How to perform better intervention to prevent and control diabetic retinopathy among patients with type 2 diabetes: A meta-analysis of randomized controlled trials.

This meta-analysis of randomized controlled trials (RCTs) aims to investigate how to perform better interventions targeting modifiable risk factors of diabetic retinopathy (DR) to prevent and control DR in patients with type 2 diabetes by comparing different intervention types and follow-up intervals. Literature published before June 1st, 2019 were searched on Pubmed, Embase and ScienceDirect. RCTs targeting modifiable risk factors of DR (including blood glucose, blood pressure, lipid, dietary, physical activity and smoking) were selected by two reviewers and double checked for accuracy. Random effects models were estimated to calculate pooled Odds Ratios (OR). Twenty-two RCTs (n = 22,511) were included. In general, interventions targeting modifiable risk factor of DR reduced the risk of developing DR (I2 = 26.7%; OR = 0.60; 95% CI 0.45 to 0.79) and DR worsening (I2 = 0.0%; OR = 0.62; 95% CI 0.47 to 0.80; P < 0.001). Multifactorial interventions had better effect on reducing the risk of development and progression of DR in comparison with other interventions, while only blood-pressure-control interventions showed significant effect on slowing down DR worsening. Additionally, interventions with follow-up >5 years had better effect on reduction of DR development, and interventions with follow-up >2 years had better effect on reducing the risk of DR worsening.