Division of Nephrology, Endocrinology and Metabolism, Department of Internal Medicine, Tokai University School of Medicine, 143 Shimokasuya, Isehara, Kanagawa 259-1193, Japan.
Tokai J Exp Clin Med. 2023 Sep 20;48(3):83-90.
We previously reported the mean average relative difference (MARD) of the sensor glucose (SG) of the first-generation FreeStyle Libre with the original algorithm, an intermittent scanning continuous glucose monitoring (isCGM) device, was 15.6% in the Effect of Intermittent-Scanning Continuous Glucose Monitoring to Glycemic Control Including Hypoglycemia and Quality of Life of Patients with Type 1 Diabetes Mellitus Study (ISCHIA Study). In the present study, we aimed to further analyze its accuracy in detail by conducting a post-hoc analysis of the study.
The ISCHIA Study was a multicenter, randomized, cross-over trial to assess the efficacy of isCGM. The SG levels of isCGM and the measured capillary blood glucose (BG) levels of 91 participants were used for the analysis.
Bland-Altman analysis showed bias of -13.0 mg/dl when the SG levels were compared to the BG levels, however no proportional bias was observed ( = 0.085). MARD of the participants without and with contact dermatitis were 15.0 ± 6.0% and 27.4 ± 21.4% ( = 0.001), respectively.
There was negative bias in the SG levels of isCGM compared to the BG levels. There is a possibility that the complication of the contact dermatitis during isCGM use may be related with deteriorated accuracy of the SG levels.
我们之前报道了第一代 FreeStyle Libre 传感器血糖（SG）的原始算法的平均相对差异（MARD）为 15.6%，这是在 1 型糖尿病患者间歇扫描连续血糖监测（isCGM）对血糖控制的影响，包括低血糖和生活质量的 ISCHIA 研究中。在本研究中，我们旨在通过对该研究进行事后分析，进一步详细分析其准确性。
ISCHIA 研究是一项多中心、随机、交叉试验，旨在评估 isCGM 的疗效。分析了 91 名参与者的 isCGM 的 SG 水平和测量的毛细血管血糖（BG）水平。
Bland-Altman 分析显示，当 SG 水平与 BG 水平比较时，存在 -13.0mg/dl 的偏差，但没有观察到比例偏差（=0.085）。无接触性皮炎和有接触性皮炎的参与者的 MARD 分别为 15.0±6.0%和 27.4±21.4%（=0.001）。
与 BG 水平相比，isCGM 的 SG 水平存在负偏差。在使用 isCGM 期间发生接触性皮炎的并发症可能与 SG 水平的准确性恶化有关。
