Division of Nephrology and Dialysis, Department of Internal Medicine and Medical Specialties, Renal Program, Columbus-Gemelli University Hospital, Catholic University of Rome, Rome, Italy.
J Nephrol. 2011 Jul-Aug;24(4):446-52. doi: 10.5301/JN.2011.8348.
Disordered metabolism of phosphorus is one of the hallmarks of chronic kidney disease (CKD), resulting in increased cardiovascular morbidity and mortality. Age and sex may affect the metabolism of phosphorus and subsequently its serum level. We evaluated if age- and sex-specific cutoffs for hyperphosphatemia may define cardiovascular risk better than the current guideline cutoffs.
We used data from 16,834 subjects participating in the 1999-2006 National Health and Nutrition Examination Survey (NHANES); the prevalence of self-reported cardiovascular disease (CVD) and mortality rates were analyzed in CKD patients for both the classic definitions (CH; i.e., NKF-KDOQI and K-DIGO) and a tailored definition (TH) of hyperphosphatemia by means of regression models adjusted for age, sex, race/ethnicity, smoking status and body mass index. The cutoffs for TH were represented by the 95th percentile of an age- and sex-matched non-CKD population.
Serum phosphorus levels showed an inverse correlation with age (r = -0.12; p<0.001); females showed higher levels than males (3.78 ± 0.54 mg/dL vs. 3.62 ± 0.58 mg/dL; p<0.001). Even if the association between the TH definition and CVD was marginally better compared with the CH definition (odds ratio [OR] = 1.49, 95% confidence interval [95% CI], 1.04-2.13; p=0.030 vs. OR=1.55, 95% CI, 0.98-2.44; p = 0.059), the TH model was not superior in predicting CVD or mortality.
Our data suggest that a tailored, age- and sex-specific definition of hyperphosphatemia is not superior to conventional definitions in predicting cardiovascular events in patients with CKD.
磷代谢紊乱是慢性肾脏病（CKD）的特征之一，导致心血管发病率和死亡率增加。年龄和性别可能会影响磷的代谢，进而影响其血清水平。我们评估了针对高磷血症的年龄和性别特异性切点是否比现行指南切点更能明确心血管风险。
我们使用了 1999-2006 年全国健康和营养调查（NHANES）中 16834 名参与者的数据；通过回归模型，在 CKD 患者中分析了经典定义（CH，即 NKF-KDOQI 和 K-DIGO）和高磷血症的定制定义（TH）下的自我报告心血管疾病（CVD）患病率和死亡率，回归模型调整了年龄、性别、种族/民族、吸烟状况和体重指数。TH 的切点表示与年龄和性别匹配的非 CKD 人群的第 95 百分位。
血清磷水平与年龄呈负相关（r = -0.12；p<0.001）；女性的水平高于男性（3.78 ± 0.54mg/dL 比 3.62 ± 0.58mg/dL；p<0.001）。尽管与 CH 定义相比，TH 定义与 CVD 的相关性略好（比值比[OR] = 1.49，95%置信区间[95%CI]，1.04-2.13；p=0.030 比 OR=1.55，95%CI，0.98-2.44；p = 0.059），但 TH 模型在预测 CVD 或死亡率方面并不占优势。
我们的数据表明，针对高磷血症的定制、年龄和性别特异性定义在预测 CKD 患者的心血管事件方面并不优于传统定义。
