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Published online: 2024-06-03

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Time in Range: Unveiling the Correlation with Diabetic Retinopathy in Type 2 Diabetes: A Systematic Review and Meta-Analysis

Kevin Gracia Pratama1, Maria Angelia2, Yufilia Suci Amelia3, Norman Sukmadi3


Objective: Research has established an association between glycemic control and retinopathy progression; however, the use of continuous glucose monitoring (CGM) and diabetic retinopathy (DR) progression remains less explored. Our study aims to explore the link between time in range (TIR) and DR and its clinical implications. Materials and methods: Following the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) 2020 guideline, we conducted a systematic review by searching databases such as PubMed, EBSCO, and ProQuest, supplemented by manual exploration. Studies reporting TIR or other CGM-derived metrics in association with DR were included. The quality of each study was evaluated using the Newcastle-Ottawa Scale (NOS). Review Manager 5.4 software, was used to performed a meta-analysis with random-effects model. Results: The meta-analysis of five studies indicated significant associations between CGM-derived metrics and diabetic retinopathy. TIR exhibited a mean difference of –6.44 (95% CI: –8.10, –4.78, p < 0.001), standard deviation (SD) showed a mean difference of 0.20 (95% CI: 0.16, 0.24, p < 0.001), mean amplitude of glycemic excursion (MAGE) displayed a mean difference of 0.45 (95% CI: 0.31, 0.58, p < 0.001), and coefficient of variation (CV) demonstrated a mean difference of –0.99 (95% CI: 0.43, 1.55, p = 0.0006). Stratification by TIR percentage (< 70% vs. ≥ 70%) revealed an odds ratio of 2.06 (95% CI: 0.85, 4.97, p = 0.11) for diabetic retinopathy risk, although statistically insignificant. Conclusions: Lower TIR is significantly associated with DR in T2D patients. Furthermore, higher SD, MAGE, and CV were linked to the presence of DR.

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