Glaucoma and obstructive sleep apnoea syndrome

Associations between Nocturnal Hypoxemia and Retinal Nerve Fiber Layer Thinning: The Nagahama Study

Rationale: There have been meta-analyses that showed reduced retinal nerve fiber layer (RNFL) thickness, which is a surrogate marker of glaucoma, in patients with obstructive sleep apnea (OSA). However, the sample sizes in these reports were small (<300), and the mechanism of RNFL thinning in patients with OSA was not revealed.Objectives: To investigate the relationship of RNFL thickness with nocturnal hypoxemia or hypoxemic burden in a large-scale study.Methods: In this epidemiological study, 8,309 community residents were enrolled. The actigraphy-modified 3% oxygen desaturation index (acti-ODI3%) and cumulative percentage of sleep time with oxygen saturation <90% (acti-CT90) modified by objective sleep duration using actigraphy were measured. The hypoxemic burden is shown as acti-CT90. Circumpapillary RNFL thickness was determined using optical coherence tomography.Results: Multivariable logistic analysis models revealed that an increase in acti-CT90 was significantly associated with mean RNFL thinning after adjusting for several factors in participants without glaucoma diagnosed or treated previously (β = -0.037; P = 0.009). There were significant differences in mean RNFL thickness among participants stratified according to acti-CT90 (>1.5 vs. ⩽1.5; P = 0.04). Although acti-ODI3% was significantly associated with acti-CT90 (β = 0.72; P < 0.0001), acti-ODI3% was not significantly associated with mean RNFL thickness in the multivariable logistic analysis (β = -0.011; P = 0.48). In addition, acti-CT90 was significantly associated with mean RNFL thickness both in the elderly (⩾60 yr; β = -0.058; P = 0.002) and nonelderly (<60 yr; β = -0.054; P = 0.007).Conclusions: Acti-CT90, but not acti-ODI3%, was associated with mean RNFL thinning in participants irrespective of age in the elderly or nonelderly. Further prospective studies are required to investigate whether the prevention of hypoxic burden, which was shown as acti-CT90 in this study, is favorable for RNFL thinning.

[Primary open angle glaucoma and sleep apnea syndrome: A review of the literature]

The relationship between glaucoma and Obstructive Sleep Apnea Syndrome (OSAS) has long been discussed, with conflicting study findings. OSAS appears in the most recent studies to be more of an aggravating factor than an independent risk factor for glaucoma. Patients with OSAS may develop a more rapid progression of primary open-angle glaucoma (POAG). OSAS may damage the optic nerve not only by increasing the intraocular pressure (IOP) but also by altering the blood supply to the optic nerve as shown by more recent work with OCT-Angiography. Although the systemic benefits of Continuous Positive Airway Pressure (CPAP) have been demonstrated, few studies have evaluated its effect on the optic nerve. CPAP might act on glaucomatous neuropathy by improving the blood supply to the optic nerve. The study of this mechanism of action might provide new insights into the relationship between OSAS and glaucoma.

Obstructive sleep apnoea and glaucoma: a systematic review and meta-analysis

INTRODUCTION

Obstructive sleep apnoea (OSA) has been thought to be associated with glaucoma, however there are many conflicting studies on this topic. With many new studies having been published since the previous meta-analysis, we believe it is important to clarify this association. Hence, in this study we meta-analyse the recent literature regarding the association between OSA and glaucoma.

METHODS

Pubmed, Embase, Scopus and Cochrane Library were searched from inception till the 28th February 2022 for observational as well as cross-sectional studies examining the association between OSA and glaucoma. Two reviewers selected studies, extracted data, graded the quality of included non-randomized studies using the Newcastle-Ottawa scale. The overall quality of evidence was assessed using GRADE. Random-effects models were used to meta-analyse the maximally covariate- adjusted associations.

RESULTS

48 studies were included in our systematic review, with 46 suitable for meta-analysis. Total study population was 4,566,984 patients. OSA was associated with a higher risk of glaucoma (OR 3.66, 95% CI 1.70 to 7.90, I2 = 98%, p < 0.01). After adjustment for various important confounders including age, gender and patient comorbidities such as hyperlipidaemia, hypertension, cardiovascular diseases and diabetes, patients with OSA had up to 40% higher odds of glaucoma. Substantial heterogeneity was eliminated through subgroup and sensitivity analyses after consideration of glaucoma subtype, OSA severity and adjustment for confounders.

CONCLUSIONS

In this meta-analysis, OSA was associated with higher risk of glaucoma, as well as more severe ocular findings characteristic of the glaucomatous disease process. We suggest more clinical studies looking into the effects of OSA treatment on the progression of glaucoma to help clinical decision making for patients.

Primary open-angle glaucoma in patients with obstructive sleep apnoea in a Colombian population: a cross-sectional study

OBJECTIVE

Determine the prevalence, functional and structural alterations of primary open-angle glaucoma (POAG) in patients with obstructive sleep apnoea (OSA).

DESIGN

Cross-sectional.

SETTING

Tertiary hospital associated with specialised center in ophthalmologic images in Bogota, Colombia.

PARTICIPANTS

150 patients, for a sample of 300 eyes, 64 women (42.7%) and 84 men (57.3%) between 40 and 91 years old with a mean age of 66.8 (±12.1) years.

INTERVENTIONS

Visual acuity, biomicroscopy, intraocular pressure, indirect gonioscopy and direct ophthalmoscopy. Patients classified as glaucoma suspects underwent automated perimetry (AP) and optical coherence tomography of the optic nerve OUTCOME MEASURE: The primary outcomes are the determination of prevalence of glaucoma suspects and POAG in patients with OSA. Secondary outcomes are the description of functional and structural alterations in computerised exams of patients with OSA.

RESULTS

The prevalence of glaucoma suspect was 12.6%, and for POAG was 17.3%. No alterations in the appearance of the optic nerve was seen in 74.6%, focal or diffuse thinning of the neuroretinal rim (16.6%) was the most frequently finding, followed by asymmetry of the disc>0.2 mm (8.6%) (p=0.005). In the AP, 41% showed arcuate, nasal step and paracentral focal defects. The mean retinal nerve fiber layer (RNFL) was normal (>80 µM) in 74% of the mild OSA group, 93.8% of the moderate group and 17.1% of the severe group. Similarly, normal (P5-90) ganglion cell complex (GCC) in 60%, 68% and 75%, respectively. Abnormal results in the mean RNFL was seen in 25.9%, 6.3% and 23.4% of the mild, moderate and severe groups, respectively. In the GCC, 39.7%, 33.3% and 25% of the patients in the aforementioned groups.

CONCLUSION

It was possible to determine the relationship between structural changes in the optic nerve and the severity of OSA. No relationship with any of the other studied variables was identified.

Long-term effects of obstructive sleep apnea and its treatment on open-angle glaucoma: a big-data cohort study

STUDY OBJECTIVES

The relationship between open-angle glaucoma (OAG) and obstructive sleep apnea (OSA) is unclear. The long-term risk for OAG after OSA diagnosis has not been investigated. Therefore, we assessed the risk for OAG among patients with OSA over a 12-year follow-up period using nationwide, population-based data.

METHODS

The OSA group was randomly selected from among 3.5 million individuals registered with the National Health Insurance Service. The non-OSA group was obtained through propensity score matching considering several variables. The primary endpoint was glaucoma diagnosis.

RESULTS

The OSA and non-OSA groups both included 6,369 individuals. The overall hazard ratio for OAG in the OSA group was 1.42 (95% confidence interval [CI]: 1.19-1.69). In subgroup analysis, the hazard ratio for OAG was 1.94 (95% CI: 1.57-2.41) for those aged > 60 years, 1.50 (95% CI: 1.20-1.89) for those with diabetes mellitus, 1.53 (95% CI: 1.26-1.86) for those with hypertension, and 0.71 (95% CI: 0.52-0.96) for those with a history of OSA surgery.

CONCLUSIONS

Over the 12-year follow-up, the risk for OAG increased after OSA diagnosis. Further research will be necessary to determine if treating OSA can mitigate this association.

CITATION

Lee T-E, Kim JS, Yeom SW, Lee MG, Lee JH, Lee H-J. Long-term effects of obstructive sleep apnea and its treatment on open-angle glaucoma: a big-data cohort study. J Clin Sleep Med. 2023;19(2):339-346.

Decreased Peripapillary and Macular Vascular Densities in Patients with Moderate/Severe Obstructive Sleep Apnea/Hypopnea Syndrome

PURPOSE

To compare peripapillary and macular vascular densities (PVDs and MVDs) between patients with obstructive sleep apnea/hypopnea syndrome (OSA) and control subjects with symptoms of sleep-related breathing disorders only by swept-source optical coherence tomography angiography (OCTA).

PARTICIPANTS AND METHODS

In this prospective study, 192 participants underwent a full-night polysomnography to determine OSA severity and subsequently received OCTA measurements as well as AngioTool software analysis.

RESULTS

A total of 146 patients with OSA (51 mild, 43 moderate, 52 severe) and 24 control subjects (apnea/hypopnea index, AHI <5) were enrolled. PVDs and MVDs in the superficial and choroidal layers were significantly different among the four groups. When participants with simple snoring/mild OSA (AHI <15) were grouped together and compared with moderate/severe OSA (AHI ≥15), PVDs were significantly lower for the latter group in the superficial layer (p = 0.0003), deep layer (p = 0.004), and choroidal layer (p = 0.003). MVDs were also lower for the moderate/severe OSA group in the superficial (p = 0.012) and choroidal layer (p = 0.004). Negative correlations were identified between AHI and PVDs in the superficial layer (ρ = -0.257, p = 0.0007), deep layer (ρ = -0.197, p = 0.0102) and choroidal layer (ρ = -0.220, p = 0.0039) and between AHI and MVDs in the superficial layer (ρ = -0.199, p = 0.0094) and choroid layer (ρ = -0.186, p = 0.0152).

CONCLUSION

PVDs and MVDs were significantly lower in patients with moderate/severe OSA as compared to subjects with simple snoring/mild OSA. Furthermore, decreased PVDs and MVDs significantly correlated with OSA severity.

Association Between Risk of Obstructive Sleep Apnea and Glaucoma: The Singapore Epidemiology of Eye Diseases Study

PRCIS

In this population-based, cross-sectional study of Indian and Malay adults in Singapore aged 40 years or above, intermediate or high risk of obstructive sleep apnea (OSA) was associated with 50% higher odds of having glaucoma.

BACKGROUND/AIMS

The relationship between OSA and glaucoma is unclear. We assessed the association between the risk of OSA and glaucoma in an Asian population.

MATERIALS AND METHODS

In this population-based, cross-sectional study, we included Indian and Malay adults aged 40 years or above recruited between 2011 and 2015. Glaucoma was assessed by trained ophthalmologists and classified into primary open angle glaucoma (POAG) and primary angle closure glaucoma (PACG). OSA risk was assessed with the Snoring, Tiredness, Observed apnea, High blood pressure, Body mass index, Age, Neck circumference, and male Gender (STOP-Bang) questionnaire and categorized as low risk (<3) or intermediate/higher risk (≥3). We used multivariable logistic regression models to evaluate the relationship between risk of OSA and glaucoma adjusted for key variables, and further stratified for subtype and ethnicity.

RESULTS

Of the 3126 participants (mean age: 63.1±9.6 y; 52.5% female), 134 (4.3%) had glaucoma, comprising 86 (2.8%) POAG, 22 (0.7%) PACG and 26 (0.8%) secondary glaucomas, and 1182 (37.8%) had an intermediate/higher risk of OSA. Compared with individuals with a low risk of OSA, individuals with intermediate/higher risk had 50% greater odds of having glaucoma (odds ratio: 1.55, 95% confidence interval: 1.03-2.33; P =0.035). We observed a nonsignificant increase in likelihood of having POAG in those with intermediate/higher risk of OSA compared with those with low risk. The OSA-glaucoma relationship was modified by ethnicity, with Malays with intermediate/higher risk of OSA having a 2-fold risk of having any glaucoma (odds ratio: 2.01, 95% confidence interval: 1.12-3.59 P =0.019); while the same elevated risk was not observed for Indians.

CONCLUSIONS

Intermediate or high risk of OSA is associated with 50% higher odds of having glaucoma in our Singaporean population, with a 2-fold higher risk of glaucoma observed in Malays (but not Indians); however a conformational sleep study is needed.

Obstructive Sleep Apnea Affects Lacrimal Gland Function

Purpose

To determine the effect of obstructive sleep apnea syndrome (OSA) on lacrimal gland function and its mechanism.

Methods

Male mice aged seven to eight weeks were housed in cages with cyclic intermittent hypoxia to mimic OSA, and the control group was kept in a normal environment. Slit-lamp observation, fluorescein staining, and corneal sensitivity detection are used to assess cornea changes. Tear secretion was detected by phenol red cotton thread, and the pathological changes of lacrimal gland were observed by hematoxylin and eosin staining, oil red O staining, cholesterol and triglyceride kits, immunofluorescence staining, immunohistochemical staining, real-time polymerase chain reaction, transmission electron microscopy, and Western blot.

Results

Studies revealed a decreased tear secretion, corneal epithelial defects and corneal hypersensitivity. Myoepithelial cell damage, abnormal lipid accumulation, reduced cell proliferation, increased apoptosis and inflammatory cell infiltration in the lacrimal gland were also seen. Hifα and NF-κB signaling pathways, moreover, were activated, while Pparα was downregulated, in the lacrimal glands of OSA mice. Fenofibrate treatment significantly alleviated pathological changes of the lacrimal gland induced by OSA.

Conclusion

OSA disturbs the Hifα/Pparα/NF-κB signaling axis, which affects lacrimal gland structure and function and induces dry eye.

Prospective evaluation of the comorbidity of obstructive sleep apnea in patients with glaucoma

STUDY OBJECTIVES

This study aimed to identify prospectively the correlation between obstructive sleep apnea (OSA) severity, ocular microcirculation changes, and visual function changes in patients with glaucoma.

METHODS

We prospectively enrolled patients with glaucoma who were willing to undergo overnight polysomnography. The enrolled patients were further divided into normal tension glaucoma, high-tension glaucoma, and control. Visual field progression was analyzed using sequential standard automated perimetry. Peripapillary and macular vessel density were assessed through optical coherence tomography angiography (OCT-angiography). The associations between polysomnography parameters, OCT-angiography parameters, and visual field progression were analyzed.

RESULTS

A total of 22 patients with normal tension glaucoma, 30 patients with high-tension glaucoma, and 24 control patients were enrolled. Through regression analysis, glaucoma was found to be an independent predictor of moderate-to-severe OSA (P = .035); furthermore, moderate-to-severe OSA was significantly associated with visual field progression (P = .008 in the high-tension glaucoma subgroup and P = .008 in the overall glaucoma). Additionally, OSA severity was negatively correlated with the ganglion cell complex thinning rate in the normal tension glaucoma subgroup.

CONCLUSIONS

Presence of glaucoma increased the risk of moderate-to-severe OSA compared with the control group. OSA severity was related to visual field deterioration in patients with glaucoma and further associated with structural progression in the normal tension glaucoma subgroup. Careful monitoring of the comorbid OSA status of patients with glaucoma is essential to prevent disease progression.

CITATION

Chan Y-H, Chuang L-H, Yu C-C, et al. Prospective evaluation of the comorbidity of obstructive sleep apnea in patients with glaucoma. J Clin Sleep Med. 2022;18(1):47-56.

Sleep apnea and eye diseases: evidence of association and potential pathogenic mechanisms

Eye diseases are an important group of increasingly prevalent disorders that contribute very significantly to disability and represent a considerable health burden. Some data suggest that several of these diseases may be associated with sleep-disordered breathing, mainly obstructive sleep apnea (OSA), due to intermediate mechanisms, such as intermittent hypoxia or sleep fragmentation. The aims of this systematic review were to identify and critically evaluate the current evidence supporting the existence of a possible relationship between OSA and the more relevant eye diseases as well as to evaluate the potential pathogenic mechanisms. There is a body of largely low-level evidence for the association of OSA with glaucoma, nonarteritic ischemic optic neuropathy, central serous chorioretinopathy, and diabetic retinopathy. Meta-analysis of available case-control studies shows that OSA increases the risk of glaucoma (pooled odds ratio: 1.50; 95% confidence interval: 1.25 to 1.80; P < .001), nonarteritic ischemic optic neuropathy (3.62; 1.94 to 6.76; P < .001), and diabetic retinopathy (1.57; 1.09 to 2.27; P = .02). Moreover, several pathogenic pathways have been identified, mainly related to hypoxic damage, mechanical stress, systemic inflammation, oxidative stress, sympathetic tone, and endothelial dysfunction. In contrast, information about the effect of apnea-hypopnea suppression on the development and progression of eye damage is either nonexistent or of a very low level of evidence. In conclusion, OSA has emerged as an additional potential risk factor for many eye diseases, although their link is weak and contradictory, so further examination is required.

CITATION

García-Sánchez A, Villalaín I, Asencio M, García J, García-Rio F. Sleep apnea and eye diseases: evidence of association and potential pathogenic mechanisms. J Clin Sleep Med. 2022;18(1):265-278.

Clinical Practice Management of Primary Open-Angle Glaucoma in the United States: An Analysis of Real-World Evidence

PURPOSE

To investigate clinical management of primary open-angle glaucoma (POAG) in the United States using real-world evidence and to examine healthcare resource utilization (HCRU), medication adherence/persistence, and procedure use.

DESIGN

A cross-sectional, retrospective analysis of Optum's de-identified Market Clarity Dataset (July 1, 2013-December 31, 2019).

PATIENTS AND METHODS

Patients ≥18 years with POAG diagnosis and continuous enrollment for 1-year pre- and post-index were eligible and categorized into four mutually exclusive cohorts: CH1, treated with antiglaucoma medication(s) only; CH2, underwent glaucoma procedure(s) only; CH3, treated with antiglaucoma medication(s) and underwent procedure(s); and CH4, received no treatment for POAG. Adherence and persistence with antiglaucoma medications, and disease-specific HCRU were analyzed. Pairwise two-sample comparisons and multivariate regressions were conducted.

RESULTS

Examined 232,572 eligible patients (CH1=60,895; CH2=4330; CH3=6027; CH4=161,320). Prostaglandin analogs were most prescribed antiglaucoma medications (CH1: 69.7%; CH3: 62.7%), of which latanoprost was most common (CH1: 51.3%; CH3: 46.1%). Disease-specific office visits occurred in 26.3%, 78.2%, 75.0%, 23.8%, and surgical services visits occurred in 3.8%, 36.3%, 42.5%, 3.3%, in CH1-CH4, respectively. Adherence was higher (medication possession ratio: 47.1% vs 39.4%; P<0.0001), and more patients remained persistent across 1-year post-index period in CH1 vs CH3 (25.4% vs 16.1%; P<0.0001). Positive predictors of medication persistence included being female, ≥55 years, and history of dyslipidemia or thyroid disease (all P≤0.0003).

CONCLUSION

Overall, 70% POAG patients might not have received antiglaucoma treatment. Since POAG is a slowly progressive blinding disease, the lack of antiglaucoma treatment and suboptimal adherence/persistence with medications are of major concerns. Targeted screening and educational approaches are needed to improve POAG management.

Optic Nerve Head Hemoglobin Levels in Glaucoma: A Structural and Functional Correlation Study

Purpose

To investigate structural and functional correlations in glaucoma patients using optic nerve head hemoglobin (ONH Hb) measurements as determined by automated colorimetric analysis of conventional retinography.

Methods

We prospectively enrolled healthy participants and glaucomatous patients with a wide range of disease stages. All participants underwent visual field (VF) testing (standard automated perimetry, SAP), color fundus imaging (mydriatic retinography), and peripapillary retinal nerve fiber layer (pRNFL) assessment through spectral-domain optical coherence tomography (SD-OCT). Software Laguna ONhE was used to estimate the amount of ONH Hb and to determine the glaucoma discriminant function (GDF) index. Scatter plots were constructed, and regression analysis was used to investigate the correlations between GDF, average pRNFL thickness, and VF mean deviation (VFMD) index values. A secondary analysis was performed to compare each parameter between three different glaucoma groups divided according to VFMD values (mild, >−6 dB; moderate, −6 to −12 dB; and advanced, <−12 dB).

Results

One hundred ninety-six eyes from 123 participants (69 with glaucoma and 54 controls) were enrolled. Overall, all parameters evaluated differed significantly between glaucomatous and control eyes (p ≤ 0.001). The comparison of each parameter according to groups of disease stages revealed significant differences between controls and each of the glaucomatous groups (p < 0.001). More pronounced changes in GDF values were observed in early disease stages. We found significant nonlinear correlations between GDF and VFMD values (R² = 0.295, p < 0.001) and between pRNFL thickness and VFMD (R² = 0.598, p < 0.001). A linear correlation was found between GDF and pRNFL thickness values (R² = 0.195, p < 0.001).

Conclusion

Our results showed significant associations between ONH Hb values and both structural and functional damage in glaucoma obtained by SD-OCT and SAP, respectively. The nonlinear correlation we found and the GDF behavior along different disease stages suggest that ONH Hb levels' reduction may precede visual function changes in early glaucoma stages.

Nonocular Influencing Factors for Primary Glaucoma: An Umbrella Review of Meta-Analysis

INTRODUCTION

Glaucoma is the main cause of irreversible blindness worldwide. Still, little is known about nonocular risk factors. We use an umbrella review to examine the meta-analytic evidence of the correlation between nonocular factors and glaucoma.

METHOD

We searched PubMed and Embase databases up to July 24, 2020. Eligible meta-analyses (MAs) included cohort, case-control, and randomized controlled study designs. Two authors independently extracted the data and evaluated the methodological quality of the MAs. AMSTAR 2 was used to assess the methodological quality of each included MA.

RESULTS

This umbrella review contains 22 MAs with 22 unique nonocular factors in total. We identified 11 factors that increase the risk of glaucoma: hyperlipidemia, nocturnal dip in blood pressure, infection with Helicobacter pylori, myopia, obstructive sleep apnea syndrome, corneal properties, diabetes, hypertension, hypothyroidism, migraine, and plasma homocysteine. We identified 3 factors that reduce the risk of glaucoma: dietary intake of vitamin A, dietary intake of vitamin C, and short-term statin use. We identified 8 factors that had no association with glaucoma: dietary intake of vitamin B, dietary intake of vitamin E, cigarette smoking, Alzheimer's disease, serum folic acid, serum vitamin B6, serum vitamin B12, and serum vitamin D.

CONCLUSIONS

In this umbrella review of MAs, evidence was found for associations of various nonocular factors with glaucoma to different degrees. However, risk factors were only mildly associated, suggesting low impact of systemic risk factors. Additional higher quality studies are needed to provide robust evidence.

Pathophysiology of the comorbidity of glaucoma with obstructive sleep apnea: A postulation

Glaucoma is a serious and progressive optic neuropathy, the exact pathophysiology of which is still poorly understood. Furthermore, glaucoma exhibits significant comorbidity with obstructive sleep apnea (OSA) that warrants an in-depth study in view of highly probable beneficial and far-reaching clinical implications. In this brief paper, the authors have studied the existing theories in an attempt to explain the comorbidity and its underlying pathophysiology. From the ensuing evidence, the role of connective tissue strength has emerged as a major factor and which appears to play a pivotal role not only in the development of glaucoma but also in the underlying pathophysiology of its enigmatic comorbidity with OSA. Understanding the pathophysiology of the comorbidity can stimulate newer therapeutic strategies targeted toward strengthening of connective tissues that may at least retard if not arrest the progression of glaucomatous changes and their complications.

Evaluation of Retinal Nerve Fiber Layer Thickness and Optic Nerve Head Parameters in Obstructive Sleep Apnoea Patients

PURPOSE

To study the retinal nerve fiber layer (RNFL) thickness and optic nerve head (ONH) parameters in obstructive sleep apnoea (OSA) patients and their relationship with severity of the disease.

METHODS

A cross-sectional, hospital-based study. Fifty-four OSA subjects and 54 controls were recruited. Candidate that fulfil the criteria with normal ocular examinations then proceed with spectrum domain Cirrus optical coherence tomography examinations. ONH parameters and RNFL thickness were evaluated. Apnoea-hypopnoea index (AHI) of the OSA group were obtained from the medical record.

RESULTS

In OSA, mean of average RNFL thickness was 93.87 µm, standard deviation (SD) = 9.17, p = 0.008 (p < 0.05) while superior RNFL thickness was 113.59 µm, SD = 16.29, p ≤ 0.001 (p < 0.05). RNFL thickness fairly correlate with severity of the disease (AHI), superior RNFL with R = 0.293, R2 = 0.087, p = 0.030 (p < 0.05), and nasal RNFL R = 0.292, R2 = 0.085, p = 0.032. No significant difference and correlation observed on ONH parameters. In control group, mean of average RNFL thickness was 98.96 µm, SD = 10.50, p = 0.008 (p < 0.05) while superior RNFL thickness was 125.76 µm, SD = 14.93, p ≤ 0.001 (p < 0.05).

CONCLUSIONS

The mean of the average and superior RNFL thickness were significantly lower in the OSA group compare to control. Regression analysis showed RNFL thickness having significantly linear relationship with the AHI, specifically involving the superior and nasal quadrant.

Ganglion cell layer thickening in patients suffering from Obstructive Sleep Apnea-Hypopnea syndrome with long Mean Apnea-Hypopnea Duration during sleep

PURPOSE

To study the effects of mean apnea-hypopnea duration (MAD), a useful indicator of blood oxygenation, on peripapillary retinal nerve fiber layer (RNFL), macular ganglion cell to inner plexiform layer (GC-IPL) and macular retinal thickness in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).

METHODS

Sixty-five patients recently diagnosed with OSAHS and 35 healthy individuals were enrolled in this cross-sectional study. OSAHS patients were divided according to their MAD values into group 1 with 16 participants (MAD:10-15.5 s), group 2 with 17 participants (MAD:15.5-19 s), group 3 with 17 participants (MAD:19-30 s) and group 4 with 15 participants (MAD > 30 s). The average and sectorial values of RNFL, GC-IPL and retinal thickness were measured by SS-OCT (DRI OCT Triton, Topcon). Intraocular pressure was recorded by Goldmann Applanation and Pascal Dynamic Contour Tonometer (DCT-IOP).

RESULTS

The average RNFL and retinal thickness values were higher in group 4, but did not reach statistical significance. With the exception of the central 1 mm at the fovea, GC-IPL was always thickened in group 4, and significant differences were evident when its average value was compared with group 2 (p = 0.03), its superior and inferior-nasal values were compared with group 2 (p = 0.02, p = 0.006, respectively) and group 3 (p = 0.01, p = 0.02, respectively), its superior-temporal value was compared with group 3 (p = 0.003) and the control group (p = 0.03), and its superior-nasal value was compared with group 2 (p = 0.03), group 3 (p = 0.001) and the control group (p = 0.03). DCT-IOP was significantly positively correlated with the duration of sleep in which oxygen saturation (SaO₂ ) was decreased under 90% (r = 0.359, p = 0.01).

CONCLUSION

We report a novel observation of GC-IPL thickening in OSAHS patients experiencing long MAD, a parameter which incorporates the severity of breathing events during sleep. Higher DCT-IOP was noted with advancing hypoxemia.

Links between obstructive sleep apnea and glaucoma neurodegeneration

In the last few years, the possible link between obstructive sleep apnea (OSAS) and glaucoma, has attracted the interest of many scientists, especially in those forms of primary open angle glaucoma (POAG) and normal tension glaucoma (NTG), in which a progression of the disease occurs, even though intraocular pressure (IOP) is in the range of normality. The increased prevalence of POAG or NTG in patients affected by OSAS, and vice versa, has stimulated interest in the pathogenetic mechanisms that could trigger these two diseases. Hypoxia generated by apnea/hypopnea cycles has been identified as the main cause of many changes in the vascular and neurological systems, which alter the functioning not only of the optic nerve, but also of the whole organism. However, many other factors could be involved, like mechanical factors, obesity, hormonal imbalance and other sleep disorders. Furthermore, the demonstration of typical glaucomatous or glaucoma-like changes in the anatomy or function of the optic nerve and retinal nerve fiber layer by sensitive specific and diagnostic methods, such as perimetry, optical coherence tomography (OCT), optical coherence tomography angiography (OCTA) and electrophysiological exams keeps interest high for this field of study. For this reason, further investigations, hopefully a source of stronger scientific evidences, are needed.

Obstructive Sleep Apnea in Patients With Primary-open Angle Glaucoma: No Role for a Screening Program

PRéCIS:: In this study, we found a high prevalence of obstructive sleep apnea (OSA) among patients with primary open-angle glaucoma (POAG) but this was not different (nor was OSA more severe) to matched people without glaucoma.

RATIONALE

It has been proposed that OSA might be a contributing factor in the development of POAG and by extension that there could be a role for screening people with POAG for OSA.

OBJECTIVES

To assess whether the prevalence of OSA among patients with POAG is different from that in people without glaucoma and to examine for associations between apnea-hypopnea index (AHI) and markers of functional and structural changes in POAG.

METHODS

Unselected POAG patients and control subjects were consecutively recruited in a single center. A comprehensive ocular assessment and nocturnal multichannel cardiorespiratory monitoring were performed.

RESULTS

Data from 395 participants, 235 POAG patients, and 160 controls were analyzed. The prevalence of OSA was 58% [95% confidence interval (CI), 52-65] in POAG patients and 54% (95% CI, 47-62) in controls, with 22% (95% CI, 16-27) of POAG patients and 16% (95% CI, 11-22) of controls diagnosed with moderate or severe OSA. A total of 160 POAG participants were matched to the controls using propensity score matching. There was no significant difference in OSA prevalence between the matched groups (P=0.91 for AHI≥5 and P=0.66 for AHI≥15). The AHI was not associated with the severity of visual field defect or retinal nerve fiber layer thinning after adjustment for confounders.

CONCLUSIONS

This study confirms a high prevalence of OSA among patients with POAG which is, however, not higher than in people without glaucoma matched for known OSA risk factors. Our results do not support screening for OSA in patients with POAG.

Prevalence of Glaucoma in Patients with Obstructive Sleep Apnea

To determine the prevalence of glaucoma in obstructive sleep apnea (OSA) patients and compare it with that of patients without OSA. Patients investigated for OSA using polysomnography at the sleep center of King Abdulaziz University Hospital were invited to participate in this cross-sectional case series study. American Academy of Sleep Medicine guidelines were used to diagnose OSA. Recruitment of patients with and without OSA was conducted from December 2013 to September 2015. Exclusion criteria included topical and systemic steroid use and presence of other ocular diseases. Two criteria, cup/disc ratio and visual field defects, were necessary for a glaucoma diagnosis. Among 84 adults enrolled, 44 (52%) had a confirmed diagnosis of OSA. Glaucoma prevalence was higher among individuals with OSA (16%) than among non-OSA individuals (8%), a difference that was not statistically significant. A consistent trend, which was not statistically significant after adjusting for cofounders, toward more glaucomatous changes was observed in OSA subjects. Although a trend toward higher glaucoma prevalence was observed in OSA patients, the difference was not statistically significant. As many variables contribute to the development of the two conditions, larger cohorts are needed to evaluate associations between glaucoma and OSA.

Ginkgo Biloba Extract in Ophthalmic and Systemic Disease, With a Focus on Normal-Tension Glaucoma

Glaucoma is a neurodegenerative eye disease that results in retinal ganglion cell loss and ultimately loss of vision. Elevated intraocular pressure (IOP) is the most common known risk factor for retinal ganglion cell damage and visual field loss, and the only modifiable risk factor proven to reduce the development and progression of glaucoma. This has greatly influenced our approach and assessment in terms of diagnosis and treatment. However, as many as ≥50% of patients with progressive vision loss from primary open angle glaucoma without IOP elevation (≤22 mm Hg) have been reported in the United States and Canada; 90% in Japan and 80% in Korea. Extensive research is currently underway to identify the etiology of risk factors for glaucoma other than or in addition to elevated IOP (so-called "normal-tension" glaucoma; NTG) and use this knowledge to expand available treatment options. Currently, Food and Drug Administration-approved medications for glaucoma exclusively target elevated IOP, suggesting the need for additional approaches to treatment options beyond the current scope as the definition of glaucoma changes to encompass cellular and molecular mechanisms. This review focuses on alternative medical approaches, specifically Ginkgo Biloba extract, as a potential treatment option for normal-tension glaucoma.

Continuous intraocular pressure monitoring in patients with obstructive sleep apnea syndrome using a contact lens sensor

Purpose

To analyse nocturnal intraocular pressure (IOP) fluctuations in patients with obstructive sleep apnea syndrome (OSAS) using a contact lens sensor (CLS) and to identify associations between the OSAS parameters determined by polysomnographic study (PSG) and IOP changes.

Method

Prospective, observational study. Twenty participants suspected of having OSAS were recruited. During PSG study, IOP was monitored using a CLS placed in the eye of the patient. The patients were classified according to the apnea-hypopnea index (AHI) in two categories, severe (>30) or mild/moderate (<30) OSAS. We evaluated several parameters determined by the IOP curves, including nocturnal elevations (acrophase) and plateau times in acrophase (PTs) defined by mathematical and visual methods.

Results

The IOP curves exhibited a nocturnal acrophase followed by PTs of varying extents at which the IOP remained higher than daytime measurement with small variations. We found significant differences in the length of the PTs in patients with severe OSAS compared to those with mild/moderate disease (P = 0.032/P = 0.028). We found a positive correlation between PTs and OSAS severity measured by the total number of apneic events (r = 0.681/0.751 P = 0.004/0.001) and AHI (r = 0.674/0.710, P = 0.004/0.002). Respiratory-related arousal and oxygen saturation also were associated significantly with the IOP PT length.

Conclusions

Periods of nocturnal IOP elevation lasted longer in severe OSAS patients than those with mild/moderate OSAS and correlate with the severity of the disease. The length of the nocturnal PT is also associated to respiratory parameters altered in patients with OSAS.

Prevalence and Predictors of Ocular Complications in Obstructive Sleep Apnea Patients: A Cross-sectional Case-control Study

Purpose:

This study sought to identify the magnitude and the possible risk factors of ocular complications in patients with Obstructive Sleep Apnea (OSA).

Methods:

A hospital-based cross-sectional study with a nested case-control design was conducted. Qualifying study subjects were patients who had been diagnosed with moderate to severe OSA (AHI index of ≥ 5, n=80), and control subjects (n=20) who had an AHI index of ≤ 5 (“normal”). Study participants were recruited from Mansoura University Hospital’s Sleep Disorders Clinic in Mansoura, Egypt.Selected subjects were assessed for ocular complications at Mansoura Univerity Hospital Ophthalmic Center, (Mansoura), Egypt. An ophthalmic history was recorded, and opthalmic testing was carried out. The testing included unaided visual acuity measurement, refraction, best-corrected visual acuity measurement, slit lamp bio-microscopic evaluation of the anterior segment and anterior segment photography, dilated fundus examination, intraocular pressure measurement, fundus photo, and fluorescein angiography, and visual field assessment. Various tests of OSA symptoms were also monitored, including the AHI, lowest oxygen concentrations and desaturation index plus the overall severity index. .

Results:

It was found that OSA patients n=28 (35%), n=24 (30%), n=4 (5%) had senile cataract, normal tension glaucoma, and retinal ischemia, respectively, with an overall prevalence of 45%. Additionally, the OSA group had seven times greater risk (OR=7.36, 95%CI: 1.6-33.86) of vision-threatening disorders compared to the controls. OSA patients were observed to be at a greater risk of senile cataract 28 (35%), normal tension glaucoma 24 (30%), retinal ischemia 4 (5%) and conjunctival hyperemia and dry eye (OR=3.77, 95%CI: 1.02-13.95, OR=4.36, 95%CI: 1.26-17.08). Also, multivariate logistic regression analysis testing showed that the lowest oxygen saturation index was the only significant predictor negatively associated with vision-threatening disorders (OR=0.84, 95%CI: 0.75-0.93).

Conclusion:

The risk of vision-threatening and non-threatening ocular disorders is higher among OSA cases. The lowest oxygen saturation index was the only significant predictor of vision-threatening disorders. These findings support the recommendation that a full ophthalmic examination should be carried out on patients with confirmed OSA.

Effects of OSA Surgery on Ophthalmological Microstructures

OBJECTIVE

Obstructive sleep apnea/hypopnea syndrome (OSA) could compromise oxygenation of the optic nerve and cause glaucomatous optic neuropathy; however, there were no studies to investigate the changes of visual function and retinal microstructures in OSA patients after upper airway surgery. We aim to assess the changes in the visual sensitivity and retinal fiber layer thickness in OSA patients before and after surgery.

METHODS

This prospective single-blind study enrolled patients with OSA from a tertiary academic medical center who had unsuccessful conservative therapy and then underwent surgery. The patients were referred for comprehensive ophthalmologic evaluation at baseline and 6 months after OSA surgery. The polysomnographic findings were collected pre- and postoperatively. Visual sensitivities on standard automated perimetry (SAP) were assessed. Peripapillary retinal nerve fiber layer (RNFL) thickness and macular layer (ML) thickness parameters were measured by spectral-domain optical coherence tomography (OCT).

RESULTS

A total of 108 OSA patients were enrolled. Six months after surgery, the major parameters of polysomnography (PSG), mean deviation, and pattern standard deviation of SAP significantly improved in these OSA patients. Regarding the OCT parameters, thickness of ML in the nasal-outer, superior-inner, temporal-inner, inferior-inner, nasal-inner sectors, and total ML thickness significantly increased 6 months after upper airway surgery in the severe OSA group (apnea/hypopnea index ⩾30 per hour).

CONCLUSION

The visual sensitivities on SAP, ML thickness on OCT, and oxygenation status on PSG significantly improved 6 months after upper airway surgery in patients with severe OSA. Upper airway surgery may ameliorate the microstructures of the retina in patients with severe OSA.

Visual field defects and retinal nerve fiber imaging in patients with obstructive sleep apnea syndrome and in healthy controls

Background

To assess the retinal sensitivity in obstructive sleep apnea hypopnea syndrome (OSAHS) patients evaluated with standard automated perimetry (SAP). And to correlate the functional SAP results with structural parameters obtained with optical coherence tomography (OCT).

Methods

This prospective, observational, case-control study consisted of 63 eyes of 63 OSAHS patients (mean age 51.7 ± 12.7 years, best corrected visual acuity ≥20/25, refractive error less than three spherical or two cylindrical diopters, and intraocular pressure < 21 mmHg) who were enrolled and compared with 38 eyes of 38 age-matched controls. Peripapillary retinal nerve fiber layer (RNFL) thickness was measured by Stratus OCT and SAP sensitivities and indices were explored with Humphrey Field Analyzer perimeter. Correlations between functional and structural parameters were calculated, as well as the relationship between ophthalmologic and systemic indices in OSAHS patients.

Results

OSAHS patients showed a significant reduction of the sensitivity for superior visual field division (p = 0.034, t-student test). When dividing the OSAHS group in accordance with the severity of the disease, nasal peripapillary RNFL thickness was significantly lower in severe OSAHS than that in controls and mild-moderate cases (p = 0.031 and p = 0.016 respectively, Mann-Whitney U test). There were no differences between groups for SAP parameters.

We found no correlation between structural and functional variables. The central visual field sensitivity of the SAP revealed a poor Pearson correlation with the apnea-hipopnea index (0.284, p = 0.024).

Conclusions

Retinal sensitivity show minor differences between healthy subjects and OSAHS. Functional deterioration in OSAHS patients is not easy to demonstrate with visual field examination.

Effect of prolonged supine position on the intraocular pressure in patients with obstructive sleep apnea syndrome

PURPOSE

Obstructive sleep apnea syndrome (OSAS) patients are at risk of glaucoma but the risk increases if they have higher intraocular pressure (IOP) while sleeping. We aim to evaluate the postural effect of upright and prolong supine positions on IOP in these patients.

METHODS

This is a cross-sectional study involving 27 patients with symptoms of OSAS seen at a tertiary institutional center and 25 normal controls performed between June 2015 and June 2016. All patients and controls underwent a polysomnography (PSG) test and were diagnosed with OSAS based on the apnea-hypopnea index (AHI). Patients are those with OSAS symptoms and had AHI > 5, whereas controls are staffs from the ophthalmology clinic without clinical criteria for OSAS and had PSG result of AHI < 5. IOP was measured 10 min after sitting, immediately and at 30 min on supine position and immediately after resuming sitting position. The main outcome measures were the changes in mean IOP in different positions.

RESULTS

The increase in mean IOP when changing from sitting to supine position was significantly higher in OSAS patients in both the right eye (RE) (1.01 ± 1.14 vs 0.44 ± 0.41 mmHg, p = 0.033) and left eye (LE) (1.20 ± 1.26 vs 0.48 ± 0.62 mmHg, p = 0.044). After 30 min supine, the IOP in OSAS patients showed a further increase in IOP than controls (RE 1.20 ± 1.79 vs 0.12 ± 0.66 mmHg, p = 0.001 and LE 0.59 ± 2.00 vs 0.15 ± 0.78 mmHg, p = 0.246). Higher IOP when sitting post supine is associated with higher IOP on supine position.

CONCLUSION

IOP increase is significantly more in OSAS patients on prolong supine position.

Lifestyles guide and glaucoma (II). Diet, supplements, drugs, sleep, pregnancy, and systemic hypertension

PURPOSE

To establish evidence based guidelines to advise patients on the relationship between habits, diet, certain circumstances, diseases and glaucoma.

METHODS

Review of all published articles on glaucoma and sports or other activities. The papers were classified according to the level of scientific evidence based on the Oxford Centre for Evidence-based Medicine classification.

RESULTS

The evidence on the relationship between diet or supplements and the incidence or progression of glaucoma is insufficient to make a general recommendation for glaucoma patients. Although some studies on normal tension glaucoma suggest that Gingko biloba could reduce glaucoma progression, the results do not allow a general recommendation for all these patients. Similarly, the evidence on the usefulness of vitamin supplements is not conclusive. The studies on smoking do not clearly demonstrate the relationship between this habit and incidence of glaucoma. Marihuana is not a useful treatment for glaucoma. Although the results on the relationship between sleep apnoea and glaucoma are heterogeneous, it is recommended that patients with moderate to intense apnoea are tested for glaucoma. Pregnancy does not influence the course of the disease, but several hypotensive drugs may be harmful for the foetus. Nocturnal systemic hypotension is a risk factor for glaucoma progression.

CONCLUSIONS

Certain habits, circumstances, or diseases may have an influence on the onset or progression of glaucoma. It is important to have adequate information about the scientific evidence in the publications in order to properly advise patients.

Prevalence of primary open-angle glaucoma among patients with obstructive sleep apnea

OBJECTIVE

Our objective was to determine primary open-angle glaucoma (POAG) prevalence among obstructive sleep apnea (OSA) patients because the perioperative environment risks further damaging the optic nerve.

STUDY DESIGN

We analyzed a "convenience sample" referred by Sleep Medicine for oral appliances because of continuous positive airway pressure intolerance. We determined the aggregate prevalence of the 3 POAG subtypes-"classic" open-angle glaucoma (COAG), normal-tension glaucoma (NTG), and open-angle glaucoma suspect (OAGS)-among the index population and compared it with that of same hospital's general population. Similarly determined were associations between OSA severity levels (apnea-hypopnea index [AHI]) and POAG subtypes.

RESULTS

Among the study sample of 225 patients with OSA (96.4% male; mean age 58.5 ± 12.3 years), 47 (20.9%) had POAG, with a subtype distribution of COAG: 12 (25.5%), NTG: 8 (17.0%), and OAGS: 27 (57.4%). The POAG prevalence rate among medical center's general population was 2.5%, which was significantly less (P < .00001) than among those with comorbid OSA. Severity of the breathing disorder (AHI) failed to identify a significant correlation to any POAG subtype (P > .05).

CONCLUSION

The significant prevalence of POAG among OSA sufferers suggests need for preoperative consultations from an ophthalmologist to determine eye health and possibly an anesthesiologist to avoid potential vision loss.

Ocular and Clinical Characteristics Associated with the Extent of Posterior Lamina Cribrosa Curve in Normal Tension Glaucoma

Although normal-tension glaucoma (NTG) is pathogenetically heterogenous, there have been few attempts to subclassify NTG patients according to the mechanism and anatomy of optic nerve damage. This cross-sectional study was performed to investigate differences in the clinical and ocular characteristics between NTG patient groups stratified according to the degree of posterior lamina cribrosa (LC) curve which was assessed by calculating LC curvature index (LCCI). A total of 101 eyes of 101 treatment naïve NTG patients were included. The optic nerve head was imaged using enhanced-depth-imaging spectral-domain optical coherence tomography in three horizontal B-scan images in each eye. The patients were divided into two groups based on the magnitude of LCCI using a cutoff of known upper 95 percentile value in healthy subjects: a steeply curved LC group (Group 1, 75 eyes, 74.3%) and a relatively flat LC group (Group 2, 26 eyes, 25.7%). NTG eyes with relatively flat LC had lower intraocular pressure, and were associated with greater parapapillary structural alternation and systemic risk factors. These data suggest that assessment of LC morphology may help clinicians seek additional risk factors and make inferences about the mechanism of optic nerve damage in individual patients.

The Study of Neurocognitive Outcomes, Radiological and Retinal Effects of Aspirin in Sleep Apnoea- rationale and methodology of the SNORE-ASA study

PURPOSE

Sleep disordered breathing (SDB) is highly prevalent in older adults. Increasing evidence links SDB to the risk of dementia, mediated via a number of pathways, some of which may be attenuated by low-dose aspirin. This study will evaluate, in a healthy older cohort, the prospective relationship between SDB and cognitive function, changes in retinal and cerebral microvasculature, and determine whether low-dose aspirin ameliorates the effects of SDB on these outcomes over 3years.

DESIGN

SNORE-ASA is a sub-study of the ASPirin in Reducing Events in the Elderly (ASPREE) randomised, multi-centre, placebo-controlled trial evaluating the effect of daily 100mg aspirin on disability-free and dementia-free survival in the healthy older adult aged 70 and over. At baseline, 1400 ASPREE participants successfully underwent a home sleep study with a home sleep study screening device for SDB; and 296 underwent both 1.5 Tesla brain magnetic resonance imaging (MRI) and retinal vascular imaging (RVI). Cognitive testing, brain MRI and RVI is being repeated after 3years.

PRIMARY OUTCOME MEASURES

Change in the modified mini-mental state examination score. Secondary outcome measures are changes in other cognitive tests, and changes in abnormal parameters on RVI and volume of white matter hyper-intensities on brain MRI.

CONCLUSION

Identifying preventive therapies for delaying the onset of dementia is of paramount importance. The results of this study will help clarify the impact of the SDB on risk of cognitive decline and cerebral small vessel disease, and whether low-dose aspirin can ameliorate cognitive decline in the setting of SDB.

SNORE-ASA TRIAL REGISTRATION

ACTRN12612000891820: The Principal ASPREE study is registered with the International Standardized Randomized Controlled Trials Register, ASPirin in Reducing Events in the Elderly, Number: ISRCTN83772183 and clinicaltrials.gov Number NCT01038583.

Prevalence and risk factors of eye diseases in adult patients with obstructive sleep apnoea: results from the SLE.E.P.Y cohort study

OBJECTIVES

To assess the occurrence of glaucoma, eyelid, corneal and macular disorders in a cohort of patients with obstructive sleep apnoea (OSA) diagnosed by overnight polysomnography and to investigate into the risk factors for the above eye diseases (EDs).

DESIGN

Cross-sectional cohort study between 2014 and 2015.

SETTING

Unit of Respiratory Medicine and Eye Clinic of the University of Verona.

PARTICIPANTS

431 consecutive patients were considered eligible. Of these, 87 declined to participate, 35 were untraceable and 13 were deceased.

INTERVENTIONS

A complete ophthalmic evaluation of both eyes for each patient.

PRIMARY AND SECONDARY OUTCOME MEASURES

Best-corrected distance visual acuity, intraocular pressure, corneal, macular and optic nerve optical coherence tomography, ocular aberrometry, optic nerve laser polarimetry, visual field test, and eyelid examination.

RESULTS

296 patients aged 64.5±12.8 years, 23% female and 77% male, underwent ophthalmic examination. There was 56% (n=166) prevalence of eyelid disorders, 27% (n=80) of corneal disorders, 13% (n=39) of macular disorders and 11% (n=33) of glaucoma. Advancing age was not associated with the severity of OSA, while significant differences were found for gender, body mass index, Oxygen Desaturation Index, smoking habit, hypertension and diabetes. Severe OSA was significantly associated with glaucoma (OR, 95% CI 1.05 to 5.93, p=0.037).

CONCLUSIONS

EDs were more prevalent in our patinets with OSA than in the general population. Severe Apnoea/Hypopnoea Index level seemed to play a role as risk factor only for glaucoma.

Repercusiones oftalmológicas del síndrome de apnea-hipopnea obstructiva del sueño (SAHOS)

Las manifestaciones oftalmológicas que se relacionan con el síndrome de apnea-hipopnea obstructiva del sueño (SAHOS) incluyen síndrome de párpado flácido y cambios a nivel del nervio óptico asociados con glaucoma, así como neuropatía óptica isquémica anterior no arterítica y papiledema. La prevalencia del síndrome de párpado flácido en pacientes con SAHOS varía entre 2.3% y 32.6%, mientras que de la asociación entre glaucoma y SAHOS oscila entre 2% y 27%.En la población estudiada en Colombia se encuentra una frecuencia de 2.7% de asociación entre glaucoma de presión normal y SAHOS. El glaucoma presente en estos casos es el primario de ángulo abierto, que bien puede cursar con o sin un aumento de la presión intraocular. En cuanto a la neuropatía óptica isquémica y el papiledema, no se dispone de datos acerca de su prevalencia en pacientes con SAHOS. Se recomienda la valoración por oftalmología a los pacientes diagnosticados con este síndrome.

Increased stroke risk among patients with open-angle glaucoma: a 10-year follow-up cohort study

BACKGROUND

Although several studies showed the association between stroke and open-angle glaucoma (OAG), there is still lack of longitudinal studies based on large populations. Therefore, in this study, we investigated the risk of stroke after OAG diagnosis over a 10-year follow-up period.

METHODS

We performed a retrospective nationwide propensity score-matched cohort study. OAG and comparison groups were selected from a large database from the Korean National Health Insurance Service, comprising 1 025 340 random subjects. The OAG group comprised patients with an initial diagnosis of OAG between January 2004 and December 2007 (n=1520), and the comparison group comprised randomly selected patients (five per glaucoma patient; n=7570). Each cohort was tracked until 2013 for stroke development. Cox proportional hazard regression analysis was performed to determine possible association RESULTS: OAG was associated with increased stroke incidence (HR=1.20, 95% CI 1.03 to 1.40). Hypertension, diabetes mellitus, chronic renal failure, atrial fibrillation, hyperlipidaemia, increasing age and male gender also increased the incidences of stroke. Risk of stroke for patients with OAG was greater in the older age group (≥65 years, HR=1.23, 95% CI 1.02 to 1.47) than in the younger age group (<65 years, HR=1.12, 95% CI 0.86 to 1.46), and greater in males (HR=1.31, 95% CI 1.06 to 1.60) than in females (HR=1.10, 95% CI 0.88 to 1.38).

CONCLUSIONS

Patients who were diagnosed with OAG were more likely to experience subsequent stroke than comparison group without OAG, and the risk was greater for older adults and males.

Intraocular pressure is sensitive to cumulative and instantaneous mental workload

We used a repeated-measures design to assess the impact of mental-task complexity on intraocular pressure (IOP). Fourteen participants performed three continuous 11-min blocks of a mental-workload task (3-back) and an oddball version of this task. Also, heart-rate variability (HRV), cognitive-performance scores, and subjective measure of mental load (NASA-TLX) were determined. IOP was taken before each block and afterwards as well as after recovery from mental tasks. We found that IOP increased during heavy mental workloads (p < 0.01). Consistent with this finding, the autonomic control (HRV) and the cognitive performance were significantly lower (p < 0.045, and p < 0.01, respectively), and the NASA-TLX scores were higher during the 3-back task (p < 0.01). We conclude that IOP is sensitive to mental workload, and it could provide a novel neuroergonomic tool to assess mental workload. Our study highlights a potential association between IOP and the nervous system's state of activation.

Twenty-four hour intraocular pressure monitoring with the SENSIMED Triggerfish contact lens: effect of body posture during sleep

PURPOSE

To determine the difference in relative intraocular pressure (IOP) measured by the SENSIMED Triggerfish (TF) contact lens in flat compared with 30° head-up sleeping positions in patients with progressive primary open-angle glaucoma or normotensive glaucoma, based on recent or recurrent disc haemorrhage.

DESIGN

Prospective, randomised, cross-over, open-label comparative study.

METHODS

IOP was monitored for 24 hours using TF on two separate sessions. Patients were randomly assigned to sleep flat one night and 30° head-up the other. Outputs in arbitrary units were obtained. Sleep and wake periods were defined as 22:00-6:00 and 8:00-22:00, respectively. Mean TF values during sleep and wake periods and wake-sleep and sleep-wake slopes were calculated for each session. TF output signals were compared between positions.

RESULTS

Twelve subjects completed the study. Significant mean positive slopes were noted during the sleep period for both positions (p<0.01). No significant differences in the TF mean values were observed between positions (p=0.51). Six (54%) subjects had mean TF values significantly higher during the flat supine session, while four (36%) subjects had higher values during the head-up session. A significant increase in Goldmann IOP (p=0.001) and TF (p=0.02) measurements were observed after 24 hours of TF wear ('drift phenomenon').

CONCLUSIONS

Sleep position affects IOP as measured by TF in some patients with progressive glaucoma. The upward drift in TF output detected in >50% of the subjects requires further investigation to establish whether the increased output values over time are an artefact induced by the TF or a real change in IOP.

TRIAL REGISTRATION NUMBER

NCT01351779.

The interaction between intracranial pressure, intraocular pressure and lamina cribrosal compression in glaucoma

This review examines some of the biomechanical consequences associated with the opposing intraocular and intracranial forces. These forces compress the lamina cribrosa and are a potential source of glaucomatous pathology. A difference between them creates a displacement force on the lamina cribrosa. Increasing intraocular pressure and/or decreasing intracranial pressure will increase the trans-lamina cribrosa pressure difference and the risk of its posterior displacement, canal expansion and the formation of pathological cupping. Both intraocular pressure and intracranial pressure can be elevated during a Valsalva manoeuvre with associated increases in both anterior and posterior lamina cribrosa loading as well as its compression. Any resulting thinning of or damage to the lamina cribrosa and/or retinal ganglion cell axons and/or astrocyte and glial cells attached to the matrix of the lamina cribrosa and/or reduction in blood flow to the lamina cribrosa may contribute to glaucomatous neuropathy. Thinning of the lamina cribrosa reduces its stiffness and increases the risk of its posterior displacement. Optic nerve head posterior displacement warrants medical or surgical lowering of intraocular pressure; however, compared to intraocular pressure, the trans-lamina cribrosa pressure difference may be more important in pressure-related pathology of the optic nerve head region. Similarly important could be increased compression loading of the lamina cribrosa. Reducing participation in activities which elevate intraocular and intracranial pressure will decrease lamina cribrosa compression exposure and may contribute to glaucoma management and may have prognostic significance for glaucoma suspects.

Glaucoma and its association with obstructive sleep apnea: A narrative review

Obstructive sleep apnea (OSA) is one of the systemic risk factors for glaucoma which causes irreversible visual field (VF) damage. We reviewed the published data of all types of studies on the association between these two conditions and papers regarding functional and structural changes related to glaucomatous damage using Scopus, web of science, and PubMed databases. There is evidence that the prevalence of glaucoma is higher in OSA patients, which independent of intraocular pressure (IOP). Studies have reported thinning of retinal nerve fiber layer (RNFL), alteration of optic nerve head, choroidal and macular thickness, and reduced VF sensitivity in patients of OSA with no history glaucoma. A negative correlation of apnea-hypopnea index with RNFL and VF indices has been described in some studies. Raised IOP was noted which is possibly related to obesity, supine position during sleep, and raised intracranial pressure. Diurnal fluctuations of IOP show more variations in OSA patients before and after continuous positive airway pressure (CPAP) therapy when compared with the normal cases. The vascular factors behind the pathogenesis include recurrent hypoxia with increased vascular resistance, oxidative stress damage to the optic nerve. In conclusion, comprehensive glaucoma evaluation should be recommended in patients with OSA and should also periodically monitor IOP during CPAP treatment which may trigger the progression of glaucomatous damage.

[Current aspects on the management of normal tension glaucoma]

In a considerable proportion of glaucoma patients (25-50 %) the intraocular pressure (IOP) is not elevated higher than 22 mmHg at first diagnosis and during subsequent follow-up controls. Although the IOP level remains in the low range < 22 mmHg, progression of glaucoma can still occur. A multitude of different factors are assumed to be involved in glaucoma progression, such as very low nocturnal diastolic blood pressure values, a low mean ocular perfusion pressure, extensive fluctuations in perfusion (e.g. in cases of vascular dysregulation), an increased vulnerability of the optic nerve support structures, an increased translaminar pressure gradient and various underlying systemic diseases. The most important evidence-based aspect of treatment in normal tension glaucoma is pharmaceutical or surgical reduction of the IOP by 30 % or more in comparison to the initial pressure level. Vascular and neuroprotective concepts of treatment for normal tension glaucoma have been strongly advocated and the object of experimental and clinical studies. As yet a clear clinical benefit has not been proven by large prospective randomized studies.

The effect of nocturnal CPAP therapy on the intraocular pressure of patients with sleep apnea syndrome

PURPOSE

Few studies have documented that nocturnal continuous positive airway pressure (CPAP) therapy is associated with an increase in intraocular pressure (IOP) in patients with severe obstructive sleep apnea syndrome (OSAS). We re-examined the effect of CPAP therapy on the IOP of OSAS patients.

METHODS

The IOP of two different groups of newly diagnosed OSAS patients was compared at their first sleep lab exam without CPAP treatment (non-CPAP treated group; n = 20) and at the second sleep lab exam with CPAP treatment (CPAP treated group; n = 31). The sleep lab exam (sleep period: from 11:00 p.m. until 6:00 a.m.) included IOP measurements, a complete ophthalmologic exam, and nocturnal hemodynamic recordings. The IOP was measured serially using rebound tonometer (IOP; ICARE® PRO) performed while in sitting and supine positions before, during, and after the sleep period. We compared the difference in IOP of CPAP and non-CPAP groups.

RESULTS

The mean IOP of the CPAP and non-CPAP groups measured in sitting position before the sleep period was 13.33 ± 2.04 mmHg and 14.02 ± 2.44 mmHg, respectively (p = 0.9). Assuming a supine position for 1 minute significantly increased the IOP by 1.93 mmHg and 2.13 mmHg for both the non-CPAP and CPAP groups (paired t-test; p = 0.02, p = 0.001 respectively), but this IOP rise showed no difference between the two groups. The IOP increased significantly further after 7 hours of sleep in the supine position, and the mean IOP of the CPAP and non-CPAP groups was 19.2 ± 5.68 mmHg and 19.69 ± 5.61 mmHg respectively (independent t-test; p = 0.74). The rise in IOP for both groups was not correlated with any hemodynamic parameters. Three OSAS patients with glaucoma treated with CPAP had mean IOP of 23.75 mmHg after 7 hours of sleep.

CONCLUSIONS

OSAS patients have a significant rise in IOP during the sleep period when comparing measurements before and after the sleep period; however, CPAP therapy did not affect the measured IOP. The presented findings suggest that in terms of IOP, CPAP is safe for non-glaucomatous patients, but this may not hold true for glaucomatous patients.

Effect of obstructive sleep apnea syndrome on corneal thickness

Obstructive sleep apnea syndrome (OSAS) might be a risk factor for the development of eye disorders. The aim of the study was to evaluate the effect of OSAS on central corneal thickness (CCT). A total of 195 patients were enrolled in the study, and underwent polysomnography. Patients were divided according to their apnea-hypopnea index (AHI) scores into control group (AHI < 5), mild (AHI, 5-15), moderate (AHI, 15-30), and severe OSAS (AHI > 30) groups. In ophthalmological examinations, CCT, auto refractometer measurement, tear break-up time, and Schrimer's test results were evaluated. Central corneal thickness was significantly decreased in patients with OSAS compared to the control group (542.14 ± 31.21 vs. 569.92 ± 13.46, p < 0.001). As the severity of OSAS increased, CCT decreased (mild OSAS = 567.48 ± 23 mm, moderate OSAS = 530.21 ± 30.2 mm, and severe OSAS = 557.97 ± 16.52 mm, respectively, p < 0.001). The mean values of auto refractometer, tear break-up time, and Schrimer's test were similar between the groups (p > 0.05). CCT was negatively correlated with AHI, oxygen desaturation index, desaturation percentages, and positively correlated with minimum oxygen saturation values (p < 0.05). This study showed that central corneal thickness is inversely correlated with the severity of OSAS. OSAS affects all organ systems particularly cardiovascular and neurological mechanisms. Further studies are warranted to evaluate the effect of OSAS treatment on CCT.

Association between glaucoma and obstructive sleep apnea syndrome: a meta-analysis and systematic review

Background

Obstructive sleep apnea syndrome (OSAS) is a common disease that increases the risk of diabetes, heart disease, and stroke. However, studies of an association between OSAS and glaucoma neuropathy have reported controversial findings.

Objective

The main purpose of this study was to evaluate whether a significant association exists between OSAS and glaucoma by performing a meta-analysis of previous studies.

Methods

A comprehensive literature search using the PubMed and Embase databases was performed to identify cross-sectional, case-control, and cohort studies related to the topic. We estimated a pooled odds ratio (OR) for the association between OSAS and glaucoma, by a fixed- or random-effects model.

Results

In total, 16 studies with 2,278,832 participants met the inclusion criteria: one retrospective cohort study reported an adjusted hazard ratio of glaucoma of 1.67 (95% CI = 1.30–2.17). Using a fixed-effects model, the pooled OR of six case-control studies was 1.96 (95% CI = 1.37 2.80). A significant association was also identified in a meta-analysis of nine cross-sectional studies using a random-effects model, which showed a pooled OR of 1.41 (95% CI = 1.11 1.79). However, the reported pooled estimates for case control studies and cross-sectional studies were based on unadjusted ORs.

Conclusions

Our results suggest that OSAS is associated with the prevalence of glaucoma. However, this result was based only on unadjusted estimates. Prospective cohort studies designed to take into consideration potential confounders, or examination of data from interventional trials to determine whether a reduction in OSAS status is associated with a reduced incidence of glaucoma, are needed to clarify whether OSAS is an independent risk factor for glaucoma.

Obstructive sleep apnea and optic neuropathy: is there a link?

Over the last decade, there has been an emerging interest in the link between obstructive sleep apnea (OSA) and ocular health. Though the evidence for OSA playing a role in cerebrovascular disease risk seems clear, the same cannot be said for optic neuropathies. The association between OSA and glaucoma or non-arteritic anterior ischemic optic neuropathy (NAION) has been postulated to be secondary to direct hypoxia or mechanisms of optic nerve head vascular dysregulation. Papilledema and increased intracranial pressure have also been reported in OSA and are thought to be due to increased cerebral perfusion pressure and cerebral venous dilation secondary to hypoxia and hypercapnia. This article reviews the evidence for possible pathophysiological links between OSA and optic nerve pathology. The epidemiologic and clinical evidence for an association, direct or indirect, between OSA and glaucoma, non-arteritic anterior ischemic optic neuropathy (NAION), and papilledema or idiopathic intracranial hypertension is presented.

Floppy eyelid syndrome: the coventry experience

PURPOSE

Floppy eyelid syndrome is a condition that is difficult to identify and diagnose and with no clear guidelines on its management. We propose a method of reliably grading this syndrome and have proposed a management algorithm based on the grading.

MATERIALS AND METHODS

Retrospective data collection of patients diagnosed with Floppy eyelid syndrome and treated under the care of a single oculoplastic surgeon over a 9 year period.

RESULTS

First, 102 patients were included and were classified into 3 groups. Grade 1 (F1) 7.5%, Grade 2 (F2) 36.5% and Grade 3 (F3) 56%. Only 12% of our cohort required surgery, and 92% of these patients demonstrated improvement in their symptoms.

DISCUSSION

Clinical grading of Floppy eyelid syndrome patients will help determine patient's management plan. In our experience, operating on both upper and lower eyelids at the same time where indicated helps to maintain the normal anatomical relationship and improve epiphora.

Evaluation of the macular choroidal thickness using spectral optical coherence tomography in patients with obstructive sleep apnoea syndrome

BACKGROUND

To assess the choroidal thickness (CT) in patients with obstructive sleep apnoea syndrome (OSAS) and healthy controls.

DESIGN

Prospective, cross-sectional study

PARTICIPANTS

Ninety-two eyes of 92 patients with OSAS and 32 eyes of 32 aged and body mass index-matched healthy subjects were enrolled.

METHODS

OSAS patients were further divided into mild, moderate and severe OSAS groups according to their apnoea hypopnea index (AHI) values. The macular CT and peripapillary retinal nerve fibre layer (RNFL) thickness measurements of the subjects were obtained using spectral domain optical coherence tomography (RTVue-100, Optovue). The CT and RNFL thickness measurements of the groups were compared, and correlations among the AHI values and these measurements were calculated.

MAIN OUTCOME MEASURES

Choroidal thickness.

RESULTS

There were no significant differences in subfoveal and temporal CT measurements of the groups. A pairwise comparison between the groups revealed that severe OSAS group has significantly thinner CT than mild OSAS group at 3.0 mm nasal to the fovea. Also, compared with severe OSAS group, the CT measurements at 1.5 mm and 3.0 mm nasal to the fovea were significantly thicker in control eyes (both, P < 0.05). There were weak negative correlations between the nasal CT measurements and AHI in the OSAS group (nasal 1.5 mm, P = 0.002, r = -0.358; nasal 3.0 mm, P = 0.004, r = -0.336). Compared with controls, severe OSAS group had significantly thinner nasal and superior RNFL thickness measurement.

CONCLUSIONS

Sleep apnoea patients had choroidal structural alterations that may have significance on the pathophysiology of the ophthalmic disorders associated with OSAS.

Retinal nerve fiber layer thickness changes in obstructive sleep apnea syndrome: one year follow-up results

AIM

To investigate the retinal nerve fiber layer (RNFL) thickness changes in patients with obstructive sleep apnea syndrome (OSAS) for one year follow-up. To discuss the possibility of detecting tendency of glaucoma in this population by using spectral domain optical coherence tomography (3D-OCT-2000 Spectral domain).

METHODS

After polysomnographic study, all subjects (64 OSAS patients and 40 controls) underwent detailed ophthalmological examination. After these examinations, patients with glaucoma and patients who had ophthalmological and/or systemic disease were excluded from the study. Totally, 20 patients in OSAS group and five patients in controls were excluded from the study in the first examination and follow-up period. The RNFL thickness was assessed with OCT. Forty-four OSAS patients and 35 control subjects were followed up 12mo. RNFL thickness change and OSAS patients were evaluated for severity of disease by Apnea-Hypopnea Index (AHI).

RESULTS

Forty-four OSAS patients and 35 controls were enrolled in the study. Statistically significance was found between OSAS patients and controls at the 12(th) mo. Average RNFL thickness was found to be significantly lower in last measurements in OSAS patients when compared with first measurements and control subjects (P<0.001, 0.002, respectively). There was a statistically significant correlation among AHI, and RNFL thickness (P<0.05).

CONCLUSION

The results suggest that the patients with OSAS were related with a proportional decrease in the RNFL thickness. These patients should be followed up regularly for glaucomatous changes. Detecting more RNFL thinning in severe OSAS was important.

Prevalence of glaucoma in patients with moderate to severe obstructive sleep apnea: ocular morbidity and outcomes in a 3 year follow-up study

PURPOSE

This study was conducted to investigate the prevalence and progression of glaucoma in patients receiving treatment for obstructive sleep apnea (OSA). We also investigated whether there is an association between severity of OSA and the incidence of glaucoma.

METHODS

A total of 39 patients aged >30 years who had been diagnosed with moderate and severe OSA in the sleep clinic at Hamad General Hospital were assessed for the presence of glaucoma. The severity of OSA was graded as mild, moderate, or severe based on American Association of Sleep Medicine (AASM) criteria using the apnea hypopnea index. Before enrollment, all patients underwent a complete ophthalmic examination including serial visual field tests, optical coherence tomography (OCT) with fundus photographs, and pachymetry. Enrolled patients were followed up in the ophthalmology outpatient clinic and sleep clinic for a period of 3 years.

RESULTS

Examinations found that 8 (20.5%; 95% confidence interval (CI) 9.9-37%) of the 39 patients with OSA had glaucoma. Six (75%; 95% CI 36-96%) of these patients had normal-tension glaucoma (NTG) and two (25%; 95% CI 4.5-64.4%) patients had high-tension glaucoma. Among the 27 patients with severe OSA, 7 (25.9%; 95% CI 8-34%) had glaucoma, and among 12 patients with moderate OSA, 1 (8.3%; 95% CI 0.1-15%) had glaucoma. During the course of follow-up, two patients who previously did not have glaucoma were reclassified as NTG and two patients with glaucoma deteriorated. A higher prevalence of glaucoma in the severe OSA group compared with the moderate OSA group was found, albeit a statistically significant difference could not be attained (P=0.4).

CONCLUSIONS

Our study showed that severe OSA is an important risk factor for developing glaucoma. Adequate treatment of OSA, along with optimal ophthalmic care, resulted in better control of glaucoma.

Obstructive sleep apnea patients having surgery are less associated with glaucoma

Objective. To investigate if different treatment strategy of obstructive sleep apnea (OSA) was associated glaucoma risk in Taiwanese population. Methods. Population-based retrospective cohort study was conducted using data sourced from the Longitudinal Health Insurance Database 2000. We included 2528 OSA patients and randomly selected and matched 10112 subjects without OSA as the control cohort. The risk of glaucoma in OSA patients was investigated based on the managements of OSA (without treatment, with surgery, with continuous positive airway pressure (CPAP) treatment, and with multiple modalities). The multivariable Cox regression was used to estimate hazard ratio (HR) after adjusting for sex, age, hypertension, diabetes, hyperlipidemia, and coronary artery disease. Results. The adjusted HR of glaucoma for OSA patients was 1.88 (95% CI: 1.46–2.42), compared with controls. For patients without treatment, the adjusted HR was 2.15 (95% CI: 1.60–2.88). For patients with treatments, the adjusted HRs of glaucoma were not significantly different from controls, except for those with CPAP (adjusted HR = 1.65, 95% CI = 1.09–2.49). Conclusions. OSA is associated with an increased risk of glaucoma. However, surgery reduces slightly the glaucoma hazard for OSA patients.

Increased risk of open-angle glaucoma following chronic rhinosinusitis: a population-based matched-cohort study

PURPOSE

Anatomically, the eyes and paranasal sinuses are neighboring structures and some studies have mentioned eye disease in conjunction with chronic rhinosinusitis (CRS). However, to the best of our knowledge, no prior research has investigated the risk of developing open-angle glaucoma (OAG) among CRS patients. This study aims to provide an estimated risk of developing OAG among patients with CRS by using a population-based data set in Taiwan.

METHODS

This retrospective cohort study used data sourced from the 'Longitudinal Health Insurance Database 2000'. A total of 15,642 CRS patients were included in the study cohort and 46,926 subjects were randomly extracted as a comparison cohort. A cox proportional-hazards regression analysis was performed to calculate the 5-year risk of subsequently developing OAG following a diagnosis of CRS between the study cohort and the comparison cohort.

RESULTS

The incidence rate of developing OAG over the 5-year follow-up period was 5.45 (95% CI: 4.95-5.98) per 1000 person-years for the study cohort and 2.80 (95% CI: 2.60-3.03) per 1000 person-years for the comparison cohort. After censoring the cases that died over the 5-year period and adjusting for the factors of monthly income, geographic region, hypertension, diabetes, coronary heart disease, hyperlipidemia, and hypothyroidism the hazard ratio for developing OAG over the 5-year period for subjects with CRS to subjects without CRS was 1.73 (95% CI: 1.53-1.96).

CONCLUSION

We found that those subjects with CRS had a significantly higher risk of developing OAG over the 5-year follow-up period as compared with subjects without CRS.

Optic disc and retinal nerve fiber layer parameters as indicators of neurodegenerative brain changes in patients with obstructive sleep apnea syndrome

PURPOSE

Retina is a unique part of the central nervous system (CNS) for visualizing the processes of axonal and neuronal degeneration. Optical coherence tomography (OCT) allows direct visualization and measurement of retinal nerve fiber layer (RNFL) thickness, macular volume, and optic disc (OD) parameters. One of the disorders associated with atrophy in different brain regions is obstructive sleep apnea syndrome (OSAS). In the present study, we aimed to determine OD and RNFL changes measured by OCT for investigating the progress of neurodegeneration development in OSAS, excluding all the other conditions that can directly affect RNFL thickness and optic nerve parameters.

METHODS

Both eyes of 101 patients with OSAS and 20 controls were investigated by OCT. Full-night polysomnography (PSG) and ophthalmologic examination including automated visual field (VF) examination and OCT were performed in all of the patients.

RESULTS

According to the OSAS grading, patients were grouped as mild (n=15), moderate (n=27), and severe (n=59). We found significant decrease in RNFL thickness only in the patients with severe OSAS compared with the other groups and decreased macular ganglion cell thickness in the severe OSAS group compared with the control group. VF parameters were significantly worsened in all the OSAS subgroups compared to the control group. We found different data such as normal or increased optic nerve parameters as result of subtle OD edema, which may mask possible peripapillar axonal loss.

CONCLUSIONS

We think that evaluation of neurodegeneration in OSAS is not always possible by examining OD and RNFL because there are difficulties due to the confounding issues of cerebral atrophy and OD edema.