As geographic atrophy (GA) commonly occurs in elderly patients who often require multiple medications for other comorbidities, researchers looked into a potential association between the two. The study, published in Retina, found that most systemic meds don’t cause GA in AMD patients. The only exception was calcium channel blockers, which were significantly associated with a faster growth rate of GA.
The study randomized participants with new, untreated choroidal neovascularization in the study eye into bevacizumab or ranibizumab treatment groups. Individuals were released from clinical trial treatment at two years and examined at approximately five years. Two masked graders assessed the presence and size of GA from color fundus images and fluorescein angiograms taken at baseline and years one, two and five. The researchers also interviewed participants about systemic medication use at baseline.
Based on multivariable analysis of 1,011 study eyes without baseline GA, the investigators found no link between development of the condition and the use of several systemic medications, including cholinesterase and ACE inhibitors, calcium channel blockers, beta-blockers, diuretics, aspirin, steroids, statins, HRT, antacids and drugs targeting G protein-coupled receptors.
In a group of 214 study eyes with longitudinal GA size measurements, however, calcium channel blockers were linked to a faster GA growth rate (0.40mm per year vs. 0.30mm per year).
This finding has not been previously reported, but caution must be taken in interpreting this result, as it may be caused by chance or be attributed to uncontrolled confounding variables and should be validated in future studies, the study authors concluded.
Song D, Hua P, VanderBeek BL, et al. Systemic medication use and the incidence and growth of geographic atrophy in the comparison of age-related macular degeneration treatments trials (CATT). Retina. December 14, 2020. [Epub ahead of print].