Abstract：
OBJECTIVE: The role of urea cycle related amino acids in the development of ischemic stroke (IS) remains unclear. The study aimed to evaluate the association of these amino acids with IS.
METHODS: We conducted a case-control study nested within a cohort study in Changshu, Eastern China. A total of 321 cases and 321 controls matched by age and gender were finally included. Plasma levels of ornithine, arginine, spermidine, and proline were measured using ultra-high performance liquid chromatography-tandem mass-spectrometry (UHPLC-MS/MS). Odds ratios (ORs) and their 95 % confidence intervals (CIs) were calculated by conditional logistic regression analyses.
RESULTS: Plasma ornithine was inversely associated with risk of IS [crude OR: 0.62 (95 % CI: 0.40-0.97)]. After adjustment for body mass index, smoking, hypertension, family history of stroke, estimated glomerular filtration rate, and total cholesterol, the corresponding ORs for the highest compared to the lowest quartiles was essentially unchanged [adjusted OR: 0.62 (95 % CI: 0.39-0.99)]. The risk association remained significant after repeating the analyses by excluding the first two years of follow-up. Plasma arginine, spermidine, and proline were not associated with the risk of IS.
CONCLUSIONS: We observed that higher plasma levels of ornithine were associated with a lower risk of incident IS. Our novel findings suggest a protective role of ornithine in the pathogenesis of IS.
METHODS: We conducted a case-control study nested within a cohort study in Changshu, Eastern China. A total of 321 cases and 321 controls matched by age and gender were finally included. Plasma levels of ornithine, arginine, spermidine, and proline were measured using ultra-high performance liquid chromatography-tandem mass-spectrometry (UHPLC-MS/MS). Odds ratios (ORs) and their 95 % confidence intervals (CIs) were calculated by conditional logistic regression analyses.
RESULTS: Plasma ornithine was inversely associated with risk of IS [crude OR: 0.62 (95 % CI: 0.40-0.97)]. After adjustment for body mass index, smoking, hypertension, family history of stroke, estimated glomerular filtration rate, and total cholesterol, the corresponding ORs for the highest compared to the lowest quartiles was essentially unchanged [adjusted OR: 0.62 (95 % CI: 0.39-0.99)]. The risk association remained significant after repeating the analyses by excluding the first two years of follow-up. Plasma arginine, spermidine, and proline were not associated with the risk of IS.
CONCLUSIONS: We observed that higher plasma levels of ornithine were associated with a lower risk of incident IS. Our novel findings suggest a protective role of ornithine in the pathogenesis of IS.
摘要：
目的：尿素循环相关氨基酸在缺血性卒中（IS）发展中的作用尚不清楚。该研究旨在评估这些氨基酸与IS的关联。
方法：我们在常熟的一项队列研究中进行了一项病例对照研究，中国东部。最终纳入321例病例和321名年龄和性别相匹配的对照。鸟氨酸的血浆水平,精氨酸亚精胺,采用超高效液相色谱-串联质谱(UHPLC-MS/MS)检测脯氨酸含量。通过条件逻辑回归分析计算赔率（OR）及其95％置信区间（CI）。
结果：血浆鸟氨酸与IS风险呈负相关[粗OR：0.62（95％CI：0.40-0.97）]。调整体重指数后，吸烟,高血压,中风家族史,估计肾小球滤过率，和总胆固醇，与最低四分位数相比,最高四分位数的相应OR基本没有变化[调整后OR:0.62(95%CI:0.39~0.99)].通过排除前两年的随访重复分析后，风险关联仍然显著。血浆精氨酸，亚精胺,和脯氨酸与IS的风险无关。
结论：我们观察到较高的鸟氨酸血浆水平与较低的IS事件风险相关。我们的新发现表明鸟氨酸在IS的发病机理中具有保护作用。
方法：我们在常熟的一项队列研究中进行了一项病例对照研究，中国东部。最终纳入321例病例和321名年龄和性别相匹配的对照。鸟氨酸的血浆水平,精氨酸亚精胺,采用超高效液相色谱-串联质谱(UHPLC-MS/MS)检测脯氨酸含量。通过条件逻辑回归分析计算赔率（OR）及其95％置信区间（CI）。
结果：血浆鸟氨酸与IS风险呈负相关[粗OR：0.62（95％CI：0.40-0.97）]。调整体重指数后，吸烟,高血压,中风家族史,估计肾小球滤过率，和总胆固醇，与最低四分位数相比,最高四分位数的相应OR基本没有变化[调整后OR:0.62(95%CI:0.39~0.99)].通过排除前两年的随访重复分析后，风险关联仍然显著。血浆精氨酸，亚精胺,和脯氨酸与IS的风险无关。
结论：我们观察到较高的鸟氨酸血浆水平与较低的IS事件风险相关。我们的新发现表明鸟氨酸在IS的发病机理中具有保护作用。
