A randomized controlled trial of omega-3 fatty acids in dry eye syndrome

Harnessing nutrients and natural products for sustainable drug development against aging

Developing treatments for age-related diseases requires cost-effective and efficient approaches. Nutrients and natural metabolites offer safer alternatives to synthetic drugs. Aging increases the need for solutions that protect health and repair cells. Recent studies show that nutrients and natural products reduce oxidative stress, regulate metabolism, and influence longevity-related genes. This review focuses on vitamins, minerals, antioxidants, and natural products that improve healthspan and combat aging. It also discusses challenges such as standardization, clinical validation, and regulatory approval. Finally, emerging trends, such as personalized nutrition and advanced delivery systems, highlight the potential of these metabolites for addressing aging.

The role of vitamins and nutrients in rosacea

Rosacea is a common inflammatory skin condition displaying symptoms like flushing, erythema, papules, and pustules. Oral antibiotics, despite long-term adverse effects, are often used due to topical treatment limitations, underscoring the need for cost-effective choices like dietary modifications. Our review investigates the role of vitamins and minerals in rosacea, and provides evidence-based recommendations for supplementation and topical treatment of these nutrients for rosacea. An online search was performed on PubMed, Web of Science, Science Direct, Google Scholar, and ClinicalTrials.gov from 1998 to 2023. Included studies were summarized and assessed for quality and relevance in rosacea management. Varied outcomes emerged concerning the impact of essential vitamins and minerals on rosacea treatment. Vitamin A derivatives, specifically oral isotretinoin, demonstrated significant efficacy, with a 90% reduction in lesions, complete remission in 24% of patients, and marked improvement in 57% of patients. Vitamin B3 derivatives, such as topical 1-methylnicotinamide 0.25% and NADH 1%, improved symptoms in 76.4% (26/34) and 80% of patients, respectively. Outcomes for vitamin D, vitamin C, and zinc supplementation varied across studies. However, zinc sulfate solution 5% significantly reduced acne rosacea severity for patients with 40% and 60% exhibiting a moderate or good response, respectively. Omega-3 fatty acids showed significant improvement in alleviating xerophthalmia in 64% of patients with ocular rosacea. Vitamins and minerals hold potential in managing rosacea symptoms, offering a safe and cost-effective alternative or adjunctive treatment option. Currently, there are no established recommendations regarding their supplementation for rosacea. Studies assessing serum levels of vitamins and minerals in relation to rosacea are warranted, as this avenue holds potential for future advancements in the field.

Omega-3 fatty acids supplements for dry eye - Are they effective or ineffective?

Purpose

To evaluate effectiveness of omega-3 fatty acid supplements in relieving dry eye symptoms and signs in symptomatic visual display terminal users (VDT).

Methods

A randomized controlled study was done; eyes of 470 VDT users were randomized to receive four capsules twice daily for 6 months (O3FAgroup), each containing 180 mg of eicosapentaenoic acid and 120 mg docosahexaenoic acid. The O3FA group was compared with another group (n = 480) who received four capsules of a placebo (olive oil) twice daily. Patients were evaluated at baseline, 1, 3, and 6 months, respectively. The primary outcome was improvement in omega-3 index (a measure of EPA and DHA ratio in RBC membrane). Secondary outcomes were improvement dry eye symptoms, Nelson grade on conjunctival impression cytology, Schirmer test values, tear film breakup time (TBUT), and tear film osmolarity. Means of groups (pre-treatment, 1, 3, and 6-months) were compared with repeated measure analysis of variance.

Results

At baseline, 81% patients had low omega-3 index. In the O3FA group, a significant increase in omega-3 index, improvement in symptoms, reduction in tear film osmolarity, and increase in Schirmer, TBUT, and goblet cell density was observed. These changes were not significant in the placebo group. Improvement in test parameters was significantly (P < 0.001) better in patients with low omega3 index (<4%) subgroup.

Conclusion

Dietary omega-3 fatty acids are effective for dry eye in VDT users; omega-3 index appears to be the predictor to identify potential dry eye patients who are likely to benefit from oral omega-3 dietary intervention.

Bilberry-containing supplements on severe dry eye disease in young and middle-aged adults: A 3-month pilot analysis

Purpose

To explore the effect of bilberry and fish oil combination supplement on a small clinical sample patient-base with severe dry eyes.

Methods

Twenty-four subjects were recruited with twelve randomly assigned to the intervention and control groups, respectively. Inclusion criteria included severe dry eye symptoms determined by scores >33 from the Ocular Surface Disease Index (OSDI) questionnaire. The intervention group was instructed to take an oral supplement with key ingredients of 600 mg bilberry extract and 240 mg docosahexaenoic acid-refined fish oil once daily for 3 months. The control group did not take any supplements. Mean changes in OSDI score, non-invasive tear break-up time (NITBUT), phenol red thread test (PRT), and percentage of meibomian gland openings were used as outcome measures. Testing was done at baseline, 1-month, and 3-month follow-up. Comparison between the treatment and control groups, and the younger adult and middle-age groups were performed.

Results

The mean baseline values for the treatment and control groups were not clinically different. The OSDI score, NITBUT, PRT, and percentage of meibomian gland openings improved after taking the supplements for 3 months. The OSDI score, NITBUT, and PRT showed clinical improvements between the intervention and control groups. These improvements were consistent between the two age groups.

Conclusion

This study suggested preliminary improvements in signs and symptoms of severe dry eyes that were independent of age after taking dietary supplementation of bilberry extract and fish oil for 3 months. Further studies using more device-based measures and a placebo supplement are warranted.

Topical Omega-3 Polyunsaturated Fatty Acids for the Treatment of Dry Eye - Results from a Pilot Randomized Controlled Masked-Observer Study

Purpose

To investigate the efficacy, safety and tolerability of topical omega-3 polyunsaturated fatty acids (PUFA) as an innovative treatment of dry eye disease (DED).

Patients and Methods

In a pilot, multicenter, masked-observer, randomized, active-controlled, non-inferiority study in Germany, patients self-treated their eyes with daily instillations of eye drops containing either omega-3 PUFA or povidone as major components for three months. At four and twelve weeks, efficacy was among others evaluated based on Ocular Surface Disease Index (OSDI), ocular surface symptoms intensity, general clinical impression, tear break-up time (TBUT), corneal fluorescein staining using the Oxford grading scale, tear volume, and matrix metalloproteinase-9 (MMP-9) concentration in the tear film. Safety evaluation included visual acuity, intraocular pressure, and the incidence of adverse events. Co-primary endpoints were the mean percent changes from baseline of TBUT and OSDI after four weeks.

Results

In total 80 patients were included, of whom 37 in the PUFA group and 39 in the povidone group were evaluable for the co-primary endpoints. Patients had a mean age of 52 years and >80% were women. Both co-primary endpoints (TBUT and OSDI) significantly improved from baseline in both treatment groups, at Week 4 and Week 12 and the statistical analysis demonstrated topical omega-3 PUFA to be non-inferior to 2% povidone for these two parameters. Both treatments resulted in a significant improvement of most secondary efficacy endpoints as well, often with a slight difference in favor of PUFA, not reaching statistical significance though. One non-severe, treatment-related local AE was reported in each group.

Conclusion

Omega-3 PUFA-based eye drops proved to be non-inferior to povidone-containing eye drops in the treatment of signs and symptoms of dry eye. This treatment may thus be an additional tool for the management of DED.

Nutraceuticals: A Promising Therapeutic Approach in Ophthalmology

Oxidative stress represents one of the main factors driving the pathophysiology of multiple ophthalmic conditions including presbyopia, cataracts, dry eye disease (DED), glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy (DR). Currently, different studies have demonstrated the role of orally administered nutraceuticals in these diseases. For instance, they have demonstrated to improve lens accommodation in presbyopia, reduce protein aggregation in cataracts, ameliorate tear film stability, break up time, and tear production in dry eye, and participate in the avoidance of retinal neuronal damage and a decrease in intraocular pressure in glaucoma, contribute to the delayed progression of AMD, or in the prevention or treatment of neuronal death in diabetic retinopathy. In this review, we summarized the nutraceuticals which have presented a positive impact in ocular disorders, emphasizing the clinical assays. The characteristics of the different types of nutraceuticals are specified along with the nutraceutical concentration used to achieve a therapeutic outcome in ocular diseases.

Oxidative Stress in the Protection and Injury of the Lacrimal Gland and the Ocular Surface: are There Perspectives for Therapeutics?

Oxidative stress (OS) is a major disruption in the physiology of the lacrimal functional unit (LFU). Antioxidant enzymes have dual protective activities: antioxidant and antimicrobial activities. Peroxidases have been indistinctly used as markers of the secretory activity of the LFU and implicated in the pathophysiology, diagnosis and treatment of dry eye disease (DED), even though they comprise a large family of enzymes that includes lactoperoxidase (LPO) and glutathione peroxidase (GPO), among others. Assays to measure and correlate OS with other local LFU phenomena have methodological limitations. Studies implicate molecules and reactions involved in OS as markers of homeostasis, and other studies identify them as part of the physiopathology of diseases. Despite these conflicting concepts and observations, it is clear that OS is influential in the development of DED. Moreover, many antioxidant strategies have been proposed for its treatment, including calorie restriction to nutritional supplementation. This review offers a critical analysis of the biological mechanisms, diagnostic outcomes, drug use, dietary supplements, and life habits that implicate the influence of OS on DED.

Effects of dietary high dose DHA omega-3 supplement in dry eye with meibomian gland dysfunction

AIM

To evaluate the clinical efficacy of dietary supplement of high dose DHA omega-3 in dry eye with meibomian gland dysfunction (MGD).

METHODS

Prospective randomized double-masked, placebo-controlled clinical trial was conducted in mild to moderate dry eye patients with MGD. Patients have no history of taking any dietary omega-3 supplements before 3mo. Patients were divided into two groups: 24 patients in the omega-3 group and 26 patients in the placebo group. The omega-3 group received two capsules of Easyeye Dry^®, total containing 600 mg of EPA and 1640 mg of DHA, while the placebo group received two capsules containing 3000 mg of olive oil. All patients take two pills once a day. The examination of MGD scores, tear break-up time (TBUT), corneal staining test (NEI), strip meniscometry (SM tube), and ocular surface disease index (OSDI) scores were performed at baseline, after 4 and 8wk.

RESULTS

A total of 50 patients were included. There were no differences in baseline characteristics between the two groups, such as age, sex, and other ocular examination findings. The TBUT, NEI, and OSDI scores significantly improved after 4 and 8wk in both groups. While after 8wk TBUT (6.00±1.62s vs 5.08±1.28s, P=0.034) and MGD score (7.2±1.8 vs 8.1±2.6, P=0.033) in the omega-3 group was more significantly improved than that of the placebo group.

CONCLUSION

Dry eye with the MGD patient, a high dose of DHA omega-3 dietary supplement can improve TBUT and MGD score after 8wk, effective in stabilizing the tear film.

Intestinal anti-inflammatory activity of Ulva ohnoi oil in DSS-induced experimental mouse model

This study was conducted to examine the physiological activity of Ulva ohnoi, some of which may be used for food or natural products but could disturbing coastal ecosystems due to large scale green-tide, to check values of U. ohnoi oil through experimental results. U. ohnoi oil was extracted from bulk of Ulva biomass to confirm its antioxidant and antibacterial activity, and the efficacy of U. ohnoi oil in the state of inflammation was confirmed through animal experiments. To confirm the anti-inflammatory effect, a mouse model induced with DSS was used. As a result of measuring NO using plasma after induction of inflammation, the amount of NO produced in the U. ohnoi oil group was decreased compared to the control group. Expression of inflammatory cytokines TNF-α, IL-6, and IL-1β was decreased compared to the control group. As a result of observing H&E staining, lower crypt loss and inflammatory cell infiltration were found in the U. ohnoi oil group compared to the control group. Consequently, U. ohnoi oil appears to have great anti-inflammatory properties.

Differential effects of dietary cholesterol and triglycerides on the lipid homeostasis in Meibomian glands

Exocrine Meibomian glands (MG) play a central role in the ocular surface physiology by producing meibum - a lipid secretion composed of cholesteryl esters (CE), cholesterol (Chl), triacylgycerols (TAG), waxes and other types of lipids. MG were previously shown to synthesize Meibomian lipids (ML) in situ via a complex array of reactions termed meibogenesis. However, questions remain about the role of dietary lipids in meibogenesis. To establish if dietary Chl (DC) and TAG (DT) can participate in meibogenesis, we studied mice whose diet was supplemented with trace amounts of deuterated Chl (2H-Chl) and 13C-labeled triolein (13C-TO), and the products of their biosynthetic transformations were analyzed using LC/MS. We demonstrated that 2H-Chl, but not 13C-TO, could be directly incorporated into meibum. Furthermore, 2H-Chl was esterified into MG-specific ultra long 2H-CE, which were vastly different from plasma CE and 2H-CE. The measured 2H-Chl/Chl and 2H-CE/CE ratios in meibum increased in a time-dependent manner reaching ∼5% and ∼1.2 %, respectively. The 2H-Chl/2H-CE ratio was about 3.5x higher than that for endogenous unlabeled Chl and CE, indicating accumulation of 2H-Chl in meibum. The elongation pattern of Meibomian 2H-CE closely replicated that of unlabeled CE. On the other hand, 13C-TO was not detected in any of the ML samples as an intact lipid or its metabolized/hydrolyzed products. We conclude that DC can be directly esterified into MG-specific CE, while DT undergo extensive catabolic transformations before reaching MG. These findings demonstrate that DC can have a direct impact on MG and ocular surface lipid homeostasis and pathophysiology.

Reliability of Chinese web-based ocular surface disease index questionnaire in dry eye patients: a randomized, crossover study

AIM

To assess the reliability of web-based version of ocular surface disease index in Chinese (C-OSDI) on clinically diagnosed dry eye disease (DE) patients.

METHODS

A total of 254 Chinese participants (51% male, 129/254; mean age: 27.90±9.06y) with DED completed paper- and web-based versions of C-OSDI questionnaires in a randomized crossover design. Ophthalmology examination and DED diagnosis were performed prior to the participants being invited to join the study. Participants were randomly designated to either group A (paper-based first and web-based second) or group B (web-based first and paper-based second). Final data analysis included participants that had successfully completed both versions of the C-OSDI. Demographic characteristics, test-retest reliability, and agreement of individual items, subscales, and total score were evaluated with intraclass correlation coefficients (ICC), Spearman rank correlation, Wilcoxon test and Rasch analysis.

RESULTS

Reliability indexes were adequate, Pearson correlation was greater than 0.8 and ICCs range was 0.827 to 0.982; total C-OSDI score was not statistically different between the two versions. The values of mean-squares fit statistics were very low compared to 1, indicating that the responses to the items by the model had a high degree of predictability. While comparing the favorability 72% (182/254) of the participants preferred web-based assessment.

CONCLUSION

Web-based C-OSDI is reliable in assessing DED and correlation with the paper-based version is significant in all subscales and overall total score. Web-based C-OSDI can be administered to assess individuals with DED as participants predominantly favored online assessment.

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.

Autoimmune Dry Eye without Significant Ocular Surface Co-Morbidities and Mental Health

Dry eye symptoms can negatively affect the psychological, physical, and social functioning, which can potentially impair the health-related quality of life. This review evaluated the association between autoimmune related dry eye in the absence of significant ocular surface co-morbidities and mental health. This review found a significantly higher prevalence of mental health disorders (such as depression and anxiety) in systemic lupus erythematous, rheumatoid arthritis, systemic sclerosis, Behcet’s disease, and primary Sjogren’s syndrome patients when compared to the general population. Moreover, patients with depression and anxiety interpret ocular sensations differently than healthy controls and the perception of dry eye symptoms can be influenced by their mood. Somatization is common in depression, and this could influence the perception of ocular discomfort. Anti-depressants and anxiolytics with their potential side effects on the tear film status may also contribute or aggravate the dry eye symptoms in these patients. Although ophthalmologists manage the dry eye disease, as per standardized algorithms, they should be mindful of different ocular sensation interpretation and coexistent mental health issues in a large number of this patient group and initiate a multidisciplinary management plan in certain cases. While rheumatologists look after their autoimmune condition, it may be worth liaising with GP and/or psychiatrist colleagues in order to address their neuropathic type pain and mental health co-morbidities.

Effect of Oral Choline Alfoscerate on Patients with Keratoconjunctivitis Sicca

Keratoconjunctivitis sicca (KCS) or dry eye is a disease characterized by ocular surface symptoms. This study aimed to investigate the effectiveness of oral choline alfoscerate (CA) administration as a treatment for KCS. The medical records of dry eye patients who were refractory to topical eyedrops and then took oral CA were reviewed. Results of tear break-up time (TBUT), fluorescein ocular surface staining score (FSS), and tear secretion by the Schirmer test (STT) were analyzed. The results of the ocular surface disease index (OSDI), visual analog pain score (VAS), reporting of the severity and frequency of symptoms, and the modified Standardized Patient Evaluation of Eye Dryness (SPEED) questionnaire were also analyzed. The records of 47 patients were analyzed for this study. The mean age was 62.8 ± 9.3 years, and the patients included 9 males and 38 females. TBUT, OSDI, and VAS significantly improved after CA administration compared to before (p < 0.05, paired t-test). After CA administration, symptom frequency and impact on life improved (p < 0.05, paired t-test). No significant change in photophobia or FSS was identified. In conclusion, oral CA administration was effective in improving tear stability and alleviating symptoms of KCS.

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 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.

The Dry Eye Assessment and Management (DREAM) extension study - A randomized clinical trial of withdrawal of supplementation with omega-3 fatty acid in patients with dry eye disease

PURPOSE

To determine effects of continued or discontinued use of omega-3 (ω3) fatty acid supplements through a randomized withdrawal trial among patients assigned to ω3 supplements in the first year of the DREAM study.

METHODS

Patients who were initially assigned to ω3 (3000 mg) for 12 months in the primary trial were randomized 1:1 to ω3 active supplements or placebos (refined olive oil) for 12 more months. The primary outcome was change in the Ocular Surface Disease Index (OSDI) score. Secondary outcomes included change in conjunctival staining, corneal staining, tear break-up time, Schirmer test, and adverse events.

RESULTS

Among 22 patients assigned to ω3 and 21 to placebo supplements, the mean change in OSDI score between month 12 and 24 was similar between treatment groups (mean difference in change -0.6 points, 95% confidence interval [CI], (-10.7, 9.5), p = 0.91). There were no significant differences between groups in mean change in conjunctival staining (difference in mean change -0.5 points; 95% CI (-1.2, 0.3)), corneal staining (-0.3 points; 95% CI (-1.2, 0.3)), tear break-up time (-0.8 s; 95% CI (-2.6, 0.9)) and Schirmer test (0.6 mm, 95% CI (-2.0, 3.2)). Rates of adverse events were similar in both groups.

CONCLUSION

Among patients who received ω3 supplements for 12 months in the primary trial, those discontinuing use of ω3 for an additional 12 months did not have significantly worse outcomes compared to those who continued use of ω3. ClinicalTrials.gov number NCT02128763.

Effects of Polyunsaturated Fatty Acids on Nonspecific Typical Dry Eye Disease: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

To investigate the effects of polyunsaturated fatty acids (PUFAs) in patients with dry eye disease (DED), a multifactorial inflammatory disorder, we searched Cochrane Library, EMBASE, PubMed, and Web of Science for randomized clinical trials (RCTs) investigating the effect of PUFAs in patients with DED before March 2019. Two reviewers independently abstracted data of tear breakup time (TBUT), Schirmer’s test, osmolarity, and ocular surface disease index (OSDI). We conducted pairwise meta-analysis using means and standard deviations (SDs) in a random-effects model for continuous outcomes. Thirteen eligible RCTs with 1782 patients with nonspecific typical DED were included. Patients who received PUFA treatment without other eye medications exhibited greater improvements in TBUT (MD = 1.80; p = 0.001), Schirmer test scores (MD = 0.50; p < 0.001), osmolarity (MD = −15.95; p < 0.001), and OSDI scores (MD = −10.19; p < 0.001) than those who received placebo treatment. However, the effects of PUFAs on TBUT (p < 0.001) and OSDI scores (p = 0.03) weakened with treatment duration. PUFAs are effective in treating nonspecific typical DED, particularly as a short-term treatment, with relatively few adverse events. Therefore, in real-world clinical practice, PUFA supplements are worth being suggested to patients with nonspecific typical DED who are not concurrently using other topical or systematic eye medications.

Effects of short-term oral vitamin A supplementation on the ocular tear film in patients with dry eye

Objective

To investigate the effects of short-term oral vitamin A supplementation on the ocular tear film in patients with dry eye.

Methods

In total, 30 male patients with dry eye (age range, 18–38 years; mean age, 25.2±2.8 years) who did not wear contact lenses or exhibit any ocular (other than dry eye) or systemic diseases were included, along with 30 age-matched men (control group; mean age, 24.5±2.3 years) with healthy eyes. Subject exclusion was based on the findings of the McMonnies questionnaire (cutoff score for dry eye: 14.5) and slit-lamp biomicroscopy. All subjects received an oral vitamin A supplement at a daily dose of 1,500 mg for 3 consecutive days. The phenol red thread (PRT) test was performed along with assessments of tear ferning (TF), tear osmolarity, and the tear break-up time (TBUT) before and 24 hours after the third dose of the vitamin A supplement. A 10-minute interval was observed between different tests.

Results

In the dry eye group, the TF grade (Wilcoxon test, P=0.01) exhibited a significant decrease, while the tear osmolarity value (t-test, P=0.01) exhibited a significant increase after vitamin A supplementation. The PRT test findings (P=0.17) and TBUT (P=0.49) showed no significant differences before and after vitamin A supplementation. In the control group, vitamin A supplementation showed no significant effects on TF (P=0.74), tear osmolarity (P=0.55), the TBUT (P=0.19), and the PRT test scores (P=0.48).

Conclusion

Our findings suggest that short-term oral vitamin A supplementation improves the quality, but not quantity, of tears in patients with dry eye. Future studies should involve larger patient samples and longer periods of vitamin A supplementation.

Dry Eye Assessment and Management (DREAM©) Study: Study design and baseline characteristics

PURPOSE

Describe trial design and baseline characteristics of participants in the DRy Eye Assessment and Management (DREAM©) Study.

DESIGN

Prospective, multi-center, randomized, double-masked "real-world" clinical trial assessing efficacy and safety of oral omega-3 (ω3) supplementation for the treatment of dry eye disease (DED).

METHODS

RESULTS: Mean age of participants was 58.0 ± 13.2 years. Mean OSDI score at baseline was 44.4 ± 14.2. Mean conjunctival staining score (scale 0-6) was 3.0 ± 1.4, corneal staining score (scale 0-15) was 3.9 ± 2.7, tear break-up time was 3.1 ± 1.5 s, and Schirmer test was 9.6 ± 6.5 mm/5 min.

CONCLUSIONS

DREAM© participants mirror real world patients who seek intervention for their DED-related symptoms despite their current treatments. Results regarding the efficacy of omega-3 supplementation will be helpful to clinicians and patients with moderate to severe DED who are considering omega-3 as a treatment. This trial design may be a model for future RCT's on nutritional supplements and DED treatments seeking to provide useful information for clinical practice.

TRIAL REGISTRATION

ClinicalTrials.gov number NCT02128763.

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

BACKGROUND

Dry eye disease is a common chronic condition that is characterized by ocular discomfort and visual disturbances that decrease quality of life. Many clinicians recommend the use of supplements of n-3 fatty acids (often called omega-3 fatty acids) to relieve symptoms.

METHODS

In a multicenter, double-blind clinical trial, we randomly assigned patients with moderate-to-severe dry eye disease to receive a daily oral dose of 3000 mg of fish-derived n-3 eicosapentaenoic and docosahexaenoic acids (active supplement group) or an olive oil placebo (placebo group). The primary outcome was the mean change from baseline in the score on the Ocular Surface Disease Index (OSDI; scores range from 0 to 100, with higher scores indicating greater symptom severity), which was based on the mean of scores obtained at 6 and 12 months. Secondary outcomes included mean changes per eye in the conjunctival staining score (ranging from 0 to 6) and the corneal staining score (ranging from 0 to 15), with higher scores indicating more severe damage to the ocular surface, as well as mean changes in the tear break-up time (seconds between a blink and gaps in the tear film) and the result on Schirmer's test (length of wetting of paper strips placed on the lower eyelid), with lower values indicating more severe signs.

RESULTS

A total of 349 patients were assigned to the active supplement group and 186 to the placebo group; the primary analysis included 329 and 170 patients, respectively. The mean change in the OSDI score was not significantly different between the active supplement group and the placebo group (-13.9 points and -12.5 points, respectively; mean difference in change after imputation of missing data, -1.9 points; 95% confidence interval [CI], -5.0 to 1.1; P=0.21). This result was consistent across prespecified subgroups. There were no significant differences between the active supplement group and the placebo group in mean changes from baseline in the conjunctival staining score (mean difference in change, 0.0 points; 95% CI, -0.2 to 0.1), corneal staining score (0.1 point; 95% CI, -0.2 to 0.4), tear break-up time (0.2 seconds; 95% CI, -0.1 to 0.5), and result on Schirmer's test (0.0 mm; 95% CI, -0.8 to 0.9). At 12 months, the rate of adherence to treatment in the active supplement group was 85.2%, according to the level of n-3 fatty acids in red cells. Rates of adverse events were similar in the two trial groups.

CONCLUSIONS

Among patients with dry eye disease, those who were randomly assigned to receive supplements containing 3000 mg of n-3 fatty acids for 12 months did not have significantly better outcomes than those who were assigned to receive placebo. (Funded by the National Eye Institute, National Institutes of Health; DREAM ClinicalTrials.gov number, NCT02128763 .).

Relation Between Dietary Essential Fatty Acid Intake and Dry Eye Disease and Meibomian Gland Dysfunction in Postmenopausal Women

PURPOSE

To evaluate the relationship between omega-3 (n-3) and omega-6 (n-6) fatty acids with dry eye disease (DED) and meibomian gland dysfunction (MGD).

DESIGN

Cross-sectional study.

METHODS

Postmenopausal women (n = 439) underwent a clinical evaluation and completed the Vio Food Frequency Questionnaire to estimate their dietary intake of n-3s and n-6s. Subjects were categorized into 2 binary classifications based on whether or not they had (1) DED and (2) MGD. Mean intake of dietary fatty acids was compared with 2-sample t tests. Univariate logistic regression models were used to estimate the odds ratios for each condition associated with each quintile of n-3s, n-6s, and n-6:n-3 ratios.

RESULTS

For DED vs non-DED, there were no significant differences in n-3 intake (1.95 ± 1.47 g vs 1.92 ± 1.24 g, P = .86), n-6 intake (15.58 ± 11.56 g vs 15.44 ± 10.61 g, P = .91), and n-6:n-3 (8.30 ± 2.57 vs 8.30 ± 2.57, P = .99). For MGD vs non-MGD, there were no significant differences in n-3 intake (1.87 ± 1.35 vs 1.96 ± 1.39, P = .61), n-6 intake (15.26 ± 11.85 vs 15.62 ± 10.93, P = .80), and n-6:n-3 (8.35 ± 2.94 vs 8.28 ± 2.42, P = .84). The odds ratios (OR) for DED did not differ significantly from 1.0 for n-3, n-6, or n-6:n-3. High n-3 consumption (OR = 0.22 [0.06–0.78]) and moderate n-6 consumption (OR = 0.37 [0.15–0.91]) were associated with a decreased frequency of MGD.

CONCLUSIONS

Dietary consumption of n-3s and n-6s showed no association with DED, but high n-3 consumption and moderate n-6 consumption were protective against MGD in this large sample of postmenopausal women.

Dietary Intakes of EPA and DHA Omega-3 Fatty Acids among US Childbearing-Age and Pregnant Women: An Analysis of NHANES 2001-2014

BACKGROUND

The 2015–2020 Dietary Guidelines for Americans (DGA) recommend that the general population should consume about 8 ounces (oz.) per week of a variety of seafood, providing approximately 250 mg per day of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and that pregnant and lactating women should consume 8–12 oz. per week of seafood.

METHODS

We determined the usual intakes, percentage not meeting recommendations, and trends in EPA and DHA intakes among childbearing-age and pregnant women (15–44 years of age) using the NHANES cycles 2001–2002 through 2013–2014.

RESULTS

For the childbearing-age women, the mean usual intake of seafood was 0.44 ± 0.02 oz. equivalent per day and 100% of the population was below the DGA recommendation. Mean usual intakes of EPA, DHA, and combined EPA and DHA from foods and dietary supplements combined were 26.8 ± 1.4, 62.2 ± 1.9, and 88.1 ± 3.0 mg per day, respectively. Over 95% of the sample did not meet the daily intakes of 250 mg EPA and DHA. Similar results were observed for pregnant women. After controlling for covariates, there were slight but significant increases in EPA and DHA intakes from foods and dietary supplements over the 14-year span among childbearing-age (p = 0.005) and pregnant women (p = 0.002).

CONCLUSIONS

It was estimated that a majority of U.S. childbearing-age and pregnant women consumed significantly lower amounts of seafood than what the DGA recommends, which subsequently leads to low intakes of EPA and DHA; in addition, dietary supplement use has not eliminated the nutrient shortfall.

Diet and rosacea: the role of dietary change in the management of rosacea

Dietary change may play a role in the therapy of rosacea. Certain foods and beverages may act as "triggers" for rosacea exacerbations. These may be divided into heat-related, alcohol-related, capsaicin-related, and cinnamaldehyde-related. One potential pathogenic mechanism may be via the activation of transient receptor potential cation channels, which result in neurogenic vasodilatation. Further research is needed on the role of the gut skin connection in rosacea. Epidemiologic studies suggest that patients with rosacea have a higher prevalence of gastrointestinal disease, and one study reported improvement in rosacea following successful treatment of small intestinal bacterial overgrowth. While further research is required in this area, patients may be advised on measures to support a healthy gut microbiome, including the consumption of a fiber-rich (prebiotic) diet.

Effect of Oral Re-esterified Omega-3 Nutritional Supplementation on Dry Eyes

PURPOSE

To assess the effect of oral re-esterified omega-3 fatty acids on tear osmolarity, matrix metalloproteinase-9 (MMP-9), tear break-up time (TBUT), Ocular Surface Disease Index (OSDI), fluorescein corneal staining, Schirmer score, meibomian gland dysfunction (MGD) stage and omega-3 index in subjects with dry eyes and confirmed MGD.

METHODS

This was a multicenter, prospective, interventional, placebo-controlled, double-masked study. Subjects were randomized to receive 4 softgels containing a total of 1680 mg of eicosapentaenoic acid/560 mg of docosahexaenoic acid or a control of 3136 mg of linoleic acid, daily for 12 weeks. Subjects were measured at baseline, week 6, and week 12 for tear osmolarity, TBUT, OSDI, fluorescein corneal staining, and Schirmer test with anesthesia. MMP-9 testing and omega-3 index were done at baseline and at 12 weeks.

RESULTS

One hundred five subjects completed the study. They were randomized to omega-3 (n = 54) and control group (n = 51). Statistically significant reduction in tear osmolarity was observed in the omega-3 group versus control group at week 6 (-16.8 ± 2.6 vs. -9.0 ± 2.7 mOsm/L, P = 0.042) and week 12 (-19.4 ± 2.7 vs. -8.3 ± 2.8 mOsm/L, P = 0.004). At 12 weeks, a statistically significant increase in omega-3 index levels (P < 0.001) and TBUT (3.5 ± 0.5 s vs. 1.2 ± 0.5 s, P = 0.002) was also observed. Omega-3 group experienced a significant reduction in MMP-9 positivity versus control group (67.9% vs. 35.0%, P = 0.024) and OSDI scores decreased significantly in omega-3 (-17.0 ± 2.6) versus control group (-5.0 ± 2.7, P = 0.002).

CONCLUSIONS

Oral consumption of re-esterified omega-3 fatty acids is associated with statistically significant improvement in tear osmolarity, omega-3 index levels, TBUT, MMP-9, and OSDI symptom scores.

The Role of Fish Oil in Inflammatory Eye Diseases

Consumption of fish oil is associated with reduced morbidity and mortality of cardiovascular diseases and also reduces the severity of many other inflammatory diseases and autoimmune disorders. The beneficial effects are attributed to the anti-inflammatory effects of the omega-3 polyunsaturated fatty acids, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), found in fish oils. The mechanism of the anti-inflammatory effects was long thought to be by modulating the production of proinflammatory mediators, including prostaglandins, thromboxanes, and leukotrienes. Recent advances in research into the novel lipid mediators (resolvins, protectins, and maresins) derived from EPA and DHA and their role in the resolution of inflammation have shed new light on the pleiotropic nature of these fatty acids. In this review, we focus on the effects of EPA and DHA from fish oil in the treatment of two common inflammatory eye diseases - dry eye disease and age-related macular degeneration. Evidence from recent studies lends support to a role of fish oil in the treatment of these two eye diseases.

Ocular Toxicity of Tyrosine Kinase Inhibitors

PURPOSE/OBJECTIVES

To review common tyrosine kinase inhibitors, as well as their ocular side effects and management.
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DATA SOURCES

A comprehensive literature search was conducted using CINAHL®, PubMed, and Cochrane databases for articles published since 2004 with the following search terms.

DATA SYNTHESIS

Tyrosine kinase inhibitors can cause significant eye toxicity.
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CONCLUSIONS

Given the prevalence of new tyrosine kinase inhibitor therapies and the complexity of possible pathogenesis of ocular pathology, oncology nurses can appreciate the occurrence of ocular toxicities and the role of nursing in the management of these problems.
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IMPLICATIONS FOR NURSING

Knowledge of the risk factors and etiology of ocular toxicity of targeted cancer therapies can guide nursing assessment, enhance patient education, and improve care management. Including a review of eye symptoms and vision issues in nursing assessment can enhance early detection and treatment of ocular toxicity.

Effects of adjuvant omega-3 fatty acid supplementation on dry eye syndrome following cataract surgery: A randomized clinical trial

PURPOSE

To investigate the effect of omega-3 polyunsaturated fatty acid supplement on qualitative and quantitative subjective (ocular surface disease index [OSDI]) and objective (Schirmer's test, tear break up time [TBUT], and tear osmolarity) dry eye indices after cataract surgery.

METHODS

In this randomized clinical study, 61 eyes of 48 patients complaining of new onset dry eye symptoms after phacoemulsification were enrolled. Subjects were randomly allocated into two groups using urn randomization. Controls received conventional treatment. The treatment group received omega-3 dietary supplement in addition to conventional therapy.

RESULTS

There was no significant difference between the control and treatment groups in pre-treatment indices of Schirmer (3.50 ± 3.13 and 2.96 ± 3.39, respectively, P = 0.582), TBUT (6.67 ± 1.36 and 4.87 ± 2.22, respectively, P = 0.687), osmolarity (316.66 ± 8.50 and 315.4 ± 17.06, respectively, P = 0.906), and OSDI (32.99 ± 19.03 and 35.32 ± 18.99, respectively, P = 0.635). Mean pre-treatment OSDI in the control group was 32.99 ± 19.03, which improved significantly after treatment to 25.43 ± 14.49 (P = 0.003). The mean pre-treatment OSDI in the treatment group was 35.32 ± 18.99 (range: 7.5-77.77), which improved significantly after treatment to 16.31 ± 13.72 (range: 2.77-47.22) (P < 0.001). OSDI improvement was significantly higher in the treatment group than the control group (P = 0.026). TBUT improved in both the control and treatment groups after treatment (P < 0.001). However, TBUT was affected significantly more in the treatment group compared with the control group (P = 0.038). Mean tear film osmolarity in the control group was 316.67 ± 8.50 (range: 308-325), which improved insignificantly after treatment to 311.33 ± 6.35 (range: 304-315) (P = 0.157). Mean pre-treatment tear film osmolarity in the treatment group was 315.40 ± 17.06 (range: 279-340), which improved significantly after treatment to 296.90 ± 14.39 (range: 260-310) (P < 0.001). Also, post-treatment Schirmer results between the two groups were not statistically significant (P = 0.155).

CONCLUSION

Omega-3 dietary supplements have an additive effect on tear film indices of patients with dry eye syndrome after phacoemulsification.

Omega-3 fatty acid supplementation improves dry eye symptoms in patients with glaucoma: results of a prospective multicenter study

PURPOSE

The purpose of this study is to assess the effectiveness and tolerability of a dietary supplement with a combination of omega-3 fatty acids and antioxidants on dry eye symptoms caused by chronic instillation of antihypertensive eye drops in patients with glaucoma.

PATIENTS AND METHODS

A total of 1,255 patients with glaucoma and dry eye symptoms related to antiglaucoma topical medication participated in an open-label, uncontrolled, prospective, and multicenter study and were instructed to take three capsules a day of the nutraceutical formulation (Brudypio(®) 1.5 g) for 12 weeks. Dry eye symptoms (graded as 0-3 [none to severe, respectively]), conjunctival hyperemia, tear breakup time, Schirmer I test, Oxford grading scheme, and intraocular pressure were assessed.

RESULTS

After 12 weeks of administration of the dietary supplement, all dry eye symptoms improved significantly (P<0.001) (mean 1.3 vs 0.6 for scratching, 1.4 vs 0.7 for stinging sensation, 1.6 vs 0.7 for grittiness, 1.0 vs 0.4 for tired eyes, 1.1 vs 0.5 for grating sensation, and 0.8 vs 0.3 for blurry vision). The Schirmer test scores and the tear breakup time also increased significantly. There was an increase in the percentage of patients grading 0-I in the Oxford scale and a decrease in those grading IV-V. Compliance was recorded in 62.5% of patients. In compliant patients, the mean differences at 12 weeks vs baseline of dry eye symptoms were statistically significant as compared to noncompliant patients.

CONCLUSION

Dietary supplementation with Brudypio(®) may be a clinically valuable additional option for the treatment of dry eye syndrome in patients with glaucoma using antiglaucoma eye drops. These results require confirmation with an appropriately designed randomized controlled study.

Conjunctival impression cytology versus routine tear function tests for dry eye evaluation in contact lens wearers

Aims:

Prolonged contact lens wear is often accompanied by dryness of the eyes. The aim of this study was to compare conjunctival impression cytology (CIC) and tear film tests such as tear film break up time (TBUT) and Schirmer test for dry eye evaluation in contact lens wearers and measure their correlation with dry eye symptoms.

Setting:

A case control study was done at three referral eye centers.

Materials and Methods:

The eyes of 230 contact lens users were compared to 250 eyes of age- and sex-matched controls. Participants were recruited based on their response to a questionnaire of dry eye symptoms, (Dry Eye Scoring System, DESS^©) and measurements of TBUT, Schirmer test, and CIC was done. A correlation analysis between symptom severity and tear film tests was performed. Pearson's coefficient, R² > 0.5 was considered significant.

Results:

As compared to controls (r² = 0.010), Nelson grade correlated significantly with dry eye symptoms (r² = 0.765), among cases. However, there was moderate correlation between dry eye symptoms, Schirmer test, and TBUT (r² = 0.557 and 0.530, respectively) among cases and a weak correlation among controls (r² = 0.130 and 0.054, respectively). The sensitivity of TBUT was 86.4%, specificity was 82.4%, positive likelihood ratio (LR) was 4.50 [95% confidence interval (CI) 3.46-5.85)], and negative LR was 0.09. The sensitivity of the Schirmer test was 48.2%, specificity 88%, LR 2.12 (95% CI 1.48-2.96), and negative LR 0.83.

Conclusion:

CIC correlates better than Schirmer and TBUT with dry eye symptoms. It may be the most appropriate test for dry-eye evaluation in contact lens wearers.

Pattern of astigmatism in a clinical setting in Maldives

BACKGROUND

Patterns of refractive errors have never been reported in Maldives. This study aims to dissect astigmatism and provide a general view in context of this island country.

METHODS

A clinic based cross sectional study was designed with 277 patients, aged ≥3.5 years and with a primary astigmatism of ≥-1.00 diopters (D). They underwent complete eye examination and a vector analysis was done.

RESULTS

Mean age was 28.58 (SD 19.15) years. Astigmatic magnitude depended on age (p<0.05) but not on gender (p>0.05). Severity of visual impairment after refractive correction was very less, with only 2.2% having visual acuity ≤6/60. Mean spherical, spherical equivalent and astigmatic refraction were -1.35 (SD 2.94 D), -2.40 (SD 3.04) and -2.12 (SD 1.11 D), respectively. Between fellow eyes, refractive and corneal astigmatism highly correlated (0.83 and 0.73). Fifty eyes (18.1%) had an astigmatic error of ≥-3.00 D which peaked in the second and third decades of life (p<0.0001) and was corneal in origin (p<0.0001). Internal J45 and J0 tended to be more negative with increasing age, showing a trend toward against the rule astigmatism. Correlation between corneal and refractive J0 and J45 were 0.88 and 0.62 (p<0.0001). With the rule astigmatism was more common followed by against the rule and oblique.

CONCLUSION

In conclusion, this study inferred that among patients with relatively higher magnitude of astigmatism attending to the clinics in Maldives, younger patients are affected more, which could possibly link to the environment, genetics and nutrition. The probable association between nutrition and astigmatism needs to be investigated to fill the gap in literature.

Burning Eye Syndrome: Do Neuropathic Pain Mechanisms Underlie Chronic Dry Eye?

OBJECTIVE

Dry eye is a multi-factorial disorder that manifests with painful ocular symptoms and visual disturbances, which can only be partly attributed to tear dysfunction. This disorder may also involve neuroplasticity in response to neuronal injury. This review will emphasize the key characteristics of dry eye pain and its pathologic mechanisms, making the argument that a subset of dry eye represents a neuropathic pain disorder of the eye, more appropriately called "burning eye syndrome."

METHODS

A literature review was conducted using a PubMed search focusing on dry eye, corneal nociception, and neuropathic pain. Articles were reviewed and those discussing clinical course, pathophysiology, and neuronal regulation of chronic ocular pain as related to dry eye were summarized.

RESULTS

We found that there is a discordance between ocular pain and dryness on the ocular surface. Although tear dysfunction may be one of the initial insults, its persistence may be associated with repeated ocular sensory nerve injury leading to an acute-to-chronic pain transition associated with neuropathologic changes (peripheral and central sensitization), neuronal dysfunction, and spontaneous ocular pain.

CONCLUSION

Dry eye is becoming a major health concern due to its increasing incidence, significant morbidity, and economic burden. Recent evidence suggests that a subset of dry eye may be better represented as a chronic neuropathic pain disorder due to its features of dysesthesia, spontaneous pain, allodynia, and hyperalgesia. Future therapies targeted at the underlying neuroplasticity may yield improved efficacy for patients with this subset of dry eye, which we term "burning eye syndrome."

Dietary Omega-3 Fatty Acids Suppress Experimental Autoimmune Uveitis in Association with Inhibition of Th1 and Th17 Cell Function

Omega (ω)–3 long-chain polyunsaturated fatty acids (LCPUFAs) inhibit the production of inflammatory mediators and thereby contribute to the regulation of inflammation. Experimental autoimmune uveitis (EAU) is a well-established animal model of autoimmune retinal inflammation. To investigate the potential effects of dietary intake of ω-3 LCPUFAs on uveitis, we examined the anti-inflammatory properties of these molecules in comparison with ω-6 LCPUFAs in a mouse EAU model. C57BL/6 mice were fed a diet containing ω-3 LCPUFAs or ω-6 LCPUFAs for 2 weeks before as well as after the induction of EAU by subcutaneous injection of a fragment of human interphotoreceptor retinoid-binding protein emulsified with complete Freund’s adjuvant. Both clinical and histological scores for uveitis were smaller for mice fed ω-3 LCPUFAs than for those fed ω-6 LCPUFAs. The concentrations of the T helper 1 (Th1) cytokine interferon-γ and the Th17 cytokine interleukin-17 in intraocular fluid as well as the production of these cytokines by lymph node cells were reduced for mice fed ω-3 LCPUFAs. Furthermore, the amounts of mRNAs for the Th1- and Th17-related transcription factors T-bet and RORγt, respectively, were reduced both in the retina and in lymph node cells of mice fed ω-3 LCPUFAs. Our results thus show that a diet enriched in ω-3 LCPUFAs suppressed uveitis in mice in association with inhibition of Th1 and Th17 cell function.

Neuropathic ocular pain: an important yet underevaluated feature of dry eye

Dry eye has gained recognition as a public health problem given its prevalence, morbidity, and cost implications. Dry eye can have a variety of symptoms including blurred vision, irritation, and ocular pain. Within dry eye-associated ocular pain, some patients report transient pain whereas others complain of chronic pain. In this review, we will summarize the evidence that chronicity is more likely to occur in patients with dysfunction in their ocular sensory apparatus (ie, neuropathic ocular pain). Clinical evidence of dysfunction includes the presence of spontaneous dysesthesias, allodynia, hyperalgesia, and corneal nerve morphologic and functional abnormalities. Both peripheral and central sensitizations likely play a role in generating the noted clinical characteristics. We will further discuss how evaluating for neuropathic ocular pain may affect the treatment of dry eye-associated chronic pain.

The diagnostic value and accuracy of conjunctival impression cytology, dry eye symptomatology, and routine tear function tests in computer users

AIMS AND OBJECTIVES

To compare the diagnostic value and accuracy of dry eye scoring system (DESS), conjunctival impression cytology (CIC), tear film breakup time (TBUT), and Schirmer's test in computer users.

METHODS

A case-control study was done at two referral eye centers. Eyes of 344 computer users were compared to 371 eyes of age and sex matched controls. Dry eye questionnaire (DESS) was administered to both groups and they further underwent measurement of TBUT, Schirmer's, and CIC. Correlation analysis was performed between DESS, CIC, TBUT, and Schirmer's test scores. A Pearson's coefficient of the linear expression (R (2)) of 0.5 or more was statistically significant.

RESULTS

The mean age in cases (26.05 ± 4.06 years) was comparable to controls (25.67 ± 3.65 years) (P = 0.465). The mean symptom score in computer users was significantly higher as compared to controls (P < 0.001). Mean TBUT, Schirmer's test values, and goblet cell density were significantly reduced in computer users (P < 0.001). TBUT, Schirmer's, and CIC were abnormal in 48.5%, 29.1%, and 38.4% symptomatic computer users respectively as compared to 8%, 6.7%, and 7.3% symptomatic controls respectively. On correlation analysis, there was a significant (inverse) association of dry eye symptoms (DESS) with TBUT and CIC scores (R (2) > 0.5), in contrast to Schirmer's scores (R(2) < 0.5). Duration of computer usage had a significant effect on dry eye symptoms severity, TBUT, and CIC scores as compared to Schirmer's test.

CONCLUSION

DESS should be used in combination with TBUT and CIC for dry eye evaluation in computer users.

Omega-3 essential fatty acids therapy for dry eye syndrome: a meta-analysis of randomized controlled studies

Background

Dry eye is a common, complex condition that can reduce ocular comfort and visual performance. The impact on quality of life has been rated as similar to the effect of moderate angina and, in more severe cases, dialysis and severe angina. This study aimed to use meta-analysis to compare omega-3 fatty acid and placebo fatty acid in the management of dry eye syndrome.

Material/Methods

Comparative studies published until 1 June 2014 were searched through a comprehensive search of the Medline, Embase, Web of Science, and the Cochrane Library electronic databases. A systematic review and cumulative analysis of comparative studies reporting the effect of omega-3 fatty acid on dry eye syndrome was conducted. All analyses were performed using the Review Manager (RevMan) v.5 software (Nordic Cochrane Centre, Copenhagen, Denmark).

Results

The trials involved a total of 790 participants in 7 independent studies. All the studies are published between 2007 and 2013. Meta-analysis of the 5 studies that reported data in mean SD values revealed that the tear break-up time (TBUT) was significantly greater by 1.58 s (WMD=1.58, 95% CI=0.60 to 2.55; P=0.007). Combination of all the Schirmer’s test data showed that omega-3 fatty acid supplementation could significantly improve the Schirmer’s test (WMD=0.74, 95% CI=0.29 to 1.19; P=0.001). However, the combination of all the OSDI test data showed that omega-3 fatty acid supplementation did not significantly improve the OSDI test results (WMD=−4.54, 95% CI=−9.85 to 0.78; P=0.09).

Conclusions

Based on the data included in our meta-analysis, omega-3 fatty acid was associated with better TBUT and Schirmer’s. No significant differences were detected in OSDI test results. Consequently, our findings suggest that omega-3 fatty acid offers is an effective therapy for dry eye syndrome.

Managing Sjögren's Syndrome and non-Sjögren Syndrome dry eye with anti-inflammatory therapy

Dry eye from Sjögren’s syndrome is a multifactorial disease that results in dysfunction of the lacrimal functional unit. Studies have shown changes in tear composition, including inflammatory cytokines, chemokines, and metalloproteinase. T-lymphocytes have been shown to increase in the conjunctiva and lacrimal glands in patient and animal models. This inflammation is in part responsible for the pathogenesis of the disease, which results in symptoms of eye irritation, ocular surface epithelial disease, and loss of corneal barrier function. There are a number of anti-inflammatory approaches for treating this disease. The current study reviews details of immune response and anti–inflammatory therapies used to control this disease.

Cataract surgery in patients with ocular surface disease: An update in clinical diagnosis and treatment

In this article we review essentials of diagnosis and management of ocular surface disease in patients who undergo cataract surgery. It is clearly shown that dry eye disease worsens following the cataract surgery in patients with prior history of ocular surface disease, Also new cases of dry eye might appear. Current strategies for the timely diagnosis and proper management of dry eye syndrome in the face of cataract surgery patients are mainly emphasized. To achieve the best outcome in cataract surgery, a healthy ocular surface is crucial. While ocular surface preparation is indispensable in patients with established ocular surface disease, it is also helpful in those with minimal signs or symptoms of surface disease. The current approach begins with early diagnosis and drastic management of ocular surface disease before cataract surgery using a stepwise regimen customized to each patient and disease severity. These measures are continued throughout and after the surgery.

The correlation of routine tear function tests and conjunctival impression cytology in dry eye syndrome

Purpose

To establish the strength of the association between routine tear function tests and conjunctival impression cytology (CIC) and to determine whether they simulate the morphological and cytological changes that occur on the ocular surface in dry eye. What are the sensitivity, specificity and positive predictive values of these tests when CIC is considered the gold standard?

Methods

The tear film profile included tear film break up time (TBUT), Schirmer's-1, Rose Bengal scores (RBS), and impression cytology. CIC samples were obtained from the inferior bulbar conjunctiva and stained with periodic acid-Schiff and counter stained with hematoxylin and eosin.

Results

The mean Schirmer's value was 11.66 ± 5.90 in patients and 17.17 ± 2.97 in controls (p < 0.001). The mean TBUT in participants was 8.88 ± 3.54 and 13.53 ± 2.12 in controls (p < 0.001). Patients had a mean goblet cell density (GCD) of 490 ± 213, while the value for controls was 1,462 ± 661 (p < 0.001). Abnormal CIC was observed in 46.7% cases of dry eye and in 32.8% of controls. The correlation coefficient (L) for Schirmer's was 0.2 and 0.24 for participants and controls, respectively, while TBUT values were 0.26 and 0.38, RBS were 0.5 and 0.5, and GCD was 0.8 and 0.6 in cases and controls, respectively.

Conclusions

GCD, RBS, and TBUT were better predictors of morphological and cytological changes in the conjunctiva than Schirmer's in dry eye syndrome. The sensitivity of tear function tests in diagnosing dry eye was TBUT > Schirmer's > RBS, and the specificity was Schirmer's > TBUT > RBS in decreasing order when CIC was considered the gold standard.