不同剂量叶酸、B族维生素对冠心病患者血浆同型半胱氨酸的影响

目的探讨不同剂量叶酸、B族维生素对冠心病患者血浆同型半胱氨酸(Hcy)水平的影响。方法对90例血浆同型半胱氨酸增高的冠心病患者随机分为A、B、C三组,每组30例,A、B组为治疗组,口服不同剂量的叶酸、B族维生素;C组为对照组,不服用上述药物。治疗前和治疗4周后分别测定血浆同型半胱氨酸的变化。结果A组、B组干预治疗4周后血浆Hcy明显下降,与C组比较P<0.001,A组、B组治疗前后自身比较P<0.001,A、B两组间比较差异无统计学意义(P>0.05)。结论冠心病患者用叶酸、B族维生素干预治疗后,血浆Hcy明显下降。其下降程度与药物剂量无明显关系,小剂量应用可达防治目的,可作为冠心病患者的早期预防药物。     

冠心病人同型半胱氨酸水平的主要影响因素

目的　分析影响冠心病人血浆同型半胱氨酸水平的主要非遗传因素。方法　 16 4例住院冠心病患者 ,测定血浆同型半胱氨酸水平并分析其与血浆及全血叶酸、血浆维生素B12 、血清雌二醇浓度以及冠心病传统危险因素之间的关系。结果　血浆同型半胱氨酸水平与叶酸、维生素B12 水平呈负相关 ,男性血浆同型半胱氨酸浓度高于女性 [(2 0 74± 13 42 )× 10 -6mol/L比 (15 5 6± 8 16 )× 10 -6mol/L ,P <0 0 5 ],吸烟者高于不吸烟者 [(2 2 2 9± 15 18)× 10 -6mol/L比 (17 2 1± 9 5 4)× 10 -6mol/L ,P <0 0 5 ]。结论　叶酸、维生素B12 、性别和吸烟是影响冠心病患者血浆同型半胱氨酸水平的主要非遗传因素     

叶酸、VitB_(12)和VitB_6在冠心病防治中的作用

本文对近年来国内外有关叶酸、Vit B6 、Vit B1 2 在冠心病防治中的作用进行综述 ,其机制主要是通过降低血清同型半胱氨酸的浓度 ,改善了冠心病患者血管内皮功能 ,调节血小板聚集 ,血管张力和血栓形成 ,从而支持了补充 B族维生素能降低心血管疾病危险性的观点     

Role of vitamins B6, B12 and folic acid on hyperhomocysteinemia in a Pakistani population of patients with acute myocardial infarction

BACKGROUND AND AIM: Pakistani people belong to an ethnic group which has the highest rate of coronary artery disease (CAD). We investigated the possible correlation between deficiency of vitamins B6, B12 or folic acid and hyperhomocysteinemia in Pakistani patients with acute myocardial infarction (AMI). A case-control study was carried out involving 224 AMI patients (age 30-70 years; 55 females and 169 males) and 126 normal healthy subjects (age 31-70 years; 35 females and 91 males). METHODS AND RESULTS: Fasting venous blood was obtained from cases and controls. Serum was analyzed for folic acid and B12 using radioassays. Plasma was analyzed for pyridoxal phosphate (PLP; coenzymic form of B6) using a radioenzymatic assay and for total homocysteine using a fluorescence polarization immunoassay. Mean serum B12 concentration in AMI patients was found to be significantly lower than the mean for controls (241+/-185 pg/ml vs 608+/-341 pg/ml; p < 0.001). Mean serum folate level in patients was also found to be lower than controls (3.35+/-3.78 ng/ml vs 4.93+/-2.93 ng/ml), however, the differences were not statistically significant. Similarly, mean PLP concentration in plasma of cases (19.4+/-24.4 nmol/l) was lower than the concentration in controls (23.2+/-17.6 nmol/l), but the difference was not statistically significant. Mean plasma homocysteine level in AMI cases (18+/-8.36 micromol/l) was higher than the mean level in controls (16.4+/-4.9 micromol/l), but not to a significant extent. However, this mean homocysteine concentration in normal healthy subjects was among the highest reported in the literature and was significantly more than mean values reported in most Eastern and Western studies. Compared to controls, there was significantly greater deficiency of folate (32.5% vs 67.1%), B12 (3.2% vs 63.4%) and PLP (49.2% vs 74.1%) in AMI patients. Deficiencies of folate, B12 and PLP were defined as serum folate levels less than 3.5 ng/ml, serum levels of B12 less than 200 pg/ml and plasma PLP levels less than 20 nmol/l. Mean plasma homocysteine levels in smokers were found to be significantly higher in both cases and controls. Similarly, mean serum folate levels in smokers (compared to nonsmokers) were significantly lower in both cases and controls. CONCLUSIONS: Substantial nutritional deficiencies of these three vitamins along with mild hyperhomocysteinemia, perhaps through an interplay with the classical cardiovascular risk factors (highly prevalent in this population), could be further aggravating the risk of CAD in the Pakistani population.     

根治幽门螺杆菌三联疗法对冠心病患者内皮功能的影响

目的：根治探讨幽门螺杆菌（Hp）三联疗法对冠状动脉粥样硬化性心脏病（CHD）患者血管内皮功能的影响。方法纳入2010年10月～2013年2月大庆龙南医院院心内科住院14C尿素呼气试验（14C-UBT）阳性的冠心病患者104例,在常规治疗的基础上,进行根治Hp三联治疗（阿莫西林＋克拉霉素＋兰索拉唑）,疗程为7天,研究期为6个月。研究对象在试验前后检测血脂、血栓素B2（TXB2）和6-酮前列腺素F1α（6-keto-PGF1α）,并通过肱动脉内径变化S1进行内皮依赖性血管舒张功能（FMD）检测。结果治疗后患者的血浆总胆固醇（TC）、TXB2水平比治疗前明显降低[TC：（4.98±1.20） mmol/L vs.（5.43±1.87）mmol/L;TXB2：（240±41）pg/ml vs.（282±66）pg/ml],6-keto-PGF1α、CI明显升高[6-keto-PGF1α：（299±69）pg/ml vs.（217±64）pg/ml;S1：（7.86±0.39）% vs.（4.87±0.26）%）],差异有统计学意义（P＜0.05）。结论根治Hp三联疗法可改善合并Hp感染的冠心病患者血管内皮功能。     

急性冠脉综合征高同型半胱氨酸血症与血叶酸等的关系

目的:测定急性冠脉综合征(ACS)患者中血浆高同型半胱氨酸(Hcy)水平,研究其与血浆叶酸、维生素B12的关系。方法:对52例ACS患者与46例对照组患者的血浆Hcy及叶酸、维生素B12水平进行比较分析。结果:ACS患者血浆Hcy含量明显高于对照组(P<0.01),而血浆叶酸和维生素B12水平明显低于对照组(P<0.01)。两组血浆Hcy含量与叶酸、维生素B12含量呈负相关(r=0.505,0.405,P<0.01)。结论:高Hcy血症通过加速动脉粥样硬化而导致急性冠脉综合征。补充叶酸、维生素B12或许对急性冠脉综合征的防治有益。     

叶酸和维生素B6、B12对不稳定型心绞痛并高同型半胱氨酸患者预后的影响

近年来的研究表明,高同型半胱氨酸（homocys—teine,Hcy）血症可导致心血管疾病发病率和死亡率增高,与高脂血症、高血压、高血糖等因素同等重要,是动脉粥样硬化发生、发展的一个独立危险因素。     

大剂量叶酸对介入治疗后的冠心病患者血管内皮功能的影响

目的探讨大剂量叶酸能否改善冠心病患者介入治疗后的血管内皮功能。方法共46例冠心病患者,在行冠状动脉介入治疗术后分为叶酸治疗(20mg/d)组23例和对照组23例,随访6个月,观察两组间同型半胱氨酸水平,以超声测定肱动脉血流介导的舒张功能(FMD)变化来评价血管内皮功能,并观察两组间的差别。结果大剂量叶酸治疗组血浆同型半胱氨酸水平低于对照组(8·82±3·32μmol/L比12·67±3·07μmol/L,P<0·01)。叶酸治疗后FMD由4·70%±1·71%增加至8·53%±1·44%(P<0·01)。结论大剂量叶酸治疗可能通过降低同型半胱氨酸以外的途径改善血管内皮功能,对介入治疗后的冠心病患者发挥潜在益处。     

Flow-mediated dilation and cardiovascular risk prediction: A systematic review with meta-analysis

Background

Flow-mediated dilation (FMD) is an accepted technique to quantify endothelial function and has shown to have prognostic value for future cardiovascular disease (CVD). The predictive strength of FMD in CVD patients compared to populations not diagnosed for CVD warrants further investigation. We systematically reviewed prospective studies that investigated the association between brachial FMD and future cardiovascular events, with particular focus on the role of underlying health status.

Methods

To obtain eligible studies, several literature databases were systematically searched through March 2011. Pooled overall risk estimates were calculated separately for continuous risk estimates for CVD (per 1% higher FMD) and for categorical risk estimates for CVD (having high vs. low FMD), based on random-effects models.

Results

A total of 23 studies including 14,753 subjects were eligible for inclusion in the meta-analysis. For studies reporting continuous risk estimates, the pooled overall CVD risk was 0.92 (95%CI: 0.88; 0.95) per 1% higher FMD. The observed association seemed stronger (P-value < 0.01) in diseased populations than in asymptomatic populations (0.87 (95%CI: 0.83; 0.92) and 0.96 (95%CI: 0.92; 1.00) per 1% higher FMD, respectively). For studies reporting categorical risk estimates, the pooled overall CVD risk for high vs. low FMD was similar in both types of populations, on average 0.49 (95%CI: 0.39; 0.62).

Conclusions

Our findings show that brachial FMD is inversely associated with future CVD events, with some indications for a stronger relation in diseased populations. Endothelial dysfunction may be considered relevant for classifying subjects in terms of CVD risk.     

Effect of local and remote ischemic preconditioning on endothelial function in young people and healthy or hypertensive elderly people

To verify whether age affects remote preconditioning, we compared healthy young people (mean age = 28.0 years, SD: 7.2), healthy elderly people (age = 69.2 years, SD: 5.0), and hypertensive elderly people (group 3, age = 72.8 years, SD: 3.9). Each group included 10 participants. The flow-mediated-dilation (FMD) was measured after local (same arm) and remote (leg) ischemic preconditioning.Healthy elderly people had the greatest increase of FMD after ischemic preconditioning compared to baseline (173% after local and 181% after remote preconditioning) and young participants the smallest increase (77% after local and 69% after remote preconditioning) while hypertensive elderly had an intermediate increase (P for comparison across groups: 0.347 for local and 0.064 for remote preconditioning). However, absolute values of FMD after preconditioning were much lower in elderly hypertensive than in healthy young adults.Remote preconditioning increases endothelial reactivity in healthy and hypertensive elderly. The potential clinical relevance of this finding deserves consideration.     

The effect of homocysteine-lowering therapy with folic acid on flow-mediated vasodilation in patients with coronary artery disease: A meta-analysis of randomized controlled trials

Objective

High level of homocysteine induces injury of endothelial cells and predicts adverse cardiovascular events. The objective was to assess the effect of homocysteine-lowering therapy with folic acid on flow-mediated vasodilation in patients with coronary artery disease.

Methods and results

We conducted a meta-analysis of randomized controlled trials identified from PubMed, Embase, the Cochrane Library. Eight studies were included. Homocysteine-lowering therapy with folic acid in patients with coronary artery disease significantly improve FMD as compared with placebo using random-effect model (SMD = 1.65 with 95% CI 1.12–2.17, p < 0.001). Subgroup analysis of subjects revealed that lipid-lowering therapy, study duration, and Delphi criteria had no effects on FMD.

Conclusion

Our meta-analysis demonstrated that folic acid supplementation can significantly improve endothelial dysfunction as assessed by FMD in the brachial artery in patients with coronary heart disease.     

叶酸减少心脑血管病风险的新机制

叶酸是同型半胱氨酸代谢中的重要辅助因子,参与叶酸代谢的酶的活性降低是引起高同型半胱氨酸血症的最主要的因素。高同型半胱氨酸血症是心脑血管病的危险因素之一,降低同型半胱氨酸,就能有效地减少心脑血管病风险。叶酸还通过其他机制保护心脑血管。     

非酒精性脂肪性肝病与心血管疾病的相关性分析

目的：探讨非酒精性脂肪性肝病（NAFLD）与心血管疾病（CVD）的关系。方法根据CT检查结果将研究对象分为NAFLD患者（48例）和健康人（43例）,超声测定外周血管硬化和颈动脉内膜中层厚度（IMT）等相关指标,检测生化和内皮舒张功能指标,心脏CTA检测冠状动脉粥样病变。结果 NAFLD患者可溶性细胞间黏附分子-1[sICM-1,（185.1±36.2）ng/ml]、血内皮素-1[ET-1,（104.8±19.3）pg/ml]和臂踝脉搏波速度[baPWV,（15.5±2.3） cm/s]显著高于健康人（85.4±17.3）ng/ml、（67.5±12.1）pg/ml和（13.6±2.4）cm/s,（P＜0.05）,而肱动脉血流介导的内皮依赖性舒张功能[FMD,（8.1±2.4）%]明显低于健康人（13.2±3.5）%,（P＜0.05）;此外,NAFLD患者颈动脉IMT厚度（1.31±0.35）mm、劲动脉（31.3%）和冠状动脉粥样斑块检出率（35.4%）均明显高于对照组（0.76±0.18）mm、9.3%和11.6%,（P＜0.05）;Pearson相关分析显示NAFLD分别与IMT、劲动脉和冠状动脉粥样斑块检出率显著正相关（P＜0.01）。结论 NAFLD与CVD密切相关,NAFLD患者可能存在血管内皮功能障碍,应定期进行IMT和粥样斑块检测。     

福辛普利对老年冠心病患者内皮素-1及血管内皮依赖性舒张功能的影响

目的　通过检测患者的内皮素 1(ET 1)浓度及肱动脉对加压刺激的舒张性反应 ,观察福辛普利对老年冠心病患者ET 1及血管内皮依赖性舒张功能的影响。　方法　选择 4 6例老年冠心病患者及 2 8例健康老年人作对照组 ,测定福辛普利 (5～ 10mg)治疗前后患者血浆ET 1浓度及肱动脉对加压刺激的舒张性反应 ,与治疗后及对照组进行比较。　结果　治疗前冠心病患者ET 1水平〔(117 5± 12 0 )ng/L〕较对照组〔(76 2± 10 8)ng/L〕高 (P <0 0 1) ,肱动脉对加压刺激产生舒张性反应而致内径增加 ,其内径增加率为 (4 2± 2 7) % ,较对照组 (2 2 4± 4 9) %降低 (P <0 0 1) ;经福辛普利治疗 6个月后 ,患者ET 1下降为 (93 5± 9 7)ng/L ,肱动脉内径增加率为 (18 0± 3 0 ) % ,与治疗前比较差异有显著性 (P <0 0 5 )。　结论　福辛普利治疗老年冠心病可降低患者血浆ET 1水平及改善患者的血管内皮依赖性舒张功能。     

对原发性高血压伴缺血性脑卒中患者血浆同型半胱氨酸水平的临床观察

目的 :探讨叶酸、维生素B6、腺苷辅酶维生素B12 对原发性高血压伴缺血性脑卒中患者血浆同型半胱氨酸 (Hcy)水平的影响。方法 :血浆Hcy水平增高的缺血性脑卒中住院患者 70例分为干预组 (n =3 5 )和对照组 (n =3 5 )。干预组口服叶酸10mg/d ,维生素B610mg/d ,腺苷辅酶维生素B12 5 0 0 μg/d 4周。对照组未服用上述药物。入院时及 4周后采用高压液相色谱法 (HPLC)测定血浆Hcy含量。结果 :干预组在实施叶酸、维生素B6、腺苷辅酶维生素B12 干预 4周后 ,血浆Hcy水平下降 ,与对照组相比有显著性差异 (P <0 0 5 )。两组患者 4周前后血浆Hcy水平的变化差值具有极显著性差异 (P <0 0 0 1)。结论 :口服叶酸、维生素B6、腺苷辅酶维生素B12 可使原发性高血压伴缺血性脑卒中患者血浆Hcy水平下降     

帕金森病患者认知障碍与血浆同型半胱氨酸水平的相关性研究

目的研究帕金森病(PD)患者认知障碍与血浆同型半胱氨酸(Hcy)水平的关系。方法选择PD患者90例.其中认知功能正常43例(认知正常组).伴认知功能障碍47例(认知障碍组)及健康体检者40例(对照组),比较3组血浆Hcy、叶酸、维生素B_(12)水平。结果认知正常组和认知障碍组患者血浆Hcy水平明显高于对照组[(1 5.70±4.38)μmol/L vs(1 6.20±5.53)μmol/L vs(1 3.51±3.59)μmol/L,P<0.05]。结论 Hcy水平可能与PD认知障碍无关。