Studies show potential sequelae on diabetic eye from cataract surgery, GLP-1 use
One retrospective study found that progression to proliferative diabetic retinopathy was more likely after cataract surgery, while another showed that a modest increase in the risk of nonarteritic anterior ischemic optic neuropathy may be associated with the glucagon-like peptide-1 (GLP-1) receptor agonist semaglutide.
Common treatments were associated with negative outcomes on the eyes of patients with diabetes, two studies found.
The first study looked at the effects of cataract surgery on progression from diabetic nonproliferative diabetic retinopathy (NPDR), using a retrospective analysis of commercial data from June 2004 to June 2024 among adults with diabetes and NPDR who did or did not undergo routine cataract surgery. Outcomes included first-time diagnosis of progressive diabetic retinopathy (PDR), vitreous hemorrhage, tractional retinal detachment, and combined tractional and rhegmatogenous retinal detachment, as well as a composite outcome, compared at one year in patients who underwent cataract surgery and those who did not. Results were published Feb. 14 by Ophthalmology.
Of the 3,589 intervention patients who underwent surgery on the right eye, matched with an equal number of controls, there was a significantly increased risk of PDR without complications (hazard ratio [HR], 1.45; 95% CI, 1.09 to 1.92), vitreous hemorrhage (HR, 1.92; 95% CI, 1.13 to 3.25), and the composite outcome (HR, 1.49; 95% CI, 1.13 to 1.96). Left-eye analysis included 3,616 matched pairs and showed an increase in risk of PDR without complications (HR, 1.58; 95% CI, 1.17 to 2.13), vitreous hemorrhage (HR, 2.12; 95% CI, 1.23 to 3.66), and the composite outcome (HR, 1.60; 95% CI, 1.21 to 2.13) in operated eyes.
In a sensitivity analysis of 2,488 pairs of patients with diabetes of at least five years' duration, there was an increased risk of PDR without complications (HR, 1.52; 95% CI, 1.06 to 2.19), vitreous hemorrhage (HR, 2.50; 95% CI, 1.20 to 5.20), and the composite outcome (HR, 1.75; 95% CI, 1.22 to 2.51) in operated eyes. There was no significant difference in the risk for tractional retinal detachment or rhegmatogenous retinal detachment in any analysis.
“Our findings highlight the need for careful follow-up with a comprehensive examination in patients with NPDR after cataract surgery,” the study authors wrote. “Although there is no established standard for dilated fundus examination after uncomplicated cataract surgery in the general population … postoperative dilated fundoscopy is more strongly advocated for in patients with diabetic retinopathy.”
The other study found a modest increase in the risk of nonarteritic anterior ischemic optic neuropathy (NAION) among semaglutide users. The multicenter study used 14 databases comprising 37.1 million adults with type 2 diabetes, including 810,390 new semaglutide users. Adults with diabetes were taking semaglutide, other glucagon-like peptide-1 (GLP-1) receptor agonists (dulaglutide, exenatide), or non-GLP-1 medications (empagliflozin, sitagliptin, glipizide) from December 2017 to December 2023. Results were published Feb. 20 in JAMA Ophthalmology.
The incidence rate of NAION was 14.5 per 100,000 person-years among semaglutide users. When a sensitive definition of NAION was used, the rate was not significantly higher among new users of semaglutide compared with those taking non-GLP-1 drugs, including empagliflozin (hazard ratio [HR], 1.44 [95% CI, 0.78 to 2.68]; P=0.12), sitagliptin (HR, 1.30 [95% CI, 0.56 to 3.01]; P=0.27), and glipizide (HR, 1.23 [95% CI, 0.66 to 2.28]; P=0.25). When a specific definition was used, the risk with semaglutide was higher only compared with empagliflozin (HR, 2.27 [95% CI, 1.16 to 4.46]; P=0.02). However, a self-controlled case-series analysis of semaglutide exposure showed an increased risk of NAION (meta-analysis incidence rate ratio, 1.32 [95% CI, 1.14 to 1.54]; P<0.001).
“Additional studies that incorporate ophthalmic risk factors or examine dose-dependent effects, eg, are needed to investigate a potential causal relationship between semaglutide and NAION,” the authors wrote. “In the absence of a known mechanism for this association, we urge clinicians to weigh the concern for an increased risk of a rare but potentially blinding eye condition with the many therapeutic benefits of semaglutide.”
An accompanying editorial recommended that “patients taking semaglutide should be made aware of the apparent risk of NAION, the magnitude of that risk, and the existence of studies that do not consistently identify an increased risk” and that clinicians “advise added caution for patients taking semaglutide or those who are considering starting this medication if they have experienced visual loss from any cause.”