Kalantar-Zadeh K, Don B R, Rodriguez R A, Humphreys M H
University of California San Francisco, Division of Nephrology, San Francisco General Hospital, San Francisco, CA, USA.
Am J Kidney Dis. 2001 Mar;37(3):564-72.
We tested the hypothesis that a high concentration of serum ferritin, a frequently used marker of iron stores in dialysis patients and an acute-phase reactant, may be a marker of morbidity and mortality in these patients. To evaluate the impact of ferritin on morbidity and mortality, we reviewed the 6-month hospitalization rates in our dialysis patients retrospectively and subsequently reviewed the mortality among these patients over a 12-month period of time prospectively. One hundred one adult hemodialysis patients (59 men and 42 women; age, 54 +/- 15 years) who had been on hemodialysis for 38 +/- 27 months were studied. All but 5 patients were on intravenous iron with similar iron administration pattern. In the retrospective cohort, ferritin's correlation coefficients for hospitalization days and frequency (both r = +0.39, P: < 0.001) were higher compared with the albumin correlations for hospitalization days (r = -0.31, P: = 0.001) and frequency (r = -0.28, P: = 0.005) and correlation coefficients remained similarly significant after case-mix adjustment. In the prospective study, the "predeath" value of serum ferritin for 17 deceased patients (891 +/- 476 ng/mL) was higher than both their "initial" value (619 +/- 345 ng/mL, P: = 0.007) and the mean ferritin value of 84 surviving and withdrawing patients (639 +/- 358 ng/mL, P: = 0.001). Although Cox proportional hazard analysis showed a significant odds ratio of death only for serum albumin and not for ferritin, logistic regression analysis using the predeath values confirmed the significant impact of both decreased serum albumin and increased serum ferritin as markers of dialysis mortality. After case-mix adjustment, the relative risks of death for a 500 ng/dL increase in serum ferritin was 2.71 (95% confidence interval, 1.06 to 7.02) and for a 0.5 g/dL decrease in serum albumin was 4.48 (95% confidence interval, 1.77 to 11.33). Hence, serum ferritin is a strong predictor of hospitalization in dialysis patients. Although serum albumin is found to be a strong long-term marker of mortality in hemodialysis patients, an increase in serum ferritin appears to be a more reliable short-term marker of death over a 12-month period. Therefore, in the setting of uniform iron administration, a high serum ferritin may be a morbidity risk factor and a recent increase in serum ferritin may carry an increase in the risk of death in these patients.
血清铁蛋白浓度升高,这一在透析患者中常用的铁储存标志物及急性期反应物,可能是这些患者发病和死亡的一个标志物。为评估铁蛋白对发病和死亡的影响,我们回顾性分析了我们透析患者的6个月住院率,随后前瞻性分析了这些患者在12个月期间的死亡率。研究了101例成年血液透析患者(59例男性和42例女性;年龄54±15岁),他们接受血液透析38±27个月。除5例患者外,所有患者均接受静脉补铁且补铁模式相似。在回顾性队列中,铁蛋白与住院天数和住院频率的相关系数(r均 = +0.39,P < 0.001)高于白蛋白与住院天数(r = -0.31,P = 0.001)和住院频率(r = -0.28,P = 0.005)的相关系数,且在病例组合调整后相关系数仍具有相似的显著性。在前瞻性研究中, 17例死亡患者的血清铁蛋白“死前”值(891±476 ng/mL)高于其“初始”值(619±345 ng/mL,P = 0.007)以及84例存活和退出研究患者的铁蛋白均值(639±358 ng/mL,P = 0.001)。尽管Cox比例风险分析显示仅血清白蛋白对死亡的优势比有显著意义,而铁蛋白无显著意义,但使用死前值的逻辑回归分析证实血清白蛋白降低和血清铁蛋白升高作为透析死亡率标志物均有显著影响。病例组合调整后,血清铁蛋白每增加500 ng/dL的死亡相对风险为2.71(95%置信区间,1.06至7.02),血清白蛋白每降低0.5 g/dL的死亡相对风险为4.48(95%置信区间,1.77至11.33)。因此,血清铁蛋白是透析患者住院的一个强有力的预测指标。尽管血清白蛋白是血液透析患者死亡率的一个强有力的长期标志物,但血清铁蛋白升高似乎是12个月期间死亡更可靠的短期标志物。因此,在统一补铁的情况下,高血清铁蛋白可能是发病风险因素,近期血清铁蛋白升高可能使这些患者的死亡风险增加。