Hernández C, Chacón P, Martí R, García-Pascual L, Mesa J, Simó R
Department of Endocrinology, Hospital General Vall d'Hebron, Barcelona, Spain.
Nephron. 2000 May;85(1):27-33. doi: 10.1159/000045626.
BACKGROUND/AIM: The possible association between lipoprotein(a) [Lp(a)] and albumin excretion rate (AER) is a topic that has generated conflicting views. The aim of this study was to determine the relationship between serum Lp(a) concentrations and AER in diabetic patients, taking into account Lp(a) phenotypes in a multivariate analysis.
For this purpose 191 consecutive diabetic patients (69 type 1 and 122 type 2) were included in the study. Lp(a) was determined by ELISA and its phenotypes by SDS-PAGE followed by immunoblotting. Lp(a) phenotypes were grouped by size in small (F, B, S1, S2), big (S3, S4) and null.
Diabetic patients with an AER >20 microg/min presented higher Lp(a) concentrations than patients with an AER <20 microg/min: median 19 mg/dl versus 5 mg/dl (p < 0.0001). The differences remained at a significant level when the type of diabetes was considered. A linear correlation was observed between Lp(a) concentration and AER (type 1: r = 0.32, p = 0.01; type 2: r = 0.25, p < 0.05). The AER was independently correlated with Lp(a) concentrations in a multiple regression analysis (p < 0.01), and Lp(a) was independently associated with the presence of diabetic nephropathy in the logistic regression analysis. The overall frequency distribution of Lp(a) phenotypes differed significantly between patients with or without microalbuminuria (p < 0.05). In addition, the AER (microg/min) was different among the Lp(a) phenotypes: small 55 +/- 122 (median 4.9), big 58 +/- 123 (median 5.7) and null 3 +/- 2 (median 2.3); p = 0.01. The significant difference mainly resulted from low AER (<10 microg/min) detected in all patients with the null phenotype.
In diabetic patients the serum Lp(a) concentration is associated with AER. Thus, the elevated cardiovascular risk observed in diabetic patients with a high AER could be related to the Lp(a) concentration. Finally, patients with the null Lp(a) phenotype can be considered as a group at low risk of the development of diabetic nephropathy.
背景/目的：脂蛋白(a)[Lp(a)]与白蛋白排泄率(AER)之间可能存在的关联是一个引发了不同观点的话题。本研究的目的是在多变量分析中考虑Lp(a)表型，以确定糖尿病患者血清Lp(a)浓度与AER之间的关系。
为此，本研究纳入了191例连续的糖尿病患者(69例1型糖尿病患者和122例2型糖尿病患者)。采用酶联免疫吸附测定法(ELISA)测定Lp(a)，并通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(SDS-PAGE)及免疫印迹法确定其表型。Lp(a)表型按大小分为小(Lp(a)F、Lp(a)B、Lp(a)S1、Lp(a)S2)、大(Lp(a)S3、Lp(a)S4)和无Lp(a)三种类型。
AER>20μg/min的糖尿病患者的Lp(a)浓度高于AER<20μg/min的患者：中位数分别为19mg/dl和5mg/dl(p<0.0001)。考虑糖尿病类型时，差异仍具有显著性。观察到Lp(a)浓度与AER之间存在线性相关性(1型糖尿病：r=0.32，p=0.01；2型糖尿病：r=0.25，p<0.05)。在多元回归分析中，AER与Lp(a)浓度独立相关(p<0.01)，在逻辑回归分析中，Lp(a)与糖尿病肾病的存在独立相关。有或无微白蛋白尿的患者之间，Lp(a)表型的总体频率分布存在显著差异(p<0.05)。此外，不同Lp(a)表型的AER(μg/min)也有所不同：小表型为55±122(中位数4.9)，大表型为58±123(中位数5.7)，无Lp(a)表型为3±2(中位数2.3)；p=0.01。显著差异主要源于所有无Lp(a)表型患者的低AER(<10μg/min)。
在糖尿病患者中，血清Lp(a)浓度与AER相关。因此，AER高的糖尿病患者中观察到的心血管风险升高可能与Lp(a)浓度有关。最后，无Lp(a)表型的患者可被视为糖尿病肾病发生风险低的群体。
