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

Effect of Sleeping Position on the Retinal Nerve Fiber Layer in Individuals with Glaucoma

Aims and background

To evaluate the effect of sleeping in the lateral decubitus position on the average thickness of the retinal nerve fiber layer (RNFL) in the peripapillary region of the optic nerve since the effect of posture on intraocular pressure (IOP) and glaucoma progression is not yet sufficiently understood.

Materials and methods

A cross-sectional observational study was carried out with 40 volunteers who preferably slept in a right lateral decubitus (RLD) (RLD group N = 20) and left lateral decubitus (LLD) (LLD group N = 20) position. IOP was measured in both eyes, first in the sitting position and again after 10 minutes in a supine position, right lateral, and LLD, respectively. The mean thickness of the RNFL and the vertical papillary cup were measured by optical coherence tomography.

Results

The average age of the volunteers was 60.53 ± 7.26 years. There were 32 female and eight male. There was an increase in IOP with the change from the sitting position to the lateral decubitus of 2.7 and 3.6 mm Hg in the RLD group (p < 0.001) and an increase of 3.0 and 3.15 mm Hg in the LLD group (p < 0.001), right eye (RE) vs left eye (LE), respectively. However, there was no difference in IOP values between the groups. The average thickness of the RNFL was in the RLD group-75.10 vs 78.05 μm (p = 0.325) and in the LLD group-81.55 vs 79.95 μm (p = 0.580). Vertical papillary excavation was in the RLD group-0.70 vs 0.65 (p = 0.175) and in the LLD group-0.65 vs 0.65 (p = 1.000), RE vs LE, respectively.

Conclusion

We found no relationship between the lateral decubitus position when adopted preferentially for sleeping and the reduction of the RNFL.

Clinical significance

Search for risk factors for the asymmetrical development of glaucoma, especially in well-controlled IOP in daytime measurements.

How to cite this article

Vaz RT, Montenegro AAL, Quintas Segundo ADS, et al. Effect of Sleeping Position on the Retinal Nerve Fiber Layer in Individuals with Glaucoma. J Curr Glaucoma Pract 2024;18(2):57-62.

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.

Association of sleep behaviour and pattern with the risk of glaucoma: a prospective cohort study in the UK Biobank

OBJECTIVES

Given the role of intraocular pressure in glaucoma, the patient's sleeping pattern might contribute to the development and progression of glaucoma. We performed a study to understand the association between sleep behaviours and glaucoma.

DESIGN

Our study was a prospective cohort study.

SETTING

This was a prospective cohort study in the UK Biobank. Self-reported data on five sleep behaviours were collected using a questionnaire at baseline. We identified four sleep patterns based on a cluster analysis of the sleep behaviours.

PARTICIPANTS

In the UK Biobank, 409 053 participants were recruited between 2006 and 2010 and followed for a diagnosis of glaucoma. We identified glaucoma as any hospital admission with a diagnosis of glaucoma, based on UK Biobank inpatient hospital data. Individuals who withdrew from the UK Biobank, or were diagnosed with glaucoma before recruitment, or had self-reported surgery or laser treatment for glaucoma, or had no information on sleep behaviors were excluded.

PRIMARY AND SECONDARY OUTCOME MEASURES

We estimated hazard ratios (HRs) with 95% confidence intervals (CI) using Cox proportional hazards models to estimate the associations of different sleep behaviors, as well as identified sleep patterns, with the risk of glaucoma, adjusting for multiple confounders.

RESULTS

Compared with individuals who had a healthy sleep pattern, an excess risk of any glaucoma was observed among individuals with snoring and daytime sleepiness (HR 1.11, 95% CI 1.03 to 1.19) or insomnia and short/long sleep duration (HR 1.13, 95% CI 1.06 to 1.20), but not late chronotype sleep pattern (HR 0.98, 95% CI 0.93 to 1.03).

CONCLUSION

Snoring, daytime sleepiness, insomnia, and short/long duration, individually or jointly, were all associated with the risk of glaucoma. These findings underscore the need for sleep intervention for individuals at high risk of glaucoma as well as potential ophthalmologic screening among individuals with chronic sleep problems for glaucoma prevention.

A Narrative Review of the Association between Obstructive Sleep Apnea and Glaucoma in Adults

BACKGROUND

Obstructive sleep apnea (OSA) is a sleep disorder, primarily of the upper airway, which not only has a significant impact on quality of life but is also associated with various systemic diseases. Several ophthalmological diseases are also associated with OSA, especially glaucoma. The purpose of this review is to take a closer look at the causality and mutual influence.

METHODS

A systematic literature search was conducted using PubMed. A total of 19 studies with 316,178 adult participants were included.

RESULTS

Eleven of the sixteen studies concentrating on the prevalence of glaucoma in patients with OSA showed an association of both entities. One paper found a higher risk for progression of glaucoma in OSA patients. Five of the sixteen included studies failed to show a correlation between OSA and glaucoma. One study out of three surveying specific ophthalmological parameters showed an influence of OSA therapy on retinal nerve fiber layer (RNFL) thinning and vision. One study showed a rise in intraocular pressure (IOP), while two other studies showed no increase under continuous positive airway pressure (CPAP).

CONCLUSIONS

Our findings suggest an association between OSA and glaucoma and, especially, between OSA and thinning of RNFL. CPAP therapy appears to be also suitable for patients with comorbid glaucoma.

Research on the Association Between Obstructive Sleep Apnea Hypopnea Syndrome Complicated With Coronary Heart Disease and Inflammatory Factors, Glycolipid Metabolism, Obesity, and Insulin Resistance

The aim of this study is to explore the association between obstructive sleep apnea hypopnea syndrome (OSAHS) complicated with coronary heart disease (CHD) and inflammatory factors, glycolipid metabolism, obesity, and insulin resistance. A total of 400 patients diagnosed with OSAHS who underwent polysomnography (PSG) monitoring in the Sleep Diagnosis and Treatment Center of Beijing Luhe Hospital from March 2015 to September 2018 were selected and divided into the OSAHS group (n = 200) and the OSAHS + CHD group (n = 200) according to disease condition. The questionnaire survey was conducted, the somatology indexes were measured, and the PSG, insulin, glycolipid metabolism parameters, and serum inflammatory factors were detected. Body weight, body mass index, waist circumference, and Epworth sleepiness scale (ESS) score were all significantly increased in the OSAHS + CHD group compared with those in the OSAHS group (p < 0.05). The microarousal index (MAI), apnea hypopnea index (AHI), cumulative percentage of time spent at oxygen saturation below 90% (CT90%), oxygen desaturation index (ODI), lowest oxygen saturation (LSaO₂), total apnea time (TAT), and mean oxygen saturation (MSaO₂) had statistically significant differences between the OSAHS + CHD group and the OSAHS group (p < 0.05). According to the Spearman correlation analysis of AHI, LSaO₂, MSaO₂, CT90%, ODI, and MAI with HOMA-IR in both groups, MAI, AHI, CT90%, and ODI were positively correlated with HOMA-IR (r > 0), while LSaO₂ and MSaO₂ were negatively correlated with HOMA-IR (r < 0). Compared with the OSAHS group, the OSAHS + CHD group had an obviously increased level of triglyceride (TG) (p < 0.05), and obviously increased levels of serum inflammatory factors C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interferon-γ (IFN-γ) (p < 0.05). The occurrence of OSAHS complicated with CHD is related to inflammatory factors, glycolipid metabolism, obesity rate, and HOMA-IR.

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.

24-h intraocular pressure patterns measured by Icare PRO rebound in habitual position of open-angle glaucoma eyes

PURPOSE

To measure the 24-h intraocular pressure (IOP) by Icare PRO rebound in healthy and primary open-angle glaucoma (POAG) eyes and compare it with non-contact tonometry (NCT).

METHODS

Thirty POAG patients, who were under IOP-lowering treatment, and 30 healthy subjects were included. Participants were hospitalized overnight for the 24-h IOP measurement. IOPs were measured by Icare PRO and NCT according to a standard protocol every 2 h during 24 h. The 24-h IOP curve and IOP-related parameters were compared between Icare PRO and NCT groups in POAG and healthy eyes.

RESULTS

The IOPs measured by Icare PRO in habitual position increased notably at 22:00 in the normal group and at 20:00 in the POAG group, reached peak at 0:00, stayed high until 4:00, and then decreased in both groups (all p < 0.05). The POAG patients had higher mean 24-h IOP, peak IOP, IOP fluctuation, and greater IOP change from supine to sitting position in the nocturnal period than those in the normal subjects even after adjusting for eyes, age, gender, CCT, and axial length (all p < 0.05).

CONCLUSIONS

The Icare PRO provides a well-tolerated approach for 24-h IOP monitoring in habitual position. Twenty-four-hour IOP in habitual position is more sensitive for detecting high nocturnal IOP peaks and greater IOP fluctuation for POAG patients.

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.

Intraocular pressure response affected by changing of sitting and supine positions

PURPOSE

To assess the intraocular pressure (IOP) time response to change in body position from sitting to supine and from supine to sitting immediately and during rest in each position.

METHODS

Forty-four visually healthy volunteers were recruited for the study. The experiment consisted of the initial sitting position (baseline state), the subsequent lying period and the final sitting period. Both periods were 30 min long. The IOP was measured in the baseline state, immediately after each position change and then in minutes 5, 15, 25 and 30 during each period. The Icare Pro^® rebound tonometer was used.

RESULTS

The mean IOP increased after each position change (2.6 ± 2.4 mmHg after lying down and 2.1 ± 3.1 mmHg after sitting up) and then gradually decreased with time. The mean IOP was 1.41 ± 2.4 mmHg higher in the lying period than in the sitting period; the mean difference was smaller for the lower baseline (0.9 ± 2.2 mmHg) than the higher baseline (1.9 ± 2.5 mmHg). The mean IOP in the final sitting was significantly lower (2.5 ± 1.9 mmHg) than in the initial sitting position. The effect of sex was insignificant.

CONCLUSIONS

There was an immediate increase in IOP as a response to both changes in the body position and the subsequent gradual decrease with time. The IOP difference between lying and sitting position was depended on baseline.

Upside-down position leads to choroidal expansion and anterior chamber shallowing: OCT study

Background

To determine whether dynamic changes in choroidal thickness (CT) cause shallowing of the anterior chamber.

Methods

34 healthy volunteers were enrolled. The participants in our study adopted the upside-down position for 1.5 min, which was the model we used to study the dynamic changes in CT. Intraocular pressure (IOP) elevation, optical coherence tomography images of the choroid and anterior chamber were obtained at baseline, after being in an upside-down position in an inversion machine and after 15 min of rest. The changes in IOP, anterior chamber and choroidal blood flow between the baseline and the upside-down position were compared.

Results

Sixty-eight eyes from 34 subjects were analysed. After being in upside-down position for 1.5 min, there was a significant increase in CT from 226.39±52.44 µm to 238.34±54.84 µm (p<0.001). Choroidal flow index decreased from 0.3357±0.0251 to 0.3004±0.0190 in upside-down position, and there was a decrease in anterior chamber depth (3.21±0.22 mm to 3.13±0.21 mm, p<0.001) and angle opening distance at 500 µm from the scleral spur (0.65±0.24 mm to 0.58±0.20 mm, p=0.007). Pearson correlation analysis showed that the increase in CT was positively related with CT at baseline CT (p=0.001).

Conclusion

When the body position changed from sitting to upside-down position, there was choroidal thickening, anterior chamber shallowing and IOP elevation with reduced choroidal blood flow. The data provide evidence about the relationship between choroid expansion and shallowing of the anterior chamber, which may be of relevance for the pathogenesis of angle closure.

Perioperative considerations and anesthesia management in patients with obstructive sleep apnea undergoing ophthalmic surgery

Obstructive sleep apnea (OSA) is a disorder characterized by breathing cessation caused by obstruction of the upper airway during sleep. It is associated with multiorgan comorbidities such as obesity, hypertension, heart failure, arrhythmias, diabetes mellitus, and stroke. Patients with OSA have an increased prevalence of ophthalmic disorders such as cataract, glaucoma, central serous retinopathy (detachment of retina, macular hole), eyelid laxity, keratoconus, and nonarteritic anterior ischemic optic neuropathy; and some might require surgery. Given that OSA is associated with a high incidence of perioperative complications and more than 80% of surgical patients with OSA are unrecognized, all surgical patients should be screened for OSA (eg, STOP-Bang questionnaire) with comorbidities identified. Patients suspected or diagnosed with OSA scheduled for ophthalmic surgery should have their comorbid conditions optimized. This article includes a review of the literature and highlights best perioperative anesthesia practices in the management of ophthalmic surgical patients with OSA.

The possible impact of cervical stenosis on cephalad neuronal dysfunction

Earlier observers have speculated on the causal relationships between abnormal CSF circulation and a variety of neurological dysfunctions. Such speculations have been at least partially validated by recent evidence and inquiries contravening the traditional static viewpoint of CSF circulation. More contemporary inquiries establish a number of factors which influence both CSF production and absorption (sleep disturbance, neck position, cerebral metabolism, brain atrophy, medications, etc.). Thus, transient periods of abnormality are possibly mingled with periods of normality. Such episodic alterations suggest that the physiological arrangements which underpin CSF circulation may be in some ways likened to blood pressure alterations, in that long-standing CSF abnormalities may be both unappreciated and gradual, though virulent enough to cause substantial neurological injury. We suggest that cervical stenosis (blocking an important CSF decompressive pathway into the vertebral canal) is among the largely unappreciated causes of abnormal CSF circulation and may play a role in cephalad neuronal dysfunction. Such a blockage is correlated with age and easily assessed by cine MRI study. Indeed, episodic disturbances can diminish CSF cerebral flow circulation increasing deposition in cerebral parenchyma of contrary metabolic products (e.g. beta Amyloid), possibly having a causal influence on senile dementia. Additionally, cervical stenosis, by increasing posterior fossa cerebral pressure, could play a causal role in a number of afflictions, among them sleep apnea, concomitant respiratory and circulatory dysfunction, hypertension, chronic occipital headaches, tinnitus, etc. We further suggest that among those patients with substantial cervical stenosis (extensive enough to block CSF circulation in the cervical area as identified by cine MRI) appropriate comparative clinical studies could be undertaken to demarcate associations with presenile dementia, sleep disturbance and posterior fossa dysfunction. Additionally, we suggest that an intracranial monitoring implant be perfected to chronically monitor both intracranial pressure and CSF flow - a monitoring device comparable to the rather less invasive sphygmometric evaluation of blood pressure. If such speculations prove correct, different therapeutic regimens which might improve outcome could be imagined. Among them better sleep hygiene (to by position maximize CSF flow) and possibly more aggressive operative decompressive intervention to diminish cervical obstruction.