PURPOSE: To determine the association between hemorrhages and/or microaneurysm (HMa) counts and distribution, as identified using ultrawide field imaging (UWFI), and risk of diabetic retinopathy (DR) progression over 4 years.
METHODS: Single-site prospective 4-year longitudinal study. Eyes with mild to moderate nonproliferative DR (NPDR) on ETDRS photos were evaluated. ETDRS photos and UWFI were acquired using standardized protocols at the same visit. Baseline HMa counts in ETDRS fields and in UWFI areas not covered by ETDRS photos were obtained. A ratio of HMa counts outside to HMa counts within the ETDRS fields was calculated. A ratio >1.0 was termed a predominantly peripheral HMa distribution (PPL-HMa), ≤1.0 termed posterior distribution (Post-HMa). Based on ETDRS definitions of severe H/Ma (≥20 per field), severe HMa on UWFI was considered ≥80 overall. Follow-up ETDRS photos were acquired at 4 years.
RESULTS: 102 eyes were evaluated [48 (47%) mild, 54 (53%) moderate NPDR]. Follow-up 4-year ETDRS photos were acquired in 38 (79.2%) eyes with mild and 44 (81.5%) eyes with moderate NPDR. In mild NPDR, 12 (31.6%) had PPL-HMa and 26 (68.4%) Post-HMa. DR severity progressed ≥2-step (≥2-step-prog) in 16.7% with PPL-HMa (2 of these eyes developed PDR, H/Ma ratio 3.45 & 2.73) and 0% with Post-HMa (p=0.033). In moderate NPDR, 5 (11.4%) had PPL-H/Ma and 39 (88.6%) Post-HMa. ≥2-step-prog with PPL-HMa was 20% vs 23% with Post-HMa (p=NS). In mild NPDR, 8 (21.0%) had HMa count ≥80 and 30 (79.0%) had <80. ≥2-step-prog was 100% in eyes with ≥80 compared to 0% when <80. (p=0.005). In moderate NPDR, 23 (52.3%) had HMa count ≥80 and 21 (47.7%) had <80 with ≥2-step-prog of 43.5% in ≥80 and 0% in <80 (p=0.006). In mild to moderate NPDR, an increase of 10 HMa on UWFI increased the risk for 2-step-prog (OR: 1.23, 95% CI 1.09-1.46, p=0.002), a finding that remained significant after correcting for baseline DR severity (p=0.006).
CONCLUSIONS: In mild to moderate NPDR at baseline, more peripheral HMa and more total HMa are associated with increased progression over 4 years. For every 10 HMa identified on UWFI, the risk for DR progression over 4 yrs may be increased 23%. The larger retina area imaged and the greater number of HMa seen on UWF may provide a better overall assessment of DR activity and risk of progression.
