Influence of baseline diabetic retinopathy status on initial anatomical response of intravitreal ranibizumab therapy for diabetic macular oedema

• Published in: Eye (London) 2017-09, Vol.31 (9), p.1358-1364
• Main Authors: Nicholson, L, Patrao, N V, Ramu, J, Vazquez-Alfageme, C, Muwas, M, Rajendram, R, Hykin, P G, Sivaprasad, S
• Format: Article
• Language: English
• Subjects: 692/699/3161/3175; 692/700/565/1436; Aged; Angiogenesis Inhibitors - therapeutic use; Clinical Study; Diabetes; Diabetes mellitus; Diabetic retinopathy; Diabetic Retinopathy - drug therapy; Diabetic Retinopathy - physiopathology; Edema; Female; Fluorescein Angiography; Humans; Immunotherapy; Intravitreal Injections; Laboratory Medicine; Macular Edema - drug therapy; Macular Edema - physiopathology; Male; Medicine; Medicine & Public Health; Middle Aged; Monoclonal antibodies; Ophthalmology; Pharmaceutical Sciences/Technology; Ranibizumab - therapeutic use; Retina; Retina - pathology; Retinopathy; Retrospective Studies; Statistical analysis; Surgery; Surgical Oncology; Tomography, Optical Coherence; Vascular endothelial growth factor; Vascular Endothelial Growth Factor A - antagonists & inhibitors
• ISSN: 0950-222X; 1476-5454
• DOI: 10.1038/eye.2017.69

Purpose Intraocular vascular endothelial growth factor (VEGF) levels increases with the severity of diabetic retinopathy. Response of diabetic macular oedema (DMO) to ranibizumab is driven by VEGF suppression. We hypothesised that the initial reduction of central macular thickness by ranibizumab should be maximum in severe diabetic retinopathy until the levels of VEGF decreases to the levels observed in eyes with mild retinopathy. Methods Consecutive patients with centre-involving DMO (central subfield thickness (CSFT)>300  μ m) who had three consecutive monthly ranibizumab injections followed by as needed therapy were included. Retinopathy status was graded as mild non-proliferative diabetic retinopathy (NPDR) (G1), moderate to severe NPDR with no prior panretinal photocoagulation (G2), and treated PDR (G3). Results Two hundred and thirty-nine eyes from 204 patients with a mean age of 64.9 years were included. The distribution was 31.4 G1, 32.2 G2, and 36.4% G3. Mean baseline CSFT for all eyes was 458.5±110.8  μ m. Baseline CSFT for G1, G2, and G3, respectively, were 437.6±90.9, 472.3±109.8, and 464.7±124.9  μ m ( P =0.2155). Mean change in CSFT after three consecutive injections was 128.5±116.6  μ m. The mean changes were 95.8±101.4  μ m for G1, 137.2±112.9  μ m for G2, and 148.9±126.9  μ m for G3. The changes in CSFT between groups adjusted for baseline CSFT were statistically significant ( P =0.0473). At 6 and 12 months after a mean of 4.5 and 7.7 injections, the changes between groups were no longer significant, P =0.4783 and P =0.8271, respectively. Conclusions The initial anatomical response of DMO with intravitreal ranibizumab injections was maximum in eyes with treated PDR, suggesting that the higher the VEGF levels, the better the response with ranibizumab.