n-3 Fatty Acid Supplementation for the Treatment of Dry Eye Disease

The Protective Effect of Polyunsaturated Fatty Acids against Dry Eye Disease: A Literature Review

Dry eye disease (DED) is a common disease, and have an adverse effect the physical, functional, and psychological quality of life. It is a multifactorial disorder characterized by the loss of tear film homeostasis, in which self-perpetuating vicious cycle leads to deterioration of function and inflammation of the lacrimal functional unit. Hence, treatment strategies should be aimed at the interruption of the vicious inflammatory cycle and alleviation of ocular surface inflammation. Anti-inflammatory therapies have been shown to improve the signs and symptoms of the disease. Evidence indicates that polyunsaturated fatty acids (PUFAs) may contribute to reinforcement of innate anti-inflammatory mechanisms, and systemic and topical administration of PUFAs may help modulate ocular surface inflammation. In the present review, the authors will introduce the results of clinical and experimental studies to elucidate the mechanism, efficacy, and safety of systemic and topical supplementation with PUFAs as an alternative therapeutic strategy for DED. This review will also include discussion regarding current perspectives, including evidence-based recommendations and possible side effects of PUFAs supplementation. The review of the literature suggests that PUFAs supplementation can be a viable option for the treatment of DED, although further studies are needed for establishment of treatment guidelines.

Seafood and health: What you need to know?

Seafood, including fish and shellfish, provides an ideal package of nutrients and is an important part of a healthy diet. Strong evidence has shown that eating fish and other seafoods improve brain, eye, and heart health. The new 2020-2025 Dietary Guidelines for Americans (DGA) recommend that Americans of all ages should eat more seafood-at least twice a week-particularly pregnant women and young children. However, less than one in five Americans heed that advice. About one-third of Americans eat seafood once a week, while nearly half eat fish only occasionally or not at all. This calls for a drastic shift in the American diet to vary protein sources and include more seafood products in order to receive the most health benefits. This chapter covers (1) seafood nutrition and health benefits, (2) seafood's protective effects against mercury toxicity, (3) selenium health benefit values (HBVs), and (4) challenges and opportunities for seafood production, demand and sustainability. This chapter aims to convey recent advances in science-based information to increase public awareness of seafood safety, nutrition and health benefits of seafood as part of a healthy diet, and to advocate healthy eating with smart food choices by promoting two servings of seafood per week. This will support the healthy eating patterns and promotes a minimum two to three servings of seafood recommended by the current DGA.

Modern approach to the treatment of dry eye, a complex multifactorial disease: a P.I.C.A.S.S.O. board review

Dry eye disease (DED) is a growing public health concern affecting quality of life and visual function, with a significant socio-economic impact. It is characterised by the loss of homoeostasis, resulting in tear film instability, hyperosmolarity and inflammation of the ocular surface. If the innate immune response is unable to cope with internal bodily or environmental adverse conditions, the persistent, self-maintaining vicious circle of inflammation leads to the chronic form of the disease. Treatment of DED should be aimed at the restoration of the homoeostasis of the ocular surface system. A proper diagnostic approach is fundamental to define the relevance and importance of each of the DED main pathogenic factors, namely tear film instability, epithelial damage and inflammation. Consideration also needs to be given concerning two other pathogenic elements: lid margin changes and nerve damage. All the factors that maintain the vicious circle of DED in the patient's clinical presentation have to be considered and possibly treated simultaneously. The treatment should be long-lasting and personalised since it has to be adapted to the different clinical conditions observed along the course of the disease. Since DED treatment is frequently unable to provide fast and complete relief from symptoms, empathy with patients and willingness to explain to them the natural history of the disease are mandatory to improve patients' compliance. Furthermore, patients should be instructed about the possible need to increase the frequency and/or change the type of treatment according to the fluctuation of symptoms, following a preplanned rescue regimen.

Systemic Conditions Associated with Severity of Dry Eye Signs and Symptoms in the Dry Eye Assessment and Management Study

PURPOSE

Certain systemic conditions are reported to be risk factors for dry eye disease (DED), but their associations with DED severity are not well studied. We evaluated whether systemic conditions reported to be DED risk factors are associated with severity of DED signs and symptoms.

DESIGN

Secondary analysis of data from the Dry Eye Assessment and Management Study, a large-scale multicenter randomized clinical trial of patients with moderate to severe DED.

PARTICIPANTS

Five hundred thirty-five adult patients with moderate to severe DED from 27 United States centers.

METHODS

Patients reported their medical history at baseline. They underwent ocular surface examinations and symptom evaluation using standardized protocols at baseline, 6 months, and 12 months. We analyzed the associations of systemic conditions (a systemic disease or smoking history) reported as potential DED risk factors with the severity of DED signs and symptoms using generalized linear regression models adjusted by age, gender, race, and visit.

MAIN OUTCOME MEASURES

Dry eye disease symptoms assessed using the Ocular Surface Disease Index (OSDI), 6 DED signs (tear film break-up time, anesthetized Schirmer testing, corneal fluorescein staining, conjunctival lissamine green staining, tear osmolarity, and meibomian gland dysfunction), and a composite signs severity score from 0 to 1 (1 = most severe).

RESULTS

The mean age was 58 years; 81% were women. More severe DED signs were associated significantly with Sjögren syndrome (mean composite signs severity score 0.52 with disease vs. 0.43 without disease; P < 0.001), facial rosacea (0.47 vs. 0.43; P = 0.002), rheumatoid arthritis (0.47 vs. 0.42; P = 0.002), peripheral artery disease (0.50 vs. 0.43; P < 0.001), and daily smoking history (0.45 vs. 0.43; P = 0.047). Thyroid dysfunction, osteoarthritis, diabetes, irritable bowel syndrome, hypercholesterolemia, hypertension, and hypertriglyceridemia were not associated significantly with DED signs. No conditions were associated significantly with OSDI.

CONCLUSIONS

In this large, well-characterized cohort of patients with DED assessed under standardized procedures, patients with certain systemic diseases and smoking history showed more severe DED signs compared with patients without the conditions. The profile of significant DED signs varied by systemic condition, reflecting different DED causes. Understanding the systemic conditions and underlying causes that predispose some patients to severe DED can improve management.

Ocular complications of perioperative anesthesia: a review

Ocular complications associated with anesthesia in ocular and non-ocular surgeries are rare adverse events which may present with clinical presentations vacillating between easily treatable corneal abrasions to more serious complication such as irreversible bilateral vision loss. In this review, we outline the different techniques of anesthetic delivery in ocular surgeries and highlight the incidence and etiologies of associated injuries. The changes in vision in non-ocular surgeries are mistaken for residual sedation or anesthetics, therefore require high clinical suspicion on part of the treating ophthalmologists, to ensure early diagnosis, adequate and swift management especially in surgeries such as cardiac, spine, head and neck, and some orthopedic procedures, that have a comparatively higher incidence of ocular complications. In this article, we review the literature for reports on the clinical incidence of different ocular complications associated with anesthesia in non-ocular surgeries and outline the current understanding of pathophysiological processes associated with these adverse events.

From Fish Waste to Value: An Overview of the Sustainable Recovery of Omega-3 for Food Supplements

The disposal of food waste is a current and pressing issue, urging novel solutions to implement sustainable waste management practices. Fish leftovers and their processing byproducts represent a significant portion of the original fish, and their disposal has a high environmental and economic impact. The utilization of waste as raw materials for the production of different classes of biofuels and high-value chemicals, a concept known as "biorefinery", is gaining interest in a vision of circular economy and zero waste policies. In this context, an interesting route of valorization is the extraction of omega-3 fatty acids (ω-3 FAs) for nutraceutical application. These fatty acids, such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) have received attention over the last decades due to their beneficial effects on human health. Their sustainable production is a key process for matching the increased market demand while reducing the pressure on marine ecosystems and lowering the impact of waste production. The high resale value of the products makes this waste a powerful tool that simultaneously protects the environment and benefits the global economy. This review aims to provide a complete overview of the sustainable exploitation of fish waste to recover ω-3 FAs for food supplement applications, covering composition, storage, and processing of the raw material.

Docosanoid signaling modulates corneal nerve regeneration: effect on tear secretion, wound healing, and neuropathic pain

The cornea is densely innervated, mainly by sensory nerves of the ophthalmic branch of the trigeminal ganglia (TG). These nerves are important to maintain corneal homeostasis, and nerve damage can lead to a decrease in wound healing, an increase in corneal ulceration and dry eye disease (DED), and neuropathic pain. Pathologies, such as diabetes, aging, viral and bacterial infection, as well as prolonged use of contact lenses and surgeries to correct vision can produce nerve damage. There are no effective therapies to alleviate DED (a multifunctional disease) and several clinical trials using ω-3 supplementation show unclear and sometimes negative results. Using animal models of corneal nerve damage, we show that treating corneas with pigment epithelium-derived factor plus DHA increases nerve regeneration, wound healing, and tear secretion. The mechanism involves the activation of a calcium-independent phospholipase A2 that releases the incorporated DHA from phospholipids and enhances the synthesis of the docosanoids, neuroprotectin D1 (NPD1) and a new resolvin stereoisomer, resolvin D6i (RvD6i). NPD1 stimulates the synthesis of brain-derived neurotrophic factor, nerve growth factor, and semaphorin 7A. RvD6i treatment of injured corneas modulates gene expression in the TG resulting in enhanced neurogenesis, decreased neuropathic pain, and increased sensitivity. Taken together, these results represent a promising therapeutic option to reestablish the homeostasis of the cornea.

Ocular manifestations of rosacea: A clinical review

Ocular rosacea is a chronic inflammatory condition that can occur in the absence of cutaneous features. The most common ocular features are chronic blepharoconjunctivitis with eyelid margin inflammation and meibomian gland dysfunction. Corneal complications include corneal vascularization, ulceration, scarring and, rarely, perforation. Diagnosis is largely based on clinical signs, although it is often delayed in the absence of cutaneous changes, particularly in children. It can also be associated with systemic disorders such as cardiovascular disease. Management ranges from local therapy to systemic treatment, depending on the severity of the disease. In this review, we describe the epidemiology, pathophysiology, clinical features and treatment of rosacea and ocular rosacea.

Risk Factors Influencing the Occurrence and Severity of Symptomatic Dry Eye Syndrome: A Cross-sectional Study

Propose: We aimed to investigate the prevalence and risk factors of dry eye syndrome (DES) among a population-based cohort study.Methods: This cross-sectional study was conducted on 475 subjects (184 men and 291 women) enrolled in the Study Group for Environmental Eye Disease at July 2013. Using the ocular surface disease index (OSDI), we measured the DES severity and defined DES as OSDI score ≥13. Current symptoms of DES and possible risk factors such as body mass index, occupations, comorbidities, exercise, smoking and drinking status were assessed by multivariate logistic regression.Results: Prevalence of DES was significantly higher in women (52.6%) than in men (41.9%) (p < .001). Compared to white-collar workers, blue-collar workers and unemployed persons showed significantly higher DES prevalence and severity. Compared to those with low BMI (<23.0 kg/m²), people with extremely high BMI (≥30.0 kg/m²) had significantly higher odds ratio (OR) of having DES after fully adjusted for sex, age, hypertension, diabetes, menopausal status, hormone replacement therapy, occupation, and lifestyle factors (OR: 2.83, 95% confidence interval: 1.04-7.71).Conclusions: We found some novel factors which have been unknown to the relationship with DES through the five years observation of the cohort. The positive associations of unemployment status, blue-collar work, alcohol habit, and obesity with DES suggests a person's comprehensive condition, not individual factors, contribute significantly in developing DES. Further studies will be helpful to understand the underlying mechanisms.

Relation of Dietary Fatty Acids and Vitamin D to the Prevalence of Meibomian Gland Dysfunction in Japanese Adults: The Hirado-Takushima Study

Intervention studies have shown that n-3 polyunsaturated fatty acid (PUFA) supplementation is effective for the treatment of meibomian gland dysfunction (MGD). Ointment containing an analog of vitamin D has also been found to improve symptoms and signs of MGD. We have now evaluated the relation of MGD prevalence to dietary intake of fatty acids (FAs) and vitamin D among a Japanese population. Subjects comprised 300 adults aged 20 to 92 years residing on Takushima Island. MGD was diagnosed on the basis of subjective symptoms, lid margin abnormalities, and meibomian gland obstruction. Dietary FA and vitamin D intake was estimated with a brief-type self-administered diet history questionnaire. MGD prevalence was 35.3%. Multivariate adjusted odds ratios (95% confidence intervals) between extreme quintiles of intake for MGD prevalence were 0.40 (0.16–0.97) for total fat, 0.40 (0.17–0.97) for saturated FAs, 0.40 (0.17–0.97) for oleic acid, 0.52 (0.23–1.18) for n-3 PUFAs, 0.63 (0.27–1.49) for n-6 PUFAs, 1.32 (0.59–2.95) for the n-6/n-3 PUFA ratio, and 0.38 (0.17–0.87) for vitamin D. Total fat, saturated FA, oleic acid, and vitamin D intake may thus be negatively associated with MGD prevalence in the Japanese.

An Evidence-Based Strategic Approach to Prevention and Treatment of Dry Eye Disease, a Modern Global Epidemic

Dry eye disease (DED) is an emerging health concern causing significant visual, psychological, social, and economic impact globally. In contrast to visual rehabilitation undertaken at late stages of DED, measures instituted to prevent its onset, establishment, or progression can alter its natural course and effectively bring down the associated morbidity. This review attempts to present the available literature on preventive strategies of DED at one place, including strategies for risk assessment and mitigation, targeting a wide range of population. A literature search was conducted using PubMed and an extensive literature review on preventive strategies for DED was compiled to put forth a holistic and strategic approach for preventing DED. This can be undertaken at various stages or severity of DED directed at different tiers of the health care system. Conclusion: This review intends to put emphasis on preventive strategies being adopted as an integral part of routine clinical practice by general ophthalmologists and specialists to tackle the burden of DED and improve the quality of the lives of the patients suffering from it.

Dorsolateral medullary infarction registry: a study protocol for a prospective, multicentric registry

Background

Dorsolateral medullary infarction is a typical cerebral infarction which is characterized by Wallenberg’s syndrome. Neurotrophic keratopathy is an uncommon consequence of dorsolateral medullary infarction. At present, the protocol is aimed to study the dynamic changes in corneal innervation and the ocular surface environment after dorsolateral medullary infarction.

Methods

This study will involve consecutive data from all medical records of patients within 7 days of acute dorsolateral medullary infarction onset at the Departments of Neurology from 10 collaborating stroke centers. Eligible patients will mainly be characterized based on detailed physical examinations, multimodal imaging, and corneal related examinations and patients will be followed-up for 2 years. Neurotrophic keratopathy after dorsolateral medullary infarction is the primary endpoint. The dynamic histological corneal innervation and ocular surface environment after dorsolateral medullary infarction will be observed during the follow-up period.

Discussion

This multicentric, prospective registry is the first to identify and characterize the dynamic changes of corneal innervation and the ocular surface environment after acute dorsolateral medullary infarction. The significance of the study is to emphasize that the curative effect is based on the doctors’ identification of the disease in the earliest stage before irreversible damage occurs to the cornea.

Trial registration

The registry was registered (ChiCTR-OPC-17,011,625) on June 11, 2017.

Stereoselective syntheses and biological activities of E-series resolvins

Recent research efforts focusing on the many mechanisms participating in the resolution of acute inflammation have uncovered a new genus of pro-resolving lipid mediators. These endogenous molecules include the lipoxins, resolvins, protectins and maresins, collectively coined specialized pro-resolving mediators (SPMs). SPMs are oxygenated polyunsaturated fatty acids biosynthesized by lipoxygenases and cyclooxygenases enzymes. These chemically sensitive molecules are produced in nano- to pico-gram amounts in vivo and exhibit potent anti-inflammatory and pro-resolving bioactions. In addition, SPMs clear bacterial infections, reduce pain and display bioactivities towards host defense, organ protection and tissue remodeling. Altogether, these bioactions and the need for synthetic SPMs for determination of absolute configuration and in vivo experiments have spurred a great interest in the synthetic and biomolecular communities. This review covers reported stereoselective total syntheses and outlines the most significant bioactions of the E-series resolvins.

Associations Between Systemic Omega-3 Fatty Acid Levels With Moderate-to-Severe Dry Eye Disease Signs and Symptoms at Baseline in the Dry Eye Assessment and Management Study

PURPOSE

Omega-3 (n-3) fatty acid supplementation is used to treat systemic inflammatory diseases, but the role of n-3 in the pathophysiology and therapy of dry eye disease (DED) is not definitive. We evaluated the relationship of systemic n-3 levels with signs and symptoms at baseline in the Dry Eye Assessment and Management (DREAM) Study.

METHODS

Blood samples from participants at baseline were analyzed for n-3 and n-6, measured as relative percentage by weight among all fatty acids in erythrocytes. Symptoms were evaluated using the Ocular Surface Disease Index. Signs including conjunctival staining, corneal staining, tear breakup time (TBUT), and Schirmer's test with anesthesia were also evaluated.

RESULTS

There was no correlation between the systemic n-3 levels and DED symptoms. When the associations with signs of DED were assessed, lower DHA levels were associated with higher conjunctival staining, with mean scores of 3.31, 2.96, and 2.82 for low, medium, and high levels of DHA, respectively (linear trend P=0.007). None of the other signs were associated with DHA or the other measures of n-3.

CONCLUSION

Previous studies have found varying results on the role of n-3 supplementation with the signs and symptoms of DED. Among patients with DED enrolled in the DREAM Study, lower systemic n-3 levels were not associated with worse symptoms and most signs of DED.

The potential of lipid mediator networks as ocular surface therapeutics and biomarkers

In the last twenty years an impressive body of evidence in diverse inflammatory animal disease models and human tissues, has established polyunsaturated fatty acids (PUFA) derived specialized-pro-resolving mediators (SPM), as essential mediators for controlling acute inflammation, immune responses, wound healing and for resolving acute inflammation in many non-ocular tissues. SPM pathways and receptors are highly expressed in the ocular surface where they regulate wound healing, nerve regeneration, innate immunity and sex-specific regulation of auto-immune responses. Recent evidence indicates that in the eye these resident SPM networks are important for maintaining ocular surface health and immune homeostasis. Here, we will review and discuss evidence for SPMs and other PUFA-derived mediators as important endogenous regulators, biomarkers for ocular surface health and disease and their therapeutic potential.

Management of Ocular Surface Disease in Glaucoma: A Survey of Canadian Glaucoma Specialists

PRéCIS:: Ocular surface disease (OSD) in glaucoma is an area for improvement in the management of patients with glaucoma. This study explores the knowledge of glaucoma subspecialists toward OSD in glaucoma, then provides a suggested treatment algorithm.

PURPOSE

To assess the attitudes, knowledge, and level of comfort of Canadian glaucoma specialists with respect to the assessment and management of OSD among patients with glaucoma.

METHODS

Ophthalmologist members of the Canadian Glaucoma Society with fellowship training in glaucoma were contacted to participate in this cross-sectional survey study. Responses were recorded to statements regarding attitudes toward OSD in glaucoma, and assessment and management modalities. These were recorded primarily in the form of a Likert scale rated 1 to 7 from "strongly disagree" to "strongly agree." Descriptive statistics were generated, and mean and SD for responses on Likert scales.

RESULTS

Thirty-six responses were included. All respondents agreed that comprehensive management of OSD could improve quality of life, 97% agreed it could lead to better glaucoma outcomes, whereas only 22% agreed it is presently being adequately managed in glaucoma practices. Respondents were asked to list all treatment modalities they felt knowledgeable about, ranging from 100% for optimizing topical glaucoma therapies to 31% for serum tears. Nearly all respondents (92%) agreed that a suggested algorithm for the treatment of OSD in glaucoma could improve their approach to management.

CONCLUSION

OSD is a common comorbidity of glaucoma. Although respondents overwhelmingly agreed that comprehensive management of OSD may lead to improved quality of life and glaucoma-related outcomes, only a small percentage felt it was presently adequately managed. Increasing knowledge related to the assessment and management of OSD in glaucoma may in the future improve patient care.

Contact Lens Wear and Dry Eye: Beyond the Known

Contact lens wear is one of the relevant risk factors for dry eye, and the coexistence of dry eye poses a serious challenge in patients wearing contact lenses. The Tear Film and Ocular Surface Society Workshop addressed issues around the topic of discomfort in contact lens wear, which is a major cause for discontinuation of contact lens wear, and termed this condition as contact lens discomfort. With the rapid advances in contact lens technology and pharmacological agents and deeper understanding of this field, updating the "new normal" beyond what is known as standard is essential. This review aims to summarize the latest topics in contact lens and dry eye that would be useful for clinicians and contact lens practitioners.

Association of Severity of Dry Eye Disease with Work Productivity and Activity Impairment in the Dry Eye Assessment and Management Study

PURPOSE

To evaluate the association of dry eye disease (DED) severity with work productivity and activity impairment.

DESIGN

Longitudinal, observational study within a randomized clinical trial.

PARTICIPANTS

People with moderate to severe DED who enrolled in the multicenter Dry Eye Assessment and Management (DREAM) study.

METHODS

Participants completed the Work Productivity and Activity Impairment questionnaire at 0, 6, and 12 months and were assessed in parallel for symptoms and signs (conjunctival and corneal staining, tear film break-up time [TBUT], and Schirmer test) of DED. Associations of work productivity and activity impairment with symptom and signs were evaluated with linear regression models using generalized estimating equations and controlling for demographics and comorbidities.

MAIN OUTCOME MEASURES

Work productivity (employment, absenteeism, presenteeism, overall work impairment) and activity impairment.

RESULTS

Among 535 participants at baseline, 279 (52%) were employed, and mean activity impairment was 24.5%. Among those employed, the mean score was 2% for absenteeism, 18% for presenteeism, and 19.6% for overall work impairment. Higher Ocular Surface Disease Index (OSDI) symptom scores were associated with greater absenteeism, presenteeism, and activity impairment. Overall work impairment and activity impairment were greater by 4.3% and 4.8%, respectively, per 10-unit difference in OSDI score (P < 0.001). Longitudinal increases (worsening) in OSDI scores were associated with increasing impairment in work and non-work-related activity: 2.0% and 3.1% per 10 units in OSDI, respectively (P < 0.01). Worse corneal staining and TBUT were associated with higher overall work impairment and activity level (P ≤ 0.04). However, longitudinal changes in these two signs were not associated with changes in work productivity or activity impairment.

CONCLUSIONS

Worse symptoms of DED are associated with decreased work productivity and activity level, both cross-sectionally (interindividually) and longitudinally within person (intraindividually). Corneal staining and TBUT are associated with interindividual differences but not intraindividual changes in work productivity and activity impairment.

A Novel Integrated Active Herbal Formulation Ameliorates Dry Eye Syndrome by Inhibiting Inflammation and Oxidative Stress and Enhancing Glycosylated Phosphoproteins in Rats

Dry eye syndrome (DES) is a chronic condition of the eye with insufficient production of tears leading to inadequate lubrication of eyes. Symptoms of DES are associated with discomfort and redness of the eye, blurred vision, and tear film instability which leads to the damaged ocular surface. Inflammation and oxidative stress play a significant role in the pathogenesis of the disease. In this study, the protective effect of different doses (100 or 200 mg/kg) of a novel multi-component oral formulation of lutein/zeaxanthin, curcumin, and vitamin D3 (LCD) was evaluated using a rat model with benzalkonium chloride (BAC)-induced dry eye syndrome. The formulation was administered orally to rats for 4 weeks. We observed a significant improvement in tear volume, tear breakup time, tear film integrity, and reduction in overall inflammation in rats fed with the LCD at dose 200 mg/kg performing better than 100 mg/kg. Furthermore, the formulation helped in lowering oxidative stress by increasing antioxidant levels and restored protective tear protein levels including MUC1, MUC4, and MUC5AC with 200 mg of LCD having the most significant effect. The results strongly suggest that the combination of lutein/zeaxanthin, curcumin, and vitamin-D3 is effective in alleviating the symptoms of dry eye condition with a multi-modal mechanism of action.

Effects of the re-esterified triglyceride (rTG) form of omega-3 supplements on dry eye following cataract surgery

Background/Aims

To evaluate the clinical outcomes of the systemic re-esterified triglyceride (rTG) form of omega-3 fatty acids in patients with dry eye symptoms after cataract surgery.

Methods

This prospective comparative cohort study comprised 66 patients complaining of new-onset non-specific typical dry eye 1 month after uncomplicated cataract surgery. Subjects were randomly allocated into control and omega-3 groups based on administration of the systemic rTG form of omega-3 fatty acids for 2 months, in addition to use of artificial teardrop. Ocular surface parameters (Schirmer’s test, tear break-up time, corneal staining score and matrix metalloproteinase-9 (MMP-9)) and subjective questionnaire results (Ocular Surface Disease Index (OSDI)) and Dry Eye Questionnaire [DEQ]) for dry eye were evaluated before and after omega-3 supplementation.

Results

Two months after omega-3 supplementation, the Oxford score was lower in the omega-3 group than in the control group. There was an improvement of subjective symptom scores of OSDI and DEQ in the omega-3 group (both p<0.05). The ratio of increasing MMP-9 level in the omega-3 group was lower than that in the control group (p=0.027).

Conclusion

The rTG form of omega-3 supplementation might be related to reduction of ocular surface inflammation rather than secretion of tears, and it might be effective for non-specific typical dry eye after uncomplicated cataract surgery.

Trial registration Number

NCT04411615.

Association of meibomian gland morphology with symptoms and signs of dry eye disease in the Dry Eye Assessment and Management (DREAM) study

PURPOSE

To describe associations between symptoms and signs of dry eye disease (DED) and meibomian gland (MG) morphology.

METHODS

Cross-sectional study utilizing data from the Dry Eye Assessment and Management (DREAM) Study. Readers graded MG features in the middle third of upper and lower lids on infrared meibography images. Associations with signs and symptoms of DED were evaluated with adjustment for age and sex.

RESULTS

Among 268 patients, no MG features were associated with symptom scores (p > 0.08). Among 394 upper eyelids, better tear break-up times (<2, >2- <3.2and ≥ 3.2 s) were associated with more tortuous glands (mean (SD) 0.58(0.95), 0.83(1.2) and 1.14 (1.4), p = 0.01) and with higher scores on a composite score of MG features (21.90 (9.76), 23.29 (9.50), 26.26 (10.27); p = 0.02). Longer Schirmer test wetting lengths (0-5, >5-10, and >10 mm) were associated with increasing composite scores (22.02 (9.29), 23.80 (10.34), 24.96 (9.96), p = 0.03). Patients with Sjogren syndrome compared to other patients had fewer distorted MGs (mean 3.4 (2.3) vs 4.3 (2.3), p = 0.03) and fewer ghost glands (mean 0.33 (0.88) vs 0.89 (1.8), p = 0.006) in the upper lid.

CONCLUSION

In the DREAM study, most MG morphologic features were not associated with the severity of DED symptoms or signs. Tortuous glands and a higher composite score for MG features were associated with longer tear break-up times and longer Schirmer test length in the upper eyelid only. Patients with Sjogren syndrome had fewer distorted and ghost glands.

Challenging and Practical Aspects of Nutrition in Chronic Graft-versus-Host Disease

There is a paucity of information about nutrition in chronic graft-versus-host disease (GVHD). The role of nutrition is important because malnutrition is strongly associated with severe chronic GVHD manifestations. There is a high prevalence of metabolic syndrome and osteoporosis in this setting. Here we review the literature, describe main aspects of nutrition and discuss macronutrients (ie, vitamins), micronutrients (ie, Mg, Zn, Ca, and K) and supplements (probiotics and omega 3 fatty acids). A search was carried out in March 2020 using PubMed. Databases were screened for searching terms in titles and abstracts referring to chronic GVHD, nutrition intervention, protein, and body composition. Data were extracted for the following outcomes: nutrition, nutrition intervention, chronic GVHD, nutrition deficiencies, diet, vitamin, dry eye, probiotic, protein, and body composition. In this report, we summarize interventional nutrition studies reported in oncology and metabolic syndrome settings and describe our nutritional clinical practice in hematopoietic cell transplantation and chronic GVHD. The impact of nutrition evaluation and intervention on muscle mass loss, dry eye, dysgeusia, metabolic syndrome, osteoporosis, and comorbidities associated with chronic GVHD need to be studied prospectively.

Clinical outcomes of ocular surface in patients treated with vitamin D oral replacement

PURPOSE

To analyze the clinical outcomes of the ocular surface in patients with vitamin D deficiency after oral replacement.

METHODS

A total of 40 patients with vitamin D deficiency were enrolled in the study. The patients received 50,000 units of oral vitamin D weekly over a period of 8 weeks. After 8 weeks, 1,500-2,000 units/d were administered for 24 weeks. Eyelid margin score, meibomian gland expressibility score, Oxford grading, Schirmer I test, tear breakup time, tear osmolarity, and the Ocular Surface Disease Index score were evaluated at baseline, and at 8, 12, and 24 weeks.

RESULTS

The meibomian gland expressibility score, Schirmer I, tear breakup time, tear osmolarity, and Ocular Surface Disease Index score showed improvement 8 weeks after vitamin D supplementation (p<0.05). Compared with the pretreatment values, the eyelid margin score and Oxford grading were decreased at week 12 (p<0.05).

CONCLUSION

Vitamin D replacement appears to improve ocular surface in individuals with vitamin D deficiency.

Efficacy of omega-3 fatty acids and punctal plugs in the prevention of isotretinoin-associated ocular surface disease

PURPOSE

To investigate the effects of omega-3 fatty acids and punctal plugs on tear film and ocular surface parameters in patients receiving systemic isotretinoin therapy.

METHODS

This is a prospective randomized study that included 180 eyes of 90 patients who had systemic isotretinoin therapy (120-150 mg/kg for at least 4-6 months). Exclusion criteria: DED according to the diagnostic criteria of TFOS DEWS II. Patients were assigned into three groups; (1) O3FAs/PPs group: A soft preloaded silicone plug was inserted in the inferior punctum of both eyes and received oral O3FAs two capsules twice daily total daily dose of 1040 mg/day for 6 months. (2) PPs group: A soft preloaded silicone plug was inserted in the inferior punctum of both eyes and received oral placebo. (3) Isotretinoin group: No intervention was done. At baseline, 1 week, 1, 3, and 6 months of study, Ocular surface evaluation tests were done in following order: OSDI, tear osmolarity, Schirmer's I test, TBUT, ocular surface staining score, and meibomian gland expression.

PRIMARY OUTCOME MEASURES

The changes in measurement of ocular surface evaluation tests including ocular surface disease index (OSDI), tear film breakup time (TFBUT), corneal staining, tear osmolarity, and meibomian gland expression at 6 months.

RESULTS

There are significant changes between all groups at 6 months follow-up. The ocular surface parameters were better for the PPs and O3FAs/PPs groups than the isotretinoin group. The isotretinoin group showed worsening of ocular surface parameters including a significant decrease of FTBUT and an increase of OSDI score, corneal staining score, tear osmolarity, and meibomian expression score. There was no significant difference in ST1 throughout the whole study in all groups. At 6 months follow-up, there were no statistically significant differences between PPs and O3FAs/PPs groups except meibomian expression score which showed a significant increase in PPs group.

CONCLUSION

Our cohort highlights the beneficial effects of the combination of O3FAs supplementation with PPs in the prevention of isotretinoin-associated OSD in this sample study.

Association of meibomian gland architecture and body mass index in a pediatric population

PURPOSE

To determine if meibomian gland architecture in a pediatric population is impacted by body mass index (BMI).

METHODS

Prospective evaluation of 175 eyes of 175 pediatric patients from two clinics. Demographic and clinical information were reviewed. Symptoms of dry eye were assessed with the Standard Patient Evaluation of Eye Dryness (SPEED) questionnaire. Meibography was performed and grading of images was performed by a masked rater using a previously validated 5-point meiboscale (0-4) for gland atrophy and a 3-point score (0-2) for gland tortuosity.

RESULTS

175 eyes of 175 participants aged 4-17 years (11.6 ± 3.7 years) were imaged. The mean meiboscore was 0.82 ± 0.94 (range 0-4) and the mean gland tortuosity score was 0.53 ± 0.70 (range 0-2). Ninety-six patients (56%) showed evidence of gland atrophy (meiboscore greater than 0) and the majority of patients (n=50, 29%) had a gland tortuosity score of 1. The mean BMI was 20.5 ± 4.86 kg/m² with 39.4% of patients (n = 69) above the 85th percentile. BMI percentile was not found to be a significant predictor of a meiboscore greater than 0 (odds ratio (OR) 1.004 95% confidence interval (CI) (0.99-1.10, p = 0.41). However, BMI percentile was found to be a significant predictor of gland tortuosity score (OR 1.01 95% CI (1.00-1.02), p = 0.02). Patients with BMI percentiles between 41 and 60 were 3.79 times more likely to have a gland tortuosity score of greater than 0 than patients with BMI percentiles between 0 and 20 (OR 3.789 CI (1.17-12.24)). No significant associations were found between age, race, or sex and meiboscore or tortuosity. There was a trend towards reduction in lipid layer thickness with increasing BMI percentile (p = 0.028, r² = 0.04).

CONCLUSION

In this pediatric population, there was an association between meibomian gland tortuosity and higher percentiles of BMI. Future studies are needed to elucidate the pathogenesis of meibomian gland tortuosity and atrophy in pediatric patients.

Current State of Knowledge on Primary Sjögren's Syndrome, an Autoimmune Exocrinopathy

Primary Sjögren's syndrome (pSS) is a chronic systemic autoimmune rheumatic disease characterized by lymphoplasmacytic infiltration of the salivary and lacrimal glands, whereby sicca syndrome and/or systemic manifestations are the clinical hallmarks, associated with a particular autoantibody profile. pSS is the most frequent connective tissue disease after rheumatoid arthritis, affecting 0.3-3% of the population. Women are more prone to develop pSS than men, with a sex ratio of 9:1. Considered in the past as innocent collateral passive victims of autoimmunity, the epithelial cells of the salivary glands are now known to play an active role in the pathogenesis of the disease. The aetiology of the "autoimmune epithelitis" still remains unknown, but certainly involves genetic, environmental and hormonal factors. Later during the disease evolution, the subsequent chronic activation of B cells can lead to the development of systemic manifestations or non-Hodgkin's lymphoma. The aim of the present comprehensive review is to provide the current state of knowledge on pSS. The review addresses the clinical manifestations and complications of the disease, the diagnostic workup, the pathogenic mechanisms and the therapeutic approaches.

The role of Th17 immunity in chronic ocular surface disorders

Th17 cells have been implicated in the pathogenesis of numerous inflammatory and autoimmune conditions. At the ocular surface, Th17 cells have been identified as key effector cells in chronic ocular surface disease. Evidence from murine studies indicates that following differentiation and expansion, Th17 cells migrate from the lymphoid tissues to the eye, where they release inflammatory cytokines including, but not limited to, their hallmark cytokine IL-17A. As the acute phase subsides, a population of long-lived memory Th17 cells persist, which predispose hosts both to chronic inflammation and severe exacerbations of disease; of great interest is the small subset of Th17/1 cells that secrete both IL-17A and IFN-γ in acute-on-chronic disease exacerbation. Over the past decade, substantial progress has been made in deciphering how Th17 cells interact with the immune and neuroimmune pathways that mediate chronic ocular surface disease. Here, we review (i) the evidence for Th17 immunity in chronic ocular surface disease, (ii) regulatory mechanisms that constrain the Th17 immune response, and (iii) novel therapeutic strategies targeting Th17 cells.

Climatic and Environmental Correlates of Dry Eye Disease Severity: A Report From the Dry Eye Assessment and Management (DREAM) Study

Purpose

Correlate climate, weather parameters, and environmental exposures with the severity of symptoms and signs of dry eye disease (DED) in Dry Eye Assessment and Management (DREAM) study participants.

Methods

Participants from five distinct climates completed the Ocular Surface Disease Index (OSDI) and were examined for corneal and conjunctival staining, tear breakup time (TBUT), and Schirmer's testing at baseline, 3, 6, and 12 months. Climate, weather parameters, and pollutants including ozone (O₃), carbon monoxide (CO), nitrous oxides (NO₂, NO_x, NO_y), sulfur dioxide (SO₂), particulate matter, and optical depth were obtained from governmental databases. Multivariate analysis and partial correlation coefficients (ρ) were used to assess associations, adjusted for age, sex, and the presence of Sjögren disease.

Results

Among 535 participants, 81% were female and mean age was 58 years. Participants from the Mediterranean climate demonstrated better corneal fluorescein staining, better TBUT, and higher Schirmer's test scores throughout the calendar year (each P < 0.0001). Greater corneal fluorescein staining was associated with lower humidity (P < 0.0038). TBUT measurements positively correlated with temperature, humidity, and dewpoint and inversely correlated with NO₂ levels (P < 0.0038). Paradoxically, some airborne pollutants were associated with less severe signs of dry eye (P < 0.0038). Windspeed was not correlated with signs of DED, and OSDI scores did not correlate with individual environmental exposures.

Conclusions

Dry eye signs differed between climates and local humidity levels. With the exception of NO₂, airborne pollutants were not associated with detrimental dry eye features.

Translational Relevance

These results support limiting dry air exposure for patients with DED.

Omega-3 Fatty Acids and Eye Health: Opinions and Self-Reported Practice Behaviors of Optometrists in Australia and New Zealand

This study investigated optometrists’ attitudes and self-reported practice behaviors towards omega-3 fatty acids for eye health, and knowledge and understanding of their potential risks and benefits. An anonymous online survey was distributed to optometrists in Australia and New Zealand. Questions included practitioner demographics and practice modality; self-reported practices and recommendations relating to diet, nutritional supplements, and omega-3 fatty acids for age-related macular degeneration (AMD) and dry eye disease (DED); and practitioner knowledge about omega-3 fatty acids. Of 206 included surveys, most respondents (79%) indicated recommending for their patients to consume omega-3 fatty acids to improve their eye health. Sixty-eight percent of respondents indicated recommending omega-3-rich foods for AMD management, while 62% indicated recommending omega-3 supplements. Most respondents (78%) indicated recommending omega-3-rich foods or supplements for DED. For DED, recommended omega-3 supplement dosages were (median [inter-quartile range, IQR]) 2000 mg [1000–2750 mg] per day. The main sources of information reported by respondents to guide their clinical decision making were continuing education articles and conferences. In conclusion, optometrists routinely make clinical recommendations about diet and omega-3 fatty acids. Future education could target improving optometrists’ knowledge of differences in the evidence for whole-food versus supplement sources of omega-3 fatty acids in AMD. Further research is needed to address uncertainties in the evidence regarding optimal omega-3 dosage and formulation composition in DED.

Climatic and Environmental Correlates of Dry Eye Disease Severity: A Report From the Dry Eye Assessment and Management (DREAM) Study

PURPOSE

Correlate climate, weather parameters, and environmental exposures with the severity of symptoms and signs of dry eye disease (DED) in Dry Eye Assessment and Management (DREAM) study participants.

METHODS

Participants from five distinct climates completed the Ocular Surface Disease Index (OSDI) and were examined for corneal and conjunctival staining, tear breakup time (TBUT), and Schirmer's testing at baseline, 3, 6, and 12 months. Climate, weather parameters, and pollutants including ozone (O₃), carbon monoxide (CO), nitrous oxides (NO₂, NO_x, NO_y), sulfur dioxide (SO₂), particulate matter, and optical depth were obtained from governmental databases. Multivariate analysis and partial correlation coefficients (ρ) were used to assess associations, adjusted for age, sex, and the presence of Sjögren disease.

RESULTS

Among 535 participants, 81% were female and mean age was 58 years. Participants from the Mediterranean climate demonstrated better corneal fluorescein staining, better TBUT, and higher Schirmer's test scores throughout the calendar year (each P < 0.0001). Greater corneal fluorescein staining was associated with lower humidity (P < 0.0038). TBUT measurements positively correlated with temperature, humidity, and dewpoint and inversely correlated with NO₂ levels (P < 0.0038). Paradoxically, some airborne pollutants were associated with less severe signs of dry eye (P < 0.0038). Windspeed was not correlated with signs of DED, and OSDI scores did not correlate with individual environmental exposures.

CONCLUSIONS

Dry eye signs differed between climates and local humidity levels. With the exception of NO₂, airborne pollutants were not associated with detrimental dry eye features.

TRANSLATIONAL RELEVANCE

These results support limiting dry air exposure for patients with DED.

The Role of Nutrition and Nutritional Supplements in Ocular Surface Diseases

Dry eye disease (DED) is a multifactorial disease of the ocular surface system whose chore mechanisms are tear film instability, inflammation, tear hyperosmolarity and epithelial damage. In recent years, novel therapies specifically targeting inflammation and oxidative stress are being investigated and used in this field. Therefore, an increasing body of evidence supporting the possible role of different micronutrients and nutraceutical products for the treatment of ocular surface diseases is now available. In the present review, we analyzed in detail the effects on ocular surface of omega-3 fatty acids, vitamins A, B12, C, D, selenium, curcumin and flavonoids. Among these, the efficacy of omega-3 fatty acid supplementation in ameliorating DED signs and symptoms is supported by robust scientific evidence. Further long-term clinical trials are warranted to confirm the safety and efficacy of the supplementation of the other micronutrients and nutraceuticals.

Omega-3 fatty acids for the primary and secondary prevention of cardiovascular disease

BACKGROUND

Omega-3 polyunsaturated fatty acids from oily fish (long-chain omega-3 (LCn3)), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA)), as well as from plants (alpha-linolenic acid (ALA)) may benefit cardiovascular health. Guidelines recommend increasing omega-3-rich foods, and sometimes supplementation, but recent trials have not confirmed this.

OBJECTIVES

To assess the effects of increased intake of fish- and plant-based omega-3 fats for all-cause mortality, cardiovascular events, adiposity and lipids.

SEARCH METHODS

We searched CENTRAL, MEDLINE and Embase to February 2019, plus ClinicalTrials.gov and World Health Organization International Clinical Trials Registry to August 2019, with no language restrictions. We handsearched systematic review references and bibliographies and contacted trial authors.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) that lasted at least 12 months and compared supplementation or advice to increase LCn3 or ALA intake, or both, versus usual or lower intake.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion, extracted data and assessed validity. We performed separate random-effects meta-analysis for ALA and LCn3 interventions, and assessed dose-response relationships through meta-regression.

MAIN RESULTS

We included 86 RCTs (162,796 participants) in this review update and found that 28 were at low summary risk of bias. Trials were of 12 to 88 months' duration and included adults at varying cardiovascular risk, mainly in high-income countries. Most trials assessed LCn3 supplementation with capsules, but some used LCn3- or ALA-rich or enriched foods or dietary advice compared to placebo or usual diet. LCn3 doses ranged from 0.5 g a day to more than 5 g a day (19 RCTs gave at least 3 g LCn3 daily). Meta-analysis and sensitivity analyses suggested little or no effect of increasing LCn3 on all-cause mortality (risk ratio (RR) 0.97, 95% confidence interval (CI) 0.93 to 1.01; 143,693 participants; 11,297 deaths in 45 RCTs; high-certainty evidence), cardiovascular mortality (RR 0.92, 95% CI 0.86 to 0.99; 117,837 participants; 5658 deaths in 29 RCTs; moderate-certainty evidence), cardiovascular events (RR 0.96, 95% CI 0.92 to 1.01; 140,482 participants; 17,619 people experienced events in 43 RCTs; high-certainty evidence), stroke (RR 1.02, 95% CI 0.94 to 1.12; 138,888 participants; 2850 strokes in 31 RCTs; moderate-certainty evidence) or arrhythmia (RR 0.99, 95% CI 0.92 to 1.06; 77,990 participants; 4586 people experienced arrhythmia in 30 RCTs; low-certainty evidence). Increasing LCn3 may slightly reduce coronary heart disease mortality (number needed to treat for an additional beneficial outcome (NNTB) 334, RR 0.90, 95% CI 0.81 to 1.00; 127,378 participants; 3598 coronary heart disease deaths in 24 RCTs, low-certainty evidence) and coronary heart disease events (NNTB 167, RR 0.91, 95% CI 0.85 to 0.97; 134,116 participants; 8791 people experienced coronary heart disease events in 32 RCTs, low-certainty evidence). Overall, effects did not differ by trial duration or LCn3 dose in pre-planned subgrouping or meta-regression. There is little evidence of effects of eating fish. Increasing ALA intake probably makes little or no difference to all-cause mortality (RR 1.01, 95% CI 0.84 to 1.20; 19,327 participants; 459 deaths in 5 RCTs, moderate-certainty evidence),cardiovascular mortality (RR 0.96, 95% CI 0.74 to 1.25; 18,619 participants; 219 cardiovascular deaths in 4 RCTs; moderate-certainty evidence), coronary heart disease mortality (RR 0.95, 95% CI 0.72 to 1.26; 18,353 participants; 193 coronary heart disease deaths in 3 RCTs; moderate-certainty evidence) and coronary heart disease events (RR 1.00, 95% CI 0.82 to 1.22; 19,061 participants; 397 coronary heart disease events in 4 RCTs; low-certainty evidence). However, increased ALA may slightly reduce risk of cardiovascular disease events (NNTB 500, RR 0.95, 95% CI 0.83 to 1.07; but RR 0.91, 95% CI 0.79 to 1.04 in RCTs at low summary risk of bias; 19,327 participants; 884 cardiovascular disease events in 5 RCTs; low-certainty evidence), and probably slightly reduces risk of arrhythmia (NNTB 91, RR 0.73, 95% CI 0.55 to 0.97; 4912 participants; 173 events in 2 RCTs; moderate-certainty evidence). Effects on stroke are unclear. Increasing LCn3 and ALA had little or no effect on serious adverse events, adiposity, lipids and blood pressure, except increasing LCn3 reduced triglycerides by ˜15% in a dose-dependent way (high-certainty evidence).

AUTHORS' CONCLUSIONS

This is the most extensive systematic assessment of effects of omega-3 fats on cardiovascular health to date. Moderate- and low-certainty evidence suggests that increasing LCn3 slightly reduces risk of coronary heart disease mortality and events, and reduces serum triglycerides (evidence mainly from supplement trials). Increasing ALA slightly reduces risk of cardiovascular events and arrhythmia.

Explanatory Model of Dry Eye Disease Using Health and Nutrition Examinations: Machine Learning and Network-Based Factor Analysis From a National Survey

BACKGROUND

Dry eye disease (DED) is a complex disease of the ocular surface, and its associated factors are important for understanding and effectively treating DED.

OBJECTIVE

This study aimed to provide an integrative and personalized model of DED by making an explanatory model of DED using as many factors as possible from the Korea National Health and Nutrition Examination Survey (KNHANES) data.

METHODS

Using KNHANES data for 2012 (4391 sample cases), a point-based scoring system was created for ranking factors associated with DED and assessing patient-specific DED risk. First, decision trees and lasso were used to classify continuous factors and to select important factors, respectively. Next, a survey-weighted multiple logistic regression was trained using these factors, and points were assigned using the regression coefficients. Finally, network graphs of partial correlations between factors were utilized to study the interrelatedness of DED-associated factors.

RESULTS

The point-based model achieved an area under the curve of 0.70 (95% CI 0.61-0.78), and 13 of 78 factors considered were chosen. Important factors included sex (+9 points for women), corneal refractive surgery (+9 points), current depression (+7 points), cataract surgery (+7 points), stress (+6 points), age (54-66 years; +4 points), rhinitis (+4 points), lipid-lowering medication (+4 points), and intake of omega-3 (0.43%-0.65% kcal/day; -4 points). Among these, the age group 54 to 66 years had high centrality in the network, whereas omega-3 had low centrality.

CONCLUSIONS

Integrative understanding of DED was possible using the machine learning-based model and network-based factor analysis. This method for finding important risk factors and identifying patient-specific risk could be applied to other multifactorial diseases.

Comparison of the iLUX and the LipiFlow for the Treatment of Meibomian Gland Dysfunction and Symptoms: A Randomized Clinical Trial

Purpose

To compare the effects of eyelid treatment with the iLUX MGD Treatment System and the LipiFlow Thermal Pulsation System on objective and subjective parameters of meibomian gland function and symptoms.

Patients and Methods

In this randomized, open-label, controlled, multicenter clinical trial, both eyes of 142 patients aged ≥18 years with Ocular Surface Disease Index (OSDI) scores ≥23, total meibomian gland scores (MGS) ≤12 in the lower eyelid of each eye, and tear break-up time (TBUT) <10 s were randomized 1:1 to iLUX or LipiFlow treatment, with stratification by test center. The primary effectiveness endpoints were changes in total MGS (masked) and TBUT from baseline to 4 weeks. The secondary effectiveness endpoint was changed in OSDI score from baseline to 4 weeks.

Results

Both devices significantly improved effectiveness outcomes, with no differences between the two devices. At the 4-week visit, mean MGS, TBUT, and OSDI scores improved at least 16.9 ± 11.5, 2.6 ± 3.2 s, and 28.0 ± 22.8, respectively, across treatment groups and treated eyes. Four device/procedure-related events occurred in the iLUX group, compared with none in the LipiFlow group, but there were no device-related adverse events that involved changes in lid margins, eyelids, or lash integrity. Corneal staining, intraocular pressure, and visual acuity did not differ in the two groups.

Conclusion

Both treatments produced significant improvements in meibomian gland function and symptoms. For all effectiveness measures, there were no statistically significant differences between the two treatments.

Impact of Dry Eye on Visual Acuity and Contrast Sensitivity: Dry Eye Assessment and Management Study

SIGNIFICANCE

Identification of the association of specific signs of dry eye disease with specific visual function deficits may allow for more targeted approaches to treatment.

PURPOSE

The purpose of this study was to explore the association of dry eye signs and symptoms with visual acuity (VA) and contrast sensitivity in the Dry Eye Assessment and Management study.

METHODS

Baseline data from participants in the Dry Eye Assessment and Management study were used in this secondary cross-sectional analysis. Standardized procedures were used to obtain results on the Ocular Surface Disease Index (OSDI), high-contrast logMAR VA, contrast sensitivity, tear film debris, tear breakup time (TBUT), corneal fluorescein staining, meibomian gland evaluation, conjunctival lissamine green staining, and Schirmer test scores. Generalized linear models that included age, refractive error status, and cataract status were used to assess the association between VA and contrast sensitivity with OSDI score and each dry eye sign. The Hochberg procedure was used to account for multiple comparisons.

RESULTS

Among 487 participants (974 eyes), worse VA was associated with worse mean score on the OSDI vision subscale (39.4 for VA 20/32 or worse vs. 32.4 for VA 20/16 or better; adjusted linear trend, P = .02); scores were not associated with contrast sensitivity. Severe meibomian gland plugging and abnormal secretions were associated with worse mean log contrast sensitivity (1.48 for severe vs. 1.54 for not plugged [P = .04] and 1.49 for obstructed vs. 1.57 for clear [P = .002], respectively). Longer TBUT was associated with better mean log contrast sensitivity (1.57 for TBUT >5 seconds and 1.51 for TBUT ≤2 seconds, P < .0001).

CONCLUSIONS

Worse VA rather than worse contrast sensitivity drives vision-related symptoms in dry eye. Greater tear film instability was associated with worse contrast sensitivity.

Advances in the diagnosis and treatment of dry eye

The core mechanism of dry eye is the tear film instability. Tear film-oriented diagnosis (TFOD) is a concept to clarify the cause of tear film instability by tear film, and tear film-oriented treatment (TFOT) is a concept to treat dry eye disease by replacing the lacking components of the tear film layer based on the TFOD. In TFOD, the fluorescein breakup pattern of the tear film is important, and the subtype of dry eye can be judged to some extent from the breakup patterns. Current noninvasive devices related to the dynamic analysis of the tear film and visual acuity enabled the diagnosis of dry eye, subtype analysis, and the extent of severity. In Asian countries, secretagogues represent the main treatment in TFOT. Since meibomian gland dysfunction is a factor that greatly affects the tear breakup time, its treatment is also essential in the dry eye treatment strategy. A newly discovered dry eye subtype is the short breakup time-type (BUT) of dry eye. The only abnormal finding in this disease is the short BUT, suggesting a relationship with ocular neuropathic pain and eye strain. Recently, data from many studies have accumulated which show that dry eye is a life-style disease. In addition to the treatment of dry eyes, it is becoming possible to prevent the onset by intervening with the daily habits, diet, exercise and sleep, etc. It has been pointed out that oxidative stress is also involved in the pathology of dry eye, and intervention is being carried out by improving diet and taking supplements. Future research will be needed to link clinical findings to the molecular biological findings in the tear film.

Toward better outcomes in Sjögren's syndrome: The promise of a stratified medicine approach

Sjögren's syndrome is a systemic autoimmune disease defined by its targeted inflammation of the salivary and lacrimal glands, resulting in dry mouth and eyes in the majority and persistent or recurrent salivary gland enlargement in a minority of those affected. Involvement of major organs, an increased risk of lymphoma, and autoantibodies against ubiquitous cellular ribonucleoproteins define some of its systemic features. Those affected have a high symptom burden and the development of disease-modifying therapies is thus an urgent need. A stratified medicine approach offers promise as a means of targeting specific therapies to patients for whom the mechanism of action is most relevant. Implementation of this approach will require an understanding of the pathophysiological processes underlying different patient subsets, and then identifying or developing a drug that targets this pathway. Such therapies would be most effective if implemented early in the disease course before the advent of adverse outcomes or glandular damage. This review will provide a disease overview followed by an analysis of the feasibility of a stratified medicine approach, focusing on the disease heterogeneity, predictors of disease progression and adverse outcomes, and recent advances in the development of relevant outcome measures and new therapies.

Managing Dry Eye Disease and Facilitating Realistic Patient Expectations: A Review and Appraisal of Current Therapies

Dry eye disease (DED) is a multifactorial disease of the ocular surface characterized by loss of homeostasis of the tear film and accompanied by ocular signs and symptoms such as corneal and conjunctival damage, patient discomfort, and visual disturbance. The prevalence of DED ranges from 5%−33%. Patients with DED may have a reduced quality of life due to their discomfort and visual disturbances. The multifactorial nature of DED requires a multi-targeted treatment approach to address the signs and symptoms. Treatment for DED should follow a step-wise approach beginning with education, dietary modification, and lid and lash hygiene, and progressing to pharmacologic and nonpharmacologic interventions. Ocular lubricants, a mainstay of DED therapy, provide temporary symptomatic relief for the patient, but do not address the underlying pathophysiology. Some currently available pharmacologic treatments that address the underlying pathophysiology of DED may have a delay of 3−6 months in the onset of therapeutic effect; however, these treatment options may also have tolerability issues. These challenges highlight the need for newer pharmacologic treatments with an earlier onset of observable clinical effect and the potential for improved tolerability profile. Patient education is vital to DED management and should convey the complex and chronic nature of DED. It is important for the eye care practitioner to set realistic expectations with the patient when managing DED to help improve treatment success. This helps the patient understand the need for ongoing treatment and that results will likely not be seen immediately. This review covers the current management of DED, focusing on pharmacologic management, and offers recommendations for the practitioner to help facilitate realistic patient expectations for the treatment of DED.

Changes in Tear Lipid Layer Thickness and Symptoms Following the Use of Artificial Tears with and Without Omega-3 Fatty Acids: A Randomized, Double-Masked, Crossover Study

Purpose

To determine if an eye drop containing omega-3 fatty acids (Refresh Optive MEGA-3^®, Allergan plc, Dublin, Ireland) increases the lipid layer thickness (LLT) of the tear film versus a non-emollient eye drop (Refresh Optive, Allergan plc).

Methods

Patients (≥30 years) with baseline LLT ≤75 nm completed the Current Symptoms Survey (CSS – a visual analog survey of dry eye symptoms), and LLT was measured pre- and post-instillation (15 and 60 mins) of their randomly assigned treatment. After washout, patients were tested with the other treatment. Primary endpoint: change in LLT from baseline. Secondary endpoint: CSS results.

Results

Of 21 patients enrolled, 19 completed the study. With the omega-3–containing eye drop, the mean (standard deviation) LLT increase from baseline at 15 mins was statistically significant in the overall field (8.8 [11.5] nm; P<0.001), and in each individual zone (superior, central, and inferior). At 1 hr, the LLT change from baseline was statistically significant overall (4.4 [9.7] nm; P<0.02) and in the inferior and central zones. With the aqueous eye drop, LLT change from baseline was only significant at 15 mins in the inferior field. The CSS analysis revealed a ≥8.68-unit decrease in mean average dryness score from baseline at 15 and 60 mins post-instillation of the lipid-based treatment (P≤0.03).

Conclusion

The eye drop containing omega-3 fatty acids increased LLT at 15 mins, maintaining it at 1 hr post-instillation. Dryness symptoms also improved and maintained improved levels 1 hr after instillation, indicating that the product may benefit symptomatic patients with evaporative dry eye.

Omega-3 and omega-6 polyunsaturated fatty acids for dry eye disease

BACKGROUND

Polyunsaturated fatty acid (PUFA) supplements, involving omega-3 and/or omega-6 components, have been proposed as a therapy for dry eye. Omega-3 PUFAs exist in both short- (alpha-linolenic acid [ALA]) and long-chain (eicosapentaenoic acid [EPA] and docosahexaenoic acid [DHA]) forms, which largely derive from certain plant- and marine-based foods respectively. Omega-6 PUFAs are present in some vegetable oils, meats, and other animal products.

OBJECTIVES

To assess the effects of omega-3 and omega-6 polyunsaturated fatty acid (PUFA) supplements on dry eye signs and symptoms.

SEARCH METHODS

CENTRAL, Medline, Embase, two other databases and three trial registries were searched in February 2018, together with reference checking. A top-up search was conducted in October 2019, but the results have not yet been incorporated.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) involving dry eye participants, in which omega-3 and/or omega-6 supplements were compared with a placebo/control supplement, artificial tears, or no treatment. We included head-to-head trials comparing different forms or doses of PUFAs.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods and assessed the certainty of the evidence using GRADE.

MAIN RESULTS

We included 34 RCTs, involving 4314 adult participants from 13 countries with dry eye of variable severity and etiology. Follow-up ranged from one to 12 months. Nine (26.5%) studies had published protocols and/or were registered. Over half of studies had high risk of bias in one or more domains. Long-chain omega-3 (EPA and DHA) versus placebo or no treatment (10 RCTs) We found low certainty evidence that there may be little to no reduction in dry eye symptoms with long-chain omega-3 versus placebo (four studies, 677 participants; mean difference [MD] -2.47, 95% confidence interval [CI] -5.14 to 0.19 units). We found moderate certainty evidence for a probable benefit of long-chain omega-3 supplements in increasing aqueous tear production relative to placebo (six studies, 1704 participants; MD 0.68, 95% CI 0.26 to 1.09 mm/5 min using the Schirmer test), although we did not judge this difference to be clinically meaningful. We found low certainty evidence for a possible reduction in tear osmolarity (one study, 54 participants; MD -17.71, 95% CI -28.07 to -7.35 mOsmol/L). Heterogeneity was too substantial to pool data on tear break-up time (TBUT) and adverse effects. Combined omega-3 and omega-6 versus placebo (four RCTs) For symptoms (low certainty) and ocular surface staining (moderate certainty), data from the four included trials could not be meta-analyzed, and thus effects on these outcomes were unclear. For the Schirmer test, we found moderate certainty evidence that there was no intergroup difference (four studies, 455 participants; MD: 0.66, 95% CI -0.45 to 1.77 mm/5 min). There was moderate certainty for a probable improvement in TBUT with the PUFA intervention relative to placebo (four studies, 455 participants; MD 0.55, 95% CI 0.04 to 1.07 seconds). Effects on tear osmolarity and adverse events were unclear, with data only available from a single small study for each outcome. Omega-3 plus conventional therapy versus conventional therapy alone (two RCTs) For omega-3 plus conventional therapy versus conventional therapy alone, we found low certainty evidence suggesting an intergroup difference in symptoms favoring the omega-3 group (two studies, 70 participants; MD -7.16, 95% CI -13.97 to -0.34 OSDI units). Data could not be combined for all other outcomes. Long-chain omega-3 (EPA and DHA) versus omega-6 (five RCTs) For long-chain omega-3 versus omega-6 supplementation, we found moderate certainty evidence for a probable improvement in dry eye symptoms (two studies, 130 participants; MD -11.88, 95% CI -18.85 to -4.92 OSDI units). Meta-analysis was not possible for outcomes relating to ocular surface staining, Schirmer test or TBUT. We found low certainty evidence for a potential improvement in tear osmolarity (one study, 105 participants; MD -11.10, 95% CI -12.15 to -10.05 mOsmol/L). There was low level certainty regarding any potential effect on gastrointestinal side effects (two studies, 91 participants; RR 2.34, 95% CI 0.35 to 15.54).

AUTHORS' CONCLUSIONS

Overall, the findings in this review suggest a possible role for long-chain omega-3 supplementation in managing dry eye disease, although the evidence is uncertain and inconsistent. A core outcome set would work toward improving the consistency of reporting and the capacity to synthesize evidence.

Enriched Marine Oil Supplements Increase Peripheral Blood Specialized Pro-Resolving Mediators Concentrations and Reprogram Host Immune Responses: A Randomized Double-Blind Placebo-Controlled Study

RATIONALE

Specialized pro-resolving mediators (SPM-lipoxins, resolvins, protectins, and maresins) are produced via the enzymatic conversion of essential fatty acids, including the omega-3 fatty acids docosahexaenoic acid and n-3 docosapentaenoic acid. These mediators exert potent leukocyte directed actions and control vascular inflammation. Supplementation of animals and humans with essential fatty acids, in particular omega-3 fatty acids, exerts protective actions reducing vascular and systemic inflammation. Of note, the mechanism(s) activated by these supplements in exerting their protective actions remain poorly understood.

OBJECTIVE

Given that essential fatty acids are precursors in the biosynthesises of SPM, the aim of the present study was to establish the relationship between supplementation and peripheral SPM concentrations. We also investigated the relationship between changes in plasma SPM concentrations and peripheral blood platelet and leukocyte responses.

METHODS AND RESULTS

Healthy volunteers were enrolled in a double-blinded, placebo-controlled, crossover study, and peripheral blood was collected at baseline, 2, 4, 6, and 24 hours post administration of placebo or one of 3 doses of an enriched marine oil supplement. Assessment of plasma SPM concentrations using lipid mediator profiling demonstrated a time- and dose-dependent increase in peripheral blood SPM concentration. Supplementation also led to a regulation of peripheral blood cell responses. Here we found a dose-dependent increase in neutrophil and monocyte phagocytosis of bacteria and a decrease in the diurnal activation of leukocytes and platelets, as measured by a reduction in adhesion molecule expression. In addition, transcriptomic analysis of peripheral blood cells demonstrated a marked change in transcript levels of immune and metabolic genes 24 hours post supplementation when compared with placebo.

CONCLUSIONS

Together, these findings demonstrate that supplementation with an enriched marine oil leads to an increase in peripheral blood SPM concentrations and reprograms peripheral blood cells, indicating a role for SPM in mediating the immune-directed actions of this supplement.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT03347006.

An artificial tear containing flaxseed oil for treating dry eye disease: A randomized controlled trial

PURPOSE

To evaluate the efficacy and safety of a nano-emulsion artificial tear (OM3) containing carboxymethylcellulose (CMC) and glycerin, flaxseed oil and castor oil, and three osmoprotectants (levocarnitine, erythritol, and trehalose) compared with an artificial tear (Refresh Optive Advanced [ROA]) containing the same ingredients with the exception of trehalose and flaxseed oil.

METHODS

In this multicenter, double-masked, randomized, two-arm, parallel-group, 6-visit study (screening, baseline, and days 7, 30, 60, and 90), subjects with dry eye disease underwent an open-label, 7-day run-in with CMC 0.5% (Refresh Plus), before 1:1 randomization to OM3 or ROA for 90 days (both instilled ≥2 daily). Ocular Surface Disease Index (OSDI; primary endpoint change from baseline at day 90), tear film breakup time (TBUT), and ocular staining (combined/corneal/conjunctival) were assessed; change from baseline in these parameters was calculated at each timepoint. Treatment-related adverse events (AEs) were assessed at each visit.

RESULTS

Overall, 242 subjects were randomized (OM3, n = 120; ROA, n = 122). At day 90, significant improvements in OSDI, ocular staining and TBUT were evident in both treatment groups. Significant (P < 0.05) between-group differences in favor of OM3 were observed for combined ocular staining (all timepoints), corneal staining (day 90), and conjunctival staining (day 30). Treatment-related AEs were higher in the ROA (9.8%) versus OM3 (6.7%) group; blurred vision was among the most commonly reported AE (OM3 0% vs ROA 4.1%).

CONCLUSION

These findings support the application of OM3, a novel preservative-free, nano-emulsion tear formulation with trehalose and flaxseed oil, for the treatment of dry eye disease.

Evaluation of use of essential fatty acids in topical ophthalmic preparations for dry eye

PURPOSE

Essential fatty acids (EFAs) as dietary supplements are used in treating dry-eye for reducing inflammation at the ocular surface. Their topical application in eye drops to deliver fatty acid (FA) directly to the ocular surface requires thorough investigation. Being lipids in nature EFAs can interact with tear lipids and affect tear stability. This study aimed at investigating the biophysical interactions of EFAs with Meibomian lipids.

METHODS

Rheology of mixtures of Human Meibomian lipids with EFAs (LA-linoleic acid, ALA-alpha-linolenic acid), OA (oleic acid), and GLA (gamma-linolenic acid) was studied using Langmuir trough technology on an artificial tear solution at the ocular surface temperature. Pressure-area profiles were used to determine compressibility and elasticity of the mixed films.

RESULTS

LA enhanced spreading of Meibomian lipids and increased their compressibility and elasticity which can be beneficial for tear stability. ALA condensed Meibomian lipids film with less elasticity deemed unfavourable for tear stability. OA expanded Meibomian lipids but decreased elasticity at high compressions making films less stable. GLA had little or no favourable effect on tear stability. Higher concentrations of FAs made films less stable.

CONCLUSIONS

EFAs or OA in topical ophthalmic preparations can affect spread and stability of the tear film lipid layer. Rheology of mixed films should be tested using Langmuir trough technology to determine suitable type and amount of a lipid additive for therapeutic eye drops. In topical applications, the omega-6 LA (not omega-3 FA) at low concentrations (20 mol%) can be beneficial for enhancing tear stability in dry eye patients.

Efficacy of topical microemulsion of fatty acids of the ω-3 series on the sub-epithelial corneal nerves regeneration after epithelium-off corneal collagen cross-linking for keratoconus

PURPOSE

To evaluate efficacy of a microemulsion of fatty acids of the ω-3 series on the regeneration of the sub-epithelial corneal nerve plexus in patients with keratoconus after epi-off cross-linking.

METHODS

In this prospective study, we recruited 40 patients, 18 females, mean age 28 years (range 22-37), who were randomly divided in two groups. Group A, 20 patients, after cross-linking were treated with a microemulsion of fatty acids of the ω-3 series. Group B were treated with hyaluronic acid (0.15%)-based tear substitute. Nerve tortuosity, reflectivity and density were examined with in vivo confocal microscopy. Ocular surface disease index (OSDI) questionnaire at the preoperative and at each follow-up visit (1, 3 and 6 months) after treatment was completed.

RESULTS

No significant difference between the two groups was noted at 1 month in terms of nerve density and OSDI. A statistically significant difference between the two groups was detected at 3 months in terms of nerve fibers density (6 ± 0.82 in Group A and 1 ± 0.51 in Group B, P = 0.0001). Reflectivity and tortuosity of the fibers did not show significant differences between the two groups at any time point. At 1 month, OSDI average value in group A and in group B was 31.5 ± 1.94 and 30 ± 1.96, at 3 months 13 ± 1.71 and 28 ± 1.83, and at 6 months 10.5 ± 1.87 and 9.0 ± 1.81, respectively.

CONCLUSION

The use of a microemulsion of fatty acids appears to ensure a faster regeneration of nerve fibers in patients undergoing epi-off cross-linking.