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.

The Discriminatory Ability of Ganglion Cell Inner Plexiform Layer Complex Thickness in Patients with Preperimetric Glaucoma.

Purpose: To evaluate diagnostic performance of ganglion cell inner plexiform layer (GCIPL) and retinal nerve fiber layer (RNFL) parameters measured with Cirrus high-definition optical coherence tomography (OCT) in patients with preperimetric glaucoma. Methods: In this multicenter cross-sectional study, 150 eyes of 83 patients with preperimetric glaucoma were compared with 200 eyes of age and sex matched healthy subjects. All patients had visual field testing and OCT scanning of GCIPL and RNFL in all quadrants. The independent Samples t-test was used to determine if a difference exists between the means of two independent groups on a continuous dependent variable. The area under the receiver operating characteristic (ROC) curve (AUC) of each parameter was calculated for discriminatory ability between normal controls and preperimetric glaucoma. The sensitivity and specificity were estimated by point coordinates on ROC curve. Results: The best parameters for distinguishing preperimetric glaucoma from healthy eyes were the combined average GCIPL + average RNFL, followed by average RNFL + GCIPL (inferotemporal), and average RNFL + GCIPL (minimum). The GCIPL parameters with the highest to lowest AUC (in decreasing order) were inferotemporal, followed by average, minimum, superior, inferior, superonasal, inferonasal, superotemporal, and quadrants. The RNFL parameters with the highest to lowest AUC (in decreasing order) were average, followed by nasal, temporal, superior, and inferior quadrants. The sensitivity of combined GCIPL + RNFL parameters ranged 85%-88% and the specificity ranged 76%-88%. The sensitivity for RNFL parameters ranged 80%-90% and the specificity ranged 64%-88%. Conclusion: GCIPL and RNFL have good discriminatory ability; the sensitivity and specificity increase when both parameters are combined for early detection of glaucoma.

A Randomized Controlled Trial of Omega 3 Fatty Acids in Rosacea Patients with Dry Eye Symptoms.

Objective or purpose: To evaluate the efficacy of dietary omega-3 fatty acids (O3FAs) in rosacea patients having dry eye symptoms. METHODS: A prospective, interventional, randomized, double-masked, placebo-controlled, multi-centric study was done. Symptomatic patients with rosacea were recruited based on their response to (Dry Eye Scoring System, DESS©); a score of 0-3 was assigned to dry eye-related symptoms like ocular fatigue, blurring of vision, itching or burning, sandy or gritty sensation, and redness, respectively (DESS©). Subjects were (n = 130) were randomized to receive either O3FAs (n = 65) or placebo (n = 65) capsules (olive oil) twice daily for 6 months. Patients were evaluated at baseline, 1, 3, and 6 months. Change in subjective dry eye symptoms was the primary outcome measure. Change in meibomian gland score (MGS), Schirmer score, and tear film breakup time (TBUT) were the secondary outcome measures. RESULTS: Repeated-measures ANOVA revealed that there was a significant (p < 0.001) change in symptoms (F(1.506, 88.825 = 315.193), MGS (F(1.336, 78.796 = 84.438), Schirmer score (F(1.322, 78.022 = 86.559), and TBUT (F(1.354, 79.898 = 179.020.559) in O3FA group as compared to placebo group. Post-hoc test revealed that there was a significant change in dry eye symptoms at all points of time; there was a significant change in MGS, Schirmer score, and TBUT also, but only after 3 months of intervention. Linear regression established that symptom severity could significantly predict MGS, Schirmer score, and TBUT. There was a significant change in the slope (intercept) of the regression plots in O3FA group as compared to the placebo group. CONCLUSION: Rosacea patients with dry eye symptoms have significant improvement in symptoms, MGS, TBUT, and Schirmer score, following dietary intervention with O3FAs for 6 months.

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.