Foley R N, Parfrey P S, Harnett J D, Kent G M, Hu L, O'Dea R, Murray D C, Barre P E
Division of Nephrology, Memorial University, St. John's, Nfld, Canada.
Am J Nephrol. 1996;16(5):386-93. doi: 10.1159/000169030.
Hypocalcemia and hyperphosphatemia with secondary hyper-parathyroidism are characteristic of end-stage renal disease (ESRD). Although calcium levels critically affect almost all cellular processes, the impact of chronic hypocalcemia and other abnormalities of calcium-phosphate homeostasis on the prognosis of ESRD patients is unknown.
An inception cohort of 433 patients starting ESRD therapy was followed prospectively for an average of 41 months. Serum calcium and other parameters were measured monthly. The mean calcium levels were 9.4 +/- 0.7 mg/dl. 23% of the patients had mean calcium levels < 8.8 mg/dl. After adjusting for baseline age, diabetes mellitus, ischemic heart disease, smoking and cholesterol levels, as well as serial albumin, hemoglobin, mean arterial blood pressure, phosphate and alkaline phosphatase levels, chronic hypocalcemia was strongly associated with mortality (RR 2.10, p = 0.006 for a mean calcium level < 8.8 mg/dl). The association with mortality was similar in hemodialysis (RR 2.10, p = 0.006) and peritoneal dialysis patients (2.67, p = 0.034). Using similar covariate adjustment, chronic hypocalcemia was associated with de novo ischemic heart disease (RR 5.23, p < 0.001), recurrent ischemic heart disease (RR 2.46, p = 0.006), de novo cardiac failure (RR 2.64, p < 0.001), and recurrent cardiac failure (RR 3.30, p < 0.001). Hypocalcemia retained its independent impact on morbidity and mortality when analyzed as a time-dependent covariate.
Chronic hypocalcemia, a very common, reversible feature of chronic uremia, is independently associated with morbidity and mortality in ESRD patients.
低钙血症、高磷血症伴继发性甲状旁腺功能亢进是终末期肾病（ESRD）的特征。尽管钙水平对几乎所有细胞过程都有至关重要的影响，但慢性低钙血症及钙磷稳态的其他异常对ESRD患者预后的影响尚不清楚。
对433例开始接受ESRD治疗的初治队列患者进行了平均41个月的前瞻性随访。每月测量血清钙及其他参数。平均钙水平为9.4±0.7mg/dl。23%的患者平均钙水平<8.8mg/dl。在对基线年龄、糖尿病、缺血性心脏病、吸烟和胆固醇水平，以及连续的白蛋白、血红蛋白、平均动脉血压、磷和碱性磷酸酶水平进行校正后，慢性低钙血症与死亡率密切相关（平均钙水平<8.8mg/dl时，相对危险度为2.10，p = 0.006）。血液透析患者（相对危险度为2.10，p = 0.006）和腹膜透析患者（相对危险度为2.67，p = 0.034）中，低钙血症与死亡率的关联相似。采用类似的协变量校正后，慢性低钙血症与新发缺血性心脏病（相对危险度为5.23，p<0.001）、复发性缺血性心脏病（相对危险度为2.46，p = 0.006）、新发心力衰竭（相对危险度为2.64，p<0.001）和复发性心力衰竭（相对危险度为3.30，p<0.001）相关。当作为时间依赖性协变量进行分析时，低钙血症对发病率和死亡率仍具有独立影响。
慢性低钙血症是慢性尿毒症非常常见的可逆特征，与ESRD患者的发病率和死亡率独立相关。
