Norman Paul E, Davis Wendy A, Coughlan Melinda T, Forbes Josephine M, Golledge Jonathan, Davis Timothy M E
School of Surgery, University of Western Australia, Freemantle, Australia.
J Vasc Surg. 2009 Sep;50(3):626-31. doi: 10.1016/j.jvs.2009.05.058. Epub 2009 Jul 22.
Abdominal aortic aneurysms (AAAs) share common risk factors with atherosclerosis, except for diabetes which appears protective. The reason for this is unknown. Although increased circulating concentrations of advanced glycation endproducts (AGEs) such as carboxymethyllysine (CML) are associated with occlusive vascular disease, it is possible that their effects on the aortic wall explain the paradoxically low incidence of AAAs in diabetes.
We studied 234 community-dwelling men aged 65 to 79 years. The cases comprised all identifiable diabetic men with AAA (aortic diameter > or =30 mm on ultrasound; n = 27) and randomly-selected non-diabetic men with AAA (n = 67). Controls were age-matched randomly-selected diabetic men (n = 69) and age-matched randomly-selected non-diabetic men (n = 71) without AAA (aortic diameter 18 to 22 mm). Serum CML concentrations were measured by validated indirect enzyme-linked immunosorbent assay (ELISA).
Serum CML concentrations were significantly lower in men with AAAs than those without (6627 +/- 1544 vs 7309 +/- 1490 nmol/mol lysine; P = .001). Variables positively associated with AAA were height, diastolic blood pressure, smoking, a history of coronary heart disease, and serum creatinine (P < or = .040), while serum CML (odds ratio [95% confidence interval] per 1000 nmol/mol lysine; 0.80 [0.64-0.98]) and a history of diabetes were inversely associated (P < or = .040). After adjusting, the interaction between diabetes status and serum CML was negatively associated with AAA (P = .016).
These cross-sectional data show that circulating concentrations of CML are reduced in diabetic men with AAAs. This is in contrast to studies of the relationship between AGEs and occlusive manifestations of cardiovascular disease and could explain the inverse association between diabetes and AAA.
腹主动脉瘤（AAA）与动脉粥样硬化有共同的危险因素，但糖尿病似乎具有保护作用。其原因尚不清楚。尽管循环中晚期糖基化终产物（AGEs）如羧甲基赖氨酸（CML）浓度升高与闭塞性血管疾病有关，但它们对主动脉壁的影响可能解释了糖尿病患者中AAA发病率异常低的现象。
我们研究了234名年龄在65至79岁的社区男性。病例包括所有可识别的患有AAA的糖尿病男性（超声检查主动脉直径≥30 mm；n = 27）和随机选择的患有AAA的非糖尿病男性（n = 67）。对照组是年龄匹配的随机选择的无AAA的糖尿病男性（n = 69）和年龄匹配的随机选择的无AAA的非糖尿病男性（n = 71）（主动脉直径18至22 mm）。通过经过验证的间接酶联免疫吸附测定（ELISA）测量血清CML浓度。
患有AAA的男性血清CML浓度显著低于未患AAA的男性（6627±1544对7309±1490 nmol/mol赖氨酸；P = 0.001）。与AAA呈正相关的变量有身高、舒张压、吸烟、冠心病史和血清肌酐（P≤0.040），而血清CML（每1000 nmol/mol赖氨酸的优势比[95%置信区间]；0.80[0.64 - 0.98]）和糖尿病史呈负相关（P≤0.040）。调整后，糖尿病状态与血清CML之间的相互作用与AAA呈负相关（P = 0.016）。
这些横断面数据表明，患有AAA的糖尿病男性循环中CML浓度降低。这与AGEs与心血管疾病闭塞表现之间关系的研究结果相反，并且可以解释糖尿病与AAA之间的负相关关系。
