Cataract surgery does not increase risk of AMD progression

SAN FRANCISCO — Cataract surgery does not appear to impact progression of age-related macular degeneration, and observations of more advanced disease after cataract removal may result from an improved diagnostic ability to identify underlying pathology after removal of an opacified lens, a lecturer said here.

At Retina Subspecialty Day preceding the American Academy of Ophthalmology, Susan B. Bressler, MD, said several researchers have proposed different theoretical mechanisms by which cataract removal may increase risk of AMD progression, including increased delivery of potentially toxic blue light, surgically induced inflammation, and the potential for shared risk factors for both pathologic states.

Some large-scale population studies have suggested an association between the two conditions, but Dr. Bressler noted, "I cannot stress this enough: Association does not imply causation."

In a small study performed at the Wilmer Eye Clinic, Dr. Bressler and colleagues noted a low incidence rate of either geographic atrophy or choroidal neovascularization developing between 1 week and 1 year after cataract surgery in 71 prospectively followed patients.

Likewise, Dr. Bressler said, analysis of data from the AREDS study revealed no increased risk on Cox regression analysis, a potentially small increased risk in comparing case (cataract removal) and age-matched controls, but no increased risk on logistic regression.

"There is no clear evidence that AMD eyes are at a clinically important greater risk of progression to advanced AMD following cataract surgery," Dr. Bressler said.