NCT07458516

Longitudinal Observational Study of Diabetic Retinopathy Progression in Type 2 Diabetes Patients

IMaging Pre-PrOlifeRative sTAge of Diabetic retiNopaThy to Guarantee Timely Treatment - IMPORTANT

• Status: Recruiting
• Phase: —
• Study type: Observational
• Enrollment: 100 (estimated)
• Sponsor: Association for Innovation and Biomedical Research on Light and Image · Academic / Other
• Sex: All
• Age: 35 Years – 80 Years
• Healthy volunteers: Not accepted

Summary

The purpose of this clinical study is to explore imaging, functional and systemic biomarkers of diabetic retinopathy (DR) progression, in Type 2 Diabetes (T2D) patients with moderate to severe non-proliferative diabetic retinopathy (NPDR) and mild proliferative diabetic retinopathy (PDR) using state of the art methodologies, commonly applied in clinical practice, over a period of two years. This study will provide longitudinal data to better understand retinal changes in moderate to severe diabetic retinopathy and early proliferative diabetic retinopathy and help guide timely interventions to prevent vision loss.

Detailed description

Diabetes Mellitus (DM) is an important public health problem, affecting about 589 million people in the world, and expected to reach 853 million by 2050. Active screening for DR is important because most patients may be asymptomatic until the very late stages. Nonproliferative diabetic retinopathy (NPDR) itself may be associated with reduced visual function and quality of life measures (Willis et al., 2017). The molecular pathophysiology of DR is complex, and a complete model of the disease is still being elucidated. The oxidative stress in diabetes upregulates multiple cytokines and chemokines, such as vascular endothelial growth factor (VEGF), angiopoietins, tumour necrosis factor (TNF), interleukins (ILs) and matrix metalloproteinases (MMPs) that leads to breakdown of the blood-retinal-barrier (BRB). Also, retinal capillary obstruction (leukostasis) or dropout (apoptosis of vascular cells) in diabetes leads to tissue ischemia and hypoxia causing increased retinal VEGF expression through transcriptional regulation by hypoxia-inducible factor 1 alpha (HIF-1α) (Arjamaa \& Nikinmaa, 2006; Whitehead et al., 2019). The risk of developing DR complications increases over time, with increasing areas of capillary nonperfusion underpinning progression to more severe forms and development of complications as PDR or diabetic macular edema (DME), driven by hypoxia and hyperexpression of proangiogenic growth factors. However, this risk varies widely, independently of metabolic control. Differentiating patients with higher risk of progression and development of vision-threatening complications (VTC; DME and PDR) is of paramount importance for efficient treatment of the disease in order to prevent vision disability and achieve better visual outcomes. Recent developments in terms of retina imageology, namely Optical Coherence Tomography (OCT) and OCT Angiography (OCTA), have improved the understanding of DR pathophysiology and evolution, with a better characterization of venous abnormalities including occlusion, tortuosity, dilatation, looping or beading. OCTA examination is faster and safer compared to examination with fluorescein angiography (FA), and it can visualise the retinal vasculature in any layer of the retina. OCTA has the potential to become the examination of choice to identify eyes at risk of progression and development of VTC. The purpose of this observational, non-interventional, prospective, and longitudinal clinical study is to explore imaging, functional and systemic biomarkers of DR progression, in T2D patients with moderate to severe NPDR and mild PDR - Diabetic Retinopathy Severity Scale (DRSS) levels 43, 47, 53, and 61 - using state of the art methodologies, commonly applied in clinical practice. Follow-up visits will be performed every 6 months for 2 years with a total of 5 visits. Participants will undergo the following assessments: multimodal retinal imaging, including OCT, OCTA, ultra-widefield (UWF) fundus fluorescein angiography (FFA) and fundus photography (FP), and color fundus photography (CFP); functional testing: best corrected visual acuity (BCVA) and microperimetry (Macular Integrity Assessment, MAIA); collection of systemic health variables, including glycated hemoglobin (HbA1c), blood pressure, diabetes duration, and relevant comorbidities.

Conditions

• Diabetic Retinopathy
• Diabetes Mellitus, Type 2
• Diabetic Complication
• Retinal Disease

Timeline

• Start date: 2025-11-24
• Primary completion: 2027-12-01
• Completion: 2028-06-01
• First posted: 2026-03-09
• Last updated: 2026-03-11

Locations

1 site across 1 country: Portugal