With the advances in blood glucose monitoring technologies, a flash glucose monitoring system (FGMS) has recently been used to panoramically observe the blood glucose level in patients with type 2 diabetes mellitus (T2DM). Evaluating the relationship of blood glucose metrics monitored by the FGMS with T2DM complications will facilitate the clinical application of FGMS but relevant studies are rare.

To assess the correlation of time in range (TIR) and other markers with urine albumin-to-creatinine ratio (UACR) in patients with T2DM using a FGMS.

T2DM patients (n=79) using a FGMS were selected from Department of Geriatrics, Peking University People's Hospital from January 2019 to October 2021, including 29 with UACR greater than 30 mg/g (albuminuria group) and 50 with UACR less than 30 mg/g (non-albuminuria group). The clinical characteristics, laboratory test markers, and blood glucose metrics monitored by the FGMS of the two groups were compared. Pearson correlation and Spearman correlation analyses were used to explore the correlation of TIR and time above range (TAR) with glycated hemoglobin (HbA_1c). Pearson correlation, Spearman correlation and partial correlation analyses were used to explore the correlations of FGMS markers with natural logarithm-transformed UACR, respectively. Multivariate Logistic regression analysis was used to explore the factors influencing the development of albuminuria in T2DM. The predictive value of TIR for albuminuria was assessed using the receiver operating characteristic (ROC) curve.

Compared with the non-albuminuria group, albuminuria group had longer duration of T2DM (P<0.05). Moreover, albuminuria group had higher triacylglycerol, HbA_1c, mean blood glucose (MBG), TAR, the standard deviation of mean blood glucose (SDBG), the largest amplitude of glycemic excursions (LAGE), mean amplitude of glycemic excursions (MAGE), and 2 h continuous overlapping net glycemic action (CONGA₂), as well as lower TIR (P<0.05). Pearson correlation and Spearman correlation analyses showed that HbA_1c was negatively correlated with TIR (P<0.001), and was positively correlated with TAR (P<0.001). Pearson correlation, Spearman correlation and partial correlation analyses revealed that the natural logarithm-transformed UACR was negatively correlated with TIR (P<0.001), and was positively correlated with MBG, TAR, SDBG, LAGE, MAGE, and CONGA₂ (P<0.001). Multivariable Logistic regression analysis showed that TIR>70%〔OR=0.038, 95%CI (0.003, 0.467) 〕 was associated with decreased risk of albuminuria in T2DM (P<0.05), while elevated TAR〔OR=1.046, 95%CI (1.000, 1.094) 〕 was associated with increased risk of albuminuria in T2DM (P<0.05). The area under the ROC curve of TIR for predicting the presence of albuminuria in T2DM was 0.784 〔95%CI (0.674, 0.894) 〕 (P=0.003), with a sensitivity of 78%, and a specificity of 83% when the optimal cutoff point was chosen as 69.71%.

The risk of albuminuria decreased with TIR>70% but increased with elevated TAR in T2DM. UACR was closely related with SDBG, LAGE, MAGE, CONGA₂ and other markers reflecting blood glucose fluctuations. Early screening and identifying T2DM patients with a low TIR level, and a high TAR, SDBG, LAGE, MAGE, and CONGA₂ will help to prevent the development of albuminuria.

随着血糖监测技术的发展，近些年来人们开始使用扫描式葡萄糖监测系统（FGMS）"全景式"地观察2型糖尿病（T2DM）患者的血糖水平，明确FGMS指标与T2DM并发症之间的关系有助于提高其临床应用价值，但目前相关研究较少。

探究佩戴FGMS的T2DM患者葡萄糖在目标范围内时间（TIR）等指标与尿白蛋白/肌酐比值（UACR）的相关性。

选取2019年1月至2021年10月于北京大学人民医院老年科就诊并佩戴FGMS的T2DM患者79例，以尿液检查中UACR是否<30 mg/g将患者分为无白蛋白尿组（n=50）和白蛋白尿组（n=29）。比较两组患者的临床特征、实验室检查指标及FGMS指标等。采用Pearson相关、Spearman秩相关分析探讨TIR、高血糖时间（TAR）与糖化血红蛋白（HbA_1c）的相关性。分别采用Pearson相关、Spearman秩相关、偏相关分析探讨FGMS指标与lnUACR的相关性。使用多因素Logistic回归分析探究T2DM患者发生白蛋白尿的影响因素，采用受试者工作特征（ROC）曲线评估TIR对白蛋白尿的预测价值。

白蛋白尿组T2DM病程长于无白蛋白尿组，三酰甘油（TG）、HbA_1c、平均血糖（MBG）、TAR、平均血糖标准差（SDBG）、最大葡萄糖波动幅度（LAGE）、平均葡萄糖波动幅度（MAGE）、连续每隔2 h血糖净作用（CONGA₂）高于无白蛋白尿组，TIR低于无白蛋白尿组（P<0.05）。Pearson相关、Spearman秩相关分析结果显示，TIR与HbA_1c呈负相关（P<0.001），TAR与HbA_1c呈正相关（P<0.001）。Pearson相关、Spearman秩相关、偏相关分析结果均表明，TIR与lnUACR呈负相关（P<0.001），MBG、TAR、SDBG、LAGE、MAGE、CONGA₂与lnUACR呈正相关（P<0.001）。多因素Logistic回归分析结果显示，TIR>70%〔OR=0.038，95%CI（0.003，0.467）〕是T2DM患者出现白蛋白尿的保护因素（P<0.05），TAR升高〔OR=1.046，95%CI（1.000，1.094）〕是T2DM患者出现白蛋白尿的危险因素（P<0.05）。TIR预测T2DM患者出现白蛋白尿的ROC曲线下面积（AUC）为0.784〔95%CI（0.674，0.894）〕（P=0.003），灵敏度为78%，特异度为83%，最佳切点为69.71%。

在FGMS指标中，TIR>70%是T2DM患者出现白蛋白尿的保护因素，TAR升高是T2DM患者出现白蛋白尿的危险因素。同时，SDBG、LAGE、MAGE、CONGA₂等多种反映血糖波动的指标也与UACR密切相关。对TIR水平较低及TAR、SDBG、LAGE、MAGE、CONGA₂水平较高的T2DM患者进行FGMS筛查有助于早期识别及预防白蛋白尿的发生、发展。