Objectives

Cystectomy with urinary diversion is associated with decreased long-term kidney function due to several factors. One factor that has been debated is the type of urinary diversion used: ileal conduit (IC) vs. neobladder (NB). We tested the hypothesis that long-term kidney function will not vary by type of urinary diversion.

Methods and Materials

We retrospectively identified all patients who underwent cystectomy with urinary diversion at our institution from January 1, 2007, to January 1, 2018. Data were collected on patient demographics, comorbid conditions, perioperative radiotherapy, and complications. Creatinine values were measured at several time points up to 120 months after surgery. Glomerular filtration rate (GFR) (ml/min per 1.73 m²) was calculated using the Chronic Kidney Disease Epidemiology Collaboration equation. A linear mixed model with inverse probability of treatment weighting (IPTW) was used to compare GFR between the IC and NB cohorts over time. Multiple sensitivity analyses were performed based on 2 different calculations of GFR (Chronic Kidney Disease Epidemiology Collaboration equation vs. Modification of Diet in Renal Disease), with and without excluding patients with preoperative GFR less than 40 ml/min per 1.73 m².

Results

Among 563 patients who underwent cystectomy with urinary diversion, a NB was used for 72 (12.8%) individuals. Patients who had a NB were significantly younger, had a lower American Society of Anesthesiologists score, greater baseline GFR, better Eastern Cooperative Oncology Group performance status, lower median Charlson comorbidity index, and were less likely to have received preoperative abdominal radiation (all P < 0.05). Both NB and IC patients had decreased kidney function over time, with mean GFR losses at 5 years of 17% and 14% of baseline values, respectively. The IPTW-adjusted linear mixed model revealed that IC patients had slightly more deterioration in kidney function over time, but this was not statistically significant (estimate, 0.12; P = 0.06). The sensitivity analyses yielded a similar trend, in that GFR decrease appeared to be greater in the IC cohort. This trend was statistically significant when using Modification of Diet in Renal Disease (P = 0.04).

Conclusions

Among highly selected patients with an NB, deterioration of kidney function may potentially be lower over time than among IC patients. However, the statistical significance varied between analyses and we cautiously attribute these observed differences to patient selection.

中文翻译：

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膀胱切除术后尿液转移对长期肾脏功能的影响。

目标

由于多种因素，伴有尿液转移的膀胱切除术与长期肾功能下降有关。争论的一个因素是使用的尿液改道类型：回肠导管（IC）与新膀胱（NB）。我们检验了长期肾脏功能不会因尿流改道类型而改变的假设。

方法与材料

我们回顾性分析了我们机构从2007年1月1日至2018年1月1日接受膀胱切除术并进行尿路改道手术的所有患者。收集了有关患者人口统计学，合并症，围手术期放疗和并发症的数据。在手术后直至120个月的多个时间点测量肌酐值。肾小球滤过率（GFR）（ml / min每1.73 m ²使用慢性肾脏病流行病学协作方程计算。使用具有治疗加权权重反比（IPTW）的线性混合模型来比较IC和NB队列之间随时间变化的GFR。基于GFR的两种不同计算（慢性肾脏病流行病学协作方程与肾脏疾病饮食的调整）进行了多重敏感性分析，有无排除术前GFR低于40 ml / min每1.73 m ^2的患者。

结果

在563例因膀胱改道而进行尿液转移的患者中，NB用于72例（12.8％）。患有NB的患者明显年轻，美国麻醉医师学会评分较低，基线GFR较高，东部合作肿瘤小组的表现更好，Charlson合并症中位数较低，并且接受术前腹部放疗的可能性较小（所有P < 0.05）。NB和IC患者的肾脏功能均随时间下降，其5年平均GFR损失分别为基线值的17％和14％。经IPTW调整的线性混合模型显示，随着时间的流逝，IC患者肾功能的恶化程度略高，但这在统计学上无统计学意义（估计值为0.12；P = 0.06）。敏感性分析得出了类似的趋势，因为IC队列中的GFR下降似乎更大。当在肾脏疾病中使用饮食调整法时，这种趋势具有统计学意义（P  = 0.04）。

结论

在高度选择的NB患者中，随着时间的流逝，肾功能的恶化可能会比IC患者低。但是，分析之间的统计显着性不同，我们谨慎地将这些观察到的差异归因于患者选择。