Department of Nephrology and Dialysis, Academic Teaching Hospital, Feldkirch, Austria.
Clin J Am Soc Nephrol. 2011 Nov;6(11):2650-6. doi: 10.2215/CJN.03780411. Epub 2011 Sep 8.
Hypoalbuminemia and hyperphosphatemia have been shown to be strong predictors of mortality in dialysis patients that might not be independent from each other. We prospectively investigated the relationship and interaction between serum albumin and phosphorus with all-cause mortality in an inception cohort of incident dialysis patients.
DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We followed 235 incident dialysis patients in a prospective single-center cohort study (INVOR study) applying a time-dependent Cox proportional hazards model using all measured laboratory values (2887 albumin and 10306 phosphorus values).
Eighty-two patients (35%) died during a median follow-up of 35.1 months. Albumin was inversely associated with mortality (hazard ratio [95% confidence interval]: 0.23 [0.14 to 0.36]; P < 0.001), whereas higher phosphorus concentrations showed a trend to an increasing risk for mortality (hazard ratio 1.57 [95% confidence interval 0.97 to 2.54]; P = 0.07). Importantly, we observed a significant interaction between albumin and phosphorus (P = 0.01). The lowest risk was found with concurrent low phosphorus and high albumin values, whereas risk was increased with either concurrent low phosphorus and low albumin values or high phosphorus and high albumin values.
In incident dialysis patients the associations of serum phosphorus and albumin concentrations with mortality are modified by each other over time. Phosphorus-lowering interventions that concomitantly can cause a fall in serum albumin level may be harmful and warrant additional studies. If confirmed, epidemiologic studies and therapeutic guidelines aiming for target values should consider this interplay.
低白蛋白血症和高磷血症已被证明是透析患者死亡的强有力预测因素，且两者之间可能并非相互独立。我们前瞻性地研究了血清白蛋白和磷与全因死亡率之间的关系和相互作用，纳入了一个起始透析患者的队列研究。
设计、设置、参与者和测量：我们在一项前瞻性的单中心队列研究（INVOR 研究）中对 235 例起始透析患者进行了随访，该研究使用时间依赖性 Cox 比例风险模型，使用所有测量的实验室值（2887 个白蛋白值和 10306 个磷值）。
82 例患者（35%）在中位随访 35.1 个月时死亡。白蛋白与死亡率呈负相关（风险比[95%置信区间]：0.23[0.14 至 0.36]；P<0.001），而较高的磷浓度则显示出死亡风险增加的趋势（风险比 1.57[95%置信区间 0.97 至 2.54]；P=0.07）。重要的是，我们观察到白蛋白和磷之间存在显著的相互作用（P=0.01）。同时存在低磷和高白蛋白值的风险最低，而同时存在低磷和低白蛋白值或高磷和高白蛋白值的风险则增加。
在起始透析患者中，血清磷和白蛋白浓度与死亡率的关联随时间相互影响。同时降低磷水平且可能导致血清白蛋白水平下降的干预措施可能有害，需要进一步研究。如果得到证实，旨在确定目标值的流行病学研究和治疗指南应考虑到这种相互作用。
