Menon Vandana, Greene Tom, Pereira Arema A, Wang Xuelei, Beck Gerald J, Kusek John W, Collins Alan J, Levey Andrew S, Sarnak Mark J
Division of Nephrology, Department of Medicine, Tufts-New England Medical Center, Boston, MA, USA.
Am J Kidney Dis. 2005 Sep;46(3):455-63. doi: 10.1053/j.ajkd.2005.05.025.
Abnormalities of mineral metabolism are prevalent in patients with kidney failure and are associated with increased risk for cardiovascular events. There are limited data investigating relationships of phosphorus and calcium-phosphorus product with outcomes in patients with chronic kidney disease (CKD) stages 3 to 4.
Serum phosphorus and calcium were measured at baseline in 840 participants from the randomized cohort of the Modification of Diet in Renal Disease Study. Survival status until December 31, 2000, was obtained from the National Death Index. Cox models were performed to assess the relationship of serum phosphorus level and calcium-phosphorus product with all-cause and cardiovascular disease (CVD) mortality.
Mean serum phosphorus level was 3.8 +/- 0.7 mg/dL (1.23 +/- 0.23 mmol/L), calcium-phosphorus product was 34.7 +/- 6.3 mg2/dL2, and glomerular filtration rate (GFR) was 33 +/- 12 mL/min/1.73 m2 (0.55 +/- 0.20 mL/s/1.73 m2). All-cause and CVD mortality rates were 25% and 15%. Serum phosphorus level was not related to all-cause mortality in multivariable models (P = 0.46). In unadjusted analysis, serum phosphorus level was associated with (hazard ratio [HR] per 1 mg/dL increase, 1.34; 95% confidence interval [CI], 1.05 to 1.71; P = 0.02) increased risk for CVD mortality, but this association was partly attenuated and not statistically significant after adjustment for GFR and other confounders (HR, 1.27; 95% CI, 0.94 to 1.73; P = 0.12). Calcium-phosphorus product was not associated with all-cause mortality in unadjusted (P = 0.23) or multivariate analysis (P = 0.35). Calcium-phosphorus product was related to CVD mortality in unadjusted (HR per 10 mg2/dL2 increase, 1.30; 95% CI, 1.01 to 1.69; P = 0.04) analysis, but this association was not statistically significant after adjustment for GFR and other confounders (HR, 1.22; 95% CI, 0.89 to 1.66; P = 0.23).
In the Modification of Diet in Renal Disease Study cohort, serum phosphorus level and calcium-phosphorus product were not statistically associated with all-cause or CVD mortality after adjustment for GFR; however larger studies with additional statistical power are needed to evaluate these relationships, especially in the context of current practice patterns in patients with CKD.
矿物质代谢异常在肾衰竭患者中普遍存在，并且与心血管事件风险增加相关。关于慢性肾脏病（CKD）3至4期患者中磷及钙磷乘积与预后关系的研究数据有限。
在肾病饮食改良研究的随机队列中的840名参与者基线时测定血清磷和钙。从国家死亡指数获取截至2000年12月31日的生存状态。采用Cox模型评估血清磷水平和钙磷乘积与全因死亡率及心血管疾病（CVD）死亡率的关系。
血清磷平均水平为3.8±0.7mg/dL（1.23±0.23mmol/L），钙磷乘积为34.7±6.3mg²/dL²，肾小球滤过率（GFR）为33±12mL/min/1.73m²（0.55±0.20mL/s/1.73m²）。全因死亡率和CVD死亡率分别为25%和15%。在多变量模型中，血清磷水平与全因死亡率无关（P = 0.46）。在未校正分析中，血清磷水平与CVD死亡率风险增加相关（每增加1mg/dL的风险比[HR]为1.34；95%置信区间[CI]为1.05至1.71；P = 0.02），但在调整GFR和其他混杂因素后，这种关联部分减弱且无统计学意义（HR为1.27；95%CI为0.94至1.73；P = 0.12）。钙磷乘积在未校正（P = 0.23）或多变量分析（P = 0.35）中与全因死亡率无关。在未校正分析中钙磷乘积与CVD死亡率相关（每增加10mg²/dL²的HR为1.30；95%CI为1.01至1.69；P = 0.04），但在调整GFR和其他混杂因素后这种关联无统计学意义（HR为1.22；95%CI为0.89至1.66；P = 0.23）。
在肾病饮食改良研究队列中，调整GFR后，血清磷水平和钙磷乘积与全因或CVD死亡率无统计学关联；然而，需要更大规模且具有更大统计学效力的研究来评估这些关系，尤其是在CKD患者当前实际治疗模式的背景下。
