Sheffield Kidney Institute, Sheffield, UK.
Department of Infection, Immunity and Cardiovascular Disease, University of Sheffield, Medical School, Royal Hallamshire Hospital, Sheffield, UK.
Nephrol Dial Transplant. 2018 Apr 1;33(4):607-613. doi: 10.1093/ndt/gfx081.
Obesity is associated with albuminuria and incident kidney disease. Increased vulnerability of the glomerular microcirculation to elevated systemic blood pressure is postulated to contribute to adverse effects of obesity on the kidney. We therefore hypothesized that obesity would modulate the association between systolic blood pressure (sBP) and albuminuria.
The relationship between obesity and albuminuria [fractional albumin excretion (FEalb) or albumin:creatinine ratio (ACR)] was modelled using linear/logistic regression in the US National Health and Nutrition Examination Survey 1999-2010 cohorts (N = 23 710). Associations between sBP and albuminuria were examined across strata of waist circumference and body mass index (BMI) using interaction terms.
Obesity was associated with albuminuria through an interaction with sBP. Among participants in the 4th/5th quintiles of waist circumference each 10 mmHg increase in sBP was accompanied by approximately double the increment in FEalb observed among those in quintile 2 (14% versus 7%, P < 0.001). There was also evidence of a lower sBP threshold for the relationship between sBP and albuminuria in obesity. While FEalb increased with sBP >110 mmHg in quintile 5 of waist circumference, in quintile 2 FEalb did not increase until sBP was >130 mmHg. Findings were consistent when defining obesity by BMI or waist circumference and when quantifying albuminuria by ACR or FEalb. Assessing albuminuria as the odds ratio of ACR >30 mg/g also gave similar results.
The interaction between sBP and obesity supports the premise that obesity sensitizes the kidney to increased systemic blood pressure.
肥胖与白蛋白尿和肾脏疾病的发生有关。肾小球微循环对升高的系统性血压更敏感，这被认为是肥胖对肾脏产生不利影响的原因之一。因此，我们假设肥胖会调节收缩压（sBP）与白蛋白尿之间的关系。
在美国国家健康和营养检查调查 1999-2010 年队列研究（N=23710）中，采用线性/逻辑回归模型来研究肥胖与白蛋白尿（尿白蛋白排泄率[FEalb]或白蛋白/肌酐比[ACR]）之间的关系。使用交互项来检验 sBP 与白蛋白尿在腰围和体重指数（BMI）各五分位组之间的关系。
肥胖通过与 sBP 的相互作用与白蛋白尿相关。在腰围第 4/5 五分位组的参与者中，每增加 10mmHg 的 sBP，FEalb 的增加量大约是第 2 五分位组的两倍（14%比 7%，P<0.001）。肥胖者的 sBP 与白蛋白尿之间的关系还存在一个较低的 sBP 阈值。在腰围第 5 五分位组中，当 sBP 超过 110mmHg 时，FEalb 增加，但在腰围第 2 五分位组中，只有当 sBP 超过 130mmHg 时，FEalb 才会增加。当用 BMI 或腰围定义肥胖，用 ACR 或 FEalb 定量白蛋白尿时，结果是一致的。用 ACR>30mg/g 评估白蛋白尿，得到的比值比也给出了类似的结果。
sBP 与肥胖之间的相互作用支持这样一个前提，即肥胖使肾脏对升高的系统性血压更为敏感。
