Assessing the Impact of Cataract Surgery on Progression from Dry to Neovascular Age-Related Macular Degeneration: Insights from the IRIS® Registry

Highlight

A recent analysis of over 80,000 eyes with dry age-related macular degeneration (dAMD) demonstrated a modestly increased risk of progression to neovascular AMD (nvAMD) following cataract surgery (CS). The increased risk was most pronounced within the first year post-surgery and diminished over time, suggesting surveillance bias and pre-existing pathology rather than a prolonged biological effect. These findings reinforce the need for careful assessment of dAMD patients perioperatively but do not contraindicate cataract surgery based on fears of accelerating nvAMD conversion.

Study Background and Disease Burden

Age-related macular degeneration (AMD) is a leading cause of irreversible vision loss in the elderly, primarily affecting central vision through progressive degeneration of the macula. AMD exists in two main forms: dry (non-neovascular) and neovascular (wet) AMD. Dry AMD is characterized by gradual retinal deterioration, while neovascular AMD (nvAMD) involves pathological choroidal neovascularization and is associated with rapid vision loss if untreated.

Patients with dry AMD often develop cataracts concurrently given overlapping age demographics. Cataract surgery (CS) is the most effective intervention to restore vision impaired by lens opacification. However, concerns have persisted about whether CS might increase the risk of conversion from dry to neovascular AMD, potentially leading to accelerated vision loss. Clarifying this relationship remains critical for clinical decision-making in patients harboring early or intermediate dry AMD who require cataract surgery.

Study Design

This investigation utilized the American Academy of Ophthalmology’s IRIS® (Intelligent Research in Sight) Registry, a large real-world ophthalmology clinical database, to conduct a population-based retrospective cohort study. The study population comprised eyes from patients aged ≥55 years diagnosed with early or intermediate dry AMD and possessing a phakic lens at baseline between 1 January 2016 and 31 December 2022.

Eyes undergoing cataract surgery during follow-up were categorized as exposed; those without surgery served as nonexposed controls. To reduce confounding, 1:1 propensity score matching balanced covariates including age, sex, race, ethnicity, laterality, AMD severity, and smoking status. Cataract surgery was analyzed as a time-varying exposure within Cox proportional hazards models estimating the hazard of conversion to neovascular AMD, defined via ICD diagnosis codes within the registry.

Key Findings

After matching, the study analyzed 40,053 eyes in each group (total 80,106 eyes). Cataract surgery was associated with an overall modestly increased risk of progression to nvAMD (hazard ratio [HR] 1.22, 95% confidence interval [CI] 1.16–1.30, p < 0.001).

The temporal pattern of this risk was notable: the highest hazard occurred within the first postoperative year (HR approximately 2.5), steadily declining during subsequent years and becoming non-significant after year 4. By six years, the cumulative incidence of nvAMD was 17.7% in eyes undergoing cataract surgery versus 15.2% in controls, amounting to an absolute risk difference of approximately 3.3%.

Baseline AMD stage influenced the impact of surgery, with intermediate dry AMD exhibiting a weaker association with subsequent conversion (interaction HR = 0.82, 95% CI 0.78–0.92), suggesting disease severity modulates risk. This nuanced relationship supports varying surveillance intensity based on AMD stage.

Expert Commentary

These findings align with prior observations suggesting that the association between cataract surgery and progression to nvAMD is likely confounded by increased postoperative surveillance and pre-existing, subclinical neovascularization rather than a direct causal effect of the surgical intervention. The initially heightened hazard shortly after surgery may reflect detection bias, as patients undergo more frequent examinations postoperatively.

Importantly, the modest absolute risk increase (~3.3% over six years) is unlikely to outweigh the visual benefits of cataract extraction for the majority of patients. This study underscores the need for thorough preoperative retinal assessment using multimodal imaging in dry AMD patients scheduled for surgery and vigilant postoperative monitoring for early signs of neovascularization.

Nevertheless, limitations include reliance on registry diagnostic codes without centralized imaging confirmation, potential residual confounding, and lack of granular data on systemic and ocular risk factors such as genetic predisposition or precise smoking intensity.

Conclusion

The IRIS® Registry analysis confirms that cataract surgery is associated with a modest and time-limited increased risk of conversion from dry to neovascular AMD, largely attributable to enhanced surveillance and pre-existing undiagnosed nvAMD rather than a direct biological effect of the surgery. The absolute difference in risk is small and should not deter clinicians from recommending cataract extraction when indicated. Meticulous perioperative retinal evaluation and patient counseling remain essential to optimize outcomes in this growing patient population.

Funding and ClinicalTrials.gov

The study was conducted by the IRIS® Registry Analytic Center Consortium with no stated external funding. ClinicalTrials.gov registration was not applicable as this was a retrospective database study.

References

1. Ashourizadeh H, Gilbert JB, Ross C, et al. Cataract Surgery and the Risk of Conversion from Dry to Neovascular Age-related Macular Degeneration in the IRIS© Registry. Ophthalmology. 2026 Jun 22. PMID: 42331067.
2. Klein R, Klein BEK, Linton KLP. Cataract and age-related macular degeneration. The Beaver Dam Eye Study. Arch Ophthalmol. 1992;110(8):1067–1070.
3. Chew EY, Clemons TE, Agrón E, et al. Long-Term Effects of Age-Related Macular Degeneration on Visual Function After Cataract Surgery. Ophthalmology. 2014;121(6):1299-1304.