Aims: Hyperkalemia (HK) is prevalent in patients with chronic kidney disease (CKD) and heart failure, particularly those on renin-angiotensin-aldosterone system inhibitors (RAASi). However, HK treatment often necessitates RAASi discontinuation. Sodium zirconium cyclosilicate (SZC), reimbursed in Italy since 2021, offers a new treatment option for HK. This study aimed to assess real-world SZC use and resulting economic rebounds in Italy.

Methods: Using administrative databases of healthcare entities covering about 6 million residents, patients with at least one prescription of SZC from Jan-2022 to Jun-2023 were identified. Patients receiving other potassium binders after SZC initiation were excluded. A logistic regression model estimated odds ratios (OR) with 95% confidence interval (95%CI) for predictors of long-term SZC use (>90 days), including age, sex, CKD status, and comorbidities. Univariate regression identified the potential association between each individual predictor and the likelihood of long-term treatment, followed by multivariate analysis adjusted for confounders. A backward stepwise logistic regression method retained only significant predictors, enhancing model accuracy.

Results: The study identified 355 SZC-treated patients (mean age 70.4 years, 64.2% male). CKD was found in 69.3% (47.6% on dialysis), with common comorbidities including hypertension (57.5%), diabetes (43.4%), and heart failure (23.4%). RAASi use was observed in 68.7% before SZC initiation, and RAASi discontinuation was lower in long-term SZC users compared to short-term SZC users (41.2 vs. 56.6%, p = 0.048). Short-term SZC treatment (≤90 days) was more frequent (83.1%) and predicted by dialysis (OR = 0.22). Healthcare costs over 6 months averaged €7,943 for short-term users (dialysis: €3,452) and €6,647 for long-term users (dialysis: €1,130).

Conclusions: This real-world study showed that nearly 17% of patients continued SZC therapy for ≥90 days. Long-term therapy was associated with lower RAASi discontinuation and reduced healthcare costs due to hospitalizations and outpatient specialist services, suggesting that SZC can potentially provide clinical and economic benefits for HK management.

Keywords: Chronic kidney disease; I10; I15; healthcare resource utilization; hyperkalemia; real-world evidence; renin-angiotensin-aldosterone system inhibitors; sodium zirconium cyclosilicate.

目的： 高钾血症（HK）在慢性肾病（CKD）和心力衰竭患者中普遍存在，尤其是那些使用血管紧张素-醛固酮系统抑制剂（RAASi）的患者。然而，治疗高钾血症常常需要停止使用RAASi。意大利自2021年以来报销了钠锆环硅酸盐（SZC），为治疗HK提供了新的选择。本研究旨在评估意大利实际应用中的SZC使用情况及其带来的经济效应。

方法： 利用覆盖约600万居民的医疗实体行政数据库，识别了2022年1月至2023年6月期间至少有一份SZC处方记录的患者。排除在启动SZC治疗后使用其他钾结合剂的患者。采用逻辑回归模型估计长期使用SZC（>90天）的风险比（OR），包括年龄、性别、CKD状态和合并症等预测因素，计算出95%置信区间（95%CI）。单变量回归分析了每个单一预测因子与长期治疗的可能性之间的潜在关联，并进行了多变量分析以调整混杂因素。采用逐步向后逻辑回归方法保留显著的预测因子，提高模型精度。

结果： 研究识别出355名使用SZC的患者（平均年龄70.4岁，64.2%为男性）。CKD患者占69.3%，其中47.6%接受透析治疗。常见的合并症包括高血压（57.5%）、糖尿病（43.4%）和心力衰竭（23.4%）。在启动SZC治疗前，RAASi使用率为68.7%，长期使用SZC的患者中RAASi停药率较低（41.2% vs 56.6%，p = 0.048）。短期使用SZC（≤90天）更常见（83.1%），透析治疗是预测因子之一，OR值为0.22。六个月的医疗费用平均为7,943欧元（接受透析者：3,452欧元）和6,647欧元（长期使用者：1,130欧元）。

结论： 这项真实世界研究表明，近17%的患者继续使用SZC治疗超过90天。长期治疗与较低的RAASi停药率和由于住院及门诊专科服务减少而降低的医疗费用相关，表明SZC可能为高钾血症管理提供临床和经济上的益处。

关键词： 慢性肾病；I10；I15；医疗资源利用；高钾血症；真实世界证据；血管紧张素-醛固酮系统抑制剂；钠锆环硅酸盐。