Prevalence of dry eye subtypes in clinical optometry practice

A Clinical Study of Subtype-based Prevalence of Dry Eye

INTRODUCTION

Dry Eye is a multifactorial disease of the tearfilm and the ocular surface which may be due to reduced tear production or excessive tear evaporation resulting in discomfort, visual disturbance, and tear film instability with a potential damage to the ocular surface. Various population-based studies have been done to find out the prevalence and the magnitude of the problem. Women Health Study reported prevalence of 7.8% after screening 36995 subjects above 49 years by interview. The prevalence reported by Blue Mountain Study was 15.3% .The Beaver Dam Study and Shiphai Eye studies are other studies reporting prevalence of 14.5% and 33.7% respectively. McMonnies questionnaire is a widely used screening instrument for Dry-Eye syndromes with sensitivity reportedly varying between 87% and 98% and specificity between 87% and 97%. Prevalence studies use McMonnie's questionnaire for screening individuals for Dry Eye, whereafter tests like Schirmer's test, Tear Film Break Up Time test, Rose Bengal test, Lissamine Green test and Meibomian Gland Dysfunction test are useful for further evaluation. While these tests help to differentiate the subtypes of Dry Eye such as Lipid Anomaly Dry Eye, Aqueous Tear Deficiency and Mucin Layer Deficiency, however, their sensitivity and specificity has not been widely studied. Additionally, very few studies have reported the prevalence of the various subtypes of Dry Eye.

AIM AND OBJECTIVES

To determine the subtype-based prevalence of Dry Eye, to study the specificity and sensitivity of clinical tests for Dry Eye and to correlate McMonnies questionnaire with Dry Eye tests results.

MATERIAL AND METHODS

A prospective, cross-sectional, observational study, duly approved by the Institutional Ethics Committee, was conducted from October 2010 to April 2012. A total of 4750 subjects above 18 yrs of age were screened by the McMonnies questionnaire. Respondents having a score greater than 14.5 were subjected to clinical Dry Eye tests. The data obtained was analyzed using chi-square test. p value < 0.005 was considered statistically significant.The specificity and sensitivity of each clinical test was calculated using Schirmer's test as gold standard.

RESULTS

The prevalence of Dry Eye was 15.4%, with a female preponderance (p = 0.01) and a significant increase with age above 60 years was noted (p<0.0001). Tear Film Break Up Time was the most reliable test with a good sensitivity (68.85%) and specificity (78.32%). Lipid Anomaly Dry Eye was the most prevalent (14.48%) followed by Aqueous Tear Deficiency (13.36%) and Mucin Layer Deficiency (3.51%). A positive correlation between McMonnies score and severity of Dry Eye was seen.

CONCLUSION

This study suggests that Lipid Layer Anomaly is the most prevalent subtype in Dry Eye. Tear Film Break Up Time test is the most likely test to diagnose mild Dry Eye. McMonies Questionnaire can be effectively used for screening of a large population. Tear Film Break Up Time was found to have better sensitivity as well as specificity than other tests used for diagnosing Dry Eye.

Prevalence of dry eye syndrome in an adult population

BACKGROUND

To determine the prevalence of dry eye syndrome in the general 40- to 64-year-old population of Shahroud, Iran.

DESIGN

Population-based cross-sectional study.

PARTICIPANTS

Through cluster sampling, 6311 people were selected and 5190 participated. Assessment of dry eye was done in a random subsample of 1008 people.

METHODS

Subjective assessment for dry eye syndrome was performed using Ocular Surface Disease Index questionnaire. In addition, the following objective tests of dry eye syndrome were employed: Schirmer test, tear break-up time, and fluorescein and Rose Bengal staining using the Oxford grading scheme.

MAIN OUTCOME MEASURES

Those with an Ocular Surface Disease Index score ≥23 were considered symptomatic, and dry eye syndrome was defined as having symptoms and at least one positive objective sign.

RESULTS

The prevalence of dry eye syndrome was 8.7% (95% confidence interval 6.9-10.6). Assessment of signs showed an abnormal Schirmer score in 17.8% (95% confidence interval 15.5-20.0), tear break-up time in 34.2% (95% confidence interval 29.5-38.8), corneal fluorescein staining (≥1) in 11.3% (95% confidence interval 8.5-14.1) and Rose Bengal staining (≥3 for cornea and/or conjunctiva) in 4.9% (95% confidence interval 3.4-6.5). According to the Ocular Surface Disease Index scores, 18.3% (95% confidence interval 15.9-20.6) had dry eye syndrome symptoms. The prevalence of dry eye syndrome was significantly higher in women (P = 0.010) and not significantly associated with age (P = 0.291). The objective dry eye syndrome signs significantly increased with age.

CONCLUSIONS

Based on the findings, the prevalence of dry eye syndrome in the studied population is in the mid-range. The prevalence is higher in women. Also, objective tests tend to turn abnormal at higher age. Pterygium is associated with dry eye syndrome and increased its symptoms.

Efficacy of an artificial tear emulsion in patients with dry eye associated with meibomian gland dysfunction

Objectives

The aim of the study reported here was to assess the efficacy of an artificial tear emulsion for the treatment of dry eye associated with meibomian gland dysfunction (MGD).

Methods

At five clinics, patients completed a 1-week treatment with their habitual topical therapy and then a 4-week treatment with open-label study medication: Systane® Balance Lubricant Eye Drops (Alcon, Alcon Inc, Fort Worth, TX, USA). Subjective assessments included a preference survey, the Impact of Dry Eye in Everyday Life questionnaire, and the Work Productivity and Activity Impairment questionnaire. Objective assessments by unmasked investigators included visual acuity, meibomian gland expression and dropout, tear film breakup time, corneal staining, and dosing frequency.

Results

At baseline, the 49 patients had mean meibomian gland expression grades and gland dropout that indicated mild to moderate MGD. Patients administered their habitual therapy 2.5 ± 1.3 times per day. After 4 weeks of study medication, the Impact of Dry Eye in Everyday Life questionnaire results indicated statistically and clinically significant improvements. Fewer than half of the participants were employed, limiting the usefulness of the Work Productivity and Activity Impairment questionnaire. Visual acuity remained statistically similar, while corneal staining and tear film breakup time improved significantly (P < 0.05) but modestly. The outcomes were achieved with 1.9 ± 1.1 doses per day of study medication, a significantly lower frequency than the habitual frequency (P < 0.001). The most common medication-related adverse event was blurred vision (3/49 patients, 6.1%). At study conclusion, 27/44 (61.4%) survey respondents preferred the study medication to their habitual therapy.

Conclusion

The artificial tear emulsion was effective for treating the signs and symptoms of dry eye in MGD patients.

Recent advances in topical ophthalmic drug delivery with lipid-based nanocarriers

Ocular barriers and the poor water solubility of drug candidates present a number of problems for the development of ocular drug delivery systems. Recently, the emergence of lipid-based nanocarriers has provided a viable means of enhancing the bioavailability of ophthalmic formulations. A number of these formulations have been found to be clinically active and several others are currently undergoing clinical trials. In this review, the advantages of lipid-based nanocarriers as non-invasive topical ocular drug delivery systems are presented. Many systems, including emulsions, liposomes, cubosomes, niosomes and other lipid-based nanocarriers, are reviewed.

Evaluation of dry eye

Dry eye is a common yet complex condition. Intrinsic and extrinsic factors can cause dysfunction of the lids, lacrimal glands, meibomian glands, ocular surface cells, or neural network. These problems would ultimately be expressed at the tear film-ocular surface interface. The manifestations of these problems are experienced as symptoms such as grittiness, discomfort, burning sensation, hyperemia, and secondary epiphora in some cases. Accurate investigation of dry eye is crucial to correct management of the condition. Techniques can be classed according to their investigation of tear production, tear stability, and surface damage (including histological tests). The application, validity, reliability, compatibility, protocols, and indications for these are important. The use of a diagnostic algorithm may lead to more accurate diagnosis and management. The lack of correlation between signs and symptoms seems to favor tear film osmolarity, an objective biomarker, as the best current clue to correct diagnosis.

The relationship between clinical signs and dry eye symptoms

PURPOSE

To evaluate (i) the relationship between traditional and new clinical tests (lid-wiper epitheliopathy (LWE), lid-parallel conjunctival folds (LIPCOF)) and dry eye symptoms in non-contact lens wearers, and (ii) that a combination of these tests can improve predictive ability for the development of dry eye symptoms.

METHODS

Tear meniscus height (TMH), non-invasive break-up time (NIBUT), ocular hyperaemia, LIPCOF, phenol red thread test (PRTT), corneal and conjunctival staining, and LWE grades were observed in a cohort of 47 healthy, non-lens wearers (male=17, female=30, median age=35 years, range=19-70). Symptoms were assessed using the Ocular Surface Disease Index (OSDI).

RESULTS

LWE was significantly correlated to both temporal and nasal LIPCOF (0.537 -0.248, P < 0.001). Significant correlations were found between NIBUT and TMH (r=0.461, P=0.001) and PRTT (r = 0.640, P < 0.001). OSDI scores were significant correlated to NIBUT, TMH, PRTT, LIPCOF, and LWE (r>∣0.31∣; P<0.05). Significant discriminators of OSDI+/- were NIBUT (area under the receiver operative characteristic curve (AUC)=0.895), TMH (0.715), PRTT (0.781), LIPCOF (temporal/nasal/Sum 0.748/0.828/0.816), and LWE (0.749). Best predictive ability was achieved by combining NIBUT with nasal LIPCOF (AUC=0.944).

CONCLUSIONS

The individual tests NIBUT, TMH, PRTT, LIPCOF, and LWE were significantly, but moderately, related to OSDI scores. The strongest relationship appeared by combining NIBUT with nasal LIPCOF.

Clinical trials of therapeutic ocular surface medium for moderate to severe dry eye

PURPOSE

To investigate therapeutic ocular surface medium (TOSM), a potential physiological tear replacement therapy, for moderate to severe dry eye.

METHODS

Forty-six patients with symptoms of moderate to severe dry eye despite maximal standard therapy were enrolled in a prospective pilot study of TOSM over 1 month (n = 10) and a randomized, double-masked, controlled trial of TOSM versus saline (placebo) over 2 months (n = 36). The primary outcome measure was conjunctival rose bengal staining.

RESULTS

An improvement in conjunctival rose bengal staining by ≥3 points occurred in 7 of 10 patients receiving TOSM in the pilot study (P = 0.017) and in 8 of 18 patients (44%) in the randomized trial (P = 0.982). In the pilot study, subjective dry eye symptoms significantly improved (P = 0.005). TOSM significantly improved the blepharitis score (P = 0.002) and conjunctival impression cytology (P = 0.028) in the randomized controlled trial. There were no serious or irreversible side effects with TOSM.

CONCLUSIONS

TOSM is a physiological tear replacement for dry eye that, unlike autologous serum, can be easily manufactured, could be widely available, and may also be beneficial for blepharitis.

Estimating the prevalence of dry eye among Indian patients attending a tertiary ophthalmology clinic

McMonnies' and Ocular Surface Disease Index (OSDI) questionnaires were used to estimate the prevalence of dry eye among 400 consecutive patients aged >40 years attending the ophthalmology outpatient department of the Lady Hardinge Medical College and associated Smt Sucheta Kriplani Hospital, in New Delhi, India. These estimates were then compared with the results of various clinical tests and examinations of the same patients, including Schirmer's tests, evaluations of tear-film breakup times and fluorescein staining of corneas. Although the overall prevalence of dry eye based on OSDI was 29.25%, there was considerable age- and gender-related variation in this parameter. Compared with the younger patients, those aged >or=80 years were more likely to have OSDI that were indicative of dry eye (41.2%), and the women investigated were more likely to have dry eye (as indicated by OSDI) than the men (27% v. 12%). Occupation, however, appeared to have no effect on the risk of dry eye (P=0.952). Grittiness was the commonest complaint reported. McMonnies' indices (MMI), OSDI and the values recorded in Schirmer's tests were all significantly and positively correlated with the probability of a clinical diagnosis of dry eye (P<0.001 for each). Only patients with a Schirmer's value of <8 mm showed fluorescein staining of the cornea (P<0.005). This appears to be the first report from India in which MMI and OSDI have been significantly correlated with the probability of a clinical diagnosis of dry eye. Although the subjects were recruited in an ophthalmology department and may not have been very representative of the general population of New Delhi, dry-eye syndrome is probably common in the study area and probably has a considerable socio-economic impact. The early detection and timely management of this syndrome is important, as they can help prevent long-term sequelae and sight-threatening complications.

Aging and topical pilocarpine concentrations effects on pupil size and tear flow rate

Purpose

This is to evaluate the effects of age and different concentrations of pilocarpine on tear flow rate and pupil size.

Methods

The tear flow rates and pupil sizes of eighty-one volunteers were measured with Schimer's strips and a meter rule gauge, respectively. These procedures were also employed in testing the effects of 2 % and 4 % concentrations of pilocarpine on tear secretion and pupil constriction.

Results

There were significant differences between the initial mean tear flow rate and the mean tear flow rates after the installation of 2 % pilocarpine (critical t = 1.96 and calculated t = 6.46) and 4 % pilocarpine (calculated t = 8.83). There were no significant differences in the initial tear flow rates between the sexes. There were significant differences between the mean tear flow rates obtained with 2 % and 4 % concentrations of pilocarpine (calculated t = 3.41). The mean initial tear flow rate for the eighty-one volunteers was 13.84 mm ± 1.19 (SD).There were significant differences between the mean initial pupil size 2.96 mm ± 1.04 (SD) and the mean pupil sizes 2.38 mm ± 1.11(SD) after the instillation of 2 % pilocarpine (Critical t = 1.96 and calculated t = 2.46).

Conclusion

The basal tear flow rate decreased with advancing age and topical pilocarpine increased tears secretion in all the age groups. The age groups (31 years and above) were more tolerant to the stinging effect of pilocarpine and induced reduced pupil sizes, but there were no significant differences between the mean pupil sizes obtained with the pilocarpine concentrations.

The eye--a neglected organ in environmental and occupational medicine: an overview of known environmental and occupational non-traumatic effects on the eyes

The objective of this study was to give an overview of the known literature data on the influence of environmental and occupational factors on the eye. Sixty-six articles were selected by searching Medline and PubMed databases using the following key words in different combinations: occupational and environmental factors, dry eye syndrome, cataract, retinal vascular changes. Most of the studies dealt with conditions on the eye surface and used eye discomfort syndrome and dry eye syndrome to outline the effects of air pollutants. Some reported increased frequency of lens opacities due to indoor fuel exposure, in particular biofuel, and negative effects of styrene exposure on colour vision. Investigations of retinal vascular changes and retinopathy after chronic exposure to carbon disulfide (CS2) and of retinal and choroidal haemodynamics after exposure to carbon monoxide (CO) found that CS2 caused an increase in retinal venous diameters and CO caused an increase in arterial and venous diameters, retinal blood flow velocity, and fundus pulsation amplitude. This article also discusses the influence of light exposure on retinal damage. It shows that very little information is available about the influence of environmental and occupational factors on the eye, and retina and retinal vessels in particular.

Dry eye syndrome (DES) and watering eyes

Dry eye symptoms and watering eyes increase with age and are relatively common among older people. The conditions cause distress which can be ameliorated if patients are advised appropriately. Accurate diagnosis of the underlying cause provides the basis for management. This paper outlines key features of the conditions and the range of therapies available.

Prevalence of dry eye in the normal population in Jeddah, Saudi Arabia

PURPOSE

To estimate the prevalence of dry eye disease in the normal non-complaining population.

METHODS

Prospective systematic random sampling study of 251 subjects who accompanied patients with appointments to the eye clinic. Interviewers administered a dry eye symptoms and risk factor questionnaire. Tear film break up time, fluorescein corneal staining and Schirmer's test were performed. Slit lamp examination to evaluate the lid margins, Meibomian glands and ocular surface structures was also performed.

RESULTS

Dry eye was diagnosed in 234 (93.2%) subjects on the basis of presence of one or more symptoms occurring often or most of the time, together with one or more of the following signs: tear film break up time < or = 10 seconds, fluorescein corneal staining > or = grade 1 and Schirmer test score < or = 5 mm. There was no statistically significant association between dry eye with advancing age or gender. Blepharitis was detected in 215 (91.9%) of the dry eye cases. Smoking was found to be the second most common risk factor as 18.8% of the dry eye cases were smokers. Sicca syndrome was found in 24.4% of the subjects.

CONCLUSION

Dry eye is very prevalent disease. Blepharitis was found to be very common among dry eye cases. There was no statistically significant association between dry eye and age or gender in our study population.

"Healthy" eye in office-like environments

Eye irritation symptoms, e.g. dry eyes, are common and abundant symptoms reported in office-like environments, e.g. aircraft cabins. To improve the understanding of indoor related eye symptomatology, relevant knowledge from the ophthalmological and indoor environmental science literature has been merged. A number of environmental (relative humidity, temperature, draft), occupational (e.g. visual display unit work), and individual (e.g. gender, use of cosmetics, and medication) risk factors have been identified, which are associated with alteration of the precorneal tear film (PTF); these factors may subsequently exacerbate development of eye irritation symptoms by desiccation. Low relative humidity including reduced atmospheric pressure further increases the water evaporation from an altered PTF; in addition, work with visual display units may destabilize the PTF by lower eye blink frequency and larger ocular surface. Results from epidemiological and clinical studies support that relative humidity >40% is beneficial for the PTF. Only few pollutants reach high enough indoor concentrations to cause sensory irritation of the eyes, while an altered PTF may exacerbate their sensory effect. Sustained low relative humidity causes impairment of the PTF, while its stability, including work performance, is retained by low gaze and intermittent breaks.

Tearful relationships? Sex, hormones, the lacrimal gland, and aqueous-deficient dry eye

Sex and the endocrine system exert a significant influence on the physiology and pathophysiology of the lacrimal gland. The purpose of this article is to briefly review the nature and magnitude of these interactions between sex, hormones and lacrimal tissue, and to address how they may relate to the pathogenesis of aqueous-deficient dry eye. Towards this end, this article has a 3-fold approach: first, to summarize the influence of androgens, estrogens, glucocorticoids, mineralocorticoids, retinoic acid, prolactin, alpha-melanocyte stimulating hormone, adrenocorticotropic hormone, luteinizing hormone, follicle-stimulating hormone, growth hormone, thyroid-stimulating hormone, arginine vasopressin, oxytocin, thyroxine, parathyroid hormone, insulin, glucagon, melatonin, human chorionic gonadotropin and cholecystokinin on the structure and function of the lacrimal gland; second, to discuss the mechanism of action of each hormone on lacrimal tissue; and third, to discuss the clinical relevance of the endocrine-lacrimal gland interrelationship, with a particular focus on each hormone's role (i.e. if relevant) in the development of aqueous-tear deficiency.

Tear lipid layer thickness and ocular comfort with a novel device in dry eye patients with and without Sjögren's syndrome

BACKGROUND

To measure changes in tear-film lipid-layer thickness (LLT) and symptoms in patients with dry eye symptoms with and without Sjögren's syndrome after using a novel device. The device is designed to promote release of meibomian sebum into the tear film by delivering latent heat to the eyelids.

STUDY DESIGN

Two prospective, controlled, randomised, observer-masked, single-intervention studies.

METHODS

Two independent studies were conducted in a major university hospital in the South West of England. The first study involved 24 patients with dry eye symptoms without Sjögren's [the PDE study] and the second study involved 31 patients with dry eye symptoms and Sjögren's syndrome (the SS study). The PDE study was randomised into two groups. Group I (12 patients) underwent 10 min of treatment with the activated device and Group II (12 patients) had no treatment. The SS study was similarly randomised into Group I (17 patients) and Group II (14 patients). The LLT and subjective alterations in ocular comfort of each subject were assessed prior and immediately after 5 and 30 min subsequent to the 10-min period. In the SS study, a further assessment was carried out at 60 min.

RESULTS

In the PDE study, treated patients exhibited a bilateral increase of LLT at 5 min (right eyes, 1.2 levels, p<0.0005; left eyes, 1.0 levels, p<0.0005, Mann-Whitney) and at 30 min (right eyes, 0.7 levels, p<0.005; left eyes, 0.6 levels, p<0.005). Mean symptom scores improved in the treated group compared with the control group at 5 min (treatment group, +2.0; control group, +0.2; p<0.05) and 30 min (treatment group, +2.8; control group, +0.4; p<0.015). In the SS study, treated patients exhibited a bilateral increase of LLT, 5 min (right eyes, 0.5 levels, p<0.009; left eyes, 0.5 levels, p<0.005, Monte Carlo 2-tailed), 30 min (right eyes, 0.5 levels, p<0.007; left eyes 0.5 levels, p<0.002) and 60 min (right eyes, 0.3 levels, p<0.1; left eyes, 0.3 levels, p<0.05). There was no change in any of the control patients in any of the assessments. With regard to symptom scores, the mean change at 5 min measured +0.8 in the treatment group and remained relatively unchanged at +0.1 in the control group (p<0.1). At 30 min, this change measured +1.3 in the treatment group and +0.1 in the control group (p<0.03) and at 60 min, the change measured +1.5 in the treatment group and remained at +0.1 in the control group (p<0.02).

CONCLUSION

Meibomian therapy with this novel device increases LLT and ocular comfort in patients with dry eye symptoms with and without Sjögren's syndrome.

Tear secretion dysfunction among women workers engaged in light-on tests in the TFT-LCD industry

Background

The TFT-LCD (thin film transistor liquid crystal display) industry is rapidly growing in Taiwan and many other countries. A large number of workers, mainly women, are employed in the light-on test process to detect the defects of products. At the light-on test workstation, the operator is generally exposed to low humidity (in the clean room environment), flashing light, and low ambient illumination for long working hours. Many workers complained about eye discomfort, and therefore we conducted a study to evaluate the tear secretion function of light-on test workers of a TFT-LCD company.

Methods

We recruited workers engaged in light-on tests in the company during their periodical health examination. In addition to a questionnaire survey of demographic characteristics and ophthalmic symptoms, we evaluated the tear secretion function of both eyes of each participant using the Schirmer's lacrimal basal secretion test with anaesthesia. A participant with one or both eyes yielding abnormal test results was defined as a case of tear secretion dysfunction.

Results

During the study period, a total of 371 light-on test workers received the health examination at the clinic of the park, and 52 of them were excluded due to having ophthalmic diseases and other systemic diseases that may affect ophthalmic function. All the remaining 319 qualified workers agreed to participate in this study, and they were all females working by 4-shift rotations. The average age was 24.2 years old (standard deviation [SD] = 3.8), and the average employment duration was 13.6 months (SD = 5.7). Among the 11 ophthalmic symptoms evaluated, eye dryness was the most prevalent (prevalence = 43.3%). In addition, the prevalence of tear secretion dysfunction in at least one eye was 40.1% (128 cases), and contact lens users had an odds ratio of 1.73 (95% confidence interval = 1.02–2.94) in comparison with non-contact lens users. Comparing the Schirmer's test results of those who also participated in the screening in the previous year, we found 40 of the 156 participants (17.2%) with normal test results in the previous year turned abnormal in 2001. In contrast, only 21 of the 76 participants (9.1%) with abnormal test results in the previous year turned normal, and the difference was statistically significant (p = 0.02 for McNemar's test).

Conclusion

The prevalence of tear secretion dysfunction in woman workers engaged in light-on tests is high and increases with a one-year duration of employment. The use of contact lens may further increase the risk.

Effect of yoga on self-rated visual discomfort in computer users

BACKGROUND

'Dry eye' appears to be the main contributor to the symptoms of computer vision syndrome. Regular breaks and the use of artificial tears or certain eye drops are some of the options to reduce visual discomfort. A combination of yoga practices have been shown to reduce visual strain in persons with progressive myopia. The present randomized controlled trial was planned to evaluate the effect of a combination of yoga practices on self-rated symptoms of visual discomfort in professional computer users in Bangalore.

METHODS

Two hundred and ninety one professional computer users were randomly assigned to two groups, yoga (YG, n = 146) and wait list control (WL, n = 145). Both groups were assessed at baseline and after sixty days for self-rated visual discomfort using a standard questionnaire. During these 60 days the YG group practiced an hour of yoga daily for five days in a week and the WL group did their usual recreational activities also for an hour daily for the same duration. At 60 days there were 62 in the YG group and 55 in the WL group.

RESULTS

While the scores for visual discomfort of both groups were comparable at baseline, after 60 days there was a significantly decreased score in the YG group, whereas the WL group showed significantly increased scores.

CONCLUSION

The results suggest that the yoga practice appeared to reduce visual discomfort, while the group who had no yoga intervention (WL) showed an increase in discomfort at the end of sixty days.

Prevalence of Dry Eye in Bangkok, Thailand

PURPOSE

To estimate the prevalence of dry eye in the adult population of Bangkok, Thailand.

METHODS

Five hundred fifty volunteers 40 years of age or more who presented to the Ramathibodi Hospital for annual eye examinations were enrolled. Interviewers administered a dry eye symptoms questionnaire. Slit-lamp examination and objective dry eye assessment consisting of tear film breakup time (TBUT), fluorescein corneal staining, Schirmer tests, and meibomian gland evaluation were performed. Outcome measures included frequency of symptoms and positive dry eye tests.

RESULTS

Thirty-four percent reported significant symptoms, which were defined as having one or more symptoms often or all of the time (95% confidence interval, 28.1-40.6). Approximately one half had meibomian gland disease (MGD) or pingueculum/pterygium (46.2 and 53.8%, respectively). Individuals with significant symptoms tended to be women (83.4%, P = 0.024), had MGD (63.6%, P = 0.006), had current artificial tear use (33.2%, P = 0.024), and had positive TBUT (80.7%, P = 0.000) and fluorescein staining (16.6%, P = 0.013.) The presence of pingueculum/pterygium and MGD were significantly associated with positive dry eye tests.

CONCLUSION

This is the first report of prevalence of dry eye inclusive of signs and symptoms in an elderly Thai population. The prevalence of disease diagnosed on the basis of symptoms and dry eye tests was approximately 2 to 3 times higher than reported in whites. Women were more likely to report symptoms. Positive associations with dry eye tests were found in subjects with pingueculum/pterygium and MGD.

Distribution of Conjunctival HLA-DR Expression and the Pathogenesis of Damage in Early Dry Eyes

PURPOSE

To examine the expression of HLA-DR, a marker of inflammation, in the early stages of dry eye disease and to locate the appearance of this marker on specific areas of the bulbar conjunctiva.

METHODS

Dry eye patients were identified and their condition classified as mild (n = 16) or moderate (n = 16) based on Schirmer testing, vital staining, tear break-up time, and symptom questionnaire scores. Brush cytology was used to collect epithelial cells from the nasal, temporal, and superior conjunctivae of patients and age-matched controls. HLA-DR positive cells were detected by immunohistochemical staining and quantified.

RESULTS

Patients with moderate dry eye had the highest rate of conjunctival HLA-DR-positive cells, with significantly higher rates than controls regardless of which region of the conjunctiva was sampled (P < 0.01). The mild dry eye group had similar rates of HLA-DR-positive cells in the superior conjunctival region compared with controls. However, in the nasal and temporal regions, they displayed a significantly higher rate of HLA-DR-positive cells than controls (P < 0.01) and the nasal region showed a significant difference (P < 0.01) when compared with the temporal one. Some of these mild dry eyes had no vital staining.

CONCLUSIONS

The HLA-DR expression pattern in mild and moderate dry eyes appears to reflect disease progression. Overexpression of HLA-DR in mild dry eyes showing no vital staining suggests that inflammation may be a primary cause of ocular surface damage. These data support the use of immunomodulatory drugs in the treatment of dry eye disease.

Comparing the discriminative validity of two generic and one disease-specific health-related quality of life measures in a sample of patients with dry eye

OBJECTIVE

The purpose of this study was to compare the discriminative properties of two generic health-related quality of life (QoL) instruments (SF-36 and EQ-5D) and a newly developed disease-specific patient-reported outcomes instrument (Impact of Dry Eye on Everyday Life (IDEEL)) to distinguish between different levels of dry eye severity.

METHODS

Assessment of 210 people: 130 with non-Sjogren's Keratoconjunctivitis Sicca (non-SS KCS), 32 with Sjögren's Syndrome (SS) and 48 controls; comparison of SF-36, EQ-5D, and IDEEL age-adjusted data by dry eye severity levels. Severity was assessed based on diagnosis (non-SS KCS, SS, control), patient-report (none, very mild, mild, moderate, severe, extremely severe) and clinician-report (none, mild, moderate, severe).

RESULTS

Discriminative validity results were consistent for all instruments. Significant differences between severity levels were found with most SF-36 scales (P < 0.05), all EQ-5D scales (P < 0.05), and all IDEEL scales (P < 0.0001), except for Treatment Satisfaction. IDEEL scales consistently outperformed the generic QoL measures regardless of the severity criterion used. Most SF-36 scales outperformed the EQ-5D QoL scale, but the EQ-5D visual analog scale outperformed the SF-36 scales, except for General Health Perceptions.

CONCLUSIONS

The disease-specific IDEEL scales are better able to discriminate between severity levels than the majority of the generic QoL scales. Preliminary evidence demonstrates that the IDEEL will be sensitive to QoL changes over time, although further testing in controlled longitudinal studies is needed.

Eye complaints in the office environment: precorneal tear film integrity influenced by eye blinking efficiency

To achieve a common base for understanding work related eye complaints in the office environment, it is necessary to merge approaches from indoor air science, occupational health, and ophthalmology. Based on database searches, it is concluded that precorneal tear film (PTF) alteration leads to eye complaints that may be caused by: (1) thermal factors (low relative humidity; high room temperature); (2) demanding task content (attention decreases blinking and widens the exposed ocular surface area); and (3) individual characteristics (for example, tear film alterations, blinking anomalies, gland dysfunctions, and use of contact lenses). These factors and conditions are able to progressively increase water evaporation and faster thinning of the PTF, which causes dryness and dry spot formation on the cornea, possibly followed by corneal and conjunctiva epithelial alterations and eye complaints. Another possible cause of eye complaints is certain irritating chemical compounds, in addition to oxidation mixtures that are formed in reactions between ozone and unsaturated organic compounds (alkenes). The effect may be exacerbated by low relative humidity.

The Economic Burden of Dry Eye

PURPOSE

To develop a conceptual framework for analyzing the economic burden of dry eye and a preliminary assessment of key factors that contribute to that burden.

METHODS

The MEDLINE database was searched from 1966 to May 2003 combining the term "dry eye" with various economic terms. In addition, individual interviews with a panel of clinicians were conducted to provide additional insight on resource use.

RESULTS

Direct resource utilization among dry eye sufferers includes healthcare professional visits, nonpharmacological therapies, pharmacological treatments, and surgical procedures, with the latter 2 categories being the major cost drivers. Complementary and alternative medicine (CAM) therapies are a newly recognized component of the dry eye economic burden. There is wide variation in patterns of diagnosis and treatment, but current therapies are not universally effective. Given the prevalence of the condition, indirect costs may be large. Utilization of pharmacological therapies, especially those other than tear replacements, the extent of CAM use, cost of complications of surgical procedures, and indirect costs are unknown. The natural history and probability that patients will transition between therapies, based on underlying disease severity, need to be elucidated.

CONCLUSIONS

Dry eye is a prevalent condition with the potential for a high economic burden; additional studies are needed to further characterize the economic impact.

Prevalence and associations of dry eye syndrome in an older population: the Blue Mountains Eye Study

This report describes the prevalence of self-reported dry eye syndrome and associations with systemic and ocular factors in an older Australian population. Participants of the Extension Blue Mountains Eye Study, aged 50 or older (mean age 60.8 years, n = 1174) completed a comprehensive eye examination and dry eye questionnaire. At least one dry eye symptom was reported by 57.5% of participants, with 16.6% reporting moderate to severe symptoms, more frequent in women (age-adjusted odds ratio [OR] 1.5, 95% confidence interval [CI] 1.1-2.2). Three or more symptoms were reported by 15.3% of participants, also more frequent in women (age-adjusted OR 1.7, CI 1.2-2.4). No age-related trends or significant ocular associations were observed. After adjusting for age and sex, systemic factors significantly associated with dry eye syndrome included history of arthritis, asthma, gout, use of corticosteroids, antidepressants and hormone replacement therapy. In this older population, dry eye syndrome was common and has associations with female gender and systemic diseases.

Effect of Laser in situ Keratomileusis for Hyperopia on Tear Film and Ocular Surface

PURPOSE

To examine the effects of laser in situ keratomileusis (LASIK) for hyperopia on the tear film and ocular surface.

METHODS

A retrospective 12-month analysis of 88 eyes (88 participants) who had LASIK for hyperopia was performed. Participants were evaluated before and after (2 weeks, 1, 3, 6, and 12 months) surgery for dry eye symptoms (McMonnies Dry Eye Survey primary symptoms), tear film stability (fluorescein break-up time), tear volume (phenol red thread test), ocular surface staining (fluorescein), and conjunctival goblet cell density.

RESULTS

Chronic dry eye was experienced by 32% of participants; symptoms were significantly associated with female gender, preoperative dry eye symptoms, lower tear film stability after surgery, greater ocular surface staining after surgery, lower tear volume before and after surgery, and lower goblet cell densities after surgery. Regression rate 12 months after surgery was 32% and significantly associated with female gender, chronic dry eye symptoms, lower tear film stability after surgery, greater ocular surface staining before and after surgery, and lower tear volume before and after surgery.

CONCLUSIONS

Dry eye, particularly in females, is problematic after LASIK for hyperopia and is associated with refractive regression. Current methods for managing the tear film and ocular surface may not control LASIK-induced dry eye, particularly in some females during the first 6 months after surgery.

Dry eye: an update on clinical diagnosis, management and promising new treatments

Dry eye conditions are prevalent with one in four to five patients presenting to eye care practitioners having dry eye signs and/or symptoms. An intimate relationship exists between the ocular surface and the tear film. The cycle of tear film instability and ocular surface damage characteristic of dry eye conditions suggests that dry eye represents a dysfunction of an integrated ocular surface-lacrimal gland unit. Therefore, dry eye is a multifactorial condition and an approach based on clinical subtypes is required for diagnosis and management. There is increasing evidence that inflammation is a contributing and exacerbating factor in dry eye conditions and anti-inflammatory or immunomodulatory therapy for chronic dry eye conditions may facilitate ocular surface healing. Other promising new treatments for dry eye include new generation artificial tear polymers and preservative systems, secretagogues, topical androgen supplements and surgical techniques for ocular surface reconstruction.