Abstract

1. 3720 - Risk Factors for Intraocular Ischemia and Neovascularization in Central Retinal Vein Occlusion (CRVO) in Diabetic Versus Nondiabetic PatientsJ.G. Santiago1, J.K. Sun1,2, P.S. Silva1, Z.A. Haddad1, and L.P. Aiello1,21Beetham Eye Institute, Joslin Diabetes Center, Boston, MA; 2Ophthalmology, Harvard Medical School, Boston, MA Results Background Abstract 104 eyes of 99 patients with CRVO were evaluated. Baseline patient characteristics are shown in Table 1 and Table 2. Table 1: Baseline characteristics in DM vs. Non-DM patients Table 2: Baseline characteristics in Type 1 vs. Type 2 DM patients The prevalence of systemic hypertension, use of antihypertensive medications, CVD, hyperlipidemia and hyperlipidemic treatment were significantly more common in diabetic patients compared to non-DM patients (Figure 1). Systolic and diastolic blood pressure were not significantly different in DM patients (mean BP: 136/75) compared to non-DM patients (mean BP: 131/78). Ischemic CRVO tended to be more common in DM than non-DM eyes (13.9 vs. 5.6%) and subjects with DM tended to develop more frequent neovascularization of all sorts. These differences were statistically significant for NVD (21.3 vs. 0.0%, p=0.05) (Figure 2). None of the patients with optic nerve head collateral vessels (CVs) at baseline had ischemic CRVO whereas 12.5% of patients without CVs had ischemic CRVO (p=0.36). Non-DM eyes with CRVO (59.1%) tended to develop more CVs than DM eyes (48.1%, p=0.39). Central retinal vein occlusion (CRVO) is a common retinal vascular disease and may be associated with significant visual loss. Visual loss commonly results from macular edema, neovascular complications and other adverse effects of the associated intraocular ischemia. Multiple risk factors have been associated with development of CRVO including diabetes mellitus (DM), history of cardiovascular disease (CVD), systemic hypertension and primary glaucoma. Co-existing DM is reported in 15-20% of patients with CRVO and may significantly affect the natural history in this subgroup of patients.2 CRVO eyes with type 1 DM were nine times more likely to have retinal neovascularization (28.6 vs. 3.2%, p=0.004) at endpoint, and less than half past likely to develop CVs (21.4 vs. 56.5%, p=0.04) than those with type 2 DM (Figure 3). There is a known relationship between POAG and CRVO and glaucoma medications were more common in non-DM patients. Non-DM subjects with CRVO were more likely to be using glaucoma medications prior to CRVO diagnosis (Figure 4) and to have a lower mean IOP than diabetic subjects who developed CRVO (Figure 5). Panretinal photocoagulation (PRP) after a CRVO was more common in DM eyes (48.7%) than non-DM eyes (21.4%, p=0.01) (Figure 6). By comparison, only 14.7% of the non-CRVO DM eyes required PRP during this period. CRVO patients with type 1 DM were more likely to undergo subsequent PRP compared to subjects with type 2 DM (78.6% vs. 41.9%, p=0.01). Furthermore, the presence of CVs at baseline was associated with decreased rates of PRP (14.3 vs. 46.1%, p=0.03) (Figure 7). Purpose Summary • To identify risk factors associated with intraocular ischemia and neovascularization among CRVO patients with DM compared to those without DM (non-DM). • In this cohort of 104 eyes with CRVO in 99 subjects: • 14% of DM eyes with CRVO developed ischemic CRVO as compared with 6% of non-DM eyes. • Ocular neovascularization occurred in 49% of DM eyes but only 29% of non-DM eyes. • Non-DM patients were more likely to be using glaucoma medications prior to CRVO than DM patients. • 49% of DM eyes required PRP treatment as compared to 21% of non-DM eyes. • 79% of T1DM eyes required PRP as compared to 42% of T2DM eyes. • Retinal neovascularization was 9X more likely in T1DM eyes while collateral disc vessels formation was 2X more frequent in T2DM. Methods A retrospective medical record review of all patients seen at the Beetham Eye Institute (BEI) of the Joslin Diabetes Center, Harvard Medical School from January 1, 2004 to November 15, 2008 was performed. A structured electronic search query from the EMR was used to identify all CRVO patients. The individual medical records of all identified patients were retrieved and all pertinent information was recorded in a standardized form. The diagnosis of CRVO and DM was confirmed based on the systemic findings and clinical characteristics documented at the initial BEI visit. Baseline demographics and pertinent systemic medical risk factors that have been reported to affect the progression of diabetic retinopathy or increase the risk for development of CRVO were noted. The ophthalmic findings from all patients at the initial visit (visit 1), 4 months (visit 2; window = 3-6 months) and last follow up visit (visit 3) were recorded. Data from the visit prior to development of CRVO were also recorded when available as were the dates of all ophthalmic procedures performed after the development of the CRVO. All analyses were performed using Statistical Analyses System software V9.2 (SAS Institute, North Carolina). Nonparametric analyses (Wilcoxon rank sums) were used to compare distributions of continuous variables between groups. The Chi square test was used to compare frequencies of categorical variables. Conclusions • Patients with DM are more likely to develop ischemic CRVO and ocular neovascularization and more likely to require PRP after CRVO than are patients without DM • Collateral disc vessels formation at baseline is a good prognostic factor being associated with reduced retinal ischemia and less subsequent need for laser treatment after CRVO. • Patients with Type 1 DM are less likely to develop collateral disc vessels after CRVO and much more prone to develop neovascularization after CRVO than are those with Type 2 DM. • Glaucoma may be more strongly associated with CRVO in non-DM patients than in DM patients. References The Eye Disease Case-Control Study Group. Risk Factors for Central Retinal Vein Occlusion. Arch Ophthalmol. 1996;114:545-554 Mansour AM, et al: Role of Diabetes Mellitus on the Natural History of Central Retinal Vein Occlusion. Ophthalmologica 1992;204:57-62 Funderburk RL and Feinberg EB: Diabetes as a Risk Factor for Retinal Neovascularization in Retinal Vein Occlusion. Ann Ophthalmol. 1989;21:65-66 ***Authors Disclosure Information: None***