<?xml version="1.0" encoding="UTF-8"?><OAI-PMH xmlns="http://www.openarchives.org/OAI/2.0/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd"><responseDate>2026-10-21T05:17:19Z</responseDate><request verb="GetRecord" identifier="oai:ebyu-rdlopen.rawdatalibrary.net:ebyu/27596" metadataPrefix="oai_dc">https://ebyu-rdlopen.rawdatalibrary.net/oai/request</request><GetRecord><record><header><identifier>oai:ebyu-rdlopen.rawdatalibrary.net:ebyu/27596</identifier><datestamp>2026-10-20T22:46:02Z</datestamp><setSpec>openaire</setSpec><setSpec>driver</setSpec><setSpec>com_ebyu_10007</setSpec><setSpec>col_ebyu_25981</setSpec><setSpec>com_ebyu_10006</setSpec><setSpec>col_ebyu_25956</setSpec></header><metadata><oai_dc:dc xmlns:oai_dc="http://www.openarchives.org/OAI/2.0/oai_dc/" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.openarchives.org/OAI/2.0/oai_dc/ http://www.openarchives.org/OAI/2.0/oai_dc.xsd"><dc:title xml:lang="tr">Diyabetik retinopatide optik koherens tomografi anjiyografi bulgularının metabolomik profil, nefropati ve kardiyovasküler hastalık riski ile korelasyonunun değerlendirilmesi</dc:title><dc:title xml:lang="en">Assessment of the association of optical coherence tomography angiography findings in diabetic retinopathy with metabolomic profile, nephropathy, and cardiovascular disease risk</dc:title><dc:creator>Samet Aldağ</dc:creator><dc:contributor>Prof. Dr. Yücel Karakurt</dc:contributor><dc:description xml:lang="tr">Amaç: Diyabet spektrumunun farklı evrelerinde OCTA ile ölçülen retinal mikrovasküler parametrelerin diyabetik nefropati belirteçleri ve UKPDS temelli kardiyovasküler risk skorları ile ilişkisini bütüncül olarak değerlendirmek ve retina–böbrek–kalp eksenindeki ortak patofizyolojik yükü tanımlamaktır. Gereç ve Yöntem: Prospektif-kesitsel çalışmaya ADA kriterlerine göre kontrol (n=37), prediyabet (n=31), DR olmayan tip 2 DM (n=48), hafif–orta NPDR (n=20) ve şiddetli NPDR (n=24) olmak üzere toplam 160 olgu dahil edildi. ETDRS'ye göre evreleme sonrası OCT/OCTA ile FAZ metrikleri, SCP/DCP ve peripapiller RPC damar yoğunlukları ile retinal kalınlıklar ölçüldü. Nefropati eGFR (CKD-EPI), mikroalbüminüri ve ACR ile; kardiyovasküler risk UKPDS Risk Engine ile değerlendirildi. Plazma örneklerinde hedef dışı LC–MS tabanlı metabolomik analiz yapıldı; PCA ve yolak analizleri uygulandı. Bulgular: Retinopati şiddeti arttıkça FAZ alanı/perimetresi arttı, dairesellik azaldı (p&lt;0,001). SCP/DCP ve RPC damar yoğunlukları NPDR evreleriyle progresif azaldı (p&lt;0,001); şiddetli NPDR'de makula kalınlıkları daha yüksekti (p&lt;0,01). Mikroalbüminüri ve ACR NPDR gruplarında arttı, eGFR azaldı (p&lt;0,001). UKPDS'ye göre koroner hastalık ve inme riskleri diyabet ve NPDR gruplarında daha yüksekti (p&lt;0,001). PCA'da gruplar arasında kademeli ayrışma izlendi (PC1 %40,8; PC2 %17,4) ve enerji metabolizması, lipid peroksidasyonu, inflamasyon ve oksidatif stresle ilişkili yolaklarda progresyonla uyumlu değişimler saptandı. Sonuç: DR/NPDR şiddet artışı, OCTA ile mikrovasküler bozulma, nefropati göstergelerinde kötüleşme ve artmış UKPDS kardiyovasküler risk ile birlikte seyretmektedir. Metabolomik bulgular, progresyonla uyumlu enerji metabolizması ve oksidatif stres/inflamasyon ekseninde belirgin değişimleri desteklemektedir. Retinal OCTA parametreleri sistemik mikrovasküler yükün noninvaziv göstergeleri olabilir.</dc:description><dc:description xml:lang="en">Background: To comprehensively evaluate the associations between retinal microvascular parameters measured by OCTA across different stages of the diabetes spectrum and markers of diabetic nephropathy as well as UKPDS-based cardiovascular risk scores, and to characterize the shared pathophysiological burden along the retina–kidney–heart axis. Methods: In this prospective cross-sectional study, a total of 160 participants were enrolled according to ADA criteria and stratified into five groups: controls (n=37), prediabetes (n=31), type 2 diabetes mellitus without diabetic retinopathy (n=48), mild–moderate NPDR (n=20), and severe NPDR (n=24). Following ETDRS-based staging, OCT/OCTA was performed to quantify FAZ metrics, superficial and deep capillary plexus (SCP/DCP) and peripapillary radial peripapillary capillary (RPC) vessel densities, and retinal thickness parameters. Diabetic nephropathy was assessed using eGFR (CKD-EPI), microalbuminuria, and the albumin-to-creatinine ratio (ACR), while cardiovascular risk was estimated with the UKPDS Risk Engine. Untargeted LC–MS-based metabolomic profiling was conducted on plasma samples, and multivariate analyses (PCA) and pathway enrichment analyses were applied. Results: With increasing retinopathy severity, FAZ area and perimeter increased whereas FAZ circularity decreased (p&lt;0.001). SCP/DCP and RPC vessel densities progressively declined across NPDR stages (p&lt;0.001); macular thickness parameters were higher in the severe NPDR group (p&lt;0.01). Microalbuminuria and ACR increased in the NPDR groups, while eGFR decreased (p&lt;0.001). According to UKPDS, coronary heart disease and stroke risk scores were higher in the diabetes and NPDR groups than in the control/prediabetes groups (p&lt;0.001). PCA demonstrated a stepwise separation between groups (PC1 40.8%; PC2 17.4%), with progression-consistent alterations in pathways related to energy metabolism, lipid peroxidation, inflammation, and oxidative stress. Conclusion: Increasing DR/NPDR severity is accompanied by OCTA-derived retinal microvascular impairment, worsening nephropathy markers, and elevated UKPDS cardiovascular risk. Metabolomic findings support pronounced progression-related changes in energy metabolism and oxidative stress/inflammation axes. These results suggest that retinal OCTA parameters may serve as noninvasive indicators of systemic microvascular burden.</dc:description><dc:publisher>Erzincan Binali Yıldırım University</dc:publisher><dc:date>2025</dc:date><dc:type>Thesis</dc:type><dc:identifier>https://rdlopen.rawdatalibrary.net/r/ebyu/27596</dc:identifier><dc:language>tr</dc:language><dc:rights>info:eu-repo/semantics/openAccess</dc:rights><dc:type>info:eu-repo/semantics/bachelorThesis</dc:type><dc:identifier>https://ebyu-rdlopen.rawdatalibrary.net/tr/items/ebyu/27596</dc:identifier></oai_dc:dc></metadata></record></GetRecord></OAI-PMH>