5-Year Outcomes of Anti-VEGF Treatment in AMD
Maguire et al., writing on behalf of the Comparison of Age-Related Macular Degeneration Treatments Trials (CATT) Research Group, describe the 5-year outcomes of patients treated with bevacizumab or ranibizumab for neovascular age-related macular degeneration (AMD). Although the vision gains seen in the first 2 years of CATT were not maintained, half of the patients still had visual acuity of 20/40 or better.
In the original CATT cohort study, participants were randomly assigned to ranibizumab or bevacizumab at 1 of 3 dosing regimens. After 2 years, participants were released from their clinical trial protocol; at 5 years, they were recalled for an examination. The main outcome measures were visual acuity (VA) and morphologic retinal features.
The researchers determined VA for 647 of 914 surviving patients, at an average follow-up of 5.5 years. The mean number of examinations for AMD care after the clinical trial ended was 25.3, and the mean number of treatments was 15.4. Most patients (60%) were treated 1 or more times with a drug other than that originally assigned. At the 5-year visit, 50% of eyes had a VA of 20/40 or better, and 20% had a VA of 20/200 or worse. The mean change in VA was –3 letters from baseline and –11 letters from the 2-year level.
Among the 467 eyes that underwent fluorescein angiography, the mean total lesion area was 12.9 mm2, representing a mean increase of 4.8 mm2 from that at 2 years. Geographic atrophy was present in 213 of 515 (41%) gradable eyes and was subfoveal in 85 eyes (17%).
Among 555 eyes examined with spectral-domain optical coherence tomography, 83% had fluid (intraretinal, subretinal, or sub–retinal pigment epithelium). The mean foveal thickness was 278 μm, representing a decrease of 182 μm from baseline and 20 μm from 2 years. The retina was abnormally thin (<120 μm) in 36% of eyes. Between 2 and 5 years, the group originally assigned to ranibizumab for 2 years lost more VA than did those in the bevacizumab group (–4 letters; p = .008). Otherwise, no statistically significant differences in VA or in morphologic outcomes were noted between the drug or regimen groups.
The authors commented that before the introduction of anti-VEGF therapy for AMD, less than 10% of patients retained vision of ≥20/40 without treatment, and less than 15% of patients treated with photodynamic therapy retained that level of vision, at 2 years after diagnosis. Thus, the fact that 50% of the CATT eyes had ≥20/40 VA at 5 years confirms that anti-VEGF is a major long-term therapeutic advance for patients with neovascular AMD.
Acanthamoeba Keratitis Among RGP Contact Lens Wearers
Cope et al. described the presentation and outcomes of Acanthamoeba keratitis (AK) in rigid gas permeable (RGP) contact lens wearers. The researchers also identified potential modifiable risk factors that may improve or eliminate the risk of associated vision loss.
This case-control study included 37 cases, patients who had used RGP contact lenses and had been diagnosed with AK between 2005 and 2011. The controls were 17 individuals who wore RGP contact lenses but had no history of AK. Nine of the cases (24%) wore RGP lenses for orthokeratology or for a therapeutic indication; no controls wore RGP lenses for these reasons. Participants were interviewed by phone using a standardized questionnaire. Odds ratios (ORs) and Fisher exact p values were calculated to assess risk factors associated with infection.
The researchers found that significant risk factors included wearing lenses for orthokeratology (OR, undefined; p = .02), wearing lenses while sleeping (OR, 8.00; p = .04), storing lenses in tap water (OR, 16.00; p = .001), and topping off lens solution in the case instead of emptying it and filling with fresh solution (OR, 4.80; p = 0.01). After stratification by lens use for orthokeratology, storing lenses in tap water and topping off solution remained significant risks.
The authors concluded that all of the significant risk factors are modifiable; thus, increased efforts must be made to educate patients on the hazards of storing RGP lenses in tap water or topping off the solution. These cautions are particularly important for orthokeratology patients, whose overnight lens wear puts greater metabolic stress on the cornea.
African Descent and Glaucoma Evaluation Study (ADAGES)
Skaat et al. investigated differences in the frequency of optic disc hemorrhage (DH) and the prevalence of beta-zone parapapillary atrophy (ßPPA) among individuals of African descent (AD) and European descent (ED). They found that people of AD have a higher prevalence of ßPPA, while those of ED have a higher risk of DH; both of these features are associated with glaucomatous optic neuropathy (GON).
Researchers in this prospective multicenter observational cohort study examined stereoscopic disc photographs of 1,950 eyes of 1,172 participants in the African Descent and Glaucoma Evaluation Study (ADAGES). This included 928 eyes (347 with GON; 581 non-GON) of 551 AD patients, and 1,022 eyes (454 with GON; 568 non-GON) of ED patients. During the first 13 years of the study, the investigators reviewed 9,395 photos. The masked review of images searched for DH and ßPPA. The study’s main outcome measures were differences in the frequency of DH and in the prevalence of ßPPA in the AD and ED groups.
More ED eyes had DH than did AD eyes (49/1,022 [4.8%] versus 10/928 [1.1%]), respectively; p < .001). In contrast, there was a higher prevalence of ßPPA in AD eyes than in ED eyes (675 [72%] versus 659 [64%], respectively; p < .001).
According to the researchers, these findings suggest structural differences within the optic nerve complex between people of African descent and European descent. They added that further research is needed to elucidate whether these differences affect the likelihood of glaucomatous progression.
Ophthalmology summaries are written by Marianne Doran and edited by Susan M. MacDonald, MD.
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American Journal of Ophthalmology