Glaucoma is an optic neuropathy characterized by progressive degeneration of retinal ganglion cells and visual field loss 4). The optic nerve damage and visual impairment caused by glaucoma are irreversible, and the primary goal of treatment is to preserve current visual function. The prevalence in individuals aged 40 years or older is 5.0% (Tajimi Study), with an estimated 4.65 million affected individuals 1). Furthermore, the same epidemiological survey found that 89% of glaucoma cases were newly detected, indicating a large number of untreated glaucoma patients 1).
In primary open-angle glaucoma (POAG), lifelong medication is assumed. Treatment primarily focuses on lowering intraocular pressure, starting with monotherapy and limiting combination therapy to a maximum of two drugs when possible. Drug selection should consider target intraocular pressure, side effects, frequency of instillation, and patient preference. Even with slow progression, complete arrest is rare, and treatment plans must accommodate gradual long-term progression. Younger patients have longer life expectancy and require more aggressive treatment and management with a higher estimated severity.
While POAG alone rarely leads to extremely severe visual impairment, it has been reported that POAG patients constitute the highest proportion among glaucoma patients visiting low-vision clinics. Treatments targeting factors other than intraocular pressure, such as circulation improvement and neuroprotection, are also considered, but intraocular pressure reduction remains the most reliable treatment at present.
Intraocular pressure is the only modifiable risk factor for glaucoma, and its management is fundamental to treatment 2)4). Other reported risk factors include 4)5):
Beros et al. (2024) reported that arterial stiffness measured by a simple oscillometric device may predict the development of glaucoma. The HR per 1 standard deviation increase in aPWV was 1.36 (95% CI 1.14-1.62), suggesting that arteriosclerosis could be a new risk marker for glaucoma7).
Glaucoma cannot be cured by lifestyle changes alone. Glaucoma is an irreversible optic neuropathy, and intraocular pressure management through medication, laser treatment, or surgery is the mainstay of treatment. However, moderate exercise and a balanced diet may contribute adjunctively to intraocular pressure control and are important as part of overall health management.
Non-adherence rates in glaucoma treatment are reported to be 30–80%. Approximately 40% of patients who are prescribed glaucoma eye drops for the first time discontinue treatment within about one year1). This is attributed to the lack of subjective symptoms and the absence of feedback on treatment effectiveness except during clinic visits1). Poor adherence is a major factor in glaucoma progression, and it is desirable to select medications and dosing frequencies that are not only effective but also easy to continue1).
Obtaining the Medication
Cost burden: When drug prices are high, obtaining the medication itself becomes difficult. Using generic drugs is effective.
Early refill issues: Instilling more than one drop can cause the medication to run out sooner than expected.
Proper Instillation
Physical limitations: Reduced grip strength due to rheumatic or neurological diseases, and limited neck extension, make instillation difficult.
Bottle operability: The force required to dispense one drop varies by bottle. Multiple drops may be used or wasted.
Daily Maintenance
Forgetfulness: This is especially problematic for elderly patients with multiple chronic conditions.
Asymptomatic nature: Since most cases are asymptomatic, some patients do not feel the need to instill drops daily.
Side effects: Some patients discontinue use if local side effects (e.g., redness, pigmentation) are not explained.
In elderly patients, poor instillation technique and forgetting to instill are major causes of reduced adherence. Many elderly patients have difficulty tilting their head back due to spinal deformities, so instructing them to instill while lying down improves success rates.
The current first-line treatment is prostaglandin analogs (PGAs), which are the most widely used due to their excellent intraocular pressure-lowering effect and once-daily dosing 1). Second-line options include beta-blockers, but in cases where systemic side effects are a concern, such as in elderly patients, beta-blockers should be avoided and alternatives such as CAIs (carbonic anhydrase inhibitors), alpha-2 agonists, or ROCK inhibitors should be selected.
Five fixed-combination eye drops are available, allowing multiple medications to be administered without increasing the number of drops or frequency, which helps maintain adherence 1). However, forgetting to use a fixed-combination drop results in a greater loss of intraocular pressure-lowering effect compared to single agents, making adherence monitoring even more important.
There are useful assistive devices for patients with physical limitations.
| Type of Assistive Device | Purpose | Features |
|---|---|---|
| Eye drop guide | Alignment | Fixes lower eyelid and guides gaze |
| Bottle aid | Grip assistance | Clip-on type |
| Drop volume adjuster | Reduction of waste | Reduces drop volume by 60% or more |
To make it easier to continue eye drops, combine the following supports1):
Evidence shows that written explanations/delivery, visit management, and reminder notifications significantly improve treatment continuation rates1). The EGS 6th edition also recommends simplification, education, effective communication, and use of alarms/messages2).
When intraocular pressure control is insufficient or visual function impairment progresses, it is necessary to reassess adherence 1). In cases where drug therapy cannot be properly administered due to side effects or poor adherence, laser treatment or invasive surgery may be options 1).
Fixed-combination eye drops can deliver two drug components in a single bottle, reducing the number of eye drops and instillation frequency. They are considered useful for improving adherence when multiple medications are used. However, the loss of intraocular pressure-lowering effect when a dose is missed is greater than with single agents, making adherence monitoring even more important.
Recommended Exercises
Walking and cycling: Mild intraocular pressure increase during activity, followed by sustained pressure reduction afterward
Running: Intraocular pressure decreases by approximately 2 mmHg, but returns to baseline within 30 minutes after exercise ends
Suppression of visual field progression: Each 5,000 steps of walking or 2.5 hours of non-sedentary activity per day reduces visual field progression by 10%
Retinal protective effect: Increased physical activity slows the thinning rate of the ganglion cell-inner plexiform layer
Exercises Requiring Caution
Weightlifting: Isometric holds cause temporary intraocular pressure elevation. Reports indicate it can reach approximately 41 mmHg during leg press
Yoga (inverted poses): Poses where the head is lower than the heart (e.g., downward dog) significantly increase intraocular pressure. Handstands can roughly double intraocular pressure
High-intensity workouts: Daily vigorous exercise is associated with a higher prevalence of glaucoma compared to three days per week. Increased free radicals and oxidative stress may be involved
Swimming goggles: Can cause temporary but marked intraocular pressure elevation while worn
In a study of patients newly diagnosed with glaucoma, a group that exercised for 30 minutes daily showed a significant reduction in intraocular pressure compared to a medication group. It has been reported that each 10-minute increase in evening activity reduces the odds of visual field progression in POAG patients by 15%. Increased physical activity has also been associated with a slower rate of thinning of the ganglion cell-inner plexiform layer, suggesting that exercise may have neuroprotective effects beyond lowering intraocular pressure.
However, the 6th edition of the EGS states that “there is currently no strong evidence that dietary or lifestyle factors affect glaucoma” 2), and lifestyle modifications are considered only adjunctive. It is important to consult with your doctor regarding the type, intensity, and timing of exercise, and to make decisions based on individual medical conditions.
It is not necessary to avoid all yoga, but poses where the head is lower than the heart, such as “downward dog,” “forward bend,” and “headstand,” are recommended to be avoided as they significantly increase intraocular pressure. Caution is especially needed in patients at high risk of progression. Poses performed while sitting or standing are usually not a problem.
Dietary nitrate, abundant in green leafy vegetables, is converted to nitric oxide in the body. Nitric oxide is thought to protect against glaucoma through vasodilation, increased aqueous humor outflow, and decreased episcleral venous pressure. Large cohort studies (e.g., Nurses’ Health Study) have shown that groups with higher dietary nitrate intake have a 20–30% lower risk of developing POAG.
Omega-3 fatty acids (EPA and DHA) regulate systemic microcirculation and ocular blood flow. A prospective study of patients with pseudoexfoliation glaucoma found a significant reduction in intraocular pressure after six months of oral DHA supplementation. However, a high ratio of omega-3 to omega-6 may increase glaucoma risk, and conclusions remain inconclusive.
Key findings are summarized below.
| Nutrient | Key Findings |
|---|---|
| Vitamin B3 (Niacinamide) | Prevents mitochondrial dysfunction and provides neuroprotection |
| Flavonoids | Improvement in mean deviation of visual field |
| Vitamin A | Suggestive association between intake and glaucoma risk9) |
Vitamin B3 (nicotinamide) reduces vulnerability to glaucoma in mouse models, and clinical trials have shown improvement in inner retinal function. However, there is currently insufficient evidence that any specific vitamin supplement reduces the risk of glaucoma. The EGS 6th edition states that evidence supporting the role of alternative therapies or neuroprotective agents in glaucoma management is insufficient2).
Alcohol consumption temporarily lowers intraocular pressure, but chronic intake may increase the risk of open-angle glaucoma by 1.18 times. It was classified as “weak evidence” in an umbrella review9). The certainty of the evidence is very low.
Caffeine intake is not associated with increased intraocular pressure in healthy individuals, but in patients with a history of glaucoma or ocular hypertension, it is associated with a temporary increase of about 2.4 mmHg one hour after consumption. In patients with a family history of glaucoma or genetic predisposition, an association between caffeine intake and glaucoma prevalence has been suggested.
Moderate coffee consumption is generally considered not a major problem. However, in patients with glaucoma or ocular hypertension, a temporary increase in intraocular pressure (about 2.4 mmHg) after caffeine intake has been reported. Especially for those with a family history of glaucoma or insufficient intraocular pressure control, it is advisable to avoid large amounts of caffeine (more than 2–3 cups of coffee per day).
Intraocular pressure is affected by body position1). Key findings are as follows:
In normal individuals, IOP fluctuates by about 3–6 mmHg throughout the day1). In glaucoma patients, the fluctuation range is larger due to reduced aqueous humor outflow1). Peak IOP is often observed in the morning, and the lowest IOP in the evening to nighttime1).
Obstructive sleep apnea syndrome has been reported as a risk factor for glaucoma5). In an umbrella review, it was classified as having “suggestive evidence”9). However, this association is not consistently demonstrated in all studies4).
Smoking is considered one of the risk factors for glaucoma. It is thought to involve increased oxidative stress, impaired retinal microcirculation, and direct toxicity to the optic nerve. In an umbrella review, both current smoking and former smoking were classified as “non-significant”9), but considering the overall health effects, smoking cessation is recommended.
The odds of stopping driving double for every 5 dB worsening of visual field loss in the worse eye. Patients with advanced glaucoma have 3.5 times higher odds of being involved in a motor vehicle accident 4). Impairment of the useful field of view (UFOV) is the strongest risk factor for motor vehicle accidents 4).
In on-road driving tests, glaucoma patients with mild to moderate visual field impairment were able to complete the driving course but were 6 times more likely to require instructor intervention. In simulator studies, glaucoma patients exhibited significantly more saccades, fixations, and pursuit eye movements, and their gaze patterns did not change when hazards entered the visual field defect area.
When elderly patients visit the outpatient clinic, always confirm the following three items:
This information should be shared among all staff involved in outpatient care.
Progression of glaucoma itself may make eye drop or oral medication difficult, potentially leading to reduced treatment accuracy for other diseases. Maintaining QoL is one of the most important goals in glaucoma care, and comprehensive life support including securing means of transportation is required 1). The 6th edition of the EGS also notes that patients are often confused about local regulations regarding glaucoma and driving, and recommends providing appropriate information 2).
The goal of glaucoma management is to minimize visual impairment and promote the best possible quality of life (QoL) within a sustainable healthcare system 2). While early to moderate glaucoma has a limited impact on QoL, advanced visual function loss in both eyes significantly reduces QoL 2).
Contrast sensitivity is an important predictor of the ability to perform activities of daily living 6). Even in glaucomatous eyes with visual acuity of 20/40 or better, contrast sensitivity is significantly reduced (correlation with visual field MD: r=0.638, P<0.05), and visual acuity alone cannot predict the degree of functional impairment 6). Recent studies have shown that macular damage is more common in early glaucoma than previously thought 6).
Several scales are available to assess the impact of visual function on QoL.
| Assessment Scale | Number of Items | Type |
|---|---|---|
| NEI-VFQ 25 | 25 items | Self-report |
| GSS | 10 items | Self-report |
| GQL-15 / GAL-9 | 15 questions / 9 questions | Self-report |
| ADREV | 9 tasks | Performance-based |
| UFOV | — | Performance-based |
Self-report scales
Advantages: Easy to administer. Reflects the patient’s subjective perception
Disadvantages: Has reporting bias. Disability may be underreported if tasks are avoided
Representative examples: NEI-VFQ, GSS, GQL-15/GAL-9
Direct measurement scales
Advantages: Can be tested under standardized conditions. Less susceptible to reporting bias
Disadvantages: Difficult to administer and burdensome for subjects. Cannot fully replicate real-world environments
Representative examples: ADREV, UFOV
Low vision centers and local disability support organizations assist visually impaired individuals in independent living.
Maintaining QoL is one of the most important goals in glaucoma care 1). As glaucoma progresses, eye drop and oral medication administration may become difficult, and this can also affect the accuracy of treatment for other diseases 1). To preserve patients’ QoL, it is necessary not only to treat the disease but also to consider the psychological impact of diagnosis and treatment on patients and their families 1).
The most frequent complaint is difficulty performing tasks under low or high illumination. Reading difficulty is observed even in moderate glaucoma with normal visual acuity, and is more pronounced with small or low-contrast text. Reduced walking speed and balance problems lead to an increased risk of falls. Driving ability is also significantly affected, with the risk of accidents increasing 3.5-fold in advanced cases. These impairments are primarily caused by reduced contrast sensitivity and visual field defects.
In the 6-year results of the LiGHT trial, 69.8% of the SLT (selective laser trabeculoplasty) group maintained target intraocular pressure without eye drops 8). Compared to the eye drop group, the rate of visual field progression was lower (19.6% vs 26.8%, P=0.006), and fewer cases required trabeculectomy (13 eyes vs 32 eyes, P<0.001) 8). SLT is particularly useful for patients with adherence issues as a treatment option that does not rely on eye drops.
As an alternative to daily eye drops, intracameral implants of bimatoprost and travoprost are being developed. They are expected to be an option for patients who have difficulty with eye drops, but long-term efficacy and safety need to be confirmed.
Nicotinamide (the amide form of vitamin B3) has attracted attention for its neuroprotective effects in glaucoma. In a clinical trial by De Moraes et al., the combination of nicotinamide and pyruvate was associated with improvement in pattern standard deviation compared to placebo. Although a protective effect via prevention of mitochondrial dysfunction is suggested, the EGS 6th edition does not yet recommend neuroprotective agents2).
The COVID-19 pandemic accelerated the introduction of telemedicine into glaucoma care. In a qualitative study by Liu et al. (2023), interviews with 20 glaucoma specialists working in NYC found that telemedicine utilization during the peak of the pandemic was 29.1%, but dropped sharply to 3.1% a few months later 10). The main reason was the difficulty of performing intraocular pressure measurements and visual field tests remotely, but optimistic views about future reintroduction due to technological innovations (e.g., home intraocular pressure monitoring devices) were also reported 10).
