Li Jim Zhiming, Willke Richard J, Rittenhouse Brian E, Glick Henry A
Global Outcomes Research, Pharmacia Corporation, Peapack, New Jersey, USA.
Pharmacotherapy. 2002 Feb;22(2 Pt 2):45S-54S. doi: 10.1592/phco.22.4.45s.33654.
As length of hospital stay (LOS) represents about 70-90% of the total cost of treating serious infections, it represents a key variable in analyzing the health economic differences between treatments for hospitalized patients. In a retrospective analysis using LOS data from a multinational, randomized, phase III clinical trial, we examined two methods (the log-logistic model and Kaplan-Meier survival function) and three approaches (unadjusted total LOS, total LOS adjusted for nontreatment factors, and adjusted LOS based on antibiotic treatment [the antibiotic treatment LOS]) for estimating antibiotic treatment effect on LOS and determined if these approaches could reduce the variation in LOS and control for the imbalance between treatment groups. The trial enrolled patients who were hospitalized with known or suspected Staphylococcus species infections who received at least one dose of linezolid or vancomycin (intent-to-treat sample) and who continued taking the study drug for at least 7 days (clinically evaluable sample). In the intent-to-treat sample, the linezolid group had a 2- (unadjusted) or 4-day (adjusted for nontreatment factors) shorter LOS at the 25th percentile; a 1- or 2-day advantage, respectively, at the 50th percentile (median); and a 0.6- or 1.6-day mean LOS advantage, compared with the vancomycin group. With the antibiotic treatment LOS approach, the linezolid group had mean and median LOS reductions comparable to or greater than those seen in the nontreatment-factor-adjusted results. Results for the clinically evaluable sample were similar to those of the intent-to-treat sample, but the differences between the treatment groups were greater. Linezolid-treated patients had significant LOS reductions that otherwise would be masked without the use of more appropriate, but less commonly used, methods.
由于住院时间（LOS）约占治疗严重感染总成本的70%-90%，它是分析住院患者不同治疗方法之间健康经济差异的关键变量。在一项使用来自多国、随机、III期临床试验的LOS数据进行的回顾性分析中，我们研究了两种方法（对数逻辑模型和Kaplan-Meier生存函数）和三种途径（未调整的总LOS、针对非治疗因素调整的总LOS以及基于抗生素治疗的调整LOS [抗生素治疗LOS]）来估计抗生素治疗对LOS的影响，并确定这些途径是否可以减少LOS的变异性并控制治疗组之间的不平衡。该试验纳入了因已知或疑似葡萄球菌属感染而住院、接受至少一剂利奈唑胺或万古霉素治疗的患者（意向性治疗样本），以及继续服用研究药物至少7天的患者（临床可评估样本）。在意向性治疗样本中，在第25百分位数时，利奈唑胺组的LOS比万古霉素组短2天（未调整）或4天（针对非治疗因素调整）；在第50百分位数（中位数）时，分别有1天或2天的优势；平均LOS优势为0.6天或1.6天。采用抗生素治疗LOS途径时，利奈唑胺组的平均和中位数LOS降低幅度与非治疗因素调整后的结果相当或更大。临床可评估样本的结果与意向性治疗样本相似，但治疗组之间的差异更大。接受利奈唑胺治疗的患者的LOS显著降低，否则如果不使用更合适但较少使用的方法，这些降低可能会被掩盖。
