以體外震波碎石術治療泌尿道結石其結石廓清率及影響結石復發之相關因素──以中部某區域醫院為例

The Stone-Free Rate and Risk Factors for Recurrence after Extracorporeal Shock Wave Lithotripsy

研究背景及目的：尿路結石是泌尿系統最常見的疾病之一，體外震波碎石術（ESWL）是最常被利用的治療方法，而我國健保制度自開辦以來，一直是以論病例計酬方式支付醫療費用，體外震波碎石術的支付點數在門診各項診療項目中為單次給付之冠，結石治療情形及復發與否皆是影響ESWL醫療費用的主要原因之一。本研究除瞭解以體外震波碎石術治療泌尿道結石的廓清情形，並分析影響結石復發之相關因素。方法：本研究以中部某區域醫院自2000年7月至2001年6月間，接受ESWL治療之結石患者為對象，共計706人，以病例回顧的方式，追蹤其結石是否完全廓清及五年內復發情形，並進一步以羅輯斯迴歸分析，來瞭解影響結石廓清率的相關因素，同時利用存活分析來探討結石病患在接受ESWL治療且完治後，影響其再次復發的顯著相關因素。結果：在接受ESWL治療之病患中，男性有506人，女性200人。年齡最大86歲，最小16歲，平均年齡為47.23歲。本研究以腎臟為觀察單位(renal unit)，在接受治療的763個單位中，未完全廓清有324個單位，完全廓清的為439個單位，廓清率為57.54％，完全廓清者中再復發的比率為28%。影響結石廓清的顯著相關因素為結石大小、結石數目及結石位置，結石愈大、數目愈多，則愈不容易廓清，而「上端輸尿管結石」及「上腎盞結石」廓清機率顯著高於「下腎盞結石」。影響結石治療復發之顯著相關因素為病患年齡及結石位置，隨著年齡增加結石復發機率降低，「上端輸尿管結石」患者復發機率顯著低於「下腎盞結石」患者。結論：對泌尿道結石而言，體外震波碎石術是一項有效的治療方式，然而結石的低廓清率及高復發率都會提高體外震波碎石治療之次數，進而增加醫療成本之耗用。依據病患的疾病狀態，選擇做合適的治療方法，有助於提高結石的廓清率。此外，除病患年齡及結石位置，經由適當的衛教將有助於降低結石復發的可能。

Objectives: Since the implementation of National Health Insurance, the payment method has been fee-for-service and the highest payment unit for medical equipment usage has been outpatient treatment with extracorporeal shock wave lithotripsy (ESWL). The aim of this study was to determine the stone-free rate after ESWL and to analyze the factors that affected the recurrence rate. Materials and Methods: Between Jul 2000 and Jun 2001, a total of 706 patients underwent ESWL in Cheng-Ching General Hospital.We retrospectively reviewed the stone-free and recurrence rates after ESWL and investigated the factors that contributed to those rates with logistic regression analysis. Results: There were 506 males and 200 females in this study. The mean age was 47.23 years and the range was from 16 to 86. A total of 763 renal units were enrolled. Of these, 439(57.53%) were stone-free after ESWL and the other 324 were not.Stones recurred in 123 of the 439 stone-free renal units (28%).Stone size , number, and location were significant factors that affected the stone-free rate. The stone free rates for upper ureteral and upper renal calyceal stones were higher than the rate for lower calyceal stones. Patients with an early onset of stone formation had higher recurrence rates. Lower calyceal stones recurred more frequently than upper ureteral stones. Conclusions: ESWL is a less invasive and more effective method for rolithiasis.however, the lower stone-free rate and higher recurrence rate result in higher utilization of ESWL. A complete image study and a proper management will increase the stone -free rate. Other factors such as age and stone location and education about changing diet habits and life style are also important.