Androgen control of gene expression in the rabbit meibomian gland

Dry eye and dry skin - is there a connection?

AIM

To enquire whether patients with dry eye symptoms also report dry skin, whether their perception could be corroborated with objective measurement, and whether dry eye disease might be suspected based on patients' complaints.

METHODS

This cross-sectional study included 50 subjects, 25 with and 25 without dry eye symptoms. Schein questionnaire was used to determine the severity of dry eye symptoms. Ocular signs were assessed by monitoring conjunctival hyperemia, ocular surface staining, meibomian gland expression, tear film lipid layer thickness, tear break-up time, lid parallel conjunctival folds, Schirmer test, and meibometry. Skin dryness was assessed by noting patients' self-perception of their facial skin dryness and measured by sebumeter.

RESULTS

Subjects without dry eye symptoms had self-reported oilier facial skin than those with dry eye symptoms (p < .001). Sebumetry scores measured on the forehead and cheek were significantly higher in subjects without dry eye symptoms than dry eye subjects (p = .003). After adjustment for age and gender in a logistic regression analysis, dry eye was independently and significantly associated with dry skin (AOR 0.69, p = .040), higher LIPCOF score of both eyes (AOR 2.28, p = .028), lower sebumetry score of the forehead (AOR 0.98, p = .041) and cheek (AOR 0.98, p = .041), and shorter TBUT score after gland expression (AOR 0.90, p = .018).

CONCLUSION

This study showed that ocular dryness was subjectively and objectively positively correlated to facial skin dryness. Patients reliably described their skin condition. People with dry facial skin also had drier eyes.

Meibomian Gland Assessment in Routine Ophthalmology Practice

This cross-sectional study aimed to investigate the connection between meibomian gland (MG) excreta quantity and quality after MG expression (MGX), dry eye disease (DED) symptoms, and objective DED signs and to clarify the relationship between dry eye and MG function in DED pathophysiology. The study included 200 subjects, 100 with and 100 without dry eye symptoms. Schein questionnaire was used to determine the severity of dry eye symptoms and self-reported skin type for facial skin dryness self-evaluation. Objective dry eye signs were assessed by monitoring conjunctival hyperemia, lid parallel conjunctival folds (LIPCOF), tear break-up time (TBUT), fluorescein surface staining and digital MGX. Subjects with DED symptoms had significantly lower MG quantity scores than healthy controls (p < 0.001). Meibum quality and quantity scores significantly correlated with female gender (p = 0.002), Schein questionnaire score (p < 0.001), fluorescein corneal staining score (p = 0.019), self-reported skin type (p < 0.001), TBUT (p < 0.001) and LIPCOF (p = 0.041). After adjustment for age and gender in a logistic regression analysis, dry eye was independently and significantly associated with self-reported skin type (OR 0.73, p < 0.001), LIPCOF (OR 1.04, p < 0.001), fluorescein corneal staining (OR 1.05, p = 0.019), TBUT (OR 0.77, p < 0.001) and meibum quantity score (OR 0.59, p < 0.001). Dry eye symptoms and objective signs correlated well in this study. MGX discriminated between the subjects with and without DED symptoms and was associated with other objective DED signs. Results showed a significant association between meibum quality and quantity, MG function, DED and facial skin dryness self-perception. This paper established a correlation between dry eye symptoms caused by MG dysfunction and dry skin, which can help general health practitioners consider dry eye as a cause of chronic eye complaints with patients who report dry skin.

Meibomian Gland Dysfunction: What Have Animal Models Taught Us?

Studies have estimated that currently 344 million people worldwide and 16.4 million adults in the US have some form of dry eye disease (DED). It is believed that approximately 70% of DED cases are due to some form of evaporative dry eye, for which Meibomian gland dysfunction (MGD) is the major cause. Unfortunately, currently there is no effective treatment for MGD, and solely palliative care is available. Given the importance of MGD in DED, there has been a growing interest in studying Meibomian gland development, homeostasis and pathology, and, also, in developing therapies for treating and/or preventing MGD. For such, animal models have shown to be a vital tool. Much of what is known today about the Meibomian gland and MGD was learnt from these important animal models. In particular, canine and rabbit models have been essential for studying the physiopathology and progression of DED, and the mouse model, which includes different knockout strains, has enabled the identification of specific pathways potentially involved in MGD. Herein, we provide a bibliographic review on the various animal models that have been used to study Meibomian gland development, Meibomian gland homeostasis and MGD, primarily focusing on publications between 2000 and 2020.

The effects of adjuvant hormonotherapy on tear functions in patients with breast cancer

PURPOSE

Aromatase inhibitors (anastrozole, letrozole) and selective estrogen receptor modulators (tamoxifen) are widely used as adjuvant hormonal therapy in women with hormone receptor-positive breast cancer. We aimed to evaluate the effects of oral adjuvant hormonotherapy on tear functions in patients with breast cancer.

METHODS

In this case-control study, we enrolled eligible patients with breast cancer who were receiving regular medical selective estrogen receptor modulator (tamoxifen, n:50), aromatase inhibitors (anastrozole, letrozole, n:50) and gender-matched healthy controls (n:50). Tear functions were measured and compared by the Schirmer test, fluorescein breakup time, corneal staining evaluated by Oxford grading scale and Ocular Surface Disease Index scores.

RESULTS

Mean age was 49.95 (± 9.2), 51.52 (± 7.2) and 51.91 (± 10.3) in tamoxifen, aromatase inhibitors groups and controls (p = 0.426). Mean duration of BC diagnosis (p = 0.536) and drug use (p = 0.417) was not significant between two groups. Ocular Surface Disease Index scores were lower (p < 0.001), and fluorescein breakup time measurements were higher (p < 0.001) in controls. Schirmer test scores were higher in controls than aromatase inhibitors group (p < 0.001). According to the scores of all measurements, the differences between aromatase inhibitors and tamoxifen groups were statistically significant (p < 0.001).

CONCLUSIONS

Our results demonstrated a high difference in all parameters in patients receiving aromatase inhibitors compared to tamoxifen group and controls. Aromatase inhibitors, which reduce estrogen levels in the blood, might affect the tear functions more than tamoxifen, which affects as antiestrogenic on estrogen receptors.

Management of meibomian gland dysfunction: a review

Meibomian gland dysfunction is the leading cause of evaporative dry eye disease and is one of the most common conditions encountered by eye care providers. The disorder is characterized by obstruction of the meibomian gland terminal ducts and/or changes in their glandular secretion, resulting in changes in tear film stability, inflammation, and symptoms of irritation. There is no gold standard treatment for meibomian gland dysfunction, but rather a diversity of options. Conservative measures include warm compresses and lid hygiene, but there is growing interest and need for medical treatments and procedures. Potential medical treatments include antibiotics, nonsteroidal and steroidal anti-inflammatory agents, essential fatty acid supplementation, hormone therapy, and control of Demodex infestation. Procedures include intraductal meibomian gland probing, the use of electronic heating devices, intense pulsed light therapy, and intranasal neurostimulation. We provide an update on meibomian gland dysfunction treatments based on recent studies.

Morphology and Function of Meibomian Glands and Other Tear Film Parameters in Junior High School Students

Purpose:

We measured tear film parameters, including the morphology and function of meibomian glands, in junior high school students at 15 years of age.

Methods:

A total of 111 eyes of 111 students (56 males and 55 females) were enrolled in the study. The ocular symptom score (0–14), after-school study time, lipid layer thickness (LLT) of the tear film, partial blink rate, lid margin abnormalities (0–4), tear film breakup time, corneal and conjunctival epithelial damage (fluorescein staining score, 0–9), meiboscore as determined by noncontact meibography (0–6), Schirmer test value, and meibum grade (0–3) were determined. The relationships between parameters were evaluated with the Spearman correlation coefficient (ρ).

Results:

The meiboscore was 2.8 ± 1.2, and the meibum grade was 1.8 ± 1.2. The meiboscore significantly correlated with the meibum grade (ρ = 0.272, P = 0.004), Schirmer test value (ρ = −0.220, P = 0.021), and LLT (ρ = −0.264, P = 0.005). The breakup time significantly correlated with LLT (ρ = 0.261, P = 0.006), meibum grade (ρ = −0.338, P < 0.001), and fluorescein staining score (ρ = −0.214, P = 0.025). The partial blink rate significantly correlated with the Schirmer test value (ρ = −0.240, P = 0.011). The meiboscore (P < 0.001) and meibum grade (P = 0.032) were significantly greater in males than in females.

Conclusions:

The morphology and function of meibomian glands are altered even at 15 years of age, with the changes being more prominent in males than in females.

TFOS DEWS II Sex, Gender, and Hormones Report

One of the most compelling features of dry eye disease (DED) is that it occurs more frequently in women than men. In fact, the female sex is a significant risk factor for the development of DED. This sex-related difference in DED prevalence is attributed in large part to the effects of sex steroids (e.g. androgens, estrogens), hypothalamic-pituitary hormones, glucocorticoids, insulin, insulin-like growth factor 1 and thyroid hormones, as well as to the sex chromosome complement, sex-specific autosomal factors and epigenetics (e.g. microRNAs). In addition to sex, gender also appears to be a risk factor for DED. "Gender" and "sex" are words that are often used interchangeably, but they have distinct meanings. "Gender" refers to a person's self-representation as a man or woman, whereas "sex" distinguishes males and females based on their biological characteristics. Both gender and sex affect DED risk, presentation of the disease, immune responses, pain, care-seeking behaviors, service utilization, and myriad other facets of eye health. Overall, sex, gender and hormones play a major role in the regulation of ocular surface and adnexal tissues, and in the difference in DED prevalence between women and men. The purpose of this Subcommittee report is to review and critique the nature of this role, as well as to recommend areas for future research to advance our understanding of the interrelationships between sex, gender, hormones and DED.

Meibomian glands, meibum, and meibogenesis

Meibum is a lipid-rich secretion that is produced by fully differentiated meibocytes in the holocrine Meibomian glands (MG) of humans and most mammals. The secretion is a part of a defense mechanism that protects the ocular surface from hazardous environmental factors, and from desiccation. Meibomian lipids that have been identified in meibum are very diverse and unique in nature. The lipid composition of meibum is different from virtually any other lipid pool found in the human body. In fact, meibum is quite different from sebum, which is the closest secretion that is produced by anatomically, physiologically, and biochemically related sebaceous glands. However, meibum of mice have been shown to closely resemble that of humans, implying similar biosynthetic mechanisms in MG of both species. By analyzing available genomic, immunohistochemical, and lipidomic data, we have envisioned a unifying network of enzymatic reactions that are responsible for biosynthesis of meibum, which we call meibogenesis. Our current theory is based on an assumption that most of the biosynthetic reactions of meibogenesis are catalyzed by known enzymes. However, the main features that make meibum unique - the ratio of identified classes of lipids, the extreme length of its components, extensive ω-hydroxylation of fatty acids and alcohols, iso- and anteiso-branching of meibomian lipids (e.g. waxes), and the presence of rather unique complex lipids with several ester bonds - make it possible that either the activity of known enzymes is altered in MG, or some unknown enzymes contribute to the processes of meibogenesis, or both. Studies are in progress to elucidate meibogenesis on molecular level.

Age-related Defects in Ocular and Nasal Mucosal Immune System and the Immunopathology of Dry Eye Disease

Dry eye disease (DED) is a prevalent public health concern that affects up to 30% of adults and is particularly chronic and severe in the elderly. Two interconnected mechanisms cause DED: (1) an age-related dysfunction of lacrimal and meibomian glands, which leads to decreased tear production and/or an increase in tear evaporation; and (2) an age-related uncontrolled inflammation of the surface of the eye triggered by yet-to-be-determined internal immunopathological mechanisms, independent of tear deficiency and evaporation. In this review we summarize current knowledge on animal models that mimic both the severity and chronicity of inflammatory DED and that have been reliably used to provide insights into the immunopathological mechanisms of DED, and we provide an overview of the opportunities and limitations of the rabbit model in investigating the role of both ocular and nasal mucosal immune systems in the immunopathology of inflammatory DED and in testing novel immunotherapies aimed at delaying or reversing the uncontrolled age-related inflammatory DED.

Sex-steroid imbalance in females and dry eye

Dry eye (DE) is a multifactorial disorder of the ocular surface unit that results in eye discomfort, visual disturbance and ocular surface damage. It is one of the most common complaints in daily ophthalmic practice. The risk of DE increases with age in both sexes, while its incidence is higher among females. In addition, the condition of menopause in aging women may also contribute to DE onset or worsening as a consequence of an overall hormonal imbalance. Sex hormones play a key role in ocular surface physiology and they impact differently on ocular surface tissues. Reduced estrogen levels were historically thought to be responsible in age-related DE onset but more recent investigations have reconsidered the role of androgens that are present and exert a protective function on the ocular surface. Hormone levels themselves, withdrawal changes in hormone levels, and the changes in hormone-receptor responsiveness are all important factors but it remains to be fully elucidated how estrogen or androgen insufficiency act alone or together in a combined imbalance or interplay to raise the risk of disease. The purpose of this review is to briefly outline current scientific evidence on the influence of androgens and estrogens, on the Lachrymal and Meibomian glands and on ocular surface epithelia including conjunctival goblet cells during reproductive and menopausal periods. The role of sex steroids is also discussed in relation to the pathogenesis of different forms of DE and Sjogren's syndrome (SS). The impact of systemic hormone therapy (HT) in DE post-menopausal women still appears as a controversial issue, despite the many clinical studies. Finally, the outcomes of topical applications of steroid-based products are summarized, underlying the need for potential (tear) biomarker(s) in the rationale of DE-targeted therapy.

Androgen deficiency and dry eye syndrome in the aging male

PURPOSE

To evaluate the relationship between androgen levels and subjective and objective measures of dry eye syndrome (DES).

METHODS

A total of 263 male patients from the Miami Veterans Affairs Medical Center eye clinic aged ≥50 were recruited for this prospective cross-sectional study. Patients completed Dry Eye Questionnaire 5, underwent tear film evaluation, and had serum androgen levels measured. The correlations between androgen levels, DES composite scores, DES symptoms, and global, lipid, and aqueous tear film parameters were evaluated.

RESULTS

Two hundred sixty-three patients with a mean age of 69 (50-95) were examined. There was no linear association between composite DES scores (generated using latent class analysis) and androgen levels. However, eyes with high DES scores (0.95-1.0) had higher levels of sex hormone-binding globulin (P = 0.03) and lower levels of dehydroepiandrosterone sulfate (DHEAS) (P = 0.02), androstenedione (A) (P = 0.02), and androstane-3α,17β-diol glucuronide (P = 0.03) compared to eyes with intermediate (0.05-0.95) or low (0-0.05) scores. There were no strong correlations between tear film measures and androgen levels. Regarding global parameters, a weak inverse correlation was found between corneal staining and A (r = -0.17, P = 0.009). For lipid parameters, a weak correlation existed between tear breakup time (TBUT) and A (r = 0.15, P = 0.02). When considering aqueous and lipid deficiency independently, the association between TBUT and A existed only with aqueous tear deficiency (r = 0.66, P = 0.002). Regarding aqueous parameters, a weak correlation existed between Schirmer test and DHEAS (r = 0.13, P = 0.047) and A (r = 0.21, P = 0.001).

CONCLUSIONS

There was a weak correlation between higher levels of androstenedione and healthier global, lipid, and aqueous tear film parameters.

Sex hormones and the dry eye

The greater prevalence of dry eye in women compared to men suggests that sex hormones may have a role in this condition. This review aims to present evidence for how sex hormones may affect the ocular structures involved in the production, regulation and maintenance of the normal tear film. It is hypothesised that hormone changes alter the homeostasis of the ocular surface and contribute to dry eye. Androgens impact on the structure and function of the meibomian and lacrimal glands and therefore androgen deficiency is, at least in part, associated with the aetiology of dry eye. In contrast, reports of the effects of oestrogen and progesterone on these ocular structures and on the conjunctiva are contradictory and the mechanisms of action of these female-specific sex hormones in the eye are not well understood. The uncertainty of the effects of oestrogen and progesterone on dry eye symptoms is reflected in the controversial relationship between hormone replacement therapy and the signs and symptoms of dry eye. Current understanding of sex hormone influences on the immune system suggests that oestrogen may modulate a cascade of inflammatory events, which underlie dry eye.

Meibography: A review of techniques and technologies

Meibomian glands play a significant role in tear production by contributing lipids to the superficial tear film.(1) Dysfunction of the meibomian glands destabilizes tears resulting in evaporative dry eye.(2,3) Historically, the meibomian glands were assessed in an ex vivo fashion through histologic studies. However, innovations in ocular imaging have advanced significantly in recent decades to include meibography. Meibography is an imaging study developed 35 years ago exclusively for the purpose of observing the morphology of meibomian glands in vivo.(4,5) In this review of meibography, we briefly describe the etiology of meibomian gland dysfunction and then discuss various meibography techniques, technologies, and methods of image analysis. We close with a review of the literature, crediting various studies for the significant contributions made toward our current understanding of the meibomian glands.

Dry eye syndrome in aromatase inhibitor users

BACKGROUND

Aromatase inhibitors are frequently used as an adjuvant therapy in the treatment of breast cancer. We observed that several patients taking aromatase inhibitors presented with severe dry eye symptoms, and we investigated whether there is a relationship between aromatase inhibitors and dry eyes in these patients.

DESIGN

Retrospective chart review.

PARTICIPANTS

Forty-one women.

METHODS

A computerized search of health records was performed to identify patients using anastrazole, letrozole and exemestane seen by the Cornea Service from August 2008 to March 2011. The results were compared with age-matched controls.

MAIN OUTCOME MEASURES

Ocular surface changes among aromatase inhibitors users.

RESULTS

Of the 41 women, 39 were Caucasians. Thirty-nine patients had breast cancer (95%), one patient had ovarian cancer (2.5%) and one had an unknown primary cancer. Mean age was 68 ± 11.3 years (range 47-95). Most common presenting symptoms were blurred vision in 28 (68%) patients, irritation/foreign body sensation in 12 (29%) patients, redness in 9 (22%) patients, tearing in 6 (22%) patients and photosensitivity in 2 (5%) patients. Mean Schirmer's test measurement was 11 ± 5.8 mm (range 0.5-20 mm). Blepharitis was noted in 68 of 82 eyes (73%), decreased or poor tear function in 24 eyes (29%), conjunctival injection in 18 eyes (22%) and superficial punctate keratitis in 12 eyes (29%). Among an age-matched population (45-95 years), dry eye syndrome was found in only 9.5% of patients.

CONCLUSIONS

Because the prevalence of ocular surface disease signs and symptoms appears to be higher in study group than control patients, aromatase inhibitors might be a contributing factor to the dry eye symptoms.

Aging and dry eye disease

Dry eye disease is a prevalent eye disorder that in particular affects the elderly population. One of the major causes of dry eye, meibomian gland dysfunction (MGD), shows increased prevalence with aging. MGD is caused by hyperkeratinization of the ductal epithelium of meibomian gland and reduced quantity and/or quality of meibum, the holocrine product that stabilizes and prevents the evaporation of the tear film. Of note, retinoids which are used in current anti-aging cosmetics may promote the development of MGD and dry eye disease. In this review, we will discuss the possible mechanisms of age-related MGD.

Ocular surface disease and quality of life in patients with glaucoma

PURPOSE

To investigate the relationship between ocular surface disease and glaucoma-related quality of life (QoL), glaucoma severity, and treatment in patients with open-angle glaucoma.

DESIGN

Cross-sectional study.

METHODS

SETTING

Clinical practice.

STUDY POPULATION

One hundred twenty-four participants-patients with mild (n = 48), moderate (n = 34), or severe (n = 19) glaucoma and 23 controls (glaucoma suspects) not receiving glaucoma treatment-were enrolled. Severity was stratified according to binocular visual field loss. OBSERVED PROCEDURES: Demographic information, the Ocular Surface Disease Index (OSDI), and Glaucoma Quality of Life-15 (GQL-15) questionnaires were administered.

MAIN OUTCOME MEASURES

OSDI score, GQL-15 score, number and type of glaucoma medications, daily dose of benzalkonium chloride (BAK), and visual field indices.

RESULTS

OSDI scores and the number of patients with OSD increased with increasing glaucoma severity (P < .001 and P < .005). GQL-15 scores reflected decreased QoL with increasing glaucoma severity (P < .001). These trends were maintained after sub-stratification for age and sex. On univariate regression OSDI was significantly correlated with GQL-15 summary score, glaucoma severity, multiple topical glaucoma medications, worse eye mean deviation and pattern standard deviation, use of topical beta blockers, topical carbonic anhydrase inhibitors, daily dose of BAK, and glaucoma filtration surgery. On multivariate regression GQL-15 summary score (odds ratio [OR] 4.14, 95% confidence interval [CI] 2.59-6.63, P < .001) and a daily dose of BAK greater than 3 (OR 2.47, 95% CI 1.17-5.21, P = .018) were predictive of OSDI score.

CONCLUSIONS

OSD is more common in patients with increasing glaucoma severity and is associated with poorer glaucoma-related QoL and higher exposure to BAK.

Age-related changes in the meibomian gland

The purpose of this study was to characterize the age-related changes of the mouse meibomian gland. Eyelids from adult C57Bl/6 mice at 2, 6, 12 and 24 months of age were stained with specific antibodies against peroxisome proliferator activated receptor gamma (PPARgamma) to identify differentiating meibocytes, Oil Red O (ORO) to identify lipid, Ki67 nuclear antigen to identify cycling cells, B-lymphocyte-induced maturation protein-1 (Blimp1) to identify potential stem cells and CD45 to identify immune cells. Meibomian glands from younger mice (2 and 6 months) showed cytoplasmic and perinuclear staining with anti-PPARgamma antibodies with abundant ORO staining of small, intracellular lipid droplets. Meibomian glands from older mice (12 and 24 months) showed only nuclear PPARgamma localization with less ORO staining and significantly reduced acinar tissue (p < 0.04). Acini of older mice also showed significantly reduced (p < 0.004) numbers of Ki67 stained nuclei. While Blimp1 appeared to diffusely stain the superficial ductal epithelium, isolated cells were occasionally stained within the meibomian gland duct and acini of older mice that also stained with CD45 antibodies, suggesting the presence of infiltrating plasmacytoid cells. These findings suggest that there is altered PPARgamma receptor signaling in older mice that may underlie changes in cell cycle entry/proliferation, lipid synthesis and gland atrophy during aging. These results are consistent with the hypothesis that mouse meibomian glands undergo age-related changes similar to those identified in humans and may be used as a model for age-related meibomian gland dysfunction.

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.

Research in Dry Eye: Report of the Research Subcommittee of the International Dry Eye WorkShop (2007)

Members of the DEWS Research Subcommittee reviewed research into the basic mechanisms underlying dry eye disease. Evidence was evaluated concerning the tear film, lacrimal gland and accessory lacrimal glands, ocular surface epithelia (including cornea and conjunctiva), meibomian glands, lacrimal duct system and the immune system. Consideration was given to both animal and human research data. Results are presented as a series of information matrices, identifying what is known and providing supporting references. An attempt is made to identify areas for further investigation.

The Epidemiology of Dry Eye Disease: Report of the Epidemiology Subcommittee of the International Dry Eye WorkShop (2007)

The report of the Epidemiology Subcommittee of the 2007 Dry Eye WorkShop summarizes current knowledge on the epidemiology of dry eye disease, providing prevalence and incidence data from various populations. It stresses the need to expand epidemiological studies to additional geographic regions, to incorporate multiple races and ethnicities in future studies, and to build a consensus on dry eye diagnostic criteria for epidemiological studies. Recommendations are made regarding several characteristics of dry eye questionnaires that might be suitable for use in epidemiological studies and randomized controlled clinical trials. Risk factors for dry eye and morbidity of the disease are identified, and the impact of dry eye disease on quality of life and visual function are outlined. Suggestions are made for further prospective research that would lead to improvement of both eye and general public health.

Impact of dry eye syndrome on vision-related quality of life

PURPOSE

To evaluate the impact of dry eye syndrome (DES) on vision-associated quality of life.

DESIGN

Cross-sectional study.

METHODS

We identified 450 participants in the Women's Health Study (WHS) and 240 participants in the Physicians' Health Study (PHS) and sent a supplementary questionnaire asking how much their everyday activities were limited by symptoms of dry eye and to what degree problems with their eyes limited them in reading, driving, working at the computer, their professional activity, and watching television. By design, one-third of study subjects had clinically diagnosed DES or severe symptoms and two-thirds did not. We used logistic regression to examine relationships of DES with reported problems with everyday activities in each cohort and pooled estimates using meta-analysis methods.

RESULTS

Of the participants invited, 85% completed the supplementary questionnaire, including 135 WHS and 55 PHS participants with DES, and 250 WHS and 149 PHS participants without DES. Controlling for age, diabetes, hypertension, and other factors, those with DES were more likely to report problems with reading ([odds ratio] OR = 3.64, 95% [confidence interval] CI 2.45 to 5.40, P < .0001); carrying out professional work (OR = 3.49, 95% CI 1.72 to 7.09, P= 0.001); using a computer (OR = 3.37, 95% CI 2.11 to 5.38, P < .0001); watching television (OR = 2.84, 95% CI 1.05 to 7.74, P = .04); driving during the day (OR = 2.80, 95% CI 1.58 to 4.96, P < .0001); and driving at night (OR = 2.20, 95% CI 1.48 to 3.28, P < .0001).

CONCLUSIONS

DES is associated with a measurable adverse impact on several common and important tasks of daily living, further implicating this condition as an important public health problem deserving increased attention and resources.

Smoking associated with damage to the lipid layer of the ocular surface

PURPOSE

To evaluate the effects of smoking on ocular surface.

DESIGN

Prospective, comparative, interventional case series.

METHODS

setting: Institutional. study population: Sixty smokers (33 men, 27 women) and 34 healthy subjects (18 men, 16 women) were enrolled into this study. Patients with associated ophthalmic or systemic diseases, and history of contact lens use and ocular surgery were excluded. The duration of average smoking was 13.1 years (range 5 to 35 years).

INTERVENTION

Ocular surface was evaluated by measuring corneal and conjunctival sensitivity, surface staining with fluorescein, tear film breakup time, Schirmer 1 test, and conjunctival impression cytology. Dry eye symptoms were scored by questionnaire. Kinetic analysis of sequential tear interference images obtained by a DR-1 tear lipid layer interferometry was used to investigate the precorneal lipid layer spread. Results were compared with a control group.

MAIN OUTCOME MEASURES

Comparison of subjective complaints with objective parameters in cigarette smokers and normal subjects.

RESULTS

In the smoker group, the mean Schirmer 1 test value was 10.8 mm (range 8 to 14 mm). The mean breakup time was 5.3 seconds (range 1 to 10 seconds), the average conjunctival sensitivity was 26.2 mm (range 0 to 45 mm), and the average central corneal sensitivity was 37.6 mm (range 5 to 60 mm). There was no statistically significant difference in goblet cell densities or in Schirmer 1 test values between smokers and controls (P > .05). Higher grades of lipid layer changes were observed in smokers by DR-1 interferometry kinetic analysis.

CONCLUSIONS

Smoking has deteriorating effects on the lipid layer of precorneal tear film.

Androgen regulation of lipogenic pathways in the mouse meibomian gland

We hypothesize that androgens regulate lipogenesis in the meibomian gland. To test this hypothesis, we sought to determine whether androgens increase the mRNA levels of key lipogenic enzymes involved in the synthesis of cholesterol and fatty acids. In addition, we examined whether androgens stimulate the expression of genes for sterol regulatory element binding proteins (SREBP) 1 and 2, which are transcription factors that play an important role in the coordinate regulation of lipogenic enzymes. Meibomian glands were obtained from castrated mice, that were treated with vehicle or testosterone for 2 weeks. Tissues were processed for the analysis of selected mRNAs by real-time PCR. Our results show that testosterone increases the mRNA levels of critical lipogenic enzymes, including those related to ATP-citrate lyase, acetyl-CoA-synthase, acetyl-CoA-carboxylase, acetoacetyl-CoA-synthase and 3-hydroxy-3-methylglutaryl CoA synthase 1. Our findings also demonstrate that androgens upregulate the expression of genes encoding the transcription factors SREBPs 1 and 2. Our results indicate that androgens may control multiple aspects of lipogenesis in the meibomian gland.

New Insights into the Diagnosis and Treatment of Dry Eye

Over the past decade, numerous advances have been made in relation to dry eye diagnostic markers, technologies, and treatment options. The mainstay of treatment of dry eye is the use of artificial tear solutions and punctum plugs. A goal is the development of agents that provide symptomatic treatment and, at the same time, improve ocular surface keratinization. It is the authors' opinion that the functional visual acuity tester and the new tear stability analysis system will be widely used to improve diagnosis and evaluate treatment outcomes in KCS. Advances in treatment will utilize anti-inflammatory agents, immune suppressants such as Cyclosporin A and FK-506, growth hormones, androgens, topical mucins and ocular surface stimulating drugs, like INS365. Although aqueous-deficient dry eye is most commonly not associated with Sjogren syndrome (SS), aqueous-deficient dry eye is often most severe in patients with SS; thus, this article focuses mainly on SS-associated dry eye.

Is complete androgen insensitivity syndrome associated with alterations in the meibomian gland and ocular surface?

PURPOSE

This study's purpose was to determine whether complete androgen insensitivity syndrome (CAIS) is associated with alterations in the meibomian gland and ocular surface.

METHODS

Individuals with CAIS, as well as age-matched female and male controls, completed questionnaires which assessed dry eye symptoms and underwent slit lamp evaluations of the tear film, tear meniscus, lids and lid margins and conjunctiva. The quality of meibomian gland secretions was also analyzed.

RESULTS

Our results demonstrate that CAIS is associated with meibomian gland alterations and a significant increase in dry eye signs and symptoms. Clinical assessment revealed that CAIS women, as compared to controls, had a significant increase in telangiectasia, keratinization, lid erythema and orifice metaplasia of the meibomian glands, and a significant decrease in the tear meniscus and quality of meibomian gland secretions. Questionnaire results showed that dry eye symptoms were increased over twofold in CAIS individuals, as compared to controls, including a significant increase in the sensations of dryness, pain and light sensitivity.

CONCLUSION

Our results suggest that androgen insensitivity may promote meibomian gland dysfunction and an increase in the signs and symptoms of dry eye.

Androgen deficiency, Meibomian gland dysfunction, and evaporative dry eye

OBJECTIVE

We have recently discovered that women with primary and secondary Sjögren's syndrome are androgen-deficient. We hypothesize that this hormone insufficiency contributes to the meibomian gland dysfunction, tear film instability, and evaporative dry eye that are characteristic of this autoimmune disorder. If our hypothesis is correct, we predict: (1) that androgens regulate meibomian gland function, control the quality and/or quantity of lipids produced by this tissue, and promote the formation of the tear film's lipid layer; and (2) that androgen deficiency, due to an attenuation in androgen synthesis (e.g., during Sjögren's syndrome, menopause, aging, complete androgen-insensitivity syndrome [CAIS] and anti-androgen use), will lead to meibomian gland dysfunction and evaporative dry eye. The following studies were designed to test these predictions.

METHODS

Experimental procedures included clinical studies, animal models, and histological, biochemical, molecular biological, and biomedical engineering techniques.

RESULTS

Our results demonstrate that: (1) androgens regulate the meibomian gland. This tissue contains androgen receptor mRNA, androgen receptor protein within acinar epithelial cell nuclei, and Types 1 and 2 5alpha-reductase mRNAs. Moreover, androgens appear to modulate lipid production and gene expression in mouse and/or rabbit meibomian glands; and (2) androgen deficiency may lead to meibomian gland dysfunction, altered lipid profiles in meibomian gland secretions, tear film instability, and evaporative dry eye. Thus, we have found that anti-androgen therapy in men is associated with meibomian gland disease, a decreased tear film breakup time, and functional dry eye. Furthermore, we have discovered that androgen receptor dysfunction in women with CAIS is associated with meibomian gland changes and a significant increase in the signs and symptoms of dry eye. Of interest, we have also found that androgen deficiency is associated with significant and striking alterations in the neutral and polar lipid patterns of human meibomian gland secretions.

CONCLUSIONS

Our findings show that the meibomian gland is an androgen target organ and that androgen deficiency may promote meibomian gland dysfunction and evaporative dry eye. Overall, these results support our hypothesis that androgen deficiency may be an important etiologic factor in the pathogenesis of evaporative dry eye in women with Sjögren's syndrome.