Evaluation of Ocular Surface Health in Patients with Obstructive Sleep Apnea Syndrome

Chronic intermittent hypoxia modulates corneal fibrotic markers and inflammatory cytokine expression in a sex-dependent manner

Chronic intermittent hypoxia (CIH) is a commonly observed condition in patients suffering from obstructive sleep apnea (OSA). Previous studies link CIH to fibrosis, inflammation, and hormonal dysregulation across various tissues. Yet, the effect of CIH in the cornea is unknown. Moreover, women and men diagnosed with OSA present with diverse symptoms, suggesting sex-specific pathophysiology at play. Thus, we used a rat model to assess the impact of CIH and sex on protein expression of corneal fibrotic markers (α-SMA, COL III, cFN, TSP-1), proinflammatory cytokines (IL-1 α, IL-17, IL-18, and IFN-γ), and hormone receptors (ERα, ERβ, GPER, GnRH-R, and LH-R). Male and female Sprague Dawley rats were exposed to normoxic or CIH conditions during their sleep cycle for 14 days. Extracted corneal proteins were subjected to Western blot and multiplex magnetic bead analysis. Our results reveal sex differences in fibrotic and inflammatory markers in the cornea, whereby female corneas exhibit higher levels of fibrotic markers, while male corneas exhibit increased inflammatory cytokines. CIH exposure resulted in elevated levels of α-SMA and pro-inflammatory cytokines in female corneas, while there was no impact on fibrotic or inflammatory markers in male corneas. Additionally, CIH exposure reduced hormone receptors in male and female corneas in a sex-dependent manner. Correlation analyses identified associations of corneal hormone receptors with corneal fibrotic and pro-inflammatory markers that were dependent on sex, with female corneas demonstrating stronger correlations compared to male corneas. Altogether, our data suggests hormone-mediated signaling may contribute to CIH-mediated corneal fibrosis and inflammatory phenotypes, especially in females.

Could Nocturnal Chronic Hypoxia Cause Ocular Surface Symptoms by Affecting Limbal Epithelial Cells in Patients With Obstructive Sleep Apnea?

PURPOSE

To investigate the effect of nocturnal chronic hypoxia on the thickness changes of the corneal limbal epithelial area that provides regeneration of the corneal epithelium and ocular surface evaluation parameters in patients with obstructive sleep apnea (OSA).

METHODS

All patients diagnosed with OSA and the control group underwent a complete ophthalmological examination, including slit-lamp examination and funduscopy. Tear break-up time, Schirmer test-I, Ocular Surface Disease Index Questionnaire, and anterior segment optical coherence tomography were performed with fluorescein sterile strip for ocular surface evaluation.

RESULTS

Oxygenation levels of patients during night sleep were different between mild-severe and moderate-severe groups. The Ocular Surface Disease Index results were statistically significantly different between the severe OSA group and the mild OSA group, and between the control group and all other OSA groups (P < 0.05). The limbal epithelial thickness (LET) value was found to be lower in the moderate OSA group than in the mild OSA group and the control group and was statistically significantly higher than in the severe OSA group. In the severe OSA group, the LET value was found to be statistically significantly lower than all other groups (P < 0.05).

CONCLUSIONS

In the literature, there is no study evaluating the effect of prolonged hypoxia on limbus epithelium as in patients with OSA. In this study, LET was measured to be statistically significantly thinner as the severity of OSA increased. Considering these results, it can be concluded that the proliferation of limbal stem cells is reduced in prolonged hypoxia.

Impact of Obstructive Sleep Apnea and Continuous Positive Airway Pressure Treatment on Dry Eye Disease: A Systematic Review and Meta-Analysis

Obstructive sleep apnea (OSA) has been reported to influence the ocular surface and may lead to dry eye disease (DED). Continuous positive airway pressure (CPAP) is the first-line conservative treatment for OSA. However, CPAP might also have mask-related side effects that could deteriorate DED simultaneously. This study investigated the impact of OSA on DED (Aim 1), and CPAP on DED (Aim 2). Five databases were searched for articles published up to May, 2024. OSA severity, CPAP usage, and DED parameters, including tear breakup time (TBUT), Schirmer test, Ocular Surface Disease Index (OSDI), and Corneal Fluorescence Staining Score (CFS), were analyzed. For Aim 1, the random-effects model was used for meta-analysis, and the leave-one-out method was used for sensitivity analysis. For Aim 2, a narrative synthesis with critical appraisal of the literature was performed. Eleven studies with 1,526 patients for Aim 1 and three studies with 180 patients for Aim 2 were included. For Aim 1, OSA patients had poorer dry eye profiles of TBUT, Schirmer test, and OSDI when compared to non-OSA patients. For Aim 2, it seemed that those wearing CPAP for less than half a year did not have enough improvement in dry eye status. Instead, those wearing CPAP for at least a year reached greater therapeutic effects for OSA and DED. We concluded that OSA patients may suffer from poorer dry eye condition compared to non-OSA patients. Besides, wearing CPAP for long enough duration (at least 1 year) seemed to have better improvement in DED.

Associations Between Obstructive Sleep Apnea Syndrome, Dry Eye Disease, and CPAP Usage Among Taiwanese Patients: A Retrospective Analysis

Study Objectives

To evaluate the association between obstructive sleep apnea (OSA) and dry eye disease (DED) and analyze the impact of Continuous Positive Airway Pressure (CPAP) on DED.

Methods

This is a retrospective population-based case-control study. Patients who underwent polysomnography in Taiwan from March 1, 2009, to March 1, 2020, were identified from the database of a sleep center. Patients who were diagnosed with keratoconjunctivitis sicca or tear film insufficiency were included. Patients without data from Schirmer's test, lacking tear break-up time values, or with a history of refractive surgery, Sjögren's syndrome, ocular injuries, or a disability in eyelid closure were excluded. All patients with DED enrolled had DED in both eyes. OSA severity between patients with and without DED was compared.

Results

In total, 86 patients with DED and 86 age-matched patients without DED were enrolled. Significant differences in apnea-hypopnea index values (patients with DED: 29.1 ± 23.4, patients without DED: 17.9 ± 20.2, P < 0.001), OSA severity (P < 0.001), and lowest oxygen saturation (P = 0.040) between patients with and without DED were observed. A multivariate logistic regression model indicated that the use of CPAP was independently associated with DED after adjustments for OSA severity. Patients undergoing CPAP were at greater risk of developing DED than those not undergoing CPAP (Odds ratio: 3.93, 95% confidence interval: 1.47-10.49, P = 0.006).

Conclusion

OSA severity is associated with DED and might be attributed to the use of CPAP.

Dry eye in mind: Exploring the relationship between sleep and ocular surface diseases

PURPOSE

Dry Eye Disease (DED) is regarded as the most common ocular surface disease worldwide, entailing symptoms that have a major impact on the physical and psychological well-being of DED patients. In this context, the impact of sleep quality on DED has recently attracted attention. Indeed, although little is known about the mechanisms underlying the relationship between sleep and ocular surface diseases, recent evidence suggests that a reciprocal relationship exists between sleep quality and DED. Aim of the study was to investigate such relationship by means of both survey-based and instrumental analysis in a large population.

PATIENTS AND METHODS

The present cross-sectional study included 1182 DED patients who completed the Insomnia Severity Index (ISI) and the Ocular Surface Disease Index (OSDI) questionnaires. Moreover, tear break-up time (TBUT) and ocular surface staining (OSS) data of included patients were collected by physicians.

RESULTS

According to the findings of this study, in DED patients, the severity of dry eye symptoms and signs, assessed by OSDI score, TBUT, and ocular surface staining, is associated with more severe insomnia symptoms. Furthermore, higher severity of DED symptoms seems to be associated with the occurrence of nocturnal awakenings rather than with problems in falling asleep.

CONCLUSIONS

Present work contributes to the understanding of the complex relationship between DED and insomnia by showing that in a large population of DED patients, the more severe the insomnia, the more severe the DED symptoms and signs.

Effect of chronic intermittent hypoxia on ocular and intraoral mechanical allodynia mediated via the calcitonin gene-related peptide in a rat

STUDY OBJECTIVES

Obstructive sleep apnea, a significant hypoxic condition, may exacerbate several orofacial pain conditions. The study aims to define the involvement of calcitonin gene-related peptide (CGRP) in peripheral and central sensitization and in evoking orofacial mechanical allodynia under chronic intermittent hypoxia (CIH).

METHODS

Male rats were exposed to CIH. Orofacial mechanical allodynia was assessed using the eyeblink test and the two-bottle preference drinking test. The CGRP-immunoreactive neurons in the trigeminal ganglion (TG), CGRP-positive primary afferents projecting to laminae I-II of the trigeminal spinal subnucleus caudalis (Vc), and neural responses in the second-order neurons of the Vc were determined by immunohistochemistry. CGRP receptor antagonist was administrated in the TG.

RESULTS

CIH-induced ocular and intraoral mechanical allodynia. CGRP-immunoreactive neurons and activated satellite glial cells (SGCs) were significantly increased in the TG and the number of cFos-immunoreactive cells in laminae I-II of the Vc were significantly higher in CIH rats compared to normoxic rats. Local administration of the CGRP receptor antagonist in the TG of CIH rats attenuated orofacial mechanical allodynia; the number of CGRP-immunoreactive neurons and activated SGCs in the TG, and the density of CGRP-positive primary afferent terminals and the number of cFos-immunoreactive cells in laminae I-II of the Vc were significantly lower compared to vehicle-administrated CIH rats.

CONCLUSIONS

An increase in CGRP in the TG induced by CIH, as well as orofacial mechanical allodynia and central sensitization of second-order neurons in the Vc, supported the notion that CGRP plays a critical role in CIH-induced orofacial mechanical allodynia.

Ocular Surface Assessment in Patients with Obstructive Sleep Apnea Syndrome

Purpose

To evaluate the prevalence of dry eye, meibomian gland dysfunction (MGD), and conjunctivochalasis in patients with obstructive sleep apnea (OSA).

Methods

We included 37 patients diagnosed with OSA according to polysomnography. The control group comprised 31 subjects. The study participants underwent a complete ophthalmic examination and ocular surface assessment. Meibography was done using infrared imaging. Furthermore, tear meniscus height was measured using anterior segment optical coherence tomography.

Results

The mean age of the OSA and control groups were 50.3 ± 9.0 and 50.3 ± 8.0, respectively (P = 0.77). The mean scale for meibomian gland expression, meibomian gland plugging, and lid margin telangiectasia was similar in both groups. The meiboscores of the upper and lower eyelids were similar in both groups (upper meiboscores of 0.67 ± 0.48 and 0.37 ± 0.49 in OSA and control group, P = 0.180 and lower meiboscores of were 0.47 ± 0.57 and 0.22 ± 0.42 in OSA and control group, P = 0.179). The mean tear break-up time (TBUT) was significantly lower in the OSA group (8.17 ± 3.70 compared to 11.47 ± 4.52, P < 0.001). Upper and lower tear meniscus height were 186.14 ± 40.11 μm and 199.59 ± 37.22 μm and 237.25 ± 82.86 μm and 218.59 ± 68.8 μm in OSA and control group, respectively (P = 0.221, P = 0.166). The mean conjunctivochalasis grading score was 0.92 ± 0.72 and 0.81 ± 0.65 in the OSA and control groups, respectively (P = 0.143).

Conclusions

Despite decreased TBUT in patients with OSA, other dry eye parameters are not altered in these patients. Moreover, the frequency of MGD and conjunctivochalasis is not higher in OSA patients.

Real Life Impact of Dry Eye Disease

Dry Eye Disease (DED) is an increasingly common condition that affects between 5% and 50% of the global population. Even though DED is most frequently diagnosed in older people, it has also been diagnosed in young adults and adolescents more frequently in recent years (employees, gamers). People can experience different types of symptoms and find it challenging to read, watch TV, cook, climb stairs, and meet friends. Mild and severe dry eye can reduce quality of life similarly to mild psoriasis and moderate-to-severe angina. Furthermore, DED patients experience serious difficulties driving vehicles, especially at night, and show a decrease in work productivity, which, when combined with the relevant indirect cost that this condition produces, poses a serious challenge in our days. In addition, DED patients are more likely to develop depression and suicidal ideations and experience frequent sleep disorders. Finally, it is discussed how lifestyle changes, such as increased physical activity, blinking exercises, and a proper diet, have positive implications for the management of this condition. Our aim is to draw attention to the negative effects of dry eye in real life, which are unique to each patient, especially as they relate to the non-visual symptoms experienced by DED patients.

Ocular manifestations in COVID-19 infections: a case series

Introduction

The prevalence of ocular abnormalities of COVID-19 is different according to different reports. However, currently available evidence on the presence of this virus in ocular secretions and its association with conjunctivitis is not well established.

Objective

To reveal the ocular features among COVID-19 patients and to describe them with the findings of clinical data, inflammatory markers, and respiratory support therapy.

Methods

Ocular symptoms were evaluated and recorded in 494 COV19 patients through questionnaire-style interviews, and an ophthalmologic examination. Data including age, sex, disease severity, and nasopharyngeal swab results were collected. Laboratory test values were reviewed. Patients with COVID-19 infections were classified into severe cases and mild cases.

Results

The prevalence of ocular features was (2.83%). The most common features were conjunctival hyperaemia, epiphora, and foreign body sensation with itching. Patients with ocular manifestations on CPAP support therapy had higher rates of itching, lower rates of foreign body sensation. No differences were found in the levels of inflammatory marker. Meanwhile, patients used respiratory-aid therapy revealed higher values of white blood cells, platelet counts, erythrocyte sedimentation rate, C-reactive protein, ferritin, and lactate dehydrogenase.

Discussion

Ocular involvement in COVID-19 and possibility of disease transmission through ocular tissues and secretions, has been registered in some reports, with a prevalence of 2-32%. The external and internal ocular parts are involved.

Conclusion

Ocular features are not infrequent in COVID-19 patients.

Alterations of ocular surface parameters in patients with obstructive sleep apnea syndrome

Purpose

This study aimed to evaluate changes in ocular surface parameters among obstructive sleep apnea syndrome (OSAS) patients.

Methods

44 healthy volunteers (88 eyes) and 27 OSAS patients (54 eyes) were recruited in our cross-sectional study. 14 patients were classified as mild&moderate OSAS, and 13 patients were classified as severe OSAS. For evaluating the ocular surface, the following tests were conducted: the height of tear meniscus (TMH), first non-invasive tear break-up time (FNITBUT), mean non-invasive tear break-up time (MNITBUT), the score of Meibomian gland dropout area (Meiboscore), the tear test of anesthesia-free Schirmer I (SIT), corneal fluorescein staining (CFS), partial blinks rate (PBR), the lipid layer thickness (LLT), ocular surface disease index (OSDI). The results obtained from the study were analyzed and compared among the groups.

Results

FNITBUT, MNITBUT, and TMH were lower. OSDI, CFS, Meiboscore and PBR were higher in the OSAS group than those in the control group. The mild&moderate as well as the severe OSAS subgroups had statistically significantly lower TMH, and higher OSDI and PBR than the control group. Meanwhile, we found there were no significant differences between two OSAS subgroups. CFS was higher in the severe OSAS group than the mild&moderate OSAS group. Significantly lower FNITBUT, MNITBUT and higher Meiboscore were observed in the severe OSAS subgroup than in the control group, and MNITBUT was higher in severe OSAS objects than in the mild&moderate OSAS objects. LLT and SIT did not exhibit significant differences among control and OSAS subgroups. FNITBUT and MNITBUT showed significantly negative correlations with BMI, while Meiboscore showed a significant positive correlation with AHI.

Conclusion

Patients with OSAS have a tendence of dry eyes, whereas control subjects do not. This indicates us that the OSAS patients should pay more attention to ocular surface care.

Comparison of ocular surface assessment outcomes between healthy controls and patients with obstructive sleep apnea-hypopnea syndrome: a meta-analysis of the literature

Objective: This meta-analysis aims to determine whether ocular surface alterations are associated with disease severity in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS). Methods: The protocol for this systematic review and meta-analysis was registered in PROSPERO. We conducted the search in six electronic databases (China National Knowledge Infrastructure, EMBASE, Cochrane Library, Web of Science, Wanfang, and PubMed) from since the construction of the databases to 30 December 2022. The standard mean difference (SMD) and correlation coefficients are reported as measures of the effect size in the presence of retrieved data. In addition, the random effects model or fixed effects model was used in a combined analysis. Stata 11.0 and R 3.6.1 were used for statistical analyses of the data. Results: A total of 15 studies satisfied the inclusion criteria for this study. The prevalence of floppy eyelid syndrome (FES) and dry eye syndrome in patients with obstructive sleep apnea-hypopnea syndrome was 40 and 48%, respectively. In addition, the Schirmer 1 value and tear break-up time (TBUT) were remarkably reduced in patients with OSAHS when compared to that of the controls. The ocular surface disease index (OSDI) scores, Oxford corneal staining scores, and the rates of loss in the meibomian glands were elevated in patients with obstructive sleep apnea-hypopnea syndrome when compared to that of the controls, especially those with severe disease. Moreover, the Schirmer 1 value and tear break-up time exhibited a negative correlation with the apnea-hypopnea index (AHI), and the OSDI showed a positive association with the apnea-hypopnea index. Conclusion: Patients with OSAHS had a greater prevalence of FES than the healthy controls. They also showed lower Schirmer 1 value and tear break-up time but had a higher OSDI, Oxford corneal staining scores, and rates of loss in the meibomian glands than the healthy controls. Clinical Trial Registration: (https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=392527).

Ocular manifestations of common pulmonary diseases: a narrative review

Several pulmonary disorders can cause ocular involvement. Understanding these manifestations is critical for early diagnosis and treatment. Hence, we set out to examine the most common ocular manifestations of asthma, chronic obstructive pulmonary disease (COPD), sarcoidosis, obstructive sleep apnea (OSA), and lung cancer. Allergic keratoconjunctivitis and dry eye are two ocular manifestations of bronchial asthma. The inhaled corticosteroids used to treat asthma can cause cataract formation. COPD is associated with ocular microvascular changes as a result of chronic hypoxia and systemic inflammation spillover into the eyes. Its clinical significance, however, is unknown. Ocular involvement is common in sarcoidosis, occurring in 20% of cases of pulmonary sarcoidosis. It can affect nearly any anatomical structure of the eye. Obstructive sleep apnea has been linked to floppy eye syndrome, glaucoma, non-arteritic anterior ischemic optic neuropathy, keratoconus, retinal vein occlusion, and central serous retinopathy, according to research. However, while an association has been established, causality has yet to be established. The effect of positive airway pressure (PAP) therapy used to treat OSA on the aforementioned ocular conditions is unknown. PAP therapy can cause eye irritation and dryness. Lung cancer can affect the eyes through direct nerve invasion, ocular metastasis, or as part of a paraneoplastic syndrome. The goal of this narrative review is to raise awareness about the link between ocular and pulmonary disorders in order to aid in the early detection and treatment of these conditions.

Evaluation of the Ocular Surface and Meibomian Gland in Obstructive Sleep Apnea Hypopnea Syndrome

Purpose

To assess the ocular surface and meibomian gland (MG) of patients with obstructive sleep apnea hypopnea syndrome (OSAHS) and to explore the effects of surgery for OSAHS on the ocular surface and MG.

Methods

Based on the apnea hypopnea index (AHI), 21 patients with mild OSAHS (Group A, 5/h ≤ AHI < 15/h), 20 patients with moderate OSAHS (Group B, 15/h ≤ AHI < 30/h), 62 patients with severe OSAHS (Group C, AHI ≥ 30/h) were examined. The ocular surface and MG were evaluated using Keratograph 5M. In addition, detailed Ophthalmic examination including visual acuity, refraction, slit-lamp examination of the anterior segment, corneal fluorescein staining (CFS), ocular surface disease index (OSDI) scoring, Schirmer I test (SIT) and serum lipid measurement was performed. For OSAHS patients with dry eye syndrome (DES) who underwent uvulopalatopharyngoplasty for improving AHI, the conditions of the ocular surface and MG were compared before surgery and 3 months after surgery. Only the data of the right eyes were analyzed.

Results

There were no significantly different in the OSDI score, tear meniscus height (TMH), or loss ratio of the lower eyelid (LRLE) among these groups. The first non-invasive tear film breakup time (fNIBUT), average non-invasive tear film breakup time (avNIBUT), bulbar redness index (BRI), lipid layer grading (LLG), CFS, plugged orifices and distortion in MG, the loss ratio of upper eyelid (LRUE), and the incidence of DES, floppy eyelid syndrome (FES) and meibomian gland dysfunction (MGD) showed significant differences between Groups A and C (p = 0.015, p = 0.018, p < 0.001, p = 0.022, p = 0.036, p = 0.007, p = 0.019, p = 0.017, p = 0.045, p = 0.013, and p = 0.029, respectively). The SIT in the Group A was significantly higher than in Group B (p = 0.025) and in Group C (p < 0.001). In the correlation analyses, the fNIBUT, avNIBUT, SIT and LLG had negative correlations with the AHI (p = 0.013, p = 0.010, p = 0.003, p < 0.001, and p = 0.006, respectively). The BRI, CFS and LRUE were positively correlated with the AHI (p = 0.006, p = 0.007, and p = 0.046, respectively). Three months after surgery, there were no significant differences in the ocular surface or MG.

Conclusion

Patients with severe OSAHS have poor stability of tear film and are prone to lipid-deficient dry eye as a result of the loss of meibomian gland. By improving the AHI, the ocular surface damage of OSAHS patients cannot be reversed in a short time.

The Association Between Dry Eye and Sleep Quality Among the Adult Population of Saudi Arabia

Background and objective

Dry eye disease (DED) is one of the most prevalent ocular diseases worldwide. DED symptoms can result from disturbances to the homeostasis of the middle tear film layer (aqueous layer), including inflammation, pain, and eye discomfort, which can have a negative impact on individuals’ quality of life and daily activities. Sleep disorders are highly prevalent among patients with DED, and the incidence of sleep disturbances in DED patients has been reported to be as high as 40%. Decreased sleep quality can aggravate dry eye symptoms by increasing tear osmolarity and decreasing tear production. In this study, we aimed to investigate the association between DED and sleep quality in the adult population of Saudi Arabia.

Methods

This cross-sectional study was conducted among adult patients aged 18 years and above in Saudi Arabia in August 2021. A validated Arabic version of the Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality, and the Ocular Surface Disease Index (OSDI) questionnaire was employed to diagnose DED. Data collection and analysis were performed using the SPSS Statistics software (IBM, Armonk, NY).

Results

A total of 234 subjects were analyzed, and 59.8% of the participants were women. Our tool suggested that 71.4% of the included participants had severe DED, 15% had moderate DED, and 13.7% had mild DED. However, 40.6% of the participants reported that they had not been diagnosed with DED previously and 34.6% had no previous DED symptoms. The mean total PSQI score was 8.63 ±2.23, with the highest score recorded for component 2: sleep latency (1.73) and the lowest score recorded for component 4: habitual sleep efficiency (0.20). Poor sleep quality as assessed by PSQI showed a significant positive correlation with the severity of DED as assessed by OSDI.

Conclusion

The significant positive correlation between poor sleep quality and DED indicated that patients with DED had a higher risk of poor sleep quality compared to healthy patients. Patients with DED should be educated about the steps and techniques to improve their sleep patterns.

Alterations of Ocular Surface and Tear Film in Patients with Obstructive Sleep Apnea/Hypopnea Syndrome

PURPOSE

Obstructive sleep apnea/hypopnea syndrome (OSA) results in repeated oxygen desaturation, repeated arousals, and episodic nocturnal activation of sympathetic nervous system during sleep. Untreated OSA is strongly associated with an increase of cardio- and cerebrovascular disorders, as well as the damages of ophthalmological microstructures. However, previous literature only simply studied the association between the ophthalmic disorders and OSA. In the present study, we first investigated the alterations of ocular surface and tear film non-invasively with the innovated corneal topographer in untreated OSA patients and normal control subjects. Furthermore, we analyzed in depth whether the correlations between OSA severity and ocular surface exams exist.

PARTICIPANTS AND METHODS

Participants underwent a full-night polysomnography to determine OSA occurrence and severity. All participants subsequently received Ocular Surface Disease Index questionnaire and comprehensive ocular exams, including floppy eyelid syndrome (FES) assessment, oculus scan for tear meniscus height, non-invasive keratograph tear film breakup time (NIKBUT), and ocular surface redness, endothelial cell density, and corneal fluorescein staining.

RESULTS

One hundred eighty-one participants were prospectively enrolled in the study. FES was found in 11.5% of the normal control group and 60.0% of the severe OSA group (p=0.0005). There were significant differences in the first-NIKBUT (F-NIKBUT) (p < 0.0001), average-NIKBUT (A-NIKBUT) (p = 0.0007), and redness scores over the nasal bulbar (p = 0.032), temporal bulbar (p < 0.0001), nasal limbal (p = 0.014), and temporal limbal (p < 0.0001) areas among the four groups. F-NIKBUT and A-NIKBUT were significantly shorter in the moderate/severe OSA group (apnea/hypopnea index (AHI) ≥15) than in the normal/mild OSA group (AHI <15) (both p < 0.0001). The redness scores over the temporal bulbar (p < 0.0001) and temporal limbal (p < 0.0001) areas were also significantly different in these two OSA groups. Moreover, F-NIKBUT and A-NIKBUT negatively correlated with AHI. Nasal bulbar redness, temporal bulbar redness, nasal limbal redness, and temporal limbal redness positively correlated with AHI.

CONCLUSION

OSA patients had higher occurrence of FES. The NIKBUT was significantly shorter, and the temporal conjunctival redness scores over bulbar and limbal areas were higher in the moderate/severe OSA group than in the normal/mild OSA group. NIKBUT and conjunctival hyperemia significantly correlated with the severity of untreated OSA.

The Association Between Dry Eye and Sleep Disorders: The Evidence and Possible Mechanisms

Dry eye is a disease that severely affects patients' quality of life, increasing the global burden on public health and finance. There is growing evidence that a poor lifestyle is a significant risk factor for dry eye. Along with the development of society, sleep, as a way of life, is also constantly changing. The main manifestations of sleep disorders are reduced sleep time, circadian rhythm disturbances, and sleep breathing disturbances. Sleep disorders and their secondary systemic diseases have attracted wide attention in recent years. This review mainly explored the correlation between sleep disorders and dry eye, and found that sleep-related problems and other factors potentially leading from sleep disorders could be critical factors for dry eye. These results suggest that ophthalmologists should pay attention to the sleep health problems in patients with dry eye, and we hope that this paper can provide help for future research in this field.

Ocular Complications of Obstructive Sleep Apnea

Obstructive sleep apnea (OSA), the most common form of sleep-disordered breathing, is characterized by repetitive episodes of paused breathing during sleep, which in turn induces transient nocturnal hypoxia and hypercapnia. The high prevalence of OSA and its associated health consequences place a heavy burden on the healthcare system. In particular, the consequent episodic oxygenic desaturation/reoxygenation series and arousals from sleep in patients with OSA have the potential to trigger oxidative stress, elevated systemic inflammatory responses, and autonomic dysfunction with sympathetic activation. Given these adverse side-effects, OSA is highly correlated to many eye diseases that are common in everyday ophthalmic practices. Some of these ocular consequences are reversible, but they may permanently threaten a patient’s vision if not treated appropriately. Here, this article seeks to review the ocular consequences and potential pathophysiologic associations in patients with OSA. Understanding these OSA-related eye diseases may help clinicians provide comprehensive care to their patients.

Evaluation of Meibomian Glands in Obstructive Sleep Apnea-Hypopnea Syndrome

PURPOSE

To evaluate the effect of obstructive sleep apnea-hypopnea syndrome (OSAHS) on the meibomian glands, ocular surface, and tear parameters.

METHODS

The study included 59 individuals (32 subjects with OSAHS, 27 control subjects) who underwent polysomnography in the Chest Diseases Clinic. The right eyes of all individuals were evaluated in the Ophthalmology Clinic. The first noninvasive tear break-up time (f-NTBUT) and the average noninvasive tear break-up time were measured, and Schirmer test was applied. Meibography was taken (Sirius; CSO, Florence, Italy), and meiboscore was used for indexing meibography. Finally, a sample was taken for conjunctival impression cytology.

RESULTS

In the study and control groups, the median of f-NTBUT was 2.1 seconds [interquartile range (IQR); 1.5-5.0] and 5.7 seconds (IQR; 2.9-8.8) and the median of average noninvasive tear break-up time was 5.6 seconds (IQR; 3.6-9.5) and 7.2 seconds (IQR; 4.2-10.7), respectively (P = 0.007 and P = 0.487, respectively). The mean Schirmer value was 16.3 ± 5.9 mm (range; 5-25) and 17.3 ± 6.6 mm (range; 5-30) in the study and control groups (P = 0.604). In upper eyelid meibography, the median of loss in the meibomian glands was 20.10% (IQR; 11.60%-40.80%) in the study group and 14.70% (IQR; 10.40%-21.30%) in the control group (P = 0.043). In lower eyelid meibography, the median of loss in the meibomian glands was 19.00% (IQR; 13.60%-35.30%) in the study group and 12.40% (IQR; 9.10%-16.40%) in the control group (P = 0.002). The median of the Nelson grade in conjunctival impression cytology was 1 (IQR; 0-1) in the study group and 1 (IQR; 0-1) in the control group (P = 0.445).

CONCLUSIONS

The loss in the meibomian glands together with the shortened f-NTBUT shows that there could be a predisposition in OSAHS for evaporative dry eye originating from meibomian gland damage.

The relationship between dry eye and sleep quality

PURPOSE

Sleep is an important determinant of health and quality of life. This study aimed to clarify the association between dry eye and sleep quality using a large population-based cohort.

METHODS

71,761 participants (19-94 yrs, 59.4% female) from the Lifelines cohort in the Netherlands were assessed for dry eye using the Women's Health Study Dry Eye Questionnaire. Sleep quality was evaluated using the Pittsburgh Sleep Quality Index (PSQI). Logistic regression was used to examine the relationship between poor sleep quality (PSQI score >5) and dry eye, while correcting for age, sex, BMI, education, income, and 51 possible confounding comorbidities, including autoimmune diseases and psychiatric disorders.

RESULTS

Overall, 8.9% of participants had dry eye. Of these, 36.4% had poor sleep quality compared to 24.8% of controls (OR 1.52 (95%CI 1.44-1.60), P < 0.0001, corrected for age and sex). After correcting for all comorbidities, dry eye was still associated with poor sleep (OR 1.20 (95%CI 1.11-1.28), P < 0.0001). This relationship was seen across all ages and sexes. Patients with dry eye scored worse on all subcomponents of the PSQI. Almost one-in-two (44.9%) persons with dry eye symptoms "often" or "constantly" had poor sleep quality. This proportion was similar to participants with sleep apnea and osteoarthritis. Additionally, increasing symptom frequency was tied to increased prevalence of poor sleep quality.

CONCLUSIONS

All components of sleep quality were significantly reduced in participants with dry eye, even after correcting for comorbidities. These results indicate the substantial impact of dry eye on patients' lives, especially for those with frequent symptoms.

Function and Morphology of the Meibomian Glands Using a LipiView Interferometer in Rotating Shift Medical Staff

Purpose

To investigate the function and morphology of meibomian glands (MG) in night shift medical staff (MS).

Methods

Sixty-two eyes of 31 patients in the MS group and 59 eyes of 31 patients in the control group were consecutively enrolled. All participants completed Ocular Surface Disease Index (OSDI) and Standard Patient Dry Eye Evaluation (SPEED) questionnaires for dry eye severity, as well as Schirmer I and tear break-up time (TBUT) tests. LipiView® II Ocular Surface Interferometer was used for lipid layer thickness (LLT), MG dropout, and partial blink (PB) rate tests. MG expression was measured with an MG evaluator.

Results

The OSDI score in the MS group was 22.39 ± 13.42, which was significantly higher than that in the control group (9.87 ± 6.64 Z = −3.997, P=0.001). The SPEED score in the MS group was 7.94 ± 3.81, which was significantly higher than in the control group (3.65 ± 2.11, Z = −4.766, P=0.001). There was no significant difference in Schirmer I test between the MS group and control group (Z = −1.346, P=0.178). TBUT in MS group was significantly shorter than that in the control group (Z = −5.201, P=0.001). The mean LLT of the MS group was 55.02 ± 21.17 nm significantly thinner than that of the control group 72.76 ± 21.62 nm (Z = −4.482, P=0.001). MG loss occurred in 45.16% of affected eyes in the MS group and 16.13% of affected eyes in the control group, and the difference was statistically significant (χ² = 14.352, P=0.001). MG yielding liquid secretion and MG yielding secretion score were significantly lower in the MS group than in the control group (Z = −3.641, P=0.001; Z = −3.146, P=0.001, resp.). There was a negative correlation between mean LLT and SPEED score (Spearman r = −0.363, P=0.045).

Conclusions

Night shift MS had a higher incidence of MGD compared to day workers.

Ocular pathology associated with obstructive sleep apnea syndrome

Objective: The purpose of this study was to describe the ophthalmological findings in patients with obstructive sleep apnea syndrome (OSAS). Methods: The study group was made up of 65 patients with OSAS diagnosis and the findings were compared with the ones of the control group (n=39), which comprised patients without OSAS. An observational, analytic study, with a transversal component and a prospective component, was performed. Results: The IOP (intraocular pressure) was similar in both groups (p=0,9786). In the OSAS group, IOP increased with a higher AHI (apnea/ hypopnea index), but not significantly (p=0,057). Similarly, there was no correlation between a higher AHI and the lacrimal secretion in the OSAS group (p=0,3282). However, when we compared control with OSAS patients, we found a significantly higher degree of lacrimal hyposecretion in the latter (p=0,0003). CPAP treatment had no effect on IOP, as initial and final medium IOP were 15.06 and 14.89 respectively (p=0,8327). Regarding lacrimal secretion, it seems that CPAP treatment had an improving effect, as tear production rose from a 9.25 mm medium to 10.45 mm on the Schirmer I test (p=0,0118). Conclusions: Overall, OSAS patients showed similar IOP and glaucoma prevalence as the normal population. However, they had an abnormal tear secretion and a higher prevalence of eyelid laxity (a sign of floppy eyelid syndrome). Abbreviations: OSAS/ SASO = obstructive sleep apnea syndrome, AHI = apnea/ hypopnea index, CPAP = continuous positive airway pressure, FES = floppy eyelid syndrome, TSch/ TSCH = Schirmer test, IOP = intra-ocular pressure, PSG = polysomnography.

Dry eye and sleep quality: a large community-based study in Hangzhou

Study Objectives

To investigate the relationship between dry eye and sleep quality in a large community-based Chinese population.

Methods

A total of 3,070 participants aged 18–80 were recruited from a community-based study in Hangzhou, China during 2016–2017. Sleep quality was evaluated using the Chinese version of the Pittsburgh Sleep Quality Index (CPSQI), and dry eye was evaluated using the Ocular Surface Disease Index (OSDI) questionnaire. Multivariable linear regression and logistic regression models were used to investigate the associations, adjusting for age, smoking, drinking, season, and other potential confounders.

Results

Overall, CPSQI score and sleep dysfunction were significantly associated with mild, moderate, and severe dry eye (ORs for CPSQI score: 1.07, 1.13, 1.14, all p < 0.001; for sleep dysfunction: 1.31, 1.73, 1.66, all p < 0.05). Furthermore, worse OSDI score was presented in participants with worse CPSQI score or sleep dysfunction (CPSQI score > 7) (β: 0.13, 0.54; all p < 0.001). In addition, six of the seven components of CPSQI showed significant associations with dry eye (all p < 0.001), except for the component of sleep medication use. Moreover, we observed significant associations of dry eye in all three subscales of OSDI with CPSQI score and sleep dysfunction.

Conclusion

Our large, community-based study showed a strong association between poor sleep quality and an increased severity of dry eye, suggesting that preventing either one of the discomforts might alleviate the other.

Ocular surface assessment and morphological alterations in meibomian glands with meibography in obstructive sleep apnea Syndrome

PURPOSE

To evaluate ocular surface and Meibomian glands morphology of patients with obstructive sleep apnea syndrome (OSAS).

MATERIALS AND METHODS

Based on polysomnography, 36 eyes of 36 patients with severe OSAS (Group 1, apnea-hypopnea index (AHI) ≥30/h) and 24 eyes of 24 patients with primary snoring or mild OSAS (Group 2, AHI<15/h) were enrolled. Detailed eye examination along with ocular surface staining (fluorescein, 2%) according to Oxford scale, tear film break-up time (t-BUT), Schirmer 1 test, ocular surface disease index (OSDI) scoring, and evaluation of upper and lower eyelid Meibomian glands using infrared filter of slit-lamp biomicroscope were performed. In addition to grading Meibomian gland drop-out, the presence morphologic alterations such as Meibomian gland duct distortion, thinning and dilatation were also assessed.

RESULTS

The mean ages were 50.8 ± 8.3 (range, 35-68) and 47.9 ± 10.5 (range, 27-69) in Group 1 and Group 2, respectively (p = 0.616). Best-corrected visual acuity, Schirmer 1 test, Oxford scale and OSDI scores, and lower meiboscores did not differ significantly between groups. In Group 1, average t-BUT was lower (p = 0.003), upper and total (upper + lower) meiboscores were higher as compared to Group 2 (p < 0.05). The frequency of Meibomian gland duct distortion, thinning and dilatation were also significantly greater in Group 1 (p < 0.05).

CONCLUSION

Morphological changes, in addition to Meibomian glands dropout were significant in severe OSAS patients as demonstrated objectively with meibography. Schirmer 1 and t-BUT tests were in favor of evaporative type dry eye syndrome, which also support Meibomian gland alterations in severe OSAS patients.

Sleep Disorders are a Prevalent and Serious Comorbidity in Dry Eye

Purpose

Sleep is an essential life habit and closely associated with lifespan, diabetes, hypertension, and mental health. Sleep disorders are a prominent, but overlooked problem in patients with dry eye disease (DED), characterized by a poor sleep index, short sleep duration, long sleep latency, and poor subjective sleep. DED and sleep disorders are more prevalent in women than men. Moreover, sleep quality in DED is worse than in other eye diseases, including glaucoma, retinal diseases, cataract, and allergic and chronic conjunctivitis.

Methods

We reviewed the literature for studies investigating sleep and health, eyes and sleep, and DED and sleep, in terms of systemic and eye health, especially in women.

Results

Two studies reported that approximately half of patients with DED suffer from poor sleep. The severity of mood disorders, including anxiety and depression, is correlated strongly with sleep disorders in DED, and the symptoms and signs of DED, especially pain, also are correlated with sleep quality. Sleep disorders are documented in primary Sjögren's syndrome and an association with sleep apnea and depression is suggested. Primary Sjögren's syndrome includes arthritis and other rheumatic disease causing pain and fatigue; however, how sicca contributes to sleep disorders is not known.

Conclusions

Possible explanations for sleep disorders in DED may be depression, pain, and eye exposure at night. Reciprocal effects may be expected and consultation-liaison psychiatry is recommended for the management of sleep disorders in DED. Topical medication and lid heating also may be advantageous for sleep quality in DED.