The association of blood pressure and primary open-angle glaucoma: a meta-analysis

Effect of a Collar and Harness on Intraocular Pressure and Respiration Rate of Brachycephalic and Dolichocephalic Dogs

BACKGROUND

Dogs are a popular pet in many countries, and for them to gain appropriate exercise, many owners opt to walk them on a leash. Despite health and welfare concerns, brachycephalic breeds remain common as pets, with limited research existing that investigates the best restraint type for these animals.

OBJECTIVES

This study aimed to test the effect of a collar and harness during stationary and exercise conditions on the intra-ocular pressure (IOP) and respiration rate (RR) of brachycephalic and dolichocephalic dogs.

METHODS

A total of 24 healthy dogs, both brachycephalic and dolichocephalic, were recruited for the study and underwent stationary and exercise conditions in two restraint types in a within-between-subjects design. IOP was measured by rebound tonometry, and RR was measured using clinical and visual methods by the same experimenter.

RESULTS

Just wearing a collar in a stationary condition increased IOP in brachycephalic dogs (p < 0.05) but not in dolichocephalic dogs (p > 0.05). Exercising in a collar increased IOP for both groups of dogs (p < 0.05), whereas exercising in a harness did not affect IOP for either group (p > 0.05). RR increased in exercise conditions for both restraint types in brachycephalic dogs (p < 0.05), with no difference between collar and harness (p > 0.05).

CONCLUSIONS

Data suggest that collars may elevate IOP during exercise for all dogs and also during stationary conditions for brachycephalic breeds. Owners need to be conscious of the most appropriate restraint for their dog to avoid deleterious effects on IOP and RR.

Exploring the effect of SGLT2 inhibitors on the risk of primary open-angle glaucoma using Mendelian randomization analysis

This study aimed to evaluate the causal effect of sodium-glucose cotransporter protein 2 (SGLT2) inhibition on primary open-angle glaucoma (POAG) and explore potential mechanisms. A drug-targeted Mendelian randomization (MR) study was conducted using genetic variation related to SGLT2 inhibition, based on SGLT2 gene expression and glycated hemoglobin levels. Genetic summary statistics for POAG were obtained from the FinnGen consortium and a multi-ancestry genome-wide association study. Glaucomatous endophenotype data were also incorporated. A two-step MR analysis was performed to examine whether pathways related to obesity, blood pressure, lipid levels, oxidative stress, and inflammation mediated the association between SGLT2 inhibition and POAG. Genetically predicted SGLT2 inhibition was associated with a reduced risk of POAG (OR: 0.28; 95% CI: 0.12 to 0.63; P = 2.22 × 10- 3), confirmed in a multi-ancestry validation cohort. It was also associated with decreased optic cup area, reduced vertical cup-disc ratio, and increased optic disc area. Mediation analysis indicated that the effect of SGLT2 inhibition on POAG was partly mediated by diastolic blood pressure (4.8%). This study suggests that SGLT2 inhibition is a promising therapeutic target for POAG. However, further large-scale randomized controlled trials are required to confirm these findings.

Predictive modeling of rapid glaucoma progression based on systemic data from electronic medical records

This study investigated the baseline systemic features that predict rapid thinning of the retinal nerve fiber layer (RNFL) in patients with primary open-angle glaucoma (POAG). A database drawn from electronic medical records (EMRs) was searched for patients diagnosed with POAG between 2009 and 2016 who had been followed up for > 5 years with the annual evaluation of global RNFL thickness using spectral-domain optical coherence tomography. The rate of change in global RNFL thickness for each eye was determined by linear regression analysis over time. Systemic data obtained within 6 months from the time of glaucoma diagnosis were extracted from the EMRs and incorporated into a model to predict the rate of progressive RNFL thinning. The predictive model was trained and tested using a random forest (RF) method and interpreted using Shapley additive explanation plots (SHAP). The features able to explain the rate of progressive RNFL thinning were identified and interpreted. Data from 1256 eyes of 696 patients and 1107 eyes of 607 patients were included in the training and test sets, respectively. The R2 value for the RF model was 0.88 and mean absolute error of the model was 0.205 μm/year. The prediction model identified higher serum levels of aspartate aminotransferase, lower blood glucose, lower systolic blood pressure, and higher high-density lipoprotein as the four most important systemic features predicting rapid RNFL thinning over 5 years. Among the ophthalmic features, a higher global RNFL thickness and a higher intraocular pressure were the most important factors predicting rapid RNFL thinning. The study revealed baseline systemic features from the EMRs that were of predictive value for progression rate of POAG patients.

Heart Rate Variability Time-Domain Analysis Across Glaucoma Subtypes

Background/Objectives: The association between glaucoma and autonomic nervous system (ANS) function remains unclear. Primary open-angle glaucoma (POAG) and exfoliation glaucoma (EXG) have distinct pathophysiological mechanisms, which may lead to different ANS alteration. This study aimed to investigate the association between different glaucoma subtypes and the following time-domain heart rate variability (HRV) parameters: the standard deviation of normal-to-normal intervals (SDNN), the square root of the mean of the sum of the squared differences between adjacent normal-to-normal intervals (RMSSD), and the coefficient of variation of R-R intervals (CVRR). Methods: A total of 809 eyes from 809 patients with POAG, EXG, and controls were included. HRV was measured from the participants' fingertips using a sphygmograph (TAS9 Pulse Analyzer Plus View; YKC Corp., Tokyo, Japan). Comparisons of time-domain HRV parameters among the groups were conducted. To evaluate the associations between time-domain HRV parameters and other variables, linear regression analyses were conducted. Results: This study included 522 participants with POAG, 191 participants with EXG, and 96 participants in the control group. There was a significant difference in CVRR among the groups (the control group: 4.04 ± 2.08%, the POAG group: 3.86 ± 1.87%, the EXG group: 3.57 ± 2.02%; p = 0.010), whereas no significant differences were found in SDNN and RMSSD. The EXG group had significantly lower values of SDNN and CVRR values compared to the POAG group (p = 0.0156 and p = 0.0037, respectively). In multivariate linear regression analysis, the highest recorded intraocular pressure (IOP) was significantly associated with CVRR. Conclusions: HRV parameters may reflect ANS alterations in glaucoma subtypes.

Impact of Physiological and Psychological Stress on Glaucoma Development and Progression: A Narrative Review

Glaucoma is a leading cause of irreversible blindness worldwide. Presently, elevated intraocular pressure (IOP) is the only approved modifiable risk factor. A consensus of the current literature suggests that both physiological and psychological stress may also impact the lifelong course of glaucoma. Specifically, stress is known to influence sympathetic nervous system activity. An increase in sympathetic nervous system activity may elevate a person's blood pressure (BP) and IOP, and both are strongly associated with glaucomatous disease. Anxiety and depression have more conflicting evidence in relation to glaucoma. Socioeconomic and environmental stress may worsen adherence to therapy and disease outcomes due to a lack of financial resources and related access to healthcare. Neighborhood quality and environmental conditions, particularly urban environments, have been associated with glaucoma risk factors, higher glaucoma prevalence, and delayed surgical interventions. Racial differences have also been identified, with Black patients being more stressed and likely to present with increased glaucoma severity and faster disease progression than White patients. Mindfulness, meditation, and other forms of psychological relaxation have been shown to reduce IOP and stress biomarkers and result in improved quality of life (QOL). Larger studies in more diverse populations are needed to clarify risk and identify the best therapeutic approaches to reduce stress as a method to improve clinical outcomes and QOL for glaucoma patients.

Stimulus-driven cerebrospinal fluid dynamics is impaired in glaucoma patients

Cerebrospinal fluid (CSF) dynamics, driven by sensory stimulation-induced neuronal activity, is crucial for maintaining homeostasis and clearing metabolic waste. However, it remains unclear whether such CSF flow is impaired in age-related neurodegenerative diseases of the visual system. This study addresses this gap by examining CSF flow during visual stimulation in glaucoma patients and healthy older adults using functional magnetic resonance imaging. The findings reveal that in glaucoma, CSF inflow becomes decoupled from visually evoked blood-oxygenation-level-dependent (BOLD) response. Furthermore, stimulus-locked CSF patterns, characterized by decreases following stimulus onset and increases after offset, diminish as glaucoma severity worsens. Mediation analysis suggests that this flattened CSF pattern is driven by a flatter BOLD slope, resulting in a shallower CSF trough and a reduced rebound. These findings unveil a novel pathophysiological mechanism underlying disrupted stimulation-driven CSF dynamics in glaucoma and highlight potential in vivo biomarkers for monitoring CSF in the glaucomatous brain.

Interplay Between Ocular Ischemia and Glaucoma: An Update

Glaucoma is a main cause of irreversible blindness worldwide, with a high impact on productivity and quality of life. The mechanical and ischemic theories are currently the most recognized pathophysiological pathways that explain the neurodegeneration of retinal nerve fibers in glaucoma. In this narrative review, aspects of ischemia in glaucoma are discussed, including vascular dysregulation, retinal ischemia signaling pathways, roles of vascular endothelial growth factors, and future research and therapeutic directions. In conclusion, a better understanding of the ischemic processes in glaucoma may lead to innovative treatment options and improved management and follow-up of our patients.

Global incidence and risk factors for glaucoma: A systematic review and meta-analysis of prospective studies

Background

This study aims to estimate global incidence and assess risk factors for glaucoma subtypes.

Methods

The literature search was performed in three English (PubMed, Embase, MEDLINE) and three Chinese (China National Knowledge Infrastructure, Wanfang, China Science and Technology Journal Database) databases to identify prospective studies on glaucoma incidence between 1 January 1990 and 29 November 2022. We used a multilevel mixed-effects meta-regression to estimate the age- and sex-specific incidence rate of primary open-angle glaucoma (POAG). The global and regional incidence rate of POAG in 2022 were respectively estimated. The annual cumulative incidence (ACI) of POAG and primary angle-closure glaucoma (PACG), and risk factors for POAG were pooled using a random-effects meta-analysis, respectively. The heterogeneity of the included articles was tested using the Q statistic and measured by I2 index. Publication bias was detected by funnel plots, Egger's regression test, and Begg's rank correlation test.

Results

A total of 9050 articles were identified in literature search, and 50 articles provided incidence data of glaucoma subtypes. In 2022, the global incidence rate of POAG was 23.46 (95% confidence interval (CI) = 15.68-32.91) per 10 000 person-years among 40-79 years. An increase from 5.51 (95% CI = 1.63-11.12) per 10 000 person-years in 40-44 years to 64.36 (95% CI = 49.82-80.70) per 10 000 person-years in 75-79 years was noted between the year 1990 and 2019. Across sociodemographic index (SDI) and World Health Organization (WHO) regions, the incidence rate was the highest in low SDI region and Africa, respectively. The pooled ACI of POAG was 0.21% (95% CI = 0.13%-0.30%). Six risk factors for POAG were identified, including intraocular pressure (IOP) treatment (meta-odds ratio (OR) = 3.69; 95% CI = 2.64-5.15), a family history of glaucoma (meta-OR = 2.49; 95% CI = 1.92-3.24), myopia (meta-OR = 2.08; 95% CI = 1.59-2.70), elevated IOP (meta-OR = 1.13; 95% CI = 1.11-1.15), advanced age (meta-OR = 1.07; 95% CI = 1.05-1.08), male (female: meta-OR = 0.76; 95% CI = 0.66-0.88). The pooled ACI of PACG was 0.05% (95% CI = 0.00%-0.16%).

Conclusions

Significant disparities existed in incidence rates for glaucoma across geographic regions and age groups. Further research is needed to understand which risk factors drive glaucoma incidence in different socioeconomic strata for tailored health policy on preventing glaucoma.

Registration

This study is registered with PROSPERO (number CRD42023434203).

Glaucoma and dietary links: insights from high-salt intake, the Mediterranean diet, and specific nutrients

Glaucoma, a prevalent and potentially blinding eye disease, is linked to a variety of factors, including elevated intraocular pressure, optic nerve damage, and oxidative stress. In recent years, dietary habits, as a controllable lifestyle factor, have received increasing attention in the prevention and treatment of glaucoma. The purpose of this review was to investigate the effects of dietary factors on glaucoma, with a particular emphasis on two common dietary patterns: the high-salt diet and the Mediterranean diet. In addition, we investigated the association between many particular nutrients (including omega-3 fatty acids, vitamins, caffeine, and minerals) and glaucoma to fully assess the potential involvement of dietary variables in glaucoma pathogenesis, prevention, and treatment. This article reveals the importance of dietary components in glaucoma prevention and explores prospective possibilities for future research by conducting a comprehensive review of previous scientific studies.

The Association of Urinary Sodium Excretion with Glaucoma and Related Traits in a Large United Kingdom Population

PURPOSE

Excessive dietary sodium intake has known adverse effects on intravascular fluid volume and systemic blood pressure, which may influence intraocular pressure (IOP) and glaucoma risk. This study aimed to assess the association of urinary sodium excretion, a biomarker of dietary intake, with glaucoma and related traits, and determine whether this relationship is modified by genetic susceptibility to disease.

DESIGN

Cross-sectional observational and gene-environment interaction analyses in the population-based UK Biobank study.

PARTICIPANTS

Up to 103 634 individuals (mean age: 57 years; 51% women) with complete urinary, ocular, and covariable data.

METHODS

Urine sodium:creatinine ratio (UNa:Cr; mmol:mmol) was calculated from a midstream urine sample. Ocular parameters were measured as part of a comprehensive eye examination, and glaucoma case ascertainment was through a combination of self-report and linked national hospital records. Genetic susceptibility to glaucoma was calculated based on a glaucoma polygenic risk score comprising 2673 common genetic variants. Multivariable linear and logistic regression, adjusted for key sociodemographic, medical, anthropometric, and lifestyle factors, were used to model associations and gene-environment interactions.

MAIN OUTCOME MEASURES

Corneal-compensated IOP, OCT derived macular retinal nerve fiber layer and ganglion cell-inner plexiform layer (GCIPL) thickness, and prevalent glaucoma.

RESULTS

In maximally adjusted regression models, a 1 standard deviation increase in UNa:Cr was associated with higher IOP (0.14 mmHg; 95% confidence interval [CI], 0.12-0.17; P < 0.001) and greater prevalence of glaucoma (odds ratio, 1.11; 95% CI, 1.07-1.14; P < 0.001) but not macular retinal nerve fiber layer or ganglion cell-inner plexiform layer thickness. Compared with those with UNa:Cr in the lowest quintile, those in the highest quintile had significantly higher IOP (0.45 mmHg; 95% CI, 0.36-0.53, P < 0.001) and prevalence of glaucoma (odds ratio, 1.30; 95% CI, 1.17-1.45; P < 0.001). Stronger associations with glaucoma (P interaction = 0.001) were noted in participants with a higher glaucoma polygenic risk score.

CONCLUSIONS

Urinary sodium excretion, a biomarker of dietary intake, may represent an important modifiable risk factor for glaucoma, especially in individuals at high underlying genetic risk. These findings warrant further investigation because they may have important clinical and public health implications.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Long-Term Systemic Use of Calcium Channel Blockers and Incidence of Primary Open-Angle Glaucoma

PURPOSE

To evaluate the association between the systemic use of calcium channel blockers (CCBs) and primary open-angle glaucoma (POAG) using a diverse nationwide dataset.

DESIGN

Retrospective cohort study.

SUBJECTS

213 424 individuals aged 40 years and older in the National Institutes of Health All of Us dataset, notable for its demographic, geographic, and medical diversity and inclusion of historically underrepresented populations. Patients with a diagnosis of POAG prior to use of any kind of antihypertensive medication were excluded.

METHODS

Bivariate and multivariable regression analyses were performed to evaluate associations between CCB use and POAG. Calcium channel blocker use was further divided into exposure to dihydropyridine CCBs and nondihydropyridine CCBs, and subgroup analyses were performed using chi-square and Fisher tests.

MAIN OUTCOME MEASURES

Diagnosis of POAG.

RESULTS

Within our cohort, 2772 participants (1.3%) acquired a diagnosis of POAG, while 210 652 (98.7%) did not. Among patients who developed POAG, the mean age was 73.3 years, 52.5% were female, and 48.2% identified as White. Among patients with POAG, 32.6% used 1 or more CCB, 28.2% used a dihydropyridine CCB, and 2.2% used a nondihydropyridine CCB. In bivariate analysis, use of any CCBs was associated with an increased risk of POAG (odds ratio [OR]: 1.29, 95% confidence interval [CI]: 1.27-1.31, P < 0.001). In multivariable analysis adjusting for age, gender, race, ethnicity, and comorbidities such as diabetes, hyperlipidemia, and hypertension, use of any CCBs remained associated with an increased risk of developing POAG (OR: 1.52, 95% CI: 1.33-1.74, P < 0.001). When stratified by type of CCB, the use of dihydropyridine CCBs (OR: 1.31, 95% CI: 1.14-1.50, P < 0.001) was associated with increased POAG risk.

CONCLUSIONS

Use of dihydropyridine CCBs was associated with a significantly higher risk of developing POAG, both before and while adjusting for demographic factors and comorbid medical conditions.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Association of Age of Menopause and Glaucoma Diagnosis in Female Veterans

Purpose

Age of menopause has been associated with the risk of developing glaucoma; however, it is unclear if the onset of menopause is directly associated with the development of glaucoma. Our objective was to determine if there is an association between the age at diagnosis of menopause and glaucoma.

Methods

This retrospective, case-only analysis was performed using the Veterans Affairs (VA) Corporate Data Warehouse of female veterans from 2000 to 2019. Women with both menopause and glaucoma diagnoses were matched based on covariates. The two matched cohorts were early menopause-early comparative (EM-EC; n = 1075) and late menopause-late comparative (LM-LC; n = 1050) women. We used a Pearson correlation to examine the linear relationship between age at diagnosis of menopause and glaucoma. Afterward, we used a multivariate linear regression model with age at diagnosis of glaucoma serving as the outcome variable to account for the covariates.

Results

We found that EM women developed glaucoma 6.0 years (interquartile range [IQR], 5.1-6.5) earlier than the EC group (P < 0.001), and LM women developed glaucoma an average of 5.2 years (IQR, 4.8-5.7) later than the LC group (P < 0.001). There was a modest linear relationship between the age of menopause and glaucoma diagnoses in the EM-EC (r = 0.40) and LM-LC (r = 0.46) cohorts. In our multivariate analysis, age at diagnosis of menopause was the largest factor related to age at diagnosis of glaucoma while accounting for our covariates. Our models predicted a 0.67-year delay in age at diagnosis of glaucoma with each additional premenopausal year.

Conclusions

This case-only analysis elucidates a temporal association between menopause and glaucoma, highlighting the need to characterize the role of menopause in the onset of glaucoma for women.

Epidemiology and Treatment of Patients With Primary Open Angle Glaucoma in Germany: A Health Claims Data Analysis

PRCIS

Based on a large administrative database of German claims data, our study provides current estimates of the prevalence and incidence of primary open angle glaucoma (POAG) in Germany and describes selected outcomes for prevalent patients with POAG.

PURPOSE

To estimate the prevalence and incidence of POAG in Germany, to describe the patient population in terms of comorbidity burden, routine care, and overall healthcare resource utilization (HCRU) and associated costs, and to describe treatment patterns over time in patients undergoing relevant laser procedures.

MATERIALS AND METHODS

Based on anonymized German claims data, we carried out a retrospective, noninterventional study covering calendar years 2016-2021.

RESULTS

For the adult German population (≥18 y), we estimated a POAG 1-year prevalence of 1.70% and a 1-year incidence of 0.17% in 2018; both increased with age, peaking in 80- to 89-year-olds. Prevalence and incidence were lower in 2020 (1.65% and 0.16%, respectively), the first year of the SARS-CoV-2 pandemic. Most patients solely received topical treatment. Most surgically treated patients underwent laser trabeculoplasty, followed by laser iridotomy, trabeculectomy, and filtration operations with implant. In patients undergoing laser trabeculoplasty, the treatment regimen was nearly unchanged in the second year after, compared with 2 years before the procedure. Multimorbidity was commonly observed; 75.5% of patients had arterial hypertension and 50.0% had disorders of lipoprotein metabolism and other lipidemias, compared with 60.1% and 39.2%, respectively, in an age- and sex-matched control sample.

CONCLUSIONS

Our study provides insights into epidemiology and routine care of POAG in Germany and HCRU in prevalent patients. There was little change in treatment regimens in patients who underwent laser trabeculoplasty, 2 years after the procedure. Most patients were multimorbid highlighting the need for comprehensive care.

Relationship between Intraocular Pressure Fluctuation and Visual Field Progression Rates in the United Kingdom Glaucoma Treatment Study

PURPOSE

To investigate whether intraocular pressure (IOP) fluctuation is associated independently with the rate of visual field (VF) progression in the United Kingdom Glaucoma Treatment Study.

DESIGN

Randomized, double-masked, placebo-controlled multicenter trial.

PARTICIPANTS

Participants with ≥5 VFs (213 placebo, 217 treatment).

METHODS

Associations between IOP metrics and VF progression rates (mean deviation [MD] and five fastest locations) were assessed with linear mixed models. Fluctuation variables were mean Pascal ocular pulse amplitude (OPA), standard deviation (SD) of diurnal Goldmann IOP (diurnal fluctuation), and SD of Goldmann IOP at all visits (long-term fluctuation). Fluctuation values were normalized for mean IOP to make them independent from the mean IOP. Correlated nonfluctuation IOP metrics (baseline, peak, mean, supine, and peak phasing IOP) were combined with principal component analysis, and principal component 1 (PC1) was included as a covariate. Interactions between covariates and time from baseline modeled the effect of the variables on VF rates. Analyses were conducted separately in the two treatment arms.

MAIN OUTCOME MEASURES

Associations between IOP fluctuation metrics and rates of MD and the five fastest test locations.

RESULTS

In the placebo arm, only PC1 was associated significantly with the MD rate (estimate, -0.19 dB/year [standard error (SE), 0.04 dB/year]; P < 0.001), whereas normalized IOP fluctuation metrics were not. No variable was associated significantly with MD rates in the treatment arm. For the fastest five locations in the placebo group, PC1 (estimate, -0.58 dB/year [SE, 0.16 dB/year]; P < 0.001), central corneal thickness (estimate, 0.26 dB/year [SE, 0.10 dB/year] for 10 μm thicker; P = 0.01) and normalized OPA (estimate, -3.50 dB/year [SE, 1.04 dB/year]; P = 0.001) were associated with rates of progression; normalized diurnal and long-term IOP fluctuations were not. In the treatment group, only PC1 (estimate, -0.27 dB/year [SE, 0.12 dB/year]; P = 0.028) was associated with the rates of progression.

CONCLUSIONS

No evidence supports that either diurnal or long-term IOP fluctuation, as measured in clinical practice, are independent factors for glaucoma progression; other aspects of IOP, including mean IOP and peak IOP, may be more informative. Ocular pulse amplitude may be an independent factor for faster glaucoma progression.

FINANCIAL DISCLOSURE(S)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Independent Effects of Blood Pressure on Intraocular Pressure and Retinal Ganglion Cell Degeneration: A Mendelian Randomization Study

Purpose

To investigate the causal effect of elevated blood pressure on primary open-angle glaucoma (POAG) and POAG endophenotypes.

Methods

Two-sample Mendelian randomization (MR) was performed to investigate the causal effect of elevated systolic blood pressure (SBP) (N = 757,601) and diastolic blood pressure (DBP) (N = 757,601) on intraocular pressure (IOP) (N = 139,555), macular retinal nerve fiber layer (mRNFL) thickness (N = 33,129), ganglion cell complex (GCC) thickness (N = 33,129), vertical cup-to-disc ratio (VCDR) (N = 111,724), and POAG liability (Ncases = 16,677, Ncontrols = 199,580). The primary analysis was conducted using the inverse-variance weighted approach. Sensitivity analyses were performed to investigate robustness to horizontal pleiotropy, winner's curse, and collider bias. Multivariable MR was performed to investigate whether any effect of blood pressure on retinal ganglion cell degeneration was mediated through increased IOP.

Results

Increased genetically predicted SBP and DBP associated with an increase in IOP (0.17 mm Hg [95% CI = 0.11 to 0.24] per 10 mm Hg higher SBP, P = 5.18 × 10-7, and 0.17 mm Hg [95% CI = 0.05 to 0.28 mm Hg] per 10 mm Hg higher DBP, P = 0.004). Increased genetically predicted SBP associated with a thinner GCC (0.04 µm [95% CI = -0.07 to -0.01 µm], P = 0.018) and a thinner mRNFL (0.04 µm [95% CI = -0.07 to -0.01 µm], P = 0.004), an effect that arises independently of IOP according to our mediation analysis. Neither SBP nor DBP associated with VCDR or POAG liability.

Conclusions

These findings support a causal effect of elevated blood pressure on retinal ganglion cell degeneration that does not require intermediary changes in IOP. Targeted blood pressure control may help preserve vision by lowering IOP and, independently, by preventing retinal ganglion cell degeneration, including in individuals with a normal IOP.

Comparative features of superior versus inferior hemisphere microvasculature dropout in open-angle glaucoma

PURPOSE

This study aimed to investigate differences in microvasculature dropout (MvD) between the superior and inferior hemispheres in glaucoma patients.

STUDY DESIGN

Retrospective and cross-sectional.

METHODS

Fifty-eight eyes of 58 open-angle glaucoma patients (age 61.12 ± 10.19 years, mean deviation - 7.32 ± 6.36 dB) were included. MvD was detected with en face images from swept-source optical coherence tomography angiography. Blood flow at the optic nerve head was measured with laser speckle flowgraphy, represented as the mean blur rate in tissue (MBRT). Logistic and linear regression models adjusted for age, intraocular pressure, axial length, and circumpapillary retinal nerve fiber layer thickness were used to investigate the relationship between various factors and MvD angle in each hemisphere.

RESULTS

The presence of inferior MvD was related to peripapillary atrophy-β area (odds ratio = 14.10 [2.49-234.00], P = 0.019). Superior MvD angle was significantly related to MBRT in the superior quadrant (β = -0.31 [- 0.60 - -0.02], P = 0.037). Inferior MvD angle was significantly related to peripapillary atrophy-β area (β = 0.49 [0.21-0.77], P = 0.001).

CONCLUSIONS

Only superior MvD demonstrated a significant relationship with reduced ocular blood flow. In contrast, inferior MvD was associated with mechanical stress. These findings may suggest a potential difference in pathophysiology between superior and inferior MvD.

Comparing Intraocular Pressure, Ocular Blood Flow, and Retinal Nerve Fiber Layer Thickness in Early and Chronic Hypertensives With Normotensives

PURPOSE

To compare blood pressure (BP), intraocular pressure (IOP), ophthalmic artery flow (OAF) velocity, retinal nerve fiber layer (RNFL) thickness, and visual fields in newly diagnosed hypertension (HT) patients (before treatment), chronic HT (on antihypertensive medications >5 years) and normotensives.

METHODS

A prospective, cross-sectional study at a tertiary care centre in India. Three groups of 45 patients each: group 1 - early HT, group 2 - chronic HT, and Group 3 - normotensives, underwent evaluation of BP, IOP by Goldmann applanation tonometry (GAT), OAF velocity by transcranial doppler (TCD), RNFL analysis by spectral-domain optical coherence tomography (SD-OCT), and visual fields.

RESULTS

The BP was highest in early HT > chronic HT > normotensives (p < 0.001). The IOP of early HT, chronic HT, and normotensives were 15.87 ± 2.19 mmHg, 13.47 ± 1.92 mmHg, and 15.67 ± SD 1.75 mmHg (p < 0.001). The OAF velocity [peak systolic velocity (PSV), end-diastolic velocity (EDV) in cm/sec] was lowest in chronic HT (30.80 ± 7.05, 8.58 ± 1.58) < early HT (35.47 ± 5.34, 10.02 ± 1.74) < normotensives (36.29 ± 4.43, 10.44 ± 2.29), (p < 0.001). The average RNFL thickness was significantly lower in chronic HT (p = 0.022). The PSV, EDV, and MFV showed significant correlation with IOP (r = 0.247, p = 0.004; r = 0.206, p = 0.016; r = 0.266, p = 0.002) and average RNFL thickness (r = 0.309, p= <0.001; r = 0.277, p = 0.001; r = 0.341, p < 0.001).

CONCLUSIONS

Patients with chronic HT demonstrated the lowest retrobulbar flows, IOP and lower RNFL measurements. Lower ocular perfusion may be associated with lower IOP and may be a risk factor for end-organ damage (RNFL) independent of IOP.

Polygenic risk score-based phenome-wide association for glaucoma and its impact on disease susceptibility in two large biobanks

BACKGROUND

Glaucoma is a leading cause of worldwide irreversible blindness. Considerable uncertainty remains regarding the association between a variety of phenotypes and the genetic risk of glaucoma, as well as the impact they exert on the glaucoma development.

METHODS

We investigated the associations of genetic liability for primary open angle glaucoma (POAG) with a wide range of potential risk factors and to assess its impact on the risk of incident glaucoma. The phenome-wide association study (PheWAS) approach was applied to determine the association of POAG polygenic risk score (PRS) with a wide range of phenotypes in 377, 852 participants from the UK Biobank study and 43,623 participants from the Penn Medicine Biobank study, all of European ancestry. Participants were stratified into four risk tiers: low, intermediate, high, and very high-risk. Cox proportional hazard models assessed the relationship of POAG PRS and ocular factors with new glaucoma events.

RESULTS

In both discovery and replication set in the PheWAS, a higher genetic predisposition to POAG was specifically correlated with ocular disease phenotypes. The POAG PRS exhibited correlations with low corneal hysteresis, refractive error, and ocular hypertension, demonstrating a strong association with the onset of glaucoma. Individuals carrying a high genetic burden exhibited a 9.20-fold, 11.88-fold, and 28.85-fold increase in glaucoma incidence when associated with low corneal hysteresis, high myopia, and elevated intraocular pressure, respectively.

CONCLUSION

Genetic susceptibility to POAG primarily influences ocular conditions, with limited systemic associations. Notably, the baseline polygenic risk for POAG robustly associates with new glaucoma events, revealing a large combined effect of genetic and ocular risk factors on glaucoma incidents.

[Glaucoma Patient with Suspected Flammer Syndrome: Diagnostic Procedures and Therapeutic Implications]

If glaucoma damage develops despite normal intraocular pressure or if the damage progresses despite well-controlled intraocular pressure, we usually find other risk factors. One important group are the vascular factors. We should focus not only on the classical risk factors of atherosclerosis, such as arterial hypertension or dyslipidaemia, but also on dysregulation of blood flow, especially on primary vascular dysregulation (PVD). Low blood pressure, either current or in adolescence, low body mass index or frequently cold hands and feet may provide important hints. Very often PVD is coupled with a number of other symptoms and signs, and we then speak of a Flammer Syndrome (FS). If there is any indication of FS, we take a targeted patient history, undertake 24 h blood pressure monitoring, measure retinal venous pressure, and perform a dynamic retinal vessel analysis or nail fold capillary microscopy. This is especially recommended if the patient is relatively young or the damage is progressing rapidly. If the suspicion is confirmed, we then try to reduce the drops in blood pressure, lower the retinal venous pressure, improve the regulation of blood flow and reduce the oxidative stress in the mitochondria.

Comparison of Ocular Blood Flow in Glaucomatous Eyes and Nonglaucomatous Eyes at a Tertiary Hospital in South India: A Prospective Case-control Study

Aim

To compare the ocular blood flow in glaucomatous eyes and normal healthy eyes. This study compares open-angle glaucoma patients to healthy adults by measuring various parameters in the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary artery (SPCA).

Materials and methods

A total of 50 glaucomatous eyes and 50 normal eyes were included in a prospective case-control study over 1 year. The color Doppler imaging (CDI) was conducted using a noninvasive linear multifrequency probe with a frequency range of 5-9 MHz. OA, CRA, and SPCA were measured for peak systolic velocity (PSV), end-diastolic volume (EDV), pulsatility index (PI), and resistivity index (RI).

Results

When compared with controls, PSV was decreased in all three vessels, with the results being remarkable only in CRA. The EDV also showed a remarkable decrease in all three vessels. Additionally, all three vessels showed significant increases in PI and RI except OA, p-value < 0.05.

Conclusion

Blood velocity is decreased, and resistive indices are increased in glaucomatous eyes compared with normal eyes. Variations in ocular blood flow could be a cause or consequence of glaucomatous optic neuropathy and are an important predictor of disease progression.

How to cite this article

Murugesan MAD, Venkat P, Basetti B. Comparison of Ocular Blood Flow in Glaucomatous Eyes and Nonglaucomatous Eyes at a Tertiary Hospital in South India: A Prospective Case-control Study. J Curr Glaucoma Pract 2024;18(2):45-50.

Neuroprotective Effects of Anti-diabetic Drugs in the Treatment of Patients with Diabetes and Glaucoma or at High Risk for Glaucoma

There is an association between glaucoma and several risk factors and metabolic diseases, such as type 2 diabetes mellitus. Diabetes mellitus leads to neurodegenerative changes, both peripherally and in the brain. This might be a shared pathophysiology and etiology for both glaucoma and diabetes. It is interesting that drugs for the treatment of diabetes seem to have neuroprotective properties independent of their blood sugar reduction. Although prospective, randomized, clinical studies are still missing, particularly metformin and glucagon-like peptide receptor agonists (GLP 1 RA) seem to have neuroprotective effects. Sulphonylureas (e.g., glibenclamide, glimepiride) are still used. They frequently potently reduce blood pressure but may be less neuroprotective. In the present review, the evidence for neuroprotective effects of the different antidiabetic drugs is presented and a possible differential therapy for patients with diabetes and glaucoma, or at high risk of glaucoma, will be discussed.

The prevalence of glaucoma in a 70-year-old Swedish population in the city area of Gothenburg

PURPOSE

To determine the prevalence of and risk factors for open-angle glaucoma in a population of 70-year-olds in Gothenburg, Sweden and to compare the visual function between the glaucoma population and the non-glaucoma population.

METHODS

Of the entire cohort (n = 1203), 1182 participants responded a questionnaire on self-reported glaucoma and were tested for blood pressure (BP) and diabetes. In all, 560 participants underwent ophthalmic examination including best-corrected visual acuity (BCVA), intraocular pressure (IOP), central corneal thickness (CCT), contrast sensitivity (CS), perimetry and photos of the retina and lens.

RESULTS

Glaucoma prevalence was 4.8% (95% confidence interval, 3.0%-6.6%), of which 56% was previously undiagnosed. The proportion of participants with diastolic BP >90 mmHg was higher in the non-glaucomatous group (8.3%) than the glaucoma group (0%), p < 0.001. A family history of glaucoma was present in a larger proportion of the glaucoma group (39%) than of the non-glaucomatous group (1.1%), p = 0.001. Mean IOP in individuals without glaucoma was 16 mmHg, versus 21 mmHg in participants with glaucoma detected at the examination. IOP was ≤21 mmHg in 67% among participants with previously unknown glaucoma. BCVA was lower in eyes with previously unknown glaucoma than in eyes without glaucoma (p = 0.017) but BCVA in the best eye did not differ. CCT and CS were similar in all cases.

CONCLUSIONS

The prevalence of glaucoma was comparable to that reported previously. A family history of glaucoma and higher IOP were risk factors associated with glaucoma. BCVA in the best eye did not differ significantly between subjects with and without glaucoma.

The association between intraocular pressure dynamics during dark-room prone testing and intraocular pressure over a relatively long-term follow-up period in primary open-glaucoma patients

PURPOSE

To investigate the relationship between the dynamics of intraocular pressure (IOP) during dark-room prone testing (DRPT) and IOP over a relatively long-term follow-up period.

METHODS

This retrospective study enrolled 84 eyes of 51 primary open-angle glaucoma patients who underwent DRPT for whom at least three IOP measurements made using Goldmann applanation tonometry were available over a maximum follow-up period of two years. We excluded eyes with a history of intraocular surgery or laser treatment and those with changes in topical anti-glaucoma medication during the follow-up period. In DRPT, IOP was measured in the sitting position, and after 60 min in the prone position in a dark room, IOP was measured again. In this study, IOP fluctuation refers to the standard deviation (SD) of IOP, and IOP max indicates the maximum value of IOP during the follow-up. The relationship between these parameters was analyzed with a linear mixed-effects model, adjusting for clinical parameters including age, gender, and axial length.

RESULTS

IOP increased after DRPT with a mean of 6.13 ± 3.55 mmHg. IOP max was significantly associated with IOP after DRPT (β = 0.38; p < 0.001). IOP fluctuation was significantly associated with IOP change in DRPT (β = 0.29; p = 0.007).

CONCLUSION

Our findings suggest that short-term and relatively long-term IOP dynamics are associated. Long-term IOP dynamics can be predicted by DRPT to some extent.

From the past to the present, optical coherence tomography in glaucoma: a practical guide to a common disease

Glaucoma comprises a group of disorders of the optic nerve that cause degenerative optic neuropathy, characterised by failure of neuroretinal rim tissue in the optic nerve head, retinal nerve fibre layer, and retinal ganglion cells. Glaucoma imposes a serious epidemiological threat, with an steady increase in the global number of cases. In the current ophthalmological practice, glaucoma is diagnosed via a series of examinations, including routine funduscopic examination, ocular tonometry, gonioscopy, measurement of the visual field, and assessment using the optical coherence tomography (OCT) technique. Nowadays, the OCT technique helps in systematising the diagnostic pathway and is a basic diagnostic tool for detection of early glaucomatous eye changes. It is also vital in assessing progression and monitoring treatment results of patients. The aim of this review was to present the OCT technique as a main tool in diagnosing and monitoring glaucoma.

Glaucoma: from pathogenic mechanisms to retinal glial cell response to damage

Glaucoma is a neurodegenerative disease of the retina characterized by the irreversible loss of retinal ganglion cells (RGCs) leading to visual loss. Degeneration of RGCs and loss of their axons, as well as damage and remodeling of the lamina cribrosa are the main events in the pathogenesis of glaucoma. Different molecular pathways are involved in RGC death, which are triggered and exacerbated as a consequence of a number of risk factors such as elevated intraocular pressure (IOP), age, ocular biomechanics, or low ocular perfusion pressure. Increased IOP is one of the most important risk factors associated with this pathology and the only one for which treatment is currently available, nevertheless, on many cases the progression of the disease continues, despite IOP control. Thus, the IOP elevation is not the only trigger of glaucomatous damage, showing the evidence that other factors can induce RGCs death in this pathology, would be involved in the advance of glaucomatous neurodegeneration. The underlying mechanisms driving the neurodegenerative process in glaucoma include ischemia/hypoxia, mitochondrial dysfunction, oxidative stress and neuroinflammation. In glaucoma, like as other neurodegenerative disorders, the immune system is involved and immunoregulation is conducted mainly by glial cells, microglia, astrocytes, and Müller cells. The increase in IOP produces the activation of glial cells in the retinal tissue. Chronic activation of glial cells in glaucoma may provoke a proinflammatory state at the retinal level inducing blood retinal barrier disruption and RGCs death. The modulation of the immune response in glaucoma as well as the activation of glial cells constitute an interesting new approach in the treatment of glaucoma.

Change of Intraocular Pressure Over 5 Years and its Relationship to Cardiovascular Parameters: Results From the Gutenberg Health Study

Purpose

To investigate the longitudinal change in intraocular pressure (IOP) over 5 years and its relationship with cardiovascular parameters in a population-based sample in Germany.

Methods

The Gutenberg Health Study is a prospective, observational, single-center cohort study. The sample was equally stratified for sex, residence, and age decade. IOP was measured with noncontact tonometry at baseline and at 5-year follow-up. Cardiovascular parameters, including body mass index (BMI), systolic blood pressure, and diabetes status, were assessed. Participants without IOP measurement at one time point, who were taking IOP-lowering medications, or who had ophthalmic surgery during the 5-year follow-up interval were excluded, as well as those with glaucoma diagnosis. Univariable and multivariable linear regression analyses were conducted.

Results

This analysis included 9633 participants (48.9% female). The mean IOP increased from 14.04 ± 2.78 mmHg at baseline to 14.77 ± 2.92 mmHg at 5-year follow-up (P < 0.001). In multivariable linear regression analyses, an increase in BMI was associated with an increase in IOP over time (P < 0.001), whereas a higher baseline BMI was associated with a lower IOP change (P < 0.001). Higher age and male sex were associated with higher IOP change (P < 0.001). A change in systolic blood pressure was associated with IOP change, whereas baseline systolic blood pressure and diabetes status were not associated.

Conclusions

This population-based study found a relationship between IOP change over 5 years and BMI and systolic blood pressure change, respectively. These findings suggest the importance of monitoring cardiovascular risk factors in IOP management.

Relationship Between Intraocular Pressure and Age: A Population-Based Study in Nepal

PRCIS

Intraocular pressure (IOP) decreased with age in a population-based study in Nepal, from a mean of 14.1 mm Hg among those 60-64 years old to 13.0 mm Hg among those 80 years old or older.

PURPOSE

Few studies have assessed the distribution of IOP from the Indian subcontinent, despite its large population and high burden of glaucoma. The objective of this study was to assess the distribution of IOP measurements from adults living in a lowland region of Nepal.

METHODS

In a population-based cross-sectional study, all individuals aged 60 years and older from an area of lowland Nepal were invited for an IOP assessment with a rebound tonometer.

RESULTS

Of 160 communities (28,672 people aged ≥60 y) enrolled, 79 (13,808 people aged ≥60 y) were randomly selected for IOP testing. Of those eligible, 10,017 (72.5%) individuals underwent tonometry. Mean IOP decreased monotonically over 5-year age groups, from 14.1 mm Hg (SD: 3.6) among those aged 60-64 years to 13.0 mm Hg (SD: 4.2) among those 80 years or older. The 97.5th percentile IOP measurement was 21.0 mm Hg for all age groups. In adjusted analyses, younger age, self-reported diabetes, and higher population density were each associated with higher IOP, and self-reported cataract surgery was associated with lower IOP.

CONCLUSIONS

Mean IOP was lower among older individuals in Nepal, consistent with many studies from East Asia and in contrast to many studies from western populations. These results suggest that ethnic background might be a consideration when diagnosing ocular hypertension.

Association between lifestyle habits and glaucoma incidence: a retrospective cohort study

BACKGROUND/OBJECTIVES

Although lifestyle habits may represent modifiable risk factors of glaucoma, the association between lifestyle factors and glaucoma is not well understood. The aim of this study was to investigate the association between lifestyle habits and the development of glaucoma.

SUBJECTS/METHODS

Participants who underwent health check-ups from 2005 to 2020 using a large-scale administrative claims database in Japan were included in the study. Cox regression analyses were performed where glaucoma development was regressed on the lifestyle (body mass index, current smoking, frequency and amount of alcohol consumption, eating habits, exercise habits and quality of sleep), age, sex, hypertension, diabetes mellitus and dyslipidaemia.

RESULTS

Among the 3,110,743 eligible individuals, 39,975 developed glaucoma during the mean follow-up of 2058 days. Factors associated with increased risk of glaucoma were overweight/obese (vs. moderate weight: hazard ratio, 1.04 [95% confidence interval, 1.02-1.07]), alcohol consumption of 2.5-4.9 units/day, 5-7.4 units/day, and ≥7.5 units/day (vs. <2.5 units/day: 1.05 [1.02-1.08], 1.05 [1.01-1.08] and 1.06 [1.01-1.12], respectively), skipping breakfast (1.14 [1.10-1.17]), late dinner (1.05 [1.03-1.08]) and daily walking of 1 h (1.14 [1.11-1.16]). Factors associated with decreased risk of glaucoma were daily alcohol consumption (vs. rarely: 0.94 [0.91-0.97]) and regular exercise (0.92 [0.90-0.95]).

CONCLUSIONS

Moderate body mass index, having breakfast, avoiding late dinner, limiting alcohol intake to <2.5 units/day, and regular exercise were associated with a reduced risk of developing glaucoma in the Japanese population. These findings may be useful for promoting glaucoma prophylaxis.

Association between dietary calcium, potassium, and magnesium consumption and glaucoma

BACKGROUND

Calcium (Ca), potassium (K) and magnesium (Mg) may be involved in the occurrence and development of glaucoma by influencing the retinal oxidative stress and regulate blood pressure. However, epidemiological opinions on dietary intake of macroelement related to glaucoma are inconsistent. Herein, this study aims to explore the association between dietary Ca, K, and Mg consumption and glaucoma.

METHODS

Data of 7,042 adults aged ≥40 years old who received the glaucoma examinations were extracted from the National Health and Nutrition Examination Survey (NHANES) database from 2005 to 2008 in this cross-sectional study. Univariate and multivariate logistic regression were used to explore the association between dietary Ca, K, and Mg intake and glaucoma with the odd ratios (ORs) and 95% confidence intervals (CIs). We also investigated this relationship in individuals of different age, with/without hypertension and visual field defect (VFD).

RESULTS

There were 502 (8.11%) participants had glaucoma. After adjusted for covariables, we found that enough dietary Ca consumption was related to a decreased risk of glaucoma [OR = 0.59, 95%CI: (0.42-0.81)], whether in persons with/without hypertension (all P<0.05). In particular, dietary K intake may be a potential protect factor for glaucoma in non-hypertension populations [OR = 0.47, 95%CI: (0.22-0.99), P = 0.049]. Additionally, hypertension/non-hypertension persons who aged <65 years old or with/without VFD should all pay attention to the enough dietary supplement of Ca, K, and Mg according to their own circumstances.

CONCLUSION

Enough dietary Ca, K, and Mg consumption may be potential protect factors of glaucoma that could provide some dietary reference for developing targeted glaucoma prevention and control measures.

Modeling tissue co-regulation estimates tissue-specific contributions to disease

Integrative analyses of genome-wide association studies and gene expression data have implicated many disease-critical tissues. However, co-regulation of genetic effects on gene expression across tissues impedes distinguishing biologically causal tissues from tagging tissues. In the present study, we introduce tissue co-regulation score regression (TCSC), which disentangles causal tissues from tagging tissues by regressing gene-disease association statistics (from transcriptome-wide association studies) on tissue co-regulation scores, reflecting correlations of predicted gene expression across genes and tissues. We applied TCSC to 78 diseases/traits (average n = 302,000) and gene expression prediction models for 48 GTEx tissues. TCSC identified 21 causal tissue-trait pairs at a 5% false discovery rate (FDR), including well-established findings, biologically plausible new findings (for example, aorta artery and glaucoma) and increased specificity of known tissue-trait associations (for example, subcutaneous adipose, but not visceral adipose, and high-density lipoprotein). TCSC also identified 17 causal tissue-trait covariance pairs at 5% FDR. In conclusion, TCSC is a precise method for distinguishing causal tissues from tagging tissues.

Familial normal tension glaucoma genetics

Glaucoma is defined by characteristic optic nerve damage and corresponding visual field defects and is the leading cause of irreversible blindness in the world. Elevated intraocular pressure (IOP) is a strong risk factor for developing glaucoma. However, glaucoma can occur at any IOP. Normal tension glaucoma (NTG) arises with IOPs that are within what has been defined as a normal range, i.e., 21 mm Hg or less, which may present challenges in its diagnosis and management. Identifying inheritance patterns and genetic mutations in families with NTG has helped elucidate mechanisms of NTG, however the pathophysiology is complex and not fully understood. Approximately 2% of NTG cases are caused primarily by mutations in single genes, optineurin (OPTN), TANK binding kinase 1 (TKB1), or myocilin (MYOC). Herein, we review pedigree studies of NTG and autosomal dominant NTG caused by OPTN, TBK1, and MYOC mutations. We review identified mutations and resulting clinical features of OPTN-associated and TBK1-associated NTG, including long-term follow up of these patients with NTG. In addition, we report a new four-generation pedigree of NTG caused by a Glu50Lys OPTN mutation, including six family members with a mean follow up of 17 years. Common features of OPTN -associated NTG due to Glu50Lys mutation included early onset of disease with an IOP <21 mm Hg, marked optic disc cupping, and progressive visual field loss which appeared to stabilize once an IOP of less than 10 mm Hg was achieved. Lastly, we review risk factor genes which have been identified to contribute to the complex inheritance of NTG.

The Association between Vascular Abnormalities and Glaucoma-What Comes First?

Glaucoma is a leading cause of irreversible blindness worldwide. While intraocular pressure (IOP) presents a major risk factor, the underlying pathophysiology still remains largely unclear. The correlation between vascular abnormalities and glaucoma has been deliberated for decades. Evidence for a role played by vascular factors in the pathogenesis of glaucomatous neurodegeneration has already been postulated. In addition, the fact that glaucoma causes both structural and functional changes to retinal blood vessels has been described. This review aims to investigate the published evidence concerning the relationship between vascular abnormalities and glaucoma, and to provide an overview of the "chicken or egg" dilemma in glaucoma. In this study, several biomarkers of glaucoma progression from a vascular perspective, including endothelin-1 (ET-1), nitric oxide, vascular endothelial growth factor (VEGF), and matrix metalloproteinases (MMPs), were identified and subsequently assessed for their potential as pharmacological intervention targets.

Increased Risks of Open-Angle Glaucoma in Untreated Hypertension

PURPOSE

Hypertension (HTN) has been associated with open-angle glaucoma (OAG), but whether elevated blood pressure (BP) alone is associated with OAG is unknown. Whether stage 1 hypertension, as per the 2017 American College of Cardiology/American Heart Association (ACC/AHA) BP guidelines, increases the risk of the disease is uncertain.

DESIGN

Retrospective, observational, cohort study.

METHODS

A total of 360,330 subjects who were ≥40 years of age and not taking antihypertensive or antiglaucoma drugs at the time of health examinations between January 1, 2002, and December 31, 2003, were included. Subjects were categorized based on their untreated BP, into normal BP (systolic BP [SBP] <120 and diastolic BP [DBP] <80 mm Hg; n = 104,304), elevated BP (SBP 120-129 and DBP <80 mm Hg; n = 33,139), stage 1 HTN (SBP 130-139 or DBP 80-89 mm Hg; n = 122,534), or stage 2 HTN (SBP ≥140 or DBP ≥90mm Hg; n = 100,353). Cox regression analysis was performed to calculate hazard ratios (HR) of OAG risk.

RESULTS

The mean age of the subjects was 51.17 ± 8.97 years, and 56.2% were male. During a mean follow-up period of 11.76 ± 1.37 years, 12,841 subjects (3.56%) were diagnosed with OAG. Multivariable-adjusted HRs (95% CIs) were 1.056 (0.985-1.132) for elevated BP, 1.101(1.050-1.155) for stage 1 HTN, and 1.114(1.060-1.170) for stage 2 HTN with normal BP as the reference.

CONCLUSIONS

The risk for OAG becomes greater with increases in untreated BP. Stage 1 HTN per the 2017 ACC/AHA BP guidelines is a significant risk factor for OAG.

Effect of alternate nostril breathing exercise on autonomic functions, ocular hypertension, and quality of life in elderly with systemic hypertension and high-tension primary open-angle glaucoma

Investigating the response of ocular hypertension and quality of life to a 4-week alternate-nostril breathing exercise (ANBE) in older adults with systemic hypertension (SH) and high-tension form of primary open-angle glaucoma (HTF-POAG) was our aim. Sixty older adults with SH and HTF-POAG were randomly assigned to the ANBE group (n=30, received morning and evening 30 min sessions of daily ANBE) or the control (waitlist) group (n=30). Right-eye intraocular pressure (IOP), left-eye IOP, blood pressure, short-form-36 survey (SF36S), rates of respiration and radial-artery pulsation, hospital anxiety and depression scale (depression subscale abbreviated as HADS-D and anxiety subscale abbreviated as HADS-A), and glaucoma quality-of-life 15-item questionnaire (GQoL-15) were assessed. All measurements were improved in the ANBE group only. In conclusion, a 4-week ANBE could be an adjunctive modality to improve HADS-D, rates of respiration and radial-artery pulsation, HADS-A, blood pressure, IOP, GQol-15, and SF36S in older adults SH and HTF-POAG.

Glaucoma and Systemic Disease

Glaucoma is the leading cause of irreversible blindness in the world. Due to its potential to cause permanent vision loss, it is important to understand how systemic conditions and their respective treatments can be associated with or increase the risk for developing glaucoma. In this review, we examined the literature for up-to-date discussions and provided commentary on glaucoma, its pathophysiology, and associated risk factors. We discuss systemic diseases and the impact, risk, and mechanism for developing glaucoma, including pharmacologically induced glaucoma; inflammatory and auto-immune conditions; infectious, dermatologic, cardiovascular, pulmonary, renal, urologic, neurologic, psychiatric and systemic malignancies: intraocular tumors; as well as pediatric, and genetic conditions. The goal of our discussion of systemic conditions including their commonality, mechanisms, treatments, and associations with developing glaucoma is to emphasize the importance of ocular examinations and follow-up with the multidisciplinary teams involved in the care of each patient to prevent unnecessary vision-loss.

Lateralized Raise in Intraocular Pressure During Electroconvulsive Therapy: A Tonometry Pilot Study

Right unilateral ECT causes an increase in eye pressure that is partially lateralized, higher on the right side.

Objective

The aim of this study was to evaluate intraocular pressure (IOP) changes during and after electroconvulsive therapy.

Methods

In 20 patients, IOP was measured using a handheld iCare tonometer before, during, and up to 15 minutes after the seizure. Electrode placement was either right unilateral (RUL) or bilateral (BL). Statistical analyses were done at baseline, during, and 15 minutes after the seizure.

Results

In the RUL group (n = 14), the IOP in the left eye increased from 14.8 mm Hg before the seizure to 27.8 mm Hg during the seizure (P = 0.0001) and decreased to 14.0 mm Hg after the seizure (P = 0.0002). The IOP in the right eye increased from 15.4 mm Hg before the seizure to 34.4 mm Hg during the seizure (P = 0.0001) and decreased to 16.0 mm Hg after the seizure (P = 0.0002).

In the BL group (n = 6), the IOP in the left eye increased from 13.0 mm Hg before the seizure to 26.3 mm Hg during the seizure (P = 0.1250) and decreased to 14.5 mm Hg after the seizure (P = 0.250). In the right eye, the IOP increased from 13.3 mm Hg before the seizure to 28.4 mm Hg during the seizure (P = 0.1250) and decreased to 13.7 mm Hg after the seizure (P = 0.25).

When the results were compared between the 2 electrode placements, the difference in IOP between the right and left eye was higher in the RUL group during (RUL 6.7 mm Hg vs BL 2.0 mm Hg, P = 0.0231) and after (RUL 2.1 mm Hg vs BL −0.8 mm Hg, P = 0.0492) the seizure.

Conclusions

RUL stimulation with electroconvulsive therapy causes a rise in IOP that is partially lateralized, ipsilateral to the side of stimulation.

Caveolin-1 in vascular health and glaucoma: A critical vascular regulator and potential therapeutic target

Caveolin-1 (Cav-1) is an integral scaffolding membrane protein found in most cell types. Cav-1 has been found to contribute significantly to ocular function, with mutations of Cav-1 being associated with a genetic risk of glaucoma development. Raised intraocular pressure (IOP) is a major modifiable risk factor for glaucoma. Cav-1 may be involved in both IOP-dependent and independent mechanisms involving vascular dysregulation. Systemic vascular diseases including hypertension, diabetes and hyperlipidaemia, have been shown to be associated with glaucoma development. Cav-1 is closely interlinked with endothelial nitric oxide synthase pathways that mediate vascular function and prevent cardiovascular diseases. Endothelial nitric oxide synthase and endothelin-1 are key vasoactive molecules expressed in retinal blood vessels that function to autoregulate ocular blood flow (OBF). Disruptions in the homeostasis of OBF have led to a growing concept of impaired neurovascular coupling in glaucoma. The imbalance between perfusion and neuronal stimulation arising from Cav-1 depletion may result in relative ischemia of the optic nerve head and glaucomatous injury. OBF is also governed by circadian variation in IOP and systemic blood pressure (BP). Cav-1 has been shown to influence central BP variability and other circadian rhythms such as the diurnal phagolysosomal digestion of photoreceptor fragments and toxic substrates to maintain ocular health. Overall, the vast implications of Cav-1 on various ocular mechanisms leading to glaucoma suggest a potential for new therapeutics to enhance Cav-1 expression, which has seen success in other neurodegenerative diseases.

Appraising the Effects of Metabolic Traits on the Risk of Glaucoma: A Mendelian Randomization Study

Metabolic traits are associated with the risk of developing glaucoma in observational studies. To assess whether theses associations reflect causality, we conducted a Mendelian randomization (MR) study. Our study included up to 20,906 glaucoma cases and 438,188 controls. Genetic instruments associated with the concerned 11 exposures at the genome-wide significance level were selected from corresponding genome-wide association studies. Summary-level data for glaucoma were obtained from the UK Biobank, the GERA study, and the FinnGen consortium. Univariable and multivariable MR analyses were conducted separately in two populations. Our results showed that higher genetic liability to type 2 diabetes (T2D) was causally and independently associated with an increased risk of glaucoma (odds ratio [OR], 1.11; 95% confidence interval [CI], 1.06-1.16; p = 4.4 × 10-6). The association for T2D persisted after multivariable adjustment. In addition, higher genetically predicted systolic blood pressure (SBP), fasting glucose (FG), and HbA1c, were also suggestively associated with glaucoma risk. The OR was 1.08 (95% CI, 1.01-1.16; p = 0.035) for SBP, 1.24 (95% CI, 1.05-1.47; p = 0.011) for FG, and 1.28 (95% CI, 1.01-1.61; p = 0.039) for HbA1c. No evidence was observed to support the causal effects of body mass index and blood lipids for glaucoma. This study suggests a causal role for diabetes, as well as possible roles for higher SBP, FG, and HbA1c in the development of glaucoma. Further validation is needed to assess the potential of these risk factors as pharmacological targets for glaucoma prevention.

Blood Pressure Measures and Incident Primary Open-Angle Glaucoma

Purpose

To investigate the association of systemic blood pressure and incident primary open-angle glaucoma (POAG) using a large open-access database.

Methods

Prospective cohort study included 484,268 participants from the UK Biobank without glaucoma at enrollment. Incident POAG events were recorded through assessment visits, hospital inpatient admissions, and primary care data. Blood pressure measures included systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP), and mean arterial pressure (MAP). Repeated measurements throughout the study period were analyzed as time-varying covariables. The parameters were modeled as both categorical and continuous nonlinear variables. The primary outcome measure was the relative hazard of incident POAG.

Results

There were 2390 incident POAG events over 5,715,480 person-years of follow-up. Median follow-up was 12.08 years. In multivariable analyses, compared to SBP and PP in the normal range (SBP, 120-130 mmHg; PP, 40-50 mmHg), higher SBP and PP were associated with an increased risk of incident POAG (linear trend P = 0.038 for SBP, P < 0.001 for PP). Specifically, SBP of 130 to 140 mmHg or 140 to 150 mmHg was associated with a 1.16 higher hazard of incident POAG (95% CI, 1.01-1.32 and 1.01-1.33, respectively), whereas a PP of greater than 70 mmHg was associated with a 1.13 higher hazard of incident glaucoma (95% CI, 1.00-1.29). In multivariable models, no statistically significant associations were found for DBP or MAP with incident glaucoma. These findings were similar when blood pressure measures were modeled as continuous variables.

Conclusions

Higher SBP and PP were associated with an increased risk of incident POAG. Further studies are required to characterize these relationships better.

Psychiatric diseases and dementia and their association with open-angle glaucoma in the total population of Stockholm

OBJECTIVE

Association between some somatic diseases and primary open-angle glaucoma (POAG) are well-known. We aimed to study psychiatric diseases and dementia and their association with POAG in the total population of Region Stockholm.

METHODS

All living individuals above 18 years of age who resided in Stockholm County, Sweden, on 1 January 2017 (N = 1,703,675) were included. Data were obtained from administrative regional data. We identified individuals with specified psychiatric disorders in the years 2010-2019, and further identified those with an incident diagnosis of POAG during 2012-2018. Analyses were performed by age-group and sex. We calculated odds ratios (ORs) with 95% confidence intervals (95% CI), adjusted for age and neighborhood socio-economic status for individuals with POAG, and used individuals without POAG as referents.

RESULTS

A total of 16,299 cases of POAG were identified, of whom 9204 were women and 7095 men. Adjusted OR (95% CI) for the risk of POAG was 0.653 (0.610-0.698) for women and 0.714 (0.656-0.778) for men with dementia, respectively. The OR for POAG was 0.478 (0.355-0.643) for women with psychosis, and 1.164 (1.105-1.227) for women with depression. A high neighbourhood socio-economic status was associated with a higher risk of POAG. Other associations were non-significant.

CONCLUSION

The prevalence of newly diagnosed POAG was decreased in men and women with dementia, and in women with psychosis, which could be an underestimation, owing to lack of investigation, which warrants attention. The risk of POAG was increased in women with depression, which could be secondary to the glaucoma diagnosis.KEY MESSAGESThe prevalence of newly diagnosed glaucoma was decreased in men and women with dementia, and in women with psychosis. A lower prevalence of newly diagnosed glaucoma may be due to an underestimation, owing to a lack of investigation.The risk of glaucoma was increased in women with depression, which could be secondary to the glaucoma diagnosis.

Fatty Liver Is an Independent Risk Factor for Elevated Intraocular Pressure

Elevated intraocular pressure (EIOP) is a major risk factor for glaucoma. Both EIOP and fatty liver share metabolic risk factors, which implies a possible link between EIOP and fatty liver. We aimed to determine the association of fatty liver with EIOP and estimate the effect of fatty liver on EIOP directly and indirectly through insulin resistance. Data from 16,240 adults who underwent health examinations at a single center were analyzed. Multiple logistic regression analyses revealed that fully adjusted odds ratio (OR) and 95% confidence interval (CI) for EIOP in the fatty liver group compared to the non-fatty liver group were 1.36 and 1.08-1.71. Alcoholic liver disease was associated with EIOP in subgroup analysis (OR = 1.80, 95% CI: 1.27-2.56). There was a linear dose-response relationship between EIOP and the severity of fatty liver. Mediation analysis revealed that the total effect of fatty liver on intraocular pressure was 0.90 (0.81-0.99), with a direct effect of 0.81 (0.71-0.90) and an indirect effect of 0.09 (0.06-0.11) through insulin resistance. Fatty liver is independently associated with EIOP. It primarily has a direct effect on intraocular pressure. This suggests that evaluation of EIOP should be considered in patients with fatty liver.

Relationship between blood pressure and intraocular pressure in the JPHC-NEXT eye study

Although a positive link between hypertension and intraocular pressure (IOP) has been suggested, the individual effects of systolic and diastolic blood pressure (SBP and DBP, respectively) on IOP remain unclear, particularly among Japanese populations. Here, we conducted a large-scale, cross-sectional study to determine individual and combined effects of SBP/DBP and hypertension on IOP. In total, 6783 Japanese people aged over 40 years underwent systemic and ophthalmological examinations, including measurements of blood pressure and IOP, conducted using non-contact tonometers. After adjusting for a priori known confounding factors, SBP and DBP levels were found to be positively correlated with IOP levels. The multivariable-adjusted odds ratio when comparing the hypertensive and normotensive groups for the prevalence of ocular hypertension was 1.88 (95% confidence interval, 1.14-3.08). When analysing the combined effects of SBP and DBP on ocular hypertension, SBP elevation had a greater effect on ocular hypertension than DBP increase. In conclusion, SBP and DBP levels and the prevalence of systemic hypertension were found to be positively associated with IOP levels and the prevalence of ocular hypertension in an ophthalmologically healthy Japanese population. Our findings suggest that systemic blood pressure control may be key for controlling IOP.

Repurposing Antihypertensive Drugs for the Prevention of Glaucoma: A Mendelian Randomization Study

Purpose

Several antihypertensive drugs have been used for the treatment of glaucoma. However, the effect of hypertension and antihypertensive drugs on glaucoma is still unclear.

Methods

Leveraging large-scale genome-wide association study summary statistics for glaucoma (Ncase = 4737, Ncontrol = 458,196), blood pressure (BP) (N = 422,771), and intraocular pressure (IOP) (N = 31,269), the genetic correlation and causal relationship of genetically assessed IOP, systolic blood pressure (SBP), diastolic blood pressure (DBP), and 12 types of antihypertensive drugs with glaucoma were evaluated using linkage disequilibrium score (LDSC) regression, univariate mendelian randomization (MR), and multivariable MR.

Results

LDSC results showed a suggestive association of glaucoma with SBP (Rg = 0.12, P = 0.0076) and DBP (Rg = 0.17, P = 0.02). In univariate MR, genetically elevated BP in participants was not identified to lead to an increased glaucoma risk (SBP: odds ratio [OR], 1.05 [95% confidence interval {CI}, 0.91-1.21]; P = 0.52; DBP: OR, 1.07 [95% CI, 0.93-1.23]; P = 0.34). The results of univariate MR were replicated in multivariable MR (SBP: OR, 0.95 [95% CI, 0.71-1.29]; P  = 0.75; DBP: OR, 1.13 [95% CI, 0.85-1.51]; P  = 0.41). Furthermore, there was insufficient evidence to suggest that antihypertensive drugs were associated with glaucoma.

Conclusions

Together, controlling BP may not help prevent and treat glaucoma, and antihypertensive drugs may neither treat nor worsen glaucoma.

Translational Relevance

Treating with antihypertensive drugs should not be used as an intervention for patients with glaucoma.

Association of Ambulatory Blood Pressure and Other Factors With Intraocular Pressure-Related 24-Hour Contact Lens Sensor Profile in Untreated Glaucoma

Purpose

To investigate the association of diurnal blood pressure (BP) and other factors with the intraocular pressure (IOP)–related 24-hour contact lens sensor (CLS) profile of patients with untreated glaucoma.

Methods

The prospective study included 82 patients with untreated normal-tension glaucoma. CLS measurements and ambulatory BP monitoring were performed simultaneously for 24 hours. The association between the mean arterial pressure (MAP) and CLS profile was examined for the daytime and nocturnal periods using linear regression analysis. The associations between other factors and the CLS profile were also examined.

Results

Multivariate analysis of data from 63 eligible patients showed that higher average MAPs were significantly associated with larger average nocturnal CLS values (β coefficient = 0.273; P = 0.023); a larger increase in the last CLS value (β coefficient = 0.366; P = 0.003); larger standard deviations (SDs) of CLS values for the daytime, nocturnal, and 24-hour periods (β coefficient = 0.407, 0.293, and 0.375; P < 0.001, P = 0.032 and 0.002, respectively); and higher average ocular pulse frequencies for the daytime, nocturnal, and 24-hour periods (β coefficient = 0.268, 0.380, and 0.403; P = 0.029, 0.002, and 0.001, respectively). Thicker subfoveal choroids and shorter axial length were significantly associated with larger SDs and larger average CLS values, respectively. Smaller anterior chamber volume and lower corneal hysteresis were associated with larger SDs or larger average ocular pulse amplitude.

Conclusions

Ambulatory BP and several ocular parameters were significantly associated with various parameters of the 24-hour CLS profile.

Translational Relevance

Ambulatory BP and ocular parameters may be modifiers of the 24-hour IOP-related profile of CLS.

The acute effect of systemic blood pressure reduction on intraocular pressure in hypertensive patients

OBJECTIVES:

Previous studies have shown an association between systemic hypertension and intraocular pressure (IOP). We analyzed the relationship between the decreases of the blood pressure (BP) and IOP in hypertensive patients.

METHODS:

The study includes a total of 214 patients: 158 hypertensive and 56 normotensive patients as study and control groups, respectively. The IOP of each eye in both the groups was measured once with a noncontact tonometer at presentation and an hour after BP reduction to normal in the study group. We analyzed the reduction in IOP with decreasing BP.

RESULTS:

In the study group, the mean IOP was 15.29 ± 4.05 mmHg in the right and 15.11 ± 3.78 mmHg in the left eyes. The mean IOP measured an hour after the patients became normotensive was 13.78 ± 4.06 mmHg in the right and 13.51 ± 3.82 in the left eyes. There was a statistically significant decrease in the IOPs (P < 0.001). The mean IOP in the control group was 13.54 ± 3.51 mmHg in the right and 13.20 ± 3.33 mmHg in the left eyes. The mean IOP at presentation in the study and control groups was found to be significantly different (P < 0.001).

CONCLUSIONS:

Patients in the study group showed a significantly higher IOP compared to patients in the normotensive group. Furthermore, patients in the study group showed a significant reduction in IOP after BP reduction. This may indicate that uncontrolled hypertension poses a risk for prolonged higher IOP. Prolonged higher IOP can be considered a risk factor for the glaucoma.

Bidirectional association between glaucoma and chronic kidney disease: A systematic review and meta-analysis

BACKGROUND

Glaucoma and chronic kidney disease (CKD) are prevalent and debilitating conditions, with common pathogenic pathways like oxidative stress and fluid dysregulation. We evaluated if there is a bidirectional association between them, as previous studies have yielded conflicting results.

METHODS

In this systematic review and meta-analysis, we searched PubMed, Embase and Cochrane Library from inception until 15 June 2021, including full-length English articles published in peer-reviewed journals reporting on glaucoma and CKD as either exposure or outcome, among participants aged ≥18 years. We pooled overall summary estimates of odds ratios using random-effect meta-analysis and conducted subgroup meta-analyses and univariate meta regression. We assessed risk of bias using the Newcastle-Ottawa Scale (NOS) and quality of evidence using the GRADE framework. Our article is PROSPERO-registered and adherent to both PRISMA and MOOSE guidelines. This review is registered with PROSPERO (CRD42021262846).

FINDINGS

We identified 14 articles comprising of 3 retrospective cohort studies and 12 cross-sectional studies from 2,428 records, including 1,978,254 participants. Risk of bias was low to moderate. Participants with CKD at baseline had higher pooled odds of glaucoma (odds ratio[OR]=1.18, 95% confidence interval[CI]=1.04-1.33, I2=66%, N=12) compared to participants without CKD. The association remained significant in subgroups of longitudinal studies, participants with diabetes, East Asian studies and primary open-angle glaucoma. In the reverse direction, participants with glaucoma at baseline had over three-fold higher odds of incident CKD compared to participants without glaucoma after 10-15 years of follow-up in longitudinal studies (OR=3.67, 95% CI=2.16-6.24, I2=75%, N=2). All studies adjusted for age and sex, while most studies adjusted for comorbidities such as diabetes and hypertension. Meta-regression identified ethnicity (East Asians vs Non-East Asians) as a significant effect moderator. Associations were robust to trim-and-fill adjustment for publication bias, single-study influence and cumulative meta-analyses.

INTERPRETATION

Our meta-analysis suggests a bidirectional relationship between glaucoma and CKD, particularly among East Asians. Further studies are required to elucidate underlying mechanisms and account for differential association by ethnicity.

FUNDING

Ching-Yu Cheng is supported by Clinician Scientist Award (NMRC/CSA-SI/0012/2017) of the Singapore Ministry of Health's National Medical Research Council.

High Blood Pressure and Intraocular Pressure: A Mendelian Randomization Study

Purpose

To test for causality with regard to the association between blood pressure (BP) and intraocular pressure (IOP) and glaucoma.

Methods

Single nucleotide polymorphisms (SNPs) associated with BP were identified in a genome-wide association study (GWAS) meta-analysis of 526,001 participants of European ancestry. These SNPs were used to assess the BP versus IOP relationship in a distinct sample (n = 70,832) whose corneal-compensated IOP (IOPcc) was measured. To evaluate the BP versus primary open-angle glaucoma (POAG) relationship, additional Mendelian randomization (MR) analyses were conducted using published GWAS summary statistics.

Results

Observational analysis revealed a linear relationship between BP traits and IOPcc, with a +0.28 mm Hg increase in IOPcc per 10-mm Hg increase in systolic BP (95% confidence interval [CI], 0.26-0.29); for diastolic blood pressure (DBP) and pulse pressure (PP), these estimates were +0.41 mm Hg and +0.36 mm Hg, respectively. An inverse-variance weighted MR analysis did not support a causal relationship, as the estimated causal effect was +0.01 mm Hg IOPcc per 10-mm Hg increase in systolic blood pressure (SBP); +0.13 mm Hg IOPcc per 10-mm Hg increase in DBP; and +0.02 mm Hg IOPcc per 10-mm Hg increase in PP (all P > 0.05). With regard to the risk of POAG, MR analyse yielded causal effect estimate of odds ratio = 0.98 (95% CI, 0.92-1.04) per 10-mm Hg increase in SBP. Neither DBP nor PP demonstrated evidence of a causal effect on POAG.

Conclusions

A range of different MR analysis methods provided evidence, in general, that the causal effect of BP on IOP (and POAG) was modest, or even zero. However, interpretation was complicated by SNPs associated with BP potentially having pleiotropic effects on IOP.

Predictors of Early Onset Glaucoma

Purpose/Relevance

To determine the influence of hypertension (HTN), type 2 diabetes (DM2), migraine, and obstructive sleep apnea (OSA) on the onset of primary open-angle glaucoma (POAG) to enhance predictive accuracy.

Methods

In this cross-sectional study, data for 389 eligible patients with POAG were collected through medical records review and phone surveys. All data were assessed collectively using stepwise multiple regression analysis to determine the relative contribution to age at POAG diagnosis. We used the following groups, based on age at diagnosis, HTN for patients with or without DM2 (model 1), HTN for patients with DM2 (model 2), DM2 for patients with or without HTN (model 3), and DM2 for patients with HTN (model 4).

Results

In model 1, age at HTN diagnosis was associated with age at POAG diagnosis (β = 0.14; 95% CI, 0.01–0.26, p = 0.04). In model 2, age at HTN diagnosis was not associated with age at POAG diagnosis (p > 0.05). In model 3, age at DM2 diagnosis was associated with age at POAG diagnosis (β = 0.37; 95% CI 0.16–0.58, p = 0.001). In model 4, age at DM2 diagnosis was associated with age at POAG diagnosis (β = 0.40; 95% CI 0.00–0.15, p = 0.003). Asian race/ethnicity was associated with early onset of POAG in model 3 (β = −6.44; 95% CI −12.34–0.54, p = 0.033). OSA and migraine did not influence the onset of POAG.

Conclusion

Our study found that the diagnosis of DM2 and HTN at an earlier age is associated with the early onset of POAG.