Supplementary Material for: Larger degree of renal function decline in CKD is a favorable factor for the attenuation of eGFR slope worsening by SGLT2 inhibitors: a retrospective observational study

Introduction: Sodium-glucose cotransporter 2 inhibitors (SGLT2Is) have beneficial effects on the renal function of chronic kidney disease (CKD) patients, although the types of patients suitable for this treatment remain unclear. Methods: A retrospective observational study was conducted on CKD patients who were treated with SGLT2I at our department from 2020 to 2023. The estimated glomerular filtration rate (eGFR) just before treatment was defined as the baseline and the difference between pre-and post-treatment eGFR slopes were used to compare the improvement of renal function. Logistic regression analysis was used to evaluate the independent factors for its improvement. Results: A total of 128 patients were analyzed (mean age: 67.2 years; number of women: 28 [22%]). The mean eGFR was 42.1 ml/min/1.73 m2, and urine protein was 0.66 g/gCr. The eGFR slopes of patients with an eGFR < 30 ml/min/1.73 m2 were improved significantly after treatment (-0.28 to -0.14 ml/min/1.73 m2/month, P < 0.001) but were worsened in patients with an eGFR ≥ 30 ml/min/1.73 m2. Logistic analysis for the improvement in eGFR slopes showed that women (odds ratio [OR], 5.63; 95% confidence interval [CI], 1.16 to 27.3; P = 0.03), use of mineral corticoid receptor antagonists (OR, 11.79; 95% CI, 1.05 to 132.67; P = 0.012) and rapid decline of eGFR before treatment (OR, 12.8 per ml/min/1.73 m2/month decrease in eGFR; 95% CI, 3.32 to 49.40; P < 0.001) were significant independent variables. Conclusion: SGLT2Is may have beneficial effects especially for rapid decliners of eGFR, including advanced CKD.

研究背景：钠-葡萄糖协同转运蛋白2抑制剂（Sodium-glucose cotransporter 2 inhibitors, SGLT2Is）对慢性肾脏病（chronic kidney disease, CKD）患者的肾功能具有获益作用，但适宜接受该治疗的患者人群仍未明确。

方法：本研究针对2020年至2023年于我科室接受SGLT2Is治疗的CKD患者开展回顾性观察研究。将治疗前即刻测得的估算肾小球滤过率（estimated glomerular filtration rate, eGFR）设定为基线水平，通过对比治疗前后eGFR的斜率变化评估肾功能改善情况；采用Logistic回归分析评估肾功能改善的独立影响因素。

结果：本研究共纳入128例患者进行分析，平均年龄67.2岁，其中女性28例，占比22%。受试者的平均eGFR为42.1 ml/min/1.73 m²，尿蛋白水平为0.66 g/gCr。基线eGFR＜30 ml/min/1.73 m²的患者，治疗后eGFR斜率显著改善（从-0.28 ml/min/1.73 m²/月升至-0.14 ml/min/1.73 m²/月，P＜0.001）；而基线eGFR≥30 ml/min/1.73 m²的患者则出现肾功能恶化。针对eGFR斜率改善的Logistic回归分析显示，女性（优势比[odds ratio, OR]=5.63；95%置信区间[95% confidence interval, CI]=1.16~27.3；P=0.03）、盐皮质激素受体拮抗剂（mineral corticoid receptor antagonists）的使用（OR=11.79；95%CI=1.05~132.67；P=0.012）以及治疗前eGFR快速下降（每降低1 ml/min/1.73 m²/月的eGFR降幅对应OR=12.8；95%CI=3.32~49.40；P＜0.001）为显著的独立影响因素。

结论：SGLT2Is或可对CKD患者的肾功能产生获益，尤其适用于eGFR快速下降的患者，包括晚期CKD患者。