubMed (all years), Web of Science (all years), Ovid MEDLINE(R) (1946 to 12 December 2019), Ovid MEDLINE(R) Daily Update 10 December 2019, MEDLINE and MEDLINE non-indexed items, Embase (1974-2019, week 49), Ovid MEDLINE (R) and Epub Ahead of Print, In-Process and Other Non-Indexed Citations and Daily (1946 to 12 December 2019), CENTRAL (including Cochrane Eyes and Vision Trials Register; Cochrane Library: Issue 12 of 12 December 2019), metaRegister of Controlled Trials (mRCT) (www.controlled-trials.com), ClinicalTrials.gov (www.clinicaltrial.gov) and WHO International Clinical Trials Registry Platform (www.who.int/ictrp/search/en). Search terms included 'cataract surgery', 'phacoemulsification' and 'cataract extraction', combined with 'dry eyes' and 'ocular surface'. Relevant in-article references not returned in our searches were also considered.

RESULTS

Publications identified included systematic reviews, meta-analysis, randomized controlled trials, cohort studies, case series and laboratory-based studies. Published data highlighting the burden of DED both prior and following cataract surgery were reviewed as well as studies highlighting the effects of cataract surgery on the ocular surface, intra-operative measures to reduce deleterious effects on the ocular surface and current evidence on the management options of post-operative DED.

CONCLUSIONS

DED is common and can be exacerbated by cataract surgery. Ophthalmologists need to assess for pre-existing DED and instigate treatment before surgery; be aware of reduced accuracy of measurements for surgical planning in the presence of DED; limit intra-operative surgical factors damaging to the ocular surface; and consider management to reduce DED post-operatively.

Impact of Attrition, Intercellular Shear in Dry Eye Disease: When Cells are Challenged and Neurons are Triggered

The mechanical component in the pathophysiology of dry eye disease (DED) deserves attention as an important factor. The lubrication deficit induced impaired mechano-transduction of lid pressure to the ocular surfaces may lead to the dysregulation of homeostasis in the epithelium, with sensations of pain and secondary inflammation. Ocular pain is possibly the first sign of attrition and may occur in the absence of visible epithelial damage. Attrition is a process which involves the constant or repeated challenge of ocular surface tissues by mechanical shear forces; it is enhanced by the thinning of corneal epithelium in severe DED. As a highly dynamic process leading to pain and neurogenic inflammation, the identification of the impact of attrition and its potential pathogenic role could add a new perspective to the current more tear film-oriented models of ocular surface disease. Treatment of DED addressing lubrication deficiencies and inflammation should also consider the decrease of attrition in order to stimulate epithelial recovery and neural regeneration. The importance of hyaluronic acid, its molecular characteristics, the extracellular matrix and autoregulative mechanisms in this process is outlined. The identification of the attrition and recognition of its impact in dry eye pathophysiology could contribute to a better understanding of the disease and optimized treatment regimens.