Mehta Kathan, Appleman Leonard, Wang Hong, Tarhini Ahmad A, Parikh Rahul A
University of Pittsburgh Medical Center, Pittsburgh, PA, United States of America.
University of Pittsburgh Cancer Institute, Pittsburgh, PA, United States of America.
PLoS One. 2016 Jan 22;11(1):e0147153. doi: 10.1371/journal.pone.0147153. eCollection 2016.
Immunotherapy using high dose interleukin-2 (HD IL2) in patients with renal cell carcinoma (RCC) and melanoma is associated with severe toxicities. The association between annual hospital volume of HD IL2 and inpatient mortality is not well studied. In this study we aim to quantify the impact of annual hospital volume of HD IL2 on inpatient mortality using National Inpatient Sample (NIS) data.
We did a cross-sectional study using NIS, one of the largest inpatient datasets in United States, from 2003 to 2011. Patients with melanoma and RCC receiving HD IL2 were identified by ICD9 procedure code 00.15. The primary outcome was inpatient mortality. Using Joinpoint regression, which detects change in trend of inpatient mortality with change in annual volume, the hospitals were classified in three volume categories (low: 1-40, medium: 41-120, high: >120). Multivariate logistic regression was used to identify predictors of inpatient mortality controlling for confounders.
From 2003 to 2011, 29,532 patients with RCC or melanoma who received HD IL2 were identified, and 124 died during the hospitalization (0.4%). The hospitals with low, medium and high annual volume had significant difference in inpatient mortality (0.83%, 0.29% and 0.13% respectively, p = 0.0003). On multivariate analysis, low volume hospitals were associated with significantly higher odds of inpatient mortality (OR 6.1, 95% CI 1.6-23.2, p = 0.003) as compared to high volume hospitals. Additionally, the hospitals with annual volume of 1-20 had even higher rates (1.31% vs. 0.13%, p<0.0001) and multivariate odds (OR 8.9, 95% CI 2.4-33.2, p = 0.0006) of inpatient mortality as compared to high volume hospitals.
Lower annual hospital volume of HD IL2 is associated with worse outcomes. Annual hospital volume of 1-40 and 1-20 treatments per year is associated with 6 and 9 times higher odds of inpatient mortality respectively as compared to high volume hospitals. Our findings provide preliminary evidence for a volume-outcome relationship for RCC and melanoma patients undergoing HD IL2 treatment. They support future volume-outcome analyses in relation to other anti-cancer therapies that require special training and expertise.
在肾细胞癌（RCC）和黑色素瘤患者中使用高剂量白细胞介素-2（HD IL2）进行免疫治疗会伴有严重毒性。HD IL2的年度医院治疗量与住院患者死亡率之间的关联尚未得到充分研究。在本研究中，我们旨在使用国家住院样本（NIS）数据量化HD IL2的年度医院治疗量对住院患者死亡率的影响。
我们使用NIS进行了一项横断面研究，NIS是美国最大的住院数据集之一，时间跨度为2003年至2011年。通过ICD9程序代码00.15识别接受HD IL2治疗的黑色素瘤和RCC患者。主要结局是住院患者死亡率。使用Joinpoint回归（该方法可检测住院患者死亡率趋势随年度治疗量变化的情况）将医院分为三个治疗量类别（低：1 - 40，中：41 - 120，高：>120）。使用多变量逻辑回归来确定控制混杂因素后的住院患者死亡率预测因素。
2003年至2011年期间，共识别出29,532例接受HD IL2治疗的RCC或黑色素瘤患者，其中124例在住院期间死亡（0.4%）。年度治疗量低、中、高的医院在住院患者死亡率方面存在显著差异（分别为0.83%、0.29%和0.13%，p = 0.0003）。多变量分析显示，与高治疗量医院相比，低治疗量医院的住院患者死亡几率显著更高（比值比6.1，95%置信区间1.6 - 23.2，p = 0.003）。此外，年度治疗量为1 - 20例的医院与高治疗量医院相比，住院患者死亡率更高（1.31%对0.13%，p<0.0001），多变量比值比也更高（比值比8.9，95%置信区间2.4 - 33.2，p = 0.0006）。
HD IL2的年度医院治疗量较低与较差的结局相关。与高治疗量医院相比，每年1 - 40例和1 - 20例的年度医院治疗量分别使住院患者死亡几率高出6倍和9倍。我们的研究结果为接受HD IL2治疗的RCC和黑色素瘤患者的治疗量 - 结局关系提供了初步证据。它们支持未来针对其他需要特殊培训和专业知识的抗癌疗法进行治疗量 - 结局分析。
