Metformin Linked to Reduced Glaucoma Risk

A new study published in the Journal of Glaucoma suggested that lower dosages of Metformin may have a protective effect on OAG risk, but higher doses had no significant impact.

“The underlying mechanisms linking cumulative metformin dosage to OAG risk are not yet fully understood, highlighting the need for future prospective clinical trials to assess the potential benefits and risks of metformin treatment for OAG in DM patients,” they concluded in their paper. “Our analysis highlights that comorbidities such as hyperthyroidism, myopia and cataract play a more substantial role in elevating OAG risk compared to DM itself or metformin use. These findings underscore the importance of considering coexisting conditions in the management of OAG risk among DM patients, suggesting that the influence of metformin may be secondary to these underlying factors.”

Huang SW Lai YR, Yang Y, Gau SY, Chung NJ, Tsai TH, Huang KH, Lee CY. Association between long-term metformin use and risk of open-angle glaucoma in patients with diabetes mellitus. Journal of Glaucoma. May 16, 2025.

Diabetic Retinopathy Risk Peaks at a Hemoglobin A1c of 9.4, Then Declines at HIgher Levels

 

HbA1c level is known to be indicative as a critical biomarker for long-term glycemic control and is linked to risk of diabetic retinopathy development.

Researchers recently published a paper in BMC Ophthalmology in which HbA1c levels were measured and the association between this and DR was analyzed.

HbA1c positively correlated with DR; however, this was demonstrated by an inverted, U-shaped association, in which DR risk reached a peak of 9.4% with HbA1c level, then started to decline.

The authors explain that they found every 1% increase in HbA1c to be associated with a 7% increase in the odds of developing DR;

The investigators say, “Patients near the 9.4% HbA1c threshold need closer monitoring and timely intervention. For patients above 9.4%, consider aggressive glycemic control with complication monitoring.”

Ling J, Xie ZL, Chen XJ, et al. Inverted U-shaped relationship between HbA1c and diabetic retinopathy in diabetic patients: a cross-sectional study. BMC Ophthalmol. 2025;25:289.

Dipeptidyl Peptidase-4 Inhibitors (DPP4i, like Januvia) Lower Glaucoma Risk in Diabetic Patients

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In a recent study, researchers investigated the association between DPP4i and the risk of primary open-angle glaucoma and normal-tension glaucoma in diabetes patients; they found patients on this drug had a significantly lower risk compared to users of first-generation diabetes medication, such as metformin, among others. 

“These antioxidative properties, combined with their ability to remodel ocular connective tissue, may explain the associations observed in our study,” the authors wrote in their paper. “This suggests that DPP4i may mitigate some of the oxidative toxicity as well as structural changes associated with glaucoma progression.”

Overall, these findings suggest that DPP4i drugs may offer benefits beyond glycemic control, possibly influencing optic nerve health through multiple mechanisms. Further research is needed to explore the underlying mechanisms and their implications for glaucoma prevention and management, the authors concluded.

Lu Y-A, Tien P-T, Cheng Y-D, et al. Association of dipeptidyl peptidase-4 inhibitors with glaucoma risk in patients with type 2 diabetes: a nationwide cohort study. Ophthalmol Sci. May 8, 2025.

SLEEP APNEA AND DRY EYE

 

It's been shown that obstructive sleep apnea doesn’t just affect sleep—the condition may also affect ocular health, including dry eye disease (DED). In a recent study presented at ARVO 2025 in Salt Lake City, researchers examined whether people with sleep apnea are more likely to have DED; they found that dry eye was indeed significantly more common in people with the condition, even after accounting for other health issues like diabetes and obesity—suggesting a strong connection between the two conditions.

Obstructive sleep apnea was found to be significantly associated with a higher risk of DED. Obstructive sleep apnea patients were more likely to have obesity, diabetes, hypertension, hyperlipidemia, hypothyroidism and cardiovascular disease. A total of 17.9% of sleep apnea patients subjects showed evidence of dry eye, compared with  6.1% in matched controls.

Zhang A, He J, Ying G-S. Association of sleep apnea with dry eye disease in the All-of-Us Program. ARVO 2025 annual meeting.

Vitamin D Deficiency Increases Dry Eye Risk

In this study, patients deficient in vitamin D had a significantly higher incidence of dry eye disease 

The researchers wrote that “identifying and addressing vitamin D deficiency could lead to appropriately managing and potentially preventing dry eye syndrome.” 

Beauchamp BC, Shmushkevich S, Kane J, Bajrami S, Parekh P. The influence of vitamin D deficiency in the development of dry eye disease. ARVO 2025 annual meeting.

Low-Dose Insulin Useful for Puncate Epithelial Corneal Defects

Previous studies have determined that topical insulin use was effective in accelerating epithelial defect closure in patients with neurotrophic keratitis. When epithelialization is not achieved in two weeks with stan­dard initial treatment, this option would is an effective first-­line treatment option.  One study found that topical insulin is a safe and effective alternative to treat epithelial defects that don’t improve despite conventional treatment.

96.8% of eyes achieved closure of the epithelial defect with this treatment.

The average closure time was shorter in non-diabetics compared to diabetics. 9.3% experienced burning and 6.25% reported pain. 

Hernandez AJI, Gomez EA, Velasco R, et al. Effectiveness and safety of topical insulin in persistent epithelial defects refractory to treatment. ARVO 2025 annual meeting.

Exercise and Glaucoma

A recently published study in the Journal of Glaucoma reported slower rates of visual field loss in patients who exercised more.

In the analysis, the researchers found that slower visual field mean deviation loss was associated with active physical activity index category and higher physical activity amount. They found no significant associations between the rate of visual field mean deviation loss and baseline visual field mean deviation or walking pace. The multivariable analysis demonstrated an association between slower visual field mean deviation loss and higher amounts of physical activity.

"Physical activity is hypothesized to have neuroprotective effects on retinal ganglion cells,” the researchers explained adding that aerobic exercise has been found to temporarily reduce intraocular pressure while high-intensity resistance exercise and weightlifting can temporarily increase pressure. 

Cardiovascular Health and Macular Degeneration

 

Introduced by the American Heart Association in 2022, the Life’s Essential 8 score combines eight key metrics into a single holistic framework: diet, nicotine exposure, sleep duration, physical activity, body mass index, blood glucose, blood lipids and blood pressure. 

In a recent study, Chinese researchers explored relationship between cardiovascular health and macular degeneration, including the role of genetics, and found that maintaining good cardiovascular health can reduce AMD incidence regardless of genetic background. The findings were reported recently in Investigative Ophthalmology & Visual Science.

Individuals under 60 years of age showed a stronger beneficial association than those 60 and older, indicating that adopting good cardiovascular practices earlier can better reduce the incidence of AMD.

Subgroup analyses also showed a stronger beneficial association in women and nondrinkers. Regarding women, this could be attributed to several factors, including estrogen. Estrogen, with its antioxidant and anti-inflammatory properties, may enhance the benefits of cardiovascular health in women

An association was found between higher LDL and triglyceride concentrations and reduced AMD risk, showing these lipids “may play a protective role, potentially by supporting retinal health through lipid metabolism and membrane formation. Further investigation is needed in the relationship between LDL, triglycerides and AMD to uncover the exact mechanisms.

In addition to lifestyle modifications such as physical activity, a balanced diet and smoking cessation may help reduce the risk of AMD, 

VITAMIN D AND KERATOCONUS

 

Published in American Journal of Ophthalmology, the work by a research team from Italy reports observed the effects of vitamin D on keratoconus patients. 

The researchers discovered that vitamin D stabilizes the cornea and reduces keratoconus progression. 

Neuroretinal Rim Measurements Outperform RNFL Thickness for Detecting Glaucoma Progression

 

Monitoring structural changes (via disc photography and OCT) is helpful to catch glaucoma in its early stages, when intervention can be most effective in preventing major vision loss. A recent study, whose findings were published in Journal of Glaucoma, aimed to compare the efficacy of event-based vs. trend-based analysis in glaucoma detection.

The researchers performed both event-based and trend-based analyses and reported that the former method was significantly more effective at detecting glaucoma progression. 

Moreover, using high-density 3D OCT measurements of MDB neuroretinal rim thickness, event-based analysis detected progression in 52.4% of eyes tested, compared to only 9.7% detected by trend-based analysis using the same measurement.

The present study showed that event-based analysis using the MDB rim thickness parameter was a better test than RNFL thickness for detecting glaucoma progression over a five-year period,” 

Calcium Channel Blockers May Slow Visual Field Decline

 

The impact of calcium channel blockers on glaucoma remains a topic of debate, with some studies suggesting they may increase the risk of glaucoma and others indicating a protective effect.

In this study published in Ophthalmology Glaucoma researchers observed a potential protective association between calcium channel blocker use and visual field deterioration. But they suggested the need for further investigation.

DO ANTI-MYOPIA GLASSES WORK TO SLOW MYOPIC PROGRESSION?

Spectacle lenses containing highly aspherical lenslets have been shown to slow myopia progression. Chinese Researchers of this study found that 95% of children who wore anti-myopia glasses experienced myopia progression of less than 2.50D. 

Researchers concluded: “Therefore, long-term wear of highly aspherical lenslets eyeglass lenses could significantly reduce the incidence of high myopia.”

NEW ARTIFICIAL TEAR FOR DRY EYE COMES WITH PROMISES

 

Alcon recently released a new over-the-counter eyedrop, Systane Pro Preservative-Free (PF), formulated with an added hydrating agent to prolong symptom relief.

The multi-dose, triple-action solution contains the same ingredient (propylene glycol 0.6%), nano-sized lipids and hydroxypropyl guar as Systane Complete, another OTC artificial tear offered by Alcon. However, the new product’s formula is enhanced by the addition of hyaluronate, which the company says helps improve tear film retention on the ocular surface, provide sustained hydration, restore tear film stability and protect against further irritation of dry eyes, ultimately giving patients longer-lasting relief than that provided by other Systane drops on the market.

For more information, go to alcon.com.