Effect of Mindfulness-Based Stress Reduction on Intraocular Pressure in Patients With Ocular Hypertension: A Randomized Control Trial

Relationship Between Glaucoma and Chronic Stress Quantified by Allostatic Load Score in the All of Us Research Program

PURPOSE

To assess the relationship between glaucoma and allostatic load (AL), an established framework for quantifying the physiologic effects of chronic stress through measurements of systemic biomarkers.

DESIGN

Retrospective case-control study.

METHODS

Participants of the National Institutes of Health All of Us (AoU) Research Program with complete AL biomarker data between December 1984 and June 2022 and with (cases) or without (controls) primary glaucoma were identified. AL scores were calculated using the adapted Seeman AL scale consisting of 10 systemic biomarkers: body mass index, systolic blood pressure, diastolic blood pressure, glycated hemoglobin, total cholesterol, triglycerides, glomerular filtration rate, albumin, C-reactive protein, and homocysteine. AL score was defined as the number of biomarkers with measurements in the highest risk quartiles. Age was calculated as the median age at the time of biomarker measurements. Logistic regression analysis was performed to assess the association between the earliest possible AL score and glaucoma adjusted for race or ethnicity. Mediation analysis was performed to estimate the relationship between race or ethnicity and glaucoma mediated by AL score.

RESULTS

The study cohort consisted of 349 cases (16.1%) and 1819 controls (83.9%) with 52.7% females, 2.2% Asians, 10.7% Blacks, 10.0% Hispanics, and 72.5% non-Hispanic Whites. At the earliest time point (median [interquartile range (IQR)] = 6.4 [1.9-12.2] years prior to diagnosis), cases had higher AL score than controls (3 [1-4] vs 2 [1-3], respectively; P < .001). On multivariable analysis, a higher AL score (OR=1.09 per point), Black race (OR=2.58), and Hispanic ethnicity (OR=2.12) conferred higher risk of glaucoma (P ≤ .02). The AL score partially mediated higher glaucoma risk among Blacks (7.5%) and Hispanics (5.0%) compared with non-Hispanic Whites. On subgroup analysis, higher AL score was significantly associated with primary open angle glaucoma (OR=1.11; P = .01) but not primary angle closure glaucoma (P = .87).

CONCLUSION

AoU participants with glaucoma had greater AL 6.4 years before diagnosis, and the AL score partially mediated racial or ethnic differences in glaucoma risk. These findings suggest chronic stress may increase risk for glaucoma and contribute to racial disparities in glaucoma burden.

Intraocular Pressure Response to Perceived Stress in Juvenile-Onset Open Angle Glaucoma

PRCIS

High perceived stress from academic pressure is associated with intraocular pressure (IOP) elevation and reduced fluctuation in juvenile-onset open angle glaucoma patients. Personalized stress assessment and relief strategies may serve as an adjunct therapy in glaucoma.

OBJECTIVE

To evaluate the effect of higher perceived stress, resulting from academic pressure, on IOP in juvenile-onset open angle glaucoma (JOAG) patients compared with healthy individuals.

METHODS

The study included 48 university students aged 18-27 years, comprising 24 JOAG patients on antiglaucoma eyedrops and 24 healthy controls. In an examiner-blind pretest-posttest design, participants' IOP was measured weekly using Goldmann tonometry during three follow-up visits at the beginning and end of the academic semester. Perceived Stress Scale (PSS) scores were also evaluated at these 2-time points to capture the contrast in perceived stress between periods of low and high academic pressure.

RESULTS

The baseline PSS score at the semester's start was lower in both groups (14.1±1.9 in glaucoma vs. 13.5±2.4 in control) and significantly increased by the end of the semester (29.2±2.1 vs. 28.5±1.3; P <0.001), indicating increased perceived stress. Concurrently, IOP rose from 22.01±5.87 to 25.08±5.84 mm Hg in the glaucoma group and from 11.36±2.03 to 13.65±2.11 mm Hg in the control group. Factorial analysis revealed a significant interaction between stress and JOAG ( F(1,94) =15.94, P =0.001), partial η 2 =0.08, with stress having a greater increase on IOP in the glaucoma group (+3.10 mm Hg) compared with the control group (+2.23 mm Hg) ( t(94) =4.457, P <0.001).

CONCLUSIONS

Higher perceived stress significantly increases IOP, especially in JOAG patients, suggesting personalized stress management as a potential adjunct therapy for patients.

Evaluation of Visual Cortex Activity Using Functional Near-Infrared Spectroscopy in Primary Open Angle and Primary Angle Closure Glaucoma: A Pilot Study

PRCIS

Functional near-infrared spectroscopy (fNIRS) was used to assess visual cortical activity in patients with primary open angle (POAG) and primary angle closure (PACG) glaucomas. There was decreased activity in the visual cortex of glaucoma patients correlating with the severity of glaucoma.

OBJECTIVE

To evaluate visual cortex activity using fNIRS in POAG and PACG compared with healthy controls.

METHODS

A total of 30 POAGs, 31 PACGs, and 30 healthy aged-matched controls from a single centre were recruited in this cross-sectional observational pilot study with purposive sampling. The POAG and PACG groups were age-matched but were not matched for disease severity at recruitment. All participants underwent fNIRS testing using a multichannel continuous-wave near-infrared system NIRSport 8×7 device (NIRx Medizintechnik GmbH). The visual cortex activity was evaluated in terms of the maximum amplitude of change in oxyhemoglobin (OxyHb) concentration over 10 seconds, and a comparison was done among 3 groups. Both POAG and PACG groups were combined (termed as glaucoma group) to assess the relationship of visual cortical activity with disease severity (by visual field defect (mean deviation) and retinal nerve fibre layer thickness).

RESULTS

All participants showed the characteristic response of increased OxyHb and decreased deoxyhemoglobin during stimulus presentation. The maximum amplitude of change in OxyHb concentration over 10 seconds was significantly lower in both POAG and PACG groups compared with control in the right and left middle occipital gyri ( P < 0.05). There was no significant difference between PACG and POAG. Importantly, there was a negative correlation between the visual cortex activity with the visual field defects (mean deviation; P < 0.05) and a positive correlation with retinal nerve fibre layer thickness in the glaucoma group ( P < 0.05).

CONCLUSION

In patients with glaucoma, a reduction in visual cortical activity was observed, which may be indicative of neuronal degeneration occurring in the occipital cortex. Disease severity in glaucoma appears to be closely correlated with visual cortex activity. fNIRS can serve as a useful neuroimaging modality for assessing the hemodynamic and neurodegenerative changes in glaucoma.

Effect of various relaxation techniques on the intraocular pressure of patients with glaucoma: systematic review and meta-analysis

OBJECTIVE

To conduct a systematic review focusing on the impact of various relaxation techniques on the intraocular pressure of patients with glaucoma.

METHODS

A systematic literature search was performed through CINAHL, MEDLINE, EMBASE, ClinicalTrials.gov, ProQuest Dissertations and Theses Global, and conferences until July 2022. Covidence software (Veritas Health Innovation, Melbourne, Australia) was used to conduct the systematic review. The screening was done by 2 independent reviewers, and a risk-of-bias assessment was completed after data extraction. Stata Statistical Software, version 14 (StataCorp LLC, College Station, Texas) was used to conduct a meta-analysis.

RESULTS

Twelve articles (596 subjects) were included for qualitative analysis and 5 articles (332 subjects) for quantitative analysis. One hour of daily mindfulness meditation for 3 weeks resulted in the most significant reduction in intraocular pressure (IOP) at 31.8%. Meditation consistently caused long-term reductions in IOP (standardized mean difference = -2.02; range, -3.16 to -0.89). Autogenic relaxation exercises showed a trend toward reducing IOP acutely but a significant reduction in the long term. Ocular relaxation exercises combined with visual imagery of aqueous humour drainage showed both acute and long-term reductions in IOP. The effects of yoga on IOP could depend on the positions being practiced.

CONCLUSION

Various relaxation techniques, such as meditation, visual imagery, autogenic relaxation exercises, and ocular relaxation exercises, seem to cause significant reductions in IOP. Future randomized, controlled trials should be carried out to further explore the utility of these techniques for patients with glaucoma.

Reversing Aging and Improving Health Span in Glaucoma Patients: The Next Frontier?

How to cite this article: Dada T, Mahalingam K, Bhartiya S. Reversing Aging and Improving Health Span in Glaucoma Patients: The Next Frontier? J Curr Glaucoma Pract 2024;18(3):87-93.

The Clinical Efficacy of Different Relaxation Exercises on Intraocular Pressure Reduction: A Meta-Analysis

Objective: The aim of this study was to synthesize the available evidence on the clinical efficacy of different relaxation exercises on intraocular pressure (IOP) reduction. Methods: A systemic search of PubMed, Embase, Cochrane CENTRAL, and Web of Science was undertaken from the earliest record to 10 April 2024. Peer-reviewed studies that reported on healthy individuals and glaucoma patients engaging in relaxation exercises for at least three weeks were included. The primary outcome was changes in IOP levels from baseline, before the commencement of relaxation exercises, to post-exercise. Our statistical analysis employed a random-effects model, with effect sizes reported using Hedges' g. Results: Twelve studies were included, totaling 764 eyes (mean participant age ranging from 21.07 to 69.50 years). Relaxation exercises significantly reduced IOP, with Hedges' g being -1.276 (95% CI: -1.674 to -0.879) and I2 = 84.4%. Separate subgroup analyses showed that breathing exercises (Hedges' g = -0.860, p < 0.0001), mindfulness-based stress reduction (MBSR) (Hedges' g = -1.79, p < 0.0001), and ocular exercises (Hedges' g = -0.974, p < 0.0001) were associated with reduced IOP levels. The reduction in IOP following the relaxation exercises was found to be associated with baseline IOP either greater than (Hedges' g = -1.473, p < 0.0001) or less than 21 mmHg (Hedges' g = -1.22, p < 0.0001). Furthermore, this effect persisted with follow-up durations of less than (Hedges' g = -1.161, p < 0.0001) and more than one month (Hedges' g = -1.324, p < 0.0001). Conclusions: The current meta-analysis indicates that relaxation exercises can significantly reduce IOP levels. Relaxation exercises are a potential class of novel treatments for glaucoma patients that deserve further evaluation.

The impact of intraocular pressure on optical coherence tomography angiography: A review of current evidence

A scoping review of 45 peer-reviewed manuscripts involving intraocular pressure (IOP) change and concurrent optical coherence tomography angiography (OCTA) assessments was performed to aggregate knowledge, summarize major findings, and identify gaps in literature and methodology relating to the effect of IOP change on OCTA. Articles were identified through PubMed/Medline, Google Scholar, Cochrane, Web of Science, and article reference lists. A total of 838 results were identified, and 45 articles met the inclusion and exclusion criteria for detailed analysis. OCTA metrics including vessel density (VD), perfusion density, and flow density of the superficial capillary plexus and the radial peripapillary capillaries were analyzed in relation to relative temporal IOP changes. Overall, IOP changes were found to affect superficial vascular plexus (VD) measurements on OCTA, especially when IOP elevated above the physiologic normal range (10-21 mmHg). No significant association was found between diurnal IOP variation and OCTA metrics. Cataract surgery improved the whole-image signal strength and VD regardless of changes in IOP. Beta-blockers were associated with paradoxically reduced vessel density in normal tension glaucoma patients in two studies. Although glaucoma surgical intervention studies were inconsistent and limited by scan quality and low sample sizes, patients requiring glaucoma surgery exhibited attenuated postoperative superficial VD recovery despite significant IOP reductions with surgical intervention. In addition to ensuring near-perfect signal strength with minimal media opacities and controlling for high myopia, central corneal thickness, and the presence of retinopathy, clinicians should consider the statistically significant impact of IOP on OCTA metrics when interpreting results.

Effect of "365 Breathing Technique" on Intraocular Pressure and Autonomic Functions in Patients With Glaucoma: A Randomized Controlled Trial

PRCIS

Patients with primary open angle glaucoma were advised to follow the "365 breathing technique" for 6 weeks in addition to their pharmacological glaucoma treatment. It helped to reduce intraocular pressure (IOP), stress biomarker-cortisol, and improve autonomic dysfunction.

OBJECTIVE

To study the effect of the "365 breathing technique" on IOP, autonomic functions, and stress biomarkers in patients with primary open angle glaucoma.

METHODS

In this randomized, controlled, interventional trial, after randomization, 40 patients in the intervention group followed "365 breathing" (three times a day, breathing rate: 6 cycles/min for 5 min) in addition to their pharmacological glaucoma treatment and 40 patients in the control group continued only with their pharmacological glaucoma treatment. IOP, serum cortisol, heart rate variability (HRV), and heart rate response to deep breathing test (DBT) were recorded at preintervention and 6 weeks postintervention.

RESULTS

The mean IOP, serum cortisol, parameters of the HRV test, and DBT were comparable between the two groups at baseline. At the 6-week follow-up, in the intervention group, mean IOP was significantly lower (16.09 ± 2.24 vs 18.38 ± 1.58 mm Hg, P = 0.03) and serum cortisol were significantly lower (13.20 ± 3.11 vs 14.95 ± 2.60 mcg/dL, P = 0.038) compared with the control group. In the HRV test, time domain analysis showed a significant difference in the root mean square of the successive difference between RR interval values between both groups at 6 weeks ( P = 0.015) pointing towards higher postintervention parasympathetic activation in the intervention group. In frequency domain analysis (HRV test), the ratio of the low-frequency component to the high-frequency component was significantly lower in the intervention group at 6 weeks (1.65 vs 1.79, P = 0.019) indicating a shift in sympathovagal balance towards greater vagal modulation.There was a significant increase in delta heart rate ( P = 0.019) and expiratory:inspiratory ratio ( P = 0.011) in the intervention group at 6 weeks when compared with baseline values, indicating improved parasympathetic reactivity to DBT.

CONCLUSION

"365 breathing" technique can reduce IOP and serum cortisol, and improve autonomic dysfunction in patients with glaucoma.

Stress and Allostatic Load in Patients With Primary Open Angle Glaucoma

PRCIS

This study evaluated the allostatic load (AL) in primary open angle glaucoma (POAG) patients and reported that the AL score was significantly higher in glaucoma patients compared with age-matched controls.

PURPOSE

To evaluate the AL in patients with POAG.

METHODS

This case-control study comprised 50 POAG (glaucoma patients) and 50 age-matched controls without glaucoma (controls). AL was estimated based on 13 variables: systolic blood pressure (BP), diastolic BP, homocysteine, triglycerides, total cholesterol, high-density lipoprotein, low-density lipoprotein, body mass index, serum cortisol, glycosylated hemoglobin, albumin, creatinine clearance, and C-reactive protein. High-risk thresholds were determined based on biological cutoffs of each biomarker. One point was assigned for each biomarker reading above cutoff and were summated to obtain AL score; score ≥4 was considered high.

RESULTS

Mean age of glaucoma patients was 60.82±6.26 and 60.14±6.72 years in controls ( P =0.602). All components of AL score (except C-reactive protein) had higher values in glaucoma patients. There was a statistically significant difference in homocysteine ( P =0.001), total cholesterol ( P =0.037), high-density lipoprotein ( P =0.005), and glycosylated hemoglobin ( P =0.003). Mean AL score was 4.68±2.09 in glaucoma patients and 3.32±1.34 in controls ( P <0.001). There was significant association of high AL score with older age ( P =0.006), low socioeconomic status ( P =0.020), and glaucoma severity ( P =0.001). Negative correlation was seen between AL and retinal nerve fiber layer thickness (Right Eye: r =-0.37, P <0.001; Left Eye: r =-0.298, P <0.001) and visual field mean deviation (Right Eye: r =-0.469, P <0.001; Left Eye: r =-0.520, P <0.001).

CONCLUSIONS

Glaucoma patients exhibited allostatic overload indicating physiological dysregulation to chronic stress although additional research is required to establish causality. A holistic approach with lifestyle modifications to reduce chronic stress should be an integral part of managing glaucoma patients as it would serve both to possibly reduce or prevent disease progression and improve overall health outcomes.

Towards modifying the genetic predisposition for glaucoma: An overview of the contribution and interaction of genetic and environmental factors

Glaucoma, the leading cause of irreversible blindness worldwide, is a complex human disease, with both genetic and environmental determinants. The availability of large-scale, population-based cohorts and biobanks, combining genotyping and detailed phenotyping, has greatly accelerated research into the aetiology of glaucoma in recent years. Hypothesis-free genome-wide association studies have furthered our understanding of the complex genetic architecture underpinning the disease, while epidemiological studies have provided advances in the identification and characterisation of environmental risk factors. It is increasingly recognised that the combined effects of genetic and environmental factors may confer a disease risk that reflects a departure from the simple additive effect of the two. These gene-environment interactions have been implicated in a host of complex human diseases, including glaucoma, and have several important diagnostic and therapeutic implications for future clinical practice. Importantly, the ability to modify the risk associated with a particular genetic makeup promises to lead to personalised recommendations for glaucoma prevention, as well as novel treatment approaches in years to come. Here we provide an overview of genetic and environmental risk factors for glaucoma, as well as reviewing the evidence and discussing the implications of gene-environment interactions for the disease.

Three potential neurovascular pathways driving the benefits of mindfulness meditation for older adults

Mindfulness meditation has been shown to be beneficial for a range of different health conditions, impacts brain function and structure relatively quickly, and has shown promise with aging samples. Functional magnetic resonance imaging metrics provide insight into neurovascular health which plays a key role in both normal and pathological aging processes. Experimental mindfulness meditation studies that included functional magnetic resonance metrics as an outcome measure may point to potential neurovascular mechanisms of action relevant for aging adults that have not yet been previously examined. We first review the resting-state magnetic resonance studies conducted in exclusively older adult age samples. Findings from older adult-only samples are then used to frame the findings of task magnetic resonance imaging studies conducted in both clinical and healthy adult samples. Based on the resting-state studies in older adults and the task magnetic resonance studies in adult samples, we propose three potential mechanisms by which mindfulness meditation may offer a neurovascular therapeutic benefit for older adults: (1) a direct neurovascular mechanism via increased resting-state cerebral blood flow; (2) an indirect anti-neuroinflammatory mechanism via increased functional connectivity within the default mode network, and (3) a top-down control mechanism that likely reflects both a direct and an indirect neurovascular pathway.

Daily Meditation Practice for Managing Glaucoma- patients' Attitudes and Acceptance

PRECIS

63% of glaucoma patients agreed to 45-60 minutes of daily meditation. Predictors of accepting meditation included previous meditation practice, a diagnosis of glaucoma <1 year, and having a marital status of "single".

PURPOSE

To explore patients' acceptance and barriers towards 45-60 minutes daily meditation for glaucoma management and to identify glaucoma patients with higher perceived stress levels who may benefit more from meditation practice.

METHODS

Glaucoma patients attending the Royal Victorian Eye and Ear Hospital, Melbourne, Australia outpatient department were invited to complete a patient survey. This explored if patients would agree to 45-60 minutes of daily meditation and included the Determinants of Meditation Practice Inventory and Perceived Stress Scale questionnaires. Questionnaire scores were compared across participants' clinical and demographic characteristics using student's T-Test, ANOVA, and multiple-linear-regression analysis.

RESULTS

Of the 123 eligible patients screened, one hundred completed the survey (81.3%). Sixty-three (63%) patients would agree to 45-60 minutes of daily meditation if advised by their doctor. Univariate analysis showed increased acceptance of meditation (lower Determinants of Meditation Practice Inventory scores) to be associated with agreeing to meditate 45-60 minutes daily (P=0.002), currently or previously practicing meditation (P=0.006 and P=0.0004 respectively), and having a marital status of "single" (P=0.02). Multi variate regression analysis showed previous meditation practice and a glaucoma diagnosis of <1 year to be predictive of accepting meditation (P=0.01 and P=0.03 respectively). There were no predictive factors of Perceived Stress Scale scores.

CONCLUSION

Given the high acceptance rate of 45-60 minutes daily meditation (63% of glaucoma patients sampled), this may be recommended for benefit of patients. Patients who have previously meditated, have a relatively new diagnosis of glaucoma, and are single (marital status) were more accepting of meditation practice.