Remote Ischemic Conditioning

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.

Post-stroke depression (PSD) is characterized primarily by low mood and loss of interest following a stroke. It is one of the most common and serious complications of stroke, with an incidence of 11% to 41% within two years post-stroke. PSD significantly impacts stroke prognosis, not only hindering neurological recovery but also increasing clinical disability and mortality rates, thereby imposing substantial economic and psychological burdens on families and society. Therefore, preventing PSD is crucial for stroke rehabilitation. Clinical trials have demonstrated that preventive antidepressant treatment can reduce PSD incidence and improve clinical outcomes; however, controversies remain regarding the timing, methods, and safety. Meanwhile, preventive psychological therapy faces challenges in implementation due to effectiveness, accessibility, and cost-effectiveness. Remote ischemic preconditioning (RIC) is a non-invasive, cost-effective, and non-pharmacological intervention. By modulating small molecules in the peripheral and central nervous systems through transient, periodic limb blood flow restriction and reperfusion, RIC reverses neurobiological changes and demonstrates neuroprotective potential in various neurological diseases. Recently, a study showed that RIC is safe and effective in preventing PSD; however, the sample size is small and the specific mechanisms remain unclear. Therefore, this study aims to further explore the role and mechanisms of RIC in PSD prevention.

Remote ischemic conditioning (RIC) is the process of repeated ischemia and reperfusion in the peripheral vessels, which is proved in reducing IRI in vital organs. This IMPROVE trial plans to enroll 648 patients who are diagnosed with coronary artery disease and are going to take off-pump CABG in five centers in China, to access whether RIC can and improve short-term prognosis.