Electrolyte and acid-base disorders in cancer patients and its impact on clinical outcomes: evidence from a real-world study in China

This study aims to delineate the incidence of electrolyte and acid-base disorders (EAD) in cancer patients, to figure out the risk factors of EAD, then to assess the impact of EAD on patients’ in-hospital clinical outcomes. Patients with the diagnosis of malignancies hospitalized during 1 October 2014 and 30 September 2015 were recruited in Zhongshan Hospital, Fudan University in Shanghai of China. Demographic characteristics, comorbidities, and clinical data, including survival, length of stay and hospital cost, were extracted from the electronic medical record system. Electrolyte and acid-base data were acquired from the hospital laboratory database. Of 25,881 cancer patients with electrolyte data, 15,000 (58.0%) cases had at least one electrolyte and acid-base abnormity. Hypocalcemia (27.8%) was the most common electrolyte disorder, followed by hypophosphatemia (26.7%), hypochloremia (24.5%) and hyponatremia (22.5%). The incidence of simple metabolic acidosis (MAC) and metabolic alkalosis (MAL) was 12.8% and 22.1% respectively. Patients with mixed metabolic acid-base disorders (MAC + MAL) accounted for 30.2%. Lower BMI score, preexisting hypertension and diabetes, renal dysfunction, receiving surgery/chemotherapy, anemia and hypoalbuminemia were screened out as the major risk factors of EAD. In-hospital mortality in patients with EAD was 2.1% as compared to those with normal electrolytes (0.3%). The risk of death significantly increased among patients with severe EAD. Similarly, the length of stay and hospital cost also tripled as the number and grade of EAD increased. EAD is commonly encountered in cancer patients and associated with an ominous prognosis. Patients with comorbidities, renal/liver dysfunction, and anti-tumor therapy have a higher risk of EAD. Regular monitoring of electrolytes, optimum regimen for intravenous infusion, timely correction of modifiable factors and appropriate management of EAD should not be neglected during anti-tumor treatment.

本研究旨在阐明癌症患者电解质与酸碱平衡紊乱（electrolyte and acid-base disorders, EAD）的发生情况，明确其危险因素，并评估EAD对患者住院临床结局的影响。本研究纳入2014年10月1日至2015年9月30日期间，于中国上海复旦大学附属中山医院住院的恶性肿瘤确诊患者作为研究对象。从电子病历系统中提取患者的人口学特征、合并症及临床数据，包括生存情况、住院时长与住院费用；电解质与酸碱平衡相关数据则来源于医院检验数据库。在纳入的25881例拥有电解质检测数据的癌症患者中，共15000例（58.0%）存在至少1种电解质或酸碱平衡异常。低钙血症（27.8%）为最常见的电解质紊乱，依次为低磷血症（26.7%）、低氯血症（24.5%）与低钠血症（22.5%）。单纯性代谢性酸中毒（metabolic acidosis, MAC）与单纯性代谢性碱中毒（metabolic alkalosis, MAL）的发生率分别为12.8%与22.1%；混合性代谢性酸碱紊乱（MAC+MAL）患者占比达30.2%。经筛选，较低的体质量指数（BMI）、既往合并高血压与糖尿病、肾功能不全、接受手术/化疗治疗、贫血以及低白蛋白血症为EAD的主要危险因素。合并EAD的患者院内死亡率为2.1%，而电解质与酸碱指标正常的患者院内死亡率仅为0.3%；重度EAD患者的死亡风险显著升高。与之类似，随着EAD的发生数量与严重程度升高，患者的住院时长与住院费用均增长至原来的三倍。EAD在癌症患者中较为常见，且与不良预后密切相关。合并基础疾病、肝肾功能不全以及接受抗肿瘤治疗的患者，发生EAD的风险更高。在抗肿瘤治疗过程中，不应忽视电解质的定期监测、优化静脉输液方案、及时纠正可干预的危险因素，并对EAD采取恰当的干预措施。