Phoenix Epidemiology and Clinical Research Branch, Phoenix, AZ, USA.
Am J Nephrol. 2017;46(4):276-284. doi: 10.1159/000481269. Epub 2017 Sep 22.
Serum amyloid A (SAA) induces inflammation and apoptosis in kidney cells and is found to be causing the pathologic changes that are associated with diabetic kidney disease (DKD). Higher serum SAA concentrations were previously associated with increased risk of end-stage renal disease (ESRD) and death in persons with type 2 diabetes and advanced DKD. We explored the prognostic value of SAA in American Indians with type 2 diabetes without DKD or with early DKD.
SAA concentration was measured in serum samples obtained at the start of follow-up. Multivariate proportional hazards models were employed to examine the magnitude of the risk of ESRD or death across tertiles of SAA concentration after adjustment for traditional risk factors. The C statistic was used to assess the additional predictive value of SAA relative to traditional risk factors.
Of 256 participants (mean ± SD glomerular filtration rate [iothalamate] = 148 ± 45 mL/min, and median [interquartile range] urine albumin/creatinine = 39 [14-221] mg/g), 76 developed ESRD and 125 died during a median follow-up period of 15.2 and 15.7 years, respectively. After multivariable proportional hazards regression, participants in the 2 highest SAA tertiles together exhibited a 53% lower risk of ESRD (hazard ratio [HR] 0.47, 95% CI 0.29-0.78), and a 30% lower risk of death (HR 0.70, 95% CI 0.48-1.02), compared with participants in the lowest SAA tertile, although the lower risk of death was not statistically significant. Addition of SAA to the ESRD model increased the C statistic from 0.814 to 0.815 (p = 0.005).
Higher circulating SAA concentration is associated with a reduced risk of ESRD in American Indians with type 2 diabetes.
血清淀粉样蛋白 A（SAA）可诱导肾细胞炎症和凋亡，并导致与糖尿病肾病（DKD）相关的病理变化。先前的研究表明，血清 SAA 浓度较高与 2 型糖尿病和晚期 DKD 患者终末期肾病（ESRD）和死亡风险增加相关。我们探讨了 SAA 在无 DKD 或早期 DKD 的 2 型糖尿病美国印第安人中的预后价值。
在随访开始时测量血清样本中的 SAA 浓度。采用多变量比例风险模型，在校正传统危险因素后，研究 SAA 浓度三分位数与 ESRD 或死亡风险之间的关系。C 统计量用于评估 SAA 相对于传统危险因素的额外预测价值。
在 256 名参与者（平均肾小球滤过率[碘海醇]±SD=148±45mL/min，中位数[四分位间距]尿白蛋白/肌酐=39[14-221]mg/g）中，76 名参与者发展为 ESRD，125 名参与者在中位随访 15.2 和 15.7 年后死亡。多变量比例风险回归后，最高两个 SAA 三分位数组的参与者 ESRD 风险降低了 53%（风险比[HR]0.47，95%可信区间[CI]0.29-0.78），死亡风险降低了 30%（HR 0.70，95%CI 0.48-1.02），与最低 SAA 三分位数组的参与者相比，尽管死亡风险降低无统计学意义。将 SAA 添加到 ESRD 模型中，C 统计量从 0.814 增加到 0.815（p=0.005）。
在 2 型糖尿病的美国印第安人中，较高的循环 SAA 浓度与 ESRD 风险降低相关。
