Current Issue

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In this week’s issue

• In high-risk individuals, unhealthy lifestyle including smoking significantly increase progression to advanced age-related macular degeneration
• In older Asian adults, undiagnosed age-related eye diseases were common and associated with worse vision, quality of life, and higher healthcare costs.
• Tirzepatide was linked to lower risks of developing POAG, OHTN, and needing glaucoma treatment compared with selective GLP-1 receptor agonists.
• Gut microbiome changes were linked to retinitis pigmentosa, with antibiotics slowing degeneration in a mouse model.

Spotify Link:

https://open.spotify.com/episode/5eO5pWnueB3tcHu20MbHrp?si=BO6LLb4vQ0WoepnHOOvxdQ

Ophthalmology

Diet and lifestyle effects on progression to advanced AMD

Your health is your wealth but also your vision. Age-related macular degeneration (AMD) is a progressive disease affecting the macula and causes irreversible central vision loss. Previous studies have demonstrated that genetic risk factors can contribute to the heritability of up to 71% of advanced AMD (AAMD). Previous studies have reported that diet, gene, and lifestyle interactions are associated with AAMD. This prospective longitudinal study aimed to evaluate whether a high polygenic risk, calculated based on a genetic risk score (GRS), could be modified with lifestyle changes. Among 898 high-genetic-risk eyes, 207 (23%) progressed to AAMD. A high-risk lifestyle was associated with a 3-fold increase in AAMD incidence compared with an ideal health-promoting profile (HR: 3.3). While in ever smokers, there was a significant 5-fold risk of AAMD (HR: 5.3). In summary, unhealthy behaviors increased the incidence of AAMD by 3- to 5-fold among high-genetic-risk populations. These results underscore the importance of lifestyle modification for high-genetic-risk patients to slow AMD progression and preserve vision.he risk is low, clinicians should counsel patients on the risk of developing NAION upon initiation of semaglutide.

JAMA Ophthalmology 

Prevalence and risk factors for undiagnosed eye disease in Asian adults

What you don't know won't hurt you? Age-related macular degeneration (AMD), diabetic retinopathy (DR), cataract, and glaucoma remain leading causes of vision impairment globally. Yet contemporary data on how often these conditions go undiagnosed and what that means for patients have been limited in Asian populations. This was a cross-sectional study that used data from the Population Health and Eye Disease Profile in Elderly Singaporeans Study (PIONEER-1) and evaluated the prevalence of undetected eye disease and determined their common associated risk factors. The study included 1,878 participants and found that 35.8% had ≥1 undiagnosed eye disease(s). The prevalence for undiagnosed disease was 89.8% for AMD, 89.8% for DR, 40.8% for cataracts, and 48.1% for glaucoma. Younger age (OR 1.08), Malay or Indian ethnicity (OR 1.43), and multifocal glasses use (OR 1.75) were significantly associated with higher odds of having an undiagnosed eye disease compared to Chinese individuals. Individuals with undiagnosed eye disease also had poorer scores in health and vision-related quality of life (e.g, mobility, number of falls, etc.) compared with diagnosed individuals. Undiagnosed individuals also accrued 1.73 times higher health care expenditures. These findings reinforce the need for targeted community screening, particularly for younger seniors and high-risk ethnic groups like the Asian community to reduce preventable vision loss.

American Journal of Ophthalmology (AJO)

Tirzepatide and risk of glaucoma in patients with type 2 diabetes

Turns out tirzepatide might help your diabetes and your eyes. Glaucoma has a multitude of risk factors, such as elevated intraocular pressure (IOP), vascular dysregulation, oxidative stress, and neurodegeneration. The non-IOP-related mechanisms may be especially important in patients with type 2 diabetes as poor glycemic control has been linked to increased risk of glaucoma. Glucagon-like peptide-1 receptor agonists (GLP-1RAs) such as tirzepatide, which are highly effective in controlling glucose levels, weight loss, and improving cardiovascular outcomes, may also affect glaucoma risk. This retrospective cohort study used data from the TriNetX Analytics platform to compare the incidence of primary open-angle glaucoma (POAG), ocular hypertension (OHTN), and glaucoma treatments in two propensity score-matched cohorts of 41,849 adults with type 2 diabetes who started tirzepatide versus other GLP-1 RAs. Patients using tirzepatide had a significantly decreased risk of POAG (RR=0.50), OHTN (RR=0.59), and the necessity for glaucoma treatment (RR=0.54). This association was consistent across subgroup analyses, including older adults, patients using concomitant metformin or insulin, and individual GLP-1 RAs. These findings support an association between tirzepatide use and reduced risk of POAG and OHTN for patients with type 2 diabetes, suggesting possible neuroprotective effects of GLP-1 RAs.

.Investigative Ophthalmology & Visual Science (IOVS) 

How does the gut microbiome impact retinitis pigmentosa?

The problem may not just be in the eye but brewing in the gut. Retinitis pigmentosa (RP) is a group of inherited retinal degenerations characterized by progressive photoreceptor loss, leading to nyctalopia and eventual blindness. Many patients exhibit chronic intraocular inflammation, including cystoid macular edema (CME), which is associated with worse visual outcomes. Given the central role of the gut microbiome in immune and inflammatory regulation, this study investigated whether gut microbial composition is altered in RP and whether it contributes to retinal degeneration. The investigators performed 16S rRNA sequencing on stool samples from 103 patients with RP and 64 healthy controls, and further stratified RP patients by the presence or absence of CME. Patients with RP demonstrated significantly higher gut microbiota diversity compared with healthy individuals. Among RP patients, those with CME exhibited even greater microbial diversity and increased relative abundances of Romboutsia and Ruminococcus, suggesting an association between gut microbiota composition and inflammatory retinal complications. To test causality, the authors treated rd10 RP model mice with antibiotics to suppress the gut microbiome and compared them with untreated rd10 controls. Antibiotic-treated mice showed preserved retinal structure and function, including reduced photoreceptor apoptosis, decreased retinal thinning, and a lower incidence of retinal detachment. These effects were accompanied by downregulation of the NLRP3 inflammasome pathway, implicating microbiota-driven inflammation in disease progression. These findings support the existence of a gut-eye axis in RP, whereby gut microbiota-mediated inflammation contributes to retinal degeneration. Targeting this axis may represent a novel therapeutic strategy for modifying RP progression.

JAAPOS

Not all retinas mature on the same timeline

In ROP care, the calendar doesn’t always follow gestational age alone. Premature infants do not all reach retinal maturity on the same clock and understanding that timeline matters for family counseling and follow-up planning. Retinopathy of prematurity (ROP) is closely tied to disordered retinal vascular development, yet the factors influencing when complete vascularization occurs remain underexplored. In this retrospective cohort study at a single tertiary center in Iowa (2007-2020), investigators reviewed 1,971 infants screened for ROP and analyzed postmenstrual age (PMA) and chronological age at documented retinal maturity. Mean PMA at retinal maturity was 44.9 weeks, and delayed maturation was significantly associated with earlier gestational age at birth, greater ROP severity (stage 1 or higher, with further delay in stage 2-3), nonocular surgery, positive blood cultures, and ≥5 red blood cell transfusions, whereas prolonged ventilation, extended antibiotic use, and central line placement were not independently associated. These findings help refine expectations for ROP monitoring duration and highlight both ocular and systemic contributors to delayed retinal development.

ESCRS Study of Prophylaxis of Postoperative Endophthalmitis

If an apple-a-day keeps the doctor away, what keeps away endophthalmitis? While endophthalmitis is rare, invasion of the globe during cataract surgery is a risk factor and must be taken into consideration before, during, and after the procedure. In an effort to better understand ways to prevent such a postoperative complication, the ESCRS (European Society of Cataract and Refractive Surgeons) endophthalmitis study coordinated 24 ophthalmology clinics/units across Europe to gather data. Researchers in this partially masked, placebo-controlled, randomized clinical trial enrolled 13,698 participants to evaluate the prophylactic effect of intracameral cefuroxime injection and/or perioperative levofloxacin eyedrops on the incidence of endophthalmitis after cataract surgery.

Key Points

• Use of intracameral cefuroxime at the end of cataract surgery significantly reduced the risk of postoperative endophthalmitis.
• The total reported cases of endophthalmitis were nearly 5 times less in groups that utilized intracameral cefuroxime compared to those that did not (OR, 4.59; 95% CI, 1.74-12.08; P = 0.002).
• Cases of microbiologically proven endophthalmitis were more than 5 times less in groups that utilized intracameral cefuroxime compared to those that did not (OR, 5.32; 95% CI, 1.55-18.26; P = 0.008).

The ESCRS endophthalmitis study earns its landmark status as it was among the trailblazers of endophthalmitis prophylaxis as it relates to cataract surgery. The results of the study influenced surgical technique in the following years and widened the discussion on how to best prevent endophthalmitis after cataract surgery.