RecruitingNot ApplicableNCT06713720

Remote Ischemic Conditioning for Non-Proliferative Diabetic Retinopathy

Remote Ischemic Conditioning for Non-Proliferative Diabetic Retinopathy (RIC-NPDR)

Sponsor

Xuxiang Zhang, MD

Enrollment

68 participants

Start Date

Apr 20, 2025

Study Type

INTERVENTIONAL

Conditions

Diabetes Mellitus, Type 2 Randomized Controlled Trial Diabetic Retinopathy Non-Proliferative Diabetic Retinopathy Remote Ischemic Conditioning

Summary

The goal of this clinical trial is to evaluate whether remote ischemic conditioning (RIC) is a safe and effective treatment for non-proliferative diabetic retinopathy (NPDR) in adults aged 40-80 years with type 2 diabetes. The study aims to address the limitations of current treatments for NPDR by using RIC, a technique involving repeated cycles of ischemia and hypoxia stimulation to activate protective mechanisms against retinal damage. The main questions it aims to answer are: Does RIC improve the Diabetic Retinopathy Severity Score (DRSS) after one year of treatment? Does RIC reduce the incidence of vision-threatening proliferative diabetic retinopathy (PDR)? What are the changes in retinal neurovascular unit parameters, visual acuity, and retinal oxygen saturation after RIC treatment? Participants will: Undergo RIC therapy using a specialized device on both upper limbs (or a placebo intervention for the control group) for 1 year. Complete 5 cycles of RIC or placebo treatment twice daily, 5 days per week. Receive routine care for diabetic retinopathy as per clinical guidelines. Key outcome measures: Primary outcome: Change in DRSS from baseline after one year. Secondary outcomes: Incidence of PDR, changes in visual acuity, retinal neurovascular unit measures, retinal oxygen saturation, and serum biomarkers (e.g., VEGF, CRP, IL-6). This randomized, double-blind, placebo-controlled trial aims to recruit 68 participants to ensure 60 complete the study, accounting for a 13% dropout rate. The findings are expected to provide insights into RIC as a novel intervention for NPDR, reducing blindness risk and supporting future large-scale trials.

Eligibility

Min Age: 40 YearsMax Age: 80 Years

Inclusion Criteria5

Age between 40 and 80 years.
Diagnosed with Type 2 diabetes mellitus.
Diagnosed with mild to moderate non-proliferative diabetic retinopathy (NPDR) with a DR Severity Score (DRSS) grade of 20-47D.
Capable of performing daily activities independently.
Willing and able to provide informed consent.

Exclusion Criteria17

Presence of diabetic macular edema (macular thickness \> 250 μm).
Significant eye diseases affecting evaluation, such as high myopia, severe cataract, corneal leucoma, glaucoma, retinal detachment, retinal vein occlusion, congenital eye diseases, ocular tumors, or severe infection.
History of ocular laser or intraocular surgery.
Poor imaging quality due to refractive media opacity.
Contraindication to fluorescein fundus angiography.
Unstable blood glucose (HbA1c ≥ 8.0%) despite oral antidiabetic drugs.
Severe diabetes complications within the past 6 months.
Severe, sustained hypertension (systolic ≥ 180 mmHg or diastolic ≥ 110 mmHg).
Body mass index (BMI) ≥ 28 kg/m².
Hepatic or renal insufficiency: Alanine aminotransferase or aspartate aminotransferase \> 2 times the upper limit of normal. Estimated glomerular filtration rate (eGFR) \< 60 mL/min/1.73m². Urine albumin/creatinine ratio ≥ 30 mg/g.
Myocardial infarction within the past 6 months.
Neurological diseases such as Alzheimer's, Parkinson's, cerebrovascular disease, intracranial tumor, cerebrovascular malformation, or aneurysm.
Contraindications to RIC, including one-sided subclavian artery stenosis, upper limb injuries or vascular diseases, or limb deformities.
Severe systemic diseases, such as malignant tumors with a life expectancy of less than 24 months.
Known pregnancy or breastfeeding.
Participation in other experimental clinical studies.
Any other conditions deemed unsuitable by the investigator.

Interventions

DEVICERemote Ischemic Conditioning Device

Participants in this group will use a remote ischemic conditioning device that applies five cycles of 5-minute inflation at 200 mmHg followed by 5-minute deflation on both arms, twice daily, for at least five days per week over one year. The device is designed to enhance retinal oxygenation and reduce hypoxia-related damage.

DEVICESham Remote Ischemic Conditioning Device

Participants in this group will use the same remote ischemic conditioning device set to an inflation pressure of 60 mmHg to simulate the treatment. This placebo intervention follows the same timing and cycle frequency as the active intervention group.