A recently published cohort study in JAMA Ophthalmology, showed that the use of glucagon-like peptide-1 receptor agonists (GLP-1 RAs) among patients with diabetes was associated with a two-fold higher risk of incident neovascular age-related macular degeneration (nAMD) development than among similar patients with diabetes who did not receive a GLP-1 RA. 

GLP-1 RAs are extensively used in treating diabetes and obesity, yet little is known about the long-term ocular effects of systemic prolonged exposure, hence the objective of this study was to evaluate the risk of developing nAMD associated with the use of GLP-1 RAs in patients with diabetes.

The study was conducted from January 2020 to November 2023, with a follow-up period of three years. 

The investigators used comprehensive administrative health and demographic data from patients in Ontario, Canada. Inclusion criteria were patients aged 66 years or older with a diagnosis of diabetes and a minimum follow-up period of 12 months following initial diabetes diagnosis. Patients exposed to GLP-1 RA for less than six months were excluded.

Of a total of 1,119,517 eligible patients, a 1:2 matched cohort of 139,002 patients was created, including 46,334 patients who were exposed to GLP-1 RAs and 92,668 unexposed matched patients. Systemic comorbidities that were associated with any kind of AMD and socioeconomic status were used to calculate propensity scores.

Among 139,002 matched patients, mean (SD) patient age was 66.2 (7.5) years, and 64,775 patients (46.6%) were female. The incidence of nAMD was higher among the exposed cohort than among the unexposed cohort. Estimated hazard ratios for nAMD development were greater than 2.0 among patients exposed to GLP-1 RAs.

Further research is needed to elucidate the exact pathophysiological mechanisms involved and to understand the trade-offs between the benefits and risks of GLP-1 RAs.