腹膜透析患者初始血清白蛋白的變化及趨勢影響患者存活之探討

Effect of alteration and trend of serum albumin after dialysis on survival of peritoneal dialysis patients

邱炳芳(Ping-Fang Chiu)

指導教授 ： 張浤榮

中山醫學大學/醫學院/醫學研究所/博士(2016年)

摘要

研究目的：以前許多研究指出，剛透析時的初始血清白蛋白程度與腹膜透析（peritoneal dialysis）患者的總死亡率和心血管死亡率呈現負相關，但是我們認為在透析後血清白蛋白的動態變化和趨勢將可能更會影響腹膜透析患者的死亡率。
研究方法及資料：我們收集了從1999年1月至2014年3月期間，這15年內，在彰化基督教醫院因各種原因導致尿毒症(末期腎病變)而進行了三個月以上腹膜透析患者，透析後營養及整體狀況會有變化，血清白蛋白最高峰值(peak albumin)與最初進入透析時血清白蛋白(initial albumin)數值的差異值稱作△血清白蛋白(increment增值)，然後依所有收案患者差異值的中位數，我們將這些患者劃分為兩組。A組患者（人數=238）: △血清白蛋白<0.2克/百毫升，而△血清白蛋白≥0.2克/百毫升則被歸類為B組（人數=278）。此外，進而我們再將這些患者分層成四組： Q1組△白蛋白< ̶ 0.2克/百毫升; Q2組 ̶ 0.2≦〜<0.2克/百毫升; Q3組，0.2≦〜<0.6克/百毫升;和Q4組，≥0.6克/百毫升。分析這些組別間的最終死亡率差異，最後我們再將這些資料進行多重回歸模式分析，以了解最初透析時初始白蛋白和△白蛋白的相關性。
研究結果：A組患者雖然有較高的透析初始血清白蛋白（平均值3.71±0.54克/百毫升和3.04±0.55克/百毫升; 與B組患者比較，P值 <0.001）和較少比例的貧血(較高的血容比)，以及較佳的殘餘腎功能。然而，這些A組患者卻在透析開始後，血清白蛋白有降低的趨勢，而使得血清白蛋白最高峰值與最初進入透析時血清白蛋白數值的差異值(△白蛋白)較低。相反地，B組患者在透析開始後，血清白蛋白趨勢及其軌跡是持續上升的，而使得血清白蛋白最高峰值與最初進入透析時血清血清白蛋白數值的差異有顯著的提升，儘管B組患者在進入透析時有較高比例已罹有心血管疾病和糖尿病。隨著透析時間的進展，最終A組患者存活率結果是較差的。進一步分析得知，這組患者透析後經歷更加頻繁和更長的住院治療。再進一步將這些患者分層後， Q1組患者因透析後血清白蛋白差異值最少(△血清白蛋白)而使得存活率最差。Q4組患者其透析後初始血清白蛋白最低，存活率次差。多重回歸分析發現：患者進入腹膜透析時年齡，糖尿病，心血管疾病，身體質量指數，透析後初始血清白蛋白和△血清白蛋白，皆能獨立影響患者的最終存活。線性回歸分析得知，透析後初始血清白蛋白至少須高於3.15克/升時，在經過透析之後身體狀況及營養改善後，會因血清白蛋白會增加，而得到一個較好△血清白蛋白的結果。（透析後初始血清白蛋白= -0.61×△血清白蛋白 + 3.50）
結論：作為身體狀況的綜合指標，血清白蛋白濃度是至關重要的，無論在透析哪個階段，包括腹膜透析初開始，透析穩定時期，或是腹膜透析結束轉入血液透析時，時間點上血清白蛋白濃度值皆能預測患者的存活率。但是，透析後血清白蛋白提升和變化的趨勢，對最終患者的存活也是很重要的。因此，藉著延續慢性腎臟病第五階段的全面的團隊照顧及精心規劃的飲食控制，達到透析後最佳身體及營養狀況，腹膜透析患者會有最佳的存活預後。

關鍵字

腹膜透析 ； 白蛋白的趨勢 ； 白蛋白差異值 ； 白蛋白軌跡

並列摘要

Objective：Although initial serum albumin level is highly associated with overall and cardiovascular mortality in peritoneal dialysis (PD) patients, we consider that the dynamic change and trend of albumin after initiation of PD are also essential.
Methods and Materials：We enrolled patients who received PD for more than 3 months from January 1999 to March 2014. We categorized these patients into two groups by the difference in serum albumin level (△albumin = difference between peak with initial albumin level = peak albumin level − initial albumin level) after PD. The patients with △albumin < 0.2 g/dL (median level) were considered as group A (N = 238) and those with △albumin ≥ 0.2 g/dL were considered as group B (N = 278). Further, we stratified these patients into quartiles: Q1 △albumin < −0.2 g/dL; Q2, −0.2≦~ < 0.2 g/dL; Q3, 0.2≦~ <0.6 g/dL; and Q4, ≥ 0.6 g/dL. Regression analysis was performed to determine the correlation of initial albumin and △albumin.
Results：Group A patients presented with higher levels of serum albumin (3.71 ± 0.54 g/dL vs 3.04 ± 0.55 g/dL; p < 0.001) and hematocrit as well as better initial residual renal function. However, those in group A had lower serum albumin increment and downward-sloped trends after dialysis. In contrast, the albumin trend was upward sloped and the increment of albumin was remarkable in group B, despite the high prevalence of cardiovascular diseases and diabetes. Over time, group A patients had poorer survival and experienced more frequent and longer hospitalizations. Group Q1 patients with least albumin increment had worst survival. Group Q4 patients with lowest initial albumin also had poor survival. Age, diabetes, cardiovascular diseases, BMI, initial albumin and △albumin, could affect patient outcomes independently. Regression analysis showed a better outcome can be obtained if the initial albumin level is at least above 3.15 g/dL.( Initial albumin level = −0.61 × △albumin + 3.50)
Conclusion：serum albumin is critical and predictive for patients’ survival, regardless of the dialysis state. Additionally, the albumin increment and its trend after dialysis are also important in this aspect. Therefore, by maintaining well-planned diet control in CKD stage 5 and continuously comprehensive care following PD, the patients can ultimately have favor survival.

並列關鍵字

peritoneal dialysis ； albumin trend ； albumin difference ； trajectory of albumin

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