Abstract
Purpose :
Geographic atrophy (GA) is an advanced stage of age-related macular degeneration (AMD) that causes substantial visual disability. With the emergence of complement inhibition therapy to slow GA progression, early identification of atrophic lesions may lead to earlier intervention and delay of visual impairment from foveal involving atrophy. This study aimed to identify the prevalence of GA lesions in patients with an intermediate AMD (iAMD) ICD-10 code diagnosis as guided by optical coherence tomography (OCT), and compare them to individuals with an established ICD-10 code diagnosis of GA.
Methods :
A retrospective cohort study was conducted. 160 eyes from 94 patients with iAMD were included. Patients diagnosed with other maculopathies were excluded. 5 mm sub-RPE illumination (SRI) area corresponding to the GA lesion area, the shortest distance of atrophy from fovea, and central subfield thickness (CST) were calculated using Zeiss (Jena, Germany) OCT software. A SRI area ≥ 0.4 mm2 defined the presence of GA. Propensity score matching was used to identify age and sex matched controls with an ICD-10 code diagnosis of GA. Multiple logistic regression was used to assess risk factors for iAMD patients with and without GA and those with an ICD-10 code diagnosis of GA.
Results :
In the iAMD group, 28.7% were male and 90.4% were white, with a mean age of 83.0±6.88 years. GA lesions were identified in 48 eyes (30%) of 34 patients (36%). Mean visual acuity (VA) was significantly higher in patients without lesions compared to those with lesions (72.1±11.7 vs 65.6±17.1 letters, p=0.03). Propensity-matched analysis revealed smaller SRI area (2.17 vs 4.40 mm2, p=0.0007), larger distance to fovea (0.43 vs 0.15mm, p=0.0007), and better VA (65.8±17.7 vs 56.3±24.1 letters, p=0.01) in iAMD patients with GA lesions versus patients with diagnosed GA. iAMD patients with lesions were more likely to have diabetes than patients with diagnosed GA (OR=25.6, p=0.003). Increased age, hypertension, dyslipidemia, coronary artery disease, or BMI were not associated with an increased risk of GA lesions when comparing to the iAMD group without the lesions.
Conclusions :
One third of eyes with an ICD-10 diagnosis of iAMD had evidence of GA lesions on OCT. Use of OCT software-calculated SRI area as a screening tool may aid in the early detection of GA in patients with iAMD.
This abstract was presented at the 2023 ARVO Annual Meeting, held in New Orleans, LA, April 23-27, 2023.