Erzin Yusuf, Uzun Hafize, Celik Aykut Ferhat, Aydin Seval, Dirican Ahmet, Uzunismail Hulya
Department of Gastroenterology, Istanbul University, Cerrahpasa Medical Faculty, Istanbul, Turkey.
J Clin Gastroenterol. 2008 May-Jun;42(5):481-6. doi: 10.1097/MCG.0b013e318046eab0.
Homocysteine is a sulfur-containing amino acid formed during the demethylation of methionine and high levels of this amino acid is a known risk factor for both arterial and also venous thromboembolic complications. Deficiencies of cobalamin, folate, and pyridoxine may predispose subjects to hyperhomocysteinemia, a common phenomenon in inflammatory bowel disease (IBD) patients. The aim of this study was to identify the prevalence, risk factors of hyperhomocysteinemia and its correlation with prior thromboembolic events in an IBD cohort without past intestinal resections.
In this prospective study, we studied the concentrations of homocysteine, cobalamin, folate, and pyridoxine in 105 consecutive patients with IBD, of whom 11 had a prior history of thromboembolic complications. Data regarding smoking habits, medication use, disease location, and severity were gathered and patients with past intestinal resections were excluded. Age-matched and sex-matched 85 healthy volunteers served as controls and multivariate regression analysis was performed to find out independent predictors of hyperhomocysteinemia.
The mean age (+/-SD) in the IBD cohort was 38.69+/-12.13 years, and 51% were male. The mean age in the control group was 37.61+/-10.05 years, and 52% were male. Homocysteine concentrations in patients were higher [16.35 micromol/L (range 6.82 to 48.15) vs. 9.60 micromol/L (range 4.97 to 17.39), P=0.000] and hyperhomocysteinemia had a higher prevalence in patients than in the controls (56.2% vs. 4.7%, chi2=56.179, P=0.000), thus IBD significantly increased the risk of hyperhomocysteinemia [odds ratio=25.973 (95% confidence interval: 8.861-76.128)]. Homocysteine concentrations in patients with a history of thrombosis were not higher than those without a history of thrombosis [16.29 micromol/L (range 8.45 to 34.75) vs. 16.36 micromol/L (range 6.82 to 48.15), not significant]. Hyperhomocysteinemia was found in 54.5% of patients with thrombosis and 56.4% of patients without thrombosis (not significant). On stepwise regression analysis, plasma cobalamin level, albumin concentration, erythrocyte sedimentation rate, and platelet count were found to be independent predictors of elevated homocysteine levels.
IBD patients have a higher prevalence of hyperhomocysteinemia than do healthy controls and elevated homocysteine levels are independently associated with lower serum cobalamin, albumin levels and elevated erythrocyte sedimentation rate, and platelet count. There is no correlation between hyperhomocysteinemia and a history of prior thromboembolic events.
同型半胱氨酸是甲硫氨酸去甲基化过程中形成的含硫氨基酸，这种氨基酸水平升高是动脉和静脉血栓栓塞并发症的已知危险因素。钴胺素、叶酸和吡哆醇缺乏可能使受试者易患高同型半胱氨酸血症，这在炎症性肠病（IBD）患者中是一种常见现象。本研究的目的是确定未行过肠道切除术的IBD队列中高同型半胱氨酸血症的患病率、危险因素及其与既往血栓栓塞事件的相关性。
在这项前瞻性研究中，我们研究了105例连续的IBD患者的同型半胱氨酸、钴胺素、叶酸和吡哆醇浓度，其中11例有血栓栓塞并发症病史。收集了关于吸烟习惯、用药情况、疾病部位和严重程度的数据，并排除了有过肠道切除术的患者。85名年龄和性别匹配的健康志愿者作为对照，进行多因素回归分析以找出高同型半胱氨酸血症的独立预测因素。
IBD队列的平均年龄（±标准差）为38.69±12.13岁，51%为男性。对照组的平均年龄为37.61±10.05岁，52%为男性。患者的同型半胱氨酸浓度更高[16.35微摩尔/升（范围6.82至48.15）对9.60微摩尔/升（范围4.97至17.39），P = 0.000]，患者中高同型半胱氨酸血症的患病率高于对照组（56.2%对4.7%，χ2 = 56.179，P = 0.000），因此IBD显著增加了高同型半胱氨酸血症的风险[比值比=25.973（95%置信区间：8.861 - 76.128）]。有血栓形成病史的患者的同型半胱氨酸浓度并不高于无血栓形成病史的患者[16.29微摩尔/升（范围8.45至34.75）对16.36微摩尔/升（范围6.82至48.15），无显著性差异]。54.5%有血栓形成的患者和56.4%无血栓形成的患者存在高同型半胱氨酸血症（无显著性差异）。在逐步回归分析中，血浆钴胺素水平、白蛋白浓度、红细胞沉降率和血小板计数被发现是同型半胱氨酸水平升高的独立预测因素。
IBD患者高同型半胱氨酸血症的患病率高于健康对照组，同型半胱氨酸水平升高与血清钴胺素水平降低、白蛋白水平降低以及红细胞沉降率和血小板计数升高独立相关。高同型半胱氨酸血症与既往血栓栓塞事件病史之间无相关性。
