Julia Hafner1, Markus Zadrazil2, Anna Grisold3, Gerda Ricken4, Martin Krenn3, Daniela Kitzmantl4, Andreas Pollreisz1, Andreas Gleiss5, Ursula Schmidt-Erfurth6. 1. Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, Austria. 2. Department of Anesthesiology, General Intensive Care and Pain Control, Medical University of Vienna, Vienna, Austria. 3. Department of Neurology, Medical University of Vienna, Vienna, Austria. 4. Institute of Neurology, Medical University of Vienna, Vienna, Austria. 5. Center for Medical Statistics, Informatics and Intelligent Systems, Medical University of Vienna, Vienna, Austria. 6. Department of Ophthalmology and Optometry, Medical University of Vienna, Vienna, Austria. Electronic address: ursula.schmidt-erfurth@meduniwien.ac.at.
Abstract
PURPOSE: To determine the extent of retinal and corneal neurodegeneration and investigate the association with intraepidermal neuronal loss and diabetic peripheral neuropathy (DPN) in type 2 diabetes. DESIGN: Prospective, cross-sectional study. METHODS: Single-center study of 94 patients with type 2 diabetes patients (157 eyes), divided into groups: the groups without diabetic retinopathy (DR) (n = 68); the nonproliferative DR (NPDR) group (n = 48); and the proliferative DR (PDR) group (n = 41). Patients were imaged with optical coherence tomography and confocal microscopy for macular and peripapillary neuroretinal layer thicknesses and corneal nerve length/density, respectively. Distal leg skin punch biopsies and 2 neurological scores were used to depict intraepidermal nerve fiber density (IENFD) and clinical DPN. RESULTS: Among neuroretinal layers, solely the peripapillary retinal nerve fiber layer was decreased in PDR (96 μm; 95% confidence interval [CI], 92-100 μm) versus no DR (103 μm; 95% CI, 100-106 μm) eyes and only after exclusion of outliers (P = .01). Corneal nerve fiber length and density were statistically significantly reduced in the NPDR group (23.0 mm/mm2; 95% CI, 20.0-26.00 mm/mm2 and 14.3 mm; 95% CI, 14.5-16.63 mm, respectively) and the PDR group (18.6 mm/mm2; 95% CI, 14.9-22.30 mm/mm2 and 11.7 mm; 95% CI, 10.2-13-3 mm, respectively) versus the no DR group (25.5 mm/mm2; 95% CI, 23.3-27.70 mm/mm2 and 15.6 mm; 95% CI, 14.5-16.6 mm, respectively), and in the PDR versus the NPDR group. IENFD was statistically significantly reduced in the NPDR (2.0/mm; 95% CI, 1.4-2.7/mm) and PDR stage (1.4/mm; 95% CI, 0.9-2.1/mm) versus in eyes without DR (3.6/mm; 95% CI, 2.9-4.6/mm). A low correlation between intraepidermal and corneal fiber loss was found with both neurological scores (P < .05). CONCLUSIONS: Retinal neurodegenerative changes may develop independently of the microvascular alterations defining DR. Corneal and intraepidermal neuronal loss is more pronounced in advanced stages of DR, indicating a positive severity correlation between DR and DPN.
PURPOSE: To determine the extent of retinal and corneal neurodegeneration and investigate the association with intraepidermal neuronal loss and diabetic peripheral neuropathy (DPN) in type 2 diabetes. DESIGN: Prospective, cross-sectional study. METHODS: Single-center study of 94 patients with type 2 diabetespatients (157 eyes), divided into groups: the groups without diabetic retinopathy (DR) (n = 68); the nonproliferative DR (NPDR) group (n = 48); and the proliferative DR (PDR) group (n = 41). Patients were imaged with optical coherence tomography and confocal microscopy for macular and peripapillary neuroretinal layer thicknesses and corneal nerve length/density, respectively. Distal leg skin punch biopsies and 2 neurological scores were used to depict intraepidermal nerve fiber density (IENFD) and clinical DPN. RESULTS: Among neuroretinal layers, solely the peripapillary retinal nerve fiber layer was decreased in PDR (96 μm; 95% confidence interval [CI], 92-100 μm) versus no DR (103 μm; 95% CI, 100-106 μm) eyes and only after exclusion of outliers (P = .01). Corneal nerve fiber length and density were statistically significantly reduced in the NPDR group (23.0 mm/mm2; 95% CI, 20.0-26.00 mm/mm2 and 14.3 mm; 95% CI, 14.5-16.63 mm, respectively) and the PDR group (18.6 mm/mm2; 95% CI, 14.9-22.30 mm/mm2 and 11.7 mm; 95% CI, 10.2-13-3 mm, respectively) versus the no DR group (25.5 mm/mm2; 95% CI, 23.3-27.70 mm/mm2 and 15.6 mm; 95% CI, 14.5-16.6 mm, respectively), and in the PDR versus the NPDR group. IENFD was statistically significantly reduced in the NPDR (2.0/mm; 95% CI, 1.4-2.7/mm) and PDR stage (1.4/mm; 95% CI, 0.9-2.1/mm) versus in eyes without DR (3.6/mm; 95% CI, 2.9-4.6/mm). A low correlation between intraepidermal and corneal fiber loss was found with both neurological scores (P < .05). CONCLUSIONS:Retinal neurodegenerative changes may develop independently of the microvascular alterations defining DR. Corneal and intraepidermal neuronal loss is more pronounced in advanced stages of DR, indicating a positive severity correlation between DR and DPN.
Authors: Rohith N Thota; Pratishtha Chatterjee; Steve Pedrini; Eugene Hone; Jessica J A Ferguson; Manohar L Garg; Ralph N Martins Journal: Front Endocrinol (Lausanne) Date: 2022-06-20 Impact factor: 6.055