同型半胱氨酸、叶酸和维生素B12与精神分裂症的关系

目的 探讨精神分裂症患者血浆同型半胱氨酸、血清叶酸和维牛素B12水平的改变及其可能的意义.方法 采用病例对照研究,精神分裂症患者组122例,正常对照组122例.循环酶法测定两组血浆同型半胱氨酸水平;电化学发光仪测定叶酸和维生素B12水平.结果 ①精神分裂症患者组血浆间型半胱氨酸水平[(27.23±21.41)I.Lmob/L]明显高于正常对照组[(14.34±7.45)tunol/L],差异有统计学意义(P<0.001);②精神分裂症患者组维牛素B12水平[(328.93±157.52)pg/mL]明显低于正常对照组[(464.02±166.29)pg/mL],差异有统计学意义(P<0.05);③血浆同型半胱氩酸水平与叶酸水平(r=-0.44,P<0.001)和维生素Bi2水平(r=-0.36,P<0.001)均呈负相关;④Ligistic回归分析结果 显示,同型半胱氨酸与精神分裂症有关(P<0.001),其优势比(OR)为1.14(95%CI:1.08-1.21).结论 血浆同型半胱氨酸水平增高可能是精神分裂症的危险因素;叶酸和维生素B12缺乏与精神分裂症患者血浆同型半胱氨酸水平增高有关.     

血清同型半胱氨酸水平与颈动脉粥样硬化的关系及干预后的变化

目的探讨血清同型半胱氨酸(Hcy)水平与颈动脉粥样硬化(CAA)的关系,及叶酸、维生素B12干预后的变化。方法测定169例脑梗死患者(脑梗死组)及110名正常对照者(正常对照组)血清Hcy、叶酸、维生素B12水平;应用彩色多谱勒显像仪对脑梗死患者颈动脉进行检测;分析血清Hcy与叶酸、维生素B12水平以及与CAA程度的关系;观察叶酸、维生素B12干预4周后伴有高Hcy血症的脑梗死患者血清Hcy水平的变化。结果与正常对照组比较,脑梗死组血清Hcy水平明显增高(P<0.01);随着CAA程度增加,血清Hcy水平增高,叶酸、维生素B12水平下降;血清Hcy水平与叶酸、维生素B12水平呈负相关(r=-0.31,P<0.05;r=-0.47,P<0.01),与CAA程度呈正相关(r=0.58,P<0.05);干预治疗后血清Hcy水平显著下降(P<0.01)。结论血清Hcy水平增高是CAA危险因素之一;补充叶酸、维生素B12可降低血清Hcy水平。     

高同型半胱氨酸血症与颅内外血管狭窄的相关性研究

目的 探讨缺血性脑血管病患者高同型半胱氨酸(Hcy)血症与颅内外血管狭窄的关系.方法 应用全自动生化分析仪,用循环酶法检测405例缺血性脑血管病患者血清Hcy水平,同时检测血清叶酸、维生素B12水平,应用经颅多普勒(TCD)检测所有患者的颅内血管,应用双功能彩色多普勒检测颅外血管.根据检测结果将颈内动脉(ICA)分为:正常、轻度狭窄(＜50%)、中度狭窄(50%～69%)、重度狭窄(70%～99%)、闭塞;大脑中动脉(MCA)分为:正常、中度狭窄(50%～69%)、重度狭窄(70%～95%)、极度狭窄(＞95%).结果 有颅内外血管狭窄组血清Hcy水平显著高于无颅内外血管狭窄组(P<0.01),血清叶酸水平显著低于无颅内外血管狭窄组(P<0.05),血清维生素B12水平两组间差异无统计学意义(P>0.05);ICA、MCA不同程度狭窄患者间血清Hcy水平差异有统计学意义(均P<0.01),血清叶酸水平差异有统计学意义(均P<0.05),维生素B12水平差异无统计学意义(均P>0.05);Hcy水平与ICA、MCA狭窄程度呈正相关(r=0.356 ,P<0.01;r=0.345 ,P<0.01);血清叶酸水平与ICA、MCA狭窄程度呈负相关(r=-0.272 ,P<0.05;r=-0.265,P<0.05).结论 高Hcy血症与颅内外血管狭窄程度密切相关,高Hcy血症可能是缺血性脑血管病新的危险因素.     

MTHFR基因多态性在高同型半胱氨酸 血症患者中的分布特点

目的 了解高同型半胱氨酸血症患者中MTHFR基因多态性的分布特点。方法 筛选本院住院患者中高同型半胱氨酸血症患者213例,同时检测亚甲基四氢叶酸还原酶(MTHFR)的C677T位点及血清叶酸及维生素B12水平,根据相关基因酶活性分为高代谢(CC)、中等代谢(CT)、低代谢(TT)。结果(1)高同型半胱氨酸血症患者中CC发生率为24.4%、CT发生率为30.1%、TT发生率为45.5%;(2)高同型半胱氨酸血症患者中叶酸水平降低发生率为12.2%、维生素B12水平降低发生率为8.4%、二者同时水平降低发生率为7.0%。结论 高同型半胱氨酸血症患者中低代谢发生率高,同时多合并叶酸和/或维生素B12水平降低。     

脑梗死患者血浆硫化氢、同型半胱氨酸、叶酸和维生素B6水平的改变及其相关性

目的 探讨脑梗死患者血浆硫化氢、同型半胱氨酸(Hcy)、叶酸和维生素B6水平的变化及其相关性.方法 检测60例脑梗死患者和40名正常对照者血浆硫化氢、Hcy、叶酸及维生素B6水平.脑梗死患者血浆硫化氢水平与Hcy、叶酸和维生素B6水平的相关性采用直线相关分析.结果 与正常对照组比较,脑梗死组血浆Hcy水平显著增高,血浆硫化氢、叶酸、维生素B6水平显著降低(P<0.05～0.001).血浆硫化氢水平与Hcy水平呈负相关(r=-0.6271,P<0.01),与叶酸及维生素B6水平呈正相关(r=0.5341,P<0.005;r=0.4615,P<0.05).结论 脑梗死患者血浆硫化氢、叶酸和维生素B6水平明显降低,Hcy水平升高.血浆低硫化氢水平可能参与了高Hcy血症致脑血管病的发病机制,可能是脑血管病的危险因素.     

血浆同型半胱氨酸与颅内动脉瘤的关系

目的 探讨血浆同型半胱氨酸(Hcy)、血清叶酸、维生素B12水平与颅内动脉瘤的关系.方法 采用化学发光法检测80例颅内动脉瘤患者和60例对照者血浆Hcy、血清叶酸、维生素B12水平,相关危险因索用logistic回归分析.结果 颅内动脉瘤组平均血浆Hcy水平明显高于对照组(P=0.005),两组中血浆Hcy升高分别有38例(48%)和9例(15%)(X2=16.239,P＜0.001);颅内动脉瘤组平均血清叶酸、维生素B12水平明显低于对照组(P=0.01;P=0.005);颅内动脉瘤患者血浆Hcy水平与血清叶酸、维生素B12水平呈负相关(P＜0.05).多因素logistic回归分析显示:血浆Hcy是颅内动脉瘤发病的独立危险因素,比值比(OR)=3.961[P=0.019,95%可信区间(CI):1.255～12.500].结论 高Hcy血症与颅内动脉瘤发病有密切关系,可能是颅内动脉瘤发病的一个独立危险因素;血浆Hcy水平升高可能与血清叶酸、维生素B12水平降低有关.     

帕金森病患者周围神经病变与血清叶酸维生素B_(12)水平的相关性

目的分析帕金森病患者周围神经病变与血清叶酸、维生素B12水平的相关性。方法随机选取100例帕金森病患者为病例组,同时选取与病例组性别、年龄、身体条件、生活区域相似的100例健康人为对照组,比较2组周围神经病变的发病情况以及血清叶酸、维生素B12水平。结果病例组周围神经病变发病率42.0%,对照组为16.0%,病例组明显高于对照组(P0.05)。病例组尺神经、正中神经传导速度虽较对照组有所降低,但差异无统计学意义(P0.05);病例组周围神经受损者的腓肠神经、胫神经传导速度明显较对照组低(P0.05),但病例组无周围神经受损者的腓肠神经、胫神经传导速度较对照组虽有所降低,但只与对照组无周围神经受损者差异有统计学意义(P0.05)。对照组维生素B12以及叶酸的浓度较病例组高,且其浓度与病例组患者的周围神经受损程度有明显的正相关性;病例组无周围神经受损者的维生素B12以及叶酸浓度较对照组中周围神经受损者低(P0.05)。结论帕金森病患者周围神经病变与血清叶酸、维生素B12水平呈负相关,患者血清叶酸、维生素B12水平越低,发生周围神经病变的可能性越大,病情越重。     

精神分裂症患者一级亲属的探索性眼球活动障碍研究

目的:探讨精神分裂症患者一级亲属探索性眼球活动(EEM)障碍的发生率及与血清一氧化氮/一氧化氮合成酶(NO/NOS)水平的关系。方法:共收集精神分裂症患者一级亲属193名(研究组),健康对照者150名(对照组)进行EEM检查,同时检测血清NO/NOS水平。结果:精神分裂症一级亲属的EEM异常率(52.3%)显著高于对照组(14.7%)(χ2=52,P<0.01);在精神分裂症一级亲属中,具有EEM障碍者的血清NO和NOS水平显著低于无EEM障碍者(t=2.83,P<0.01;t=2.53,P<0.05)。结论:精神分裂症患者一级亲属EEM障碍的发生率增高,并可能存在血清NO/NOS水平低下。     

血浆同型半胱氨酸与迟发性运动障碍患者认知功能的相关性研究

目的 探讨血浆同型半胱氨酸(homocysteine,Hcy)与迟发性运动障碍(tardive dyskinesia,TD)患者认知功能的关系.方法 对33例伴TD的精神分裂症患者进行血浆Hcy与血清维生素B12、叶酸水平检测以及韦氏记忆测定(WMS)、连线测验(TMT)和威斯康星卡片分类测验(WCST).结果 血浆Hcy水平与触觉、TMT(A、B)呈显著负相关,而与WCST未显示出明显的相关性;血清维生素B12水平与触觉、TMT-B及WCST中持续性应答数、概念化水平百分数呈显著正相关,血清叶酸水平与WMS、MT及WCST未显示出显著相关性.结论 TD患者认知损害可能与血浆Hcy水平及血清维生素B12水平有关.     

抗癫痫药物对卒中后癫痫患者血清同型半胱氨酸、叶酸、B族维生素水平的影响

目的探讨4种常用抗癫痫药物(AEDs)对卒中后癫痫(PSE)患者血清同型半胱氨酸(Hcy)、叶酸、维生素B_(12)、维生素B_6水平的影响。方法对规则口服AEDs 1年以上的194例PSE患者(AEDs治疗组)及新诊断未服药的40例PSE患者(对照组)进行血清Hcy、叶酸、维生素B_(12)、维生素B_6水平检测。探讨不同AEDs对患者上述指标的影响。结果与对照组相比,AEDs治疗组血清Hcy水平明显增高,血清叶酸、维生素B_(12)水平明显降低(均P0.05)。各组间血清维生素B_6水平的差异无统计学意义。与单药治疗亚组比较,联合用药亚组血清Hcy水平明显升高(P0.05)。与对照组相比,采用丙戊酸钠(VPA)、卡马西平(CBZ)、奥卡西平(OXC)单药治疗的患者血清Hcy水平显著增加,采用VPA、CBZ单药治疗的患者血清叶酸水平明显降低,采用VPA单药治疗的患者血清维生素B_(12)水平明显降低(均P0.05)。与对照组相比,采用VPA+CBZ、VPA+左乙拉西坦(LEV)、VPA+OXC、CBZ+LEV双药联合治疗及≥3种AEDs联合治疗的患者血清Hcy水平显著增加,采用VPA+LEV、VPA+OXC、CBZ+LEV双药联合治疗及≥3种AEDs联合治疗的患者血清叶酸水平明显降低,采用VPA+CBZ、VPA+OXC、CBZ+LEV双药联合治疗及≥3种AEDs联合治疗的患者血清维生素B_(12)水平明显降低(均P0.05)。AEDs治疗组高Hcy血症(HHcy)发生率(36.6%)明显高于对照组(20.0%)(χ~2=4.085,P=0.043)。其中联合用药亚组HHcy发生率(47.6%)与对照组比较差异有统计学意义(χ~2=6.950,P=0.008);单药治疗亚组HHcy发生率(33.6%)与对照组比较差异无统计学意义。VPA、CBZ单药治疗的患者HHcy发生率(40.5%;43.8%)明显高于对照组(χ~2=3.871,P=0.049;χ~2=4.726,P=0.030)。OXC、LEV单药治疗的患者HHcy发生率(29.2%;22.9%)与对照组比较差异无统计学意义。结论AEDs治疗对PSE患者血清维生素B_6水平的影响不大,但对其血清Hcy、叶酸、维生素B_(12)水平影响较大。联合应用AEDs或VPA、CBZ单药治疗可能增加PSE患者HHcy的发生率。     

Hyperhomocysteinemia and schizophrenia: case control study

Objectives

Homocysteine (Hcys) is a sulphur-containing amino acid that has been widely investigated for its putative role in neuropsychiatric disorders. Elevated plasma homocysteine levels have been associated with schizophrenia. Among other factors, low folate and vitamin B12 levels have been implicated in the increase in homocysteine. The aim of the study was to determine plasma Hcys, folate and vitamin B12, and the frequency and severity of hyperhomocysteinemia in patients with schizophrenia, and to investigate the association between Hcys and clinical features and its relationship with folate and vitamin B12 levels.

Methods

This was a case-control study carried out on 61 (54 males and seven females, mean age = 33.3 ± 9.2) inpatients with chronic schizophrenia according to DSM-IV criteria and 46 (25 males and 21 females, mean age = 45.9 ± 14.2) healthy controls. Most of patients (90.2%) were treated by first generation antipsychotics with a mean daily dosage of 401.6 mg chlorpromazine equivalents. Total homocysteine serum levels were determined quantitatively by fluorescence-polarization immunoassay (FPIA) with an AxSYM analyzer™ (Abbott). Quantitative vitamin B12 and folate serum levels were measured with an Elecsys 2010 analyzer™ (Roche Diagnostics). Differences between patients and controls were examined using a two-way Ancova with gender and diagnosis as independent variables, adjusting for age.

Results

Patients with schizophrenia showed higher plasma Hycs and lower plasma folate than controls (mean = 16.1 μmol/L in patients versus 10.9 μmol/L in controls; P = 0.028 for Hycs and 4.2 μg/L in patients versus 8.2 μg/L in controls; P < 0.001 for folate). Patients and controls did not differ in vitamin B12 levels. Both male and female patients had increased plasma Hcys compared to controls. Hyperhomocysteinemia (Hcys levels > 15 μmol/L) was present in 34.4% of the patients versus 15.2% in controls. The prevalence of moderate hyperhomocysteinemia (Hcys levels: 15–29 μmo/L) was 26.2% and that of intermediate hyperhomocysteinemia (Hcys levels: 30–100 μmol/L) was 8.2%. In patients with schizophrenia, plasma Hcys was not correlated with age (r = 0.07; P = 0.56), duration of illness (r = –0.04; P = 0.78) and did not differ with gender and clinical sub-types. Moreover, plasma Hcys was higher in patients without family history of psychiatric disorders (19.2 μmol/L) versus 12.7 μmol/L in patients with family history of psychiatric disorders (P = 0.032). Concerning therapeutic features, plasma Hcys did not differ with type of antipsychotic and was not related to daily dosage of antipsychotics. A negative correlation was found between plasma Hcys and vitamin B12 levels (r = –0.26; P = 0.04).

Conclusion

These results confirm an increase of Hcys levels in schizophrenic patients and suggest that it is associated with absence of family history of psychiatric disorders and with low vitamin B12 levels. Hyperhomocyteinemia could be related to the pathophysiology of aspects of this illness. Homocysteine should be considered as a factor to consider in monitoring and management of patients with schizophrenia.     

Correlations between cognitive, behavioural and psychological findings and levels of vitamin B12 and folate in patients with dementia

BACKGROUND: Associations between low levels of folate and vitamin B12 and cognitive impairment in patients with dementia have been reported. Some studies revealed correlations between low levels of vitamin B12 and behavioural and psychological signs and symptoms of dementia (BPSD) in Alzheimer's disease (AD) patients. Given the lack of studies in frontotemporal dementia (FTD) and on folate and given the methodological shortcomings of former publications, we set up a prospective study. METHODS: At inclusion, AD (n=152) and FTD (n=28) patients underwent a neuropsychological examination. Behaviour was assessed using a battery of behavioural assessment scales. Determination of serum vitamin B12 and red cell folate levels were performed within a time frame of two weeks of inclusion. RESULTS: In both patient groups, significantly negative correlations between levels of serum vitamin B12 and red cell folate and the degree of cognitive deterioration were found. No correlations with BPSD were found in the AD patient group. In FTD patients, levels of vitamin B12 were negatively correlated with both hallucinations (p=0.022) and diurnal rhythm disturbances (p=0.036). CONCLUSIONS: The observed negative correlations between levels of vitamin B12 and folate and cognitive impairment in both AD and FTD patients, raise the possibility of a non-specific etiological role. Although levels of vitamin B12 and folate did not correlate with BPSD in AD patients, negative correlations between serum vitamin B12 levels and BPSD in FTD patients were revealed. Decreased serum vitamin B12 levels may predispose FTD patients to develop hallucinations and diurnal rhythm disturbances.     

Serum homocysteine and folate levels in korean schizophrenic patients

Objective

This study was conducted to confirm the results of the authors'' previous research on schizophrenia manifesting high serum homocysteine and low folate levels. This study is anchored on a theory that a high serum homocysteine concentration affects schizophrenia by virtue of a neurotoxic mechanism, and on a report that some schizophrenia patients with high homocysteine levels benefited from high folate ingestion.

Methods

The serum homocysteine, folate, and vitamin B₁₂ levels of 236 normal-control-group subjects and 234 schizophrenia subjects who met the diagnostic criteria based on DSM-IV-TR were compared. The homocysteine levels were measured via fluorescence polarization immunoassay, and the folate and vitamin B₁₂ levels were determined via radioimmunoassay.

Results

The homocysteine levels of the patient group were significantly higher than those of the normal control group. The homocysteine level was more negatively correlated with the folate level in the schizophrenia group than in the control group. The percentages of female and male schizophrenia subjects manifesting high homocysteine levels were 33.8 and 51.5%, respectively. The percentage of schizophrenia subjects with low folate levels was 66.2%. In the low- and normal-folate-level groups, the patient group showed significantly higher homocysteine levels than the normal control group. The low-folate-level patient group particularly showed significantly higher homocysteine levels than the low-folate-level normal control group.

Conclusion

Some schizophrenia patients with high serum homocysteine levels may have the genetic defect of having low folate serum levels. In such cases, folate ingestion may be a good management modality for clinical improvement.     

复发—缓解型多发性硬化患者血清中CRP及Hcy水平分析

目的探讨复发—缓解型多发性硬化(RRMS)患者血清中C反应蛋白(CRP)、同型半胱氨酸(Hcy)、维生素B_(12)及叶酸水平,并探讨上述因子与RRMS发病的关系。方法选取21例急性期的RRMS患者作为RRMS组,21例同期住院的神经性头痛患者作为对照组,测定其血清中CRP、Hcy、叶酸及维生素B_(12)水平,并比较两组之间的水平差异;并比较RRMS组中不同性别、不同残疾程度组之间的血清CRP、Hcy、叶酸及维生素B_(12)水平。结果 RRMS组患者血清中CRP及Hcy水平高于对照组,而叶酸及维生素B_(12)水平低于对照组,(P0.05)。而扩展残疾状况评分量表评分(EDSS)4分的RRMS患者血清中Hcy及CRP水平高于EDSS评分≤4分的RRMS患者,(P0.05)。结论血清中高CRP、Hcy水平可能与RRMS发病及残疾程度有关。     

Serum folate, vitamin B12, and homocysteine in major depressive disorder, Part 2: predictors of relapse during the continuation phase of pharmacotherapy

OBJECTIVE: In the present study, we assessed the relationship between serum folate, vitamin B12, and homocysteine levels on the rate of relapse in outpatients with remitted major depressive disorder (MDD) during a 28-week continuation phase of treatment with fluoxetine. METHOD: Seventy-one outpatients (mean +/- SD age = 40.2 +/- 11.1 years; 56.3% women) with MDD (as assessed with the Structured Clinical Interview for DSM-III-R) who had remitted and who were enrolled in the continuation phase of treatment with fluoxetine had serum folate, vitamin B12, and homocysteine measurements completed at baseline (prior to acute-phase treatment). Patients were followed for 28 weeks of continued treatment with fluoxetine 40 mg/day to monitor for depressive relapse. Folate levels were classified as either low (< or = 2.5 ng/mL) or normal. Vitamin B12 levels were classified as either low (< or = 200 pg/mL) or normal. Homocysteine levels were classified as either elevated (> or = 13.2 micromol/L) or normal. With the use of separate logistic regressions, we then assessed the relationship between folate, vitamin B12, and homocysteine level status and relapse. The study was conducted from November 1992 to January 1999. RESULTS: The presence of low serum folate levels (p =.004), but not low B12 (p >.05) or elevated homocysteine levels (p >.05), was associated with relapse during continuation treatment with fluoxetine. The relapse rates for patients with (N = 7) and without (N = 64) low folate levels were 42.9% versus 3.2%, respectively. CONCLUSION: Low serum folate levels were found to place patients with remitted MDD at risk for depressive relapse during the continuation phase of treatment with fluoxetine.     

Serum folate, vitamin B12, and homocysteine in major depressive disorder, Part 1: predictors of clinical response in fluoxetine-resistant depression

OBJECTIVE: In the present study, we assessed the relationship between serum folate, vitamin B12, and homocysteine levels and clinical response in patients with major depressive disorder (MDD) who had previously failed to respond to open treatment with fluoxetine 20 mg/day and were enrolled in a 4-week, double-blind trial of either (1) fluoxetine dose increase, (2) lithium augmentation of fluoxetine, or (3) desipramine augmentation of fluoxetine. METHOD: Fifty-five outpatients (mean +/- SD age = 41.7 +/- 10.6 years; 50.9% women) with MDD as assessed with the Structured Clinical Interview for DSM-III-R who were enrolled in the double-blind trial had serum folate, vitamin B12, and homocysteine measurements completed at baseline (prior to fluoxetine treatment initiation). Folate levels were classified as either low (< or = 2.5 ng/mL) or normal. Vitamin B12 levels were classified as either low (< or = 200 pg/mL) or normal. Homocysteine levels were classified as either elevated (> or = 13.2 micromol/L) or normal. With the use of a logistic regression, we then assessed the relationship between (1) low or normal folate levels, (2) normal or low B12 levels, and (3) elevated or normal homocysteine levels and clinical response to double-blind treatment. The study was conducted from November 1992 to January 1999. RESULTS: Low serum folate levels (chi2=3.626, p =.04), but not elevated homocysteine (p >.05) or low vitamin B12 levels (p >.05), were associated with poorer response to treatment. The response rates for patients with (N = 14) and without (N = 38) low folate levels were 7.1% versus 44.7%, respectively. CONCLUSION: Low serum folate levels were found to be associated with further treatment resistance among patients with fluoxetine-resistant MDD.     

Serum Pyridoxal, Folate, and Vitamin B12 Levels in Institutionalized Epileptics

Serum pyridoxal, folate, and vitamin B12 concentrations were measured in 68 institutionalized patients with severe epilepsy. Twenty-five patients had a reduced level of pyridoxal and thirty-three a reduced level of folate. There was no instance of a low serum vitamin B12 although in three patients the levels were found to be abnormally high. Fifteen patients had both a low serum pyridoxal and a low serum folate but there was no significant correlation. All patients had a normal hemoglobin concentration and a normal mean corpuscular volume. There was no close relationship between reduced serum vitamin levels and single or groups of anticonvulsant agents, although the size of the groups was too small to permit a detailed study.     

Vitamin B(12) and folate in relation to the development of Alzheimer's disease

OBJECTIVE: To explore the associations of low serum levels of vitamin B(12) and folate with AD occurrence. METHODS: A population-based longitudinal study in Sweden, the Kungsholmen PROJECT: A random sample of 370 nondemented persons, aged 75 years and older and not treated with B(12) and folate, was followed for 3 years to detect incident AD cases. Two cut-off points were used to define low levels of vitamin B(12) (< or =150 and < or =250 pmol/L) and folate (< or =10 and < or =12 nmol/L), and all analyses were performed using both definitions. AD and other types of dementia were diagnosed by specialists according to DSM-III-R criteria. RESULTS: When using B(12) < or =150 pmol/L and folate < or =10 nmol/L to define low levels, compared with people with normal levels of both vitamins, subjects with low levels of B(12) or folate had twice higher risks of developing AD (relative risk [RR] = 2.1, 95% CI = 1.2 to 3.5). These associations were even stronger in subjects with good baseline cognition (RR = 3.1, 95% CI = 1.1 to 8.4). Similar relative risks of AD were found in subjects with low levels of B(12) or folate and among those with both vitamins at low levels. A comparable pattern was detected when low vitamin levels were defined as B(12) < or =250 pmol/L and folate < or =12 nmol/L. CONCLUSIONS: This study suggests that vitamin B(12) and folate may be involved in the development of AD. A clear association was detected only when both vitamins were taken into account, especially among the cognitively intact subjects. No interaction was found between the two vitamins. Monitoring serum B(12) and folate concentration in the elderly may be relevant for prevention of AD.     

血清叶酸、维生素B12水平与脑梗死的关系

目的为探讨血清叶酸、维生素B12水平与脑梗死的关系.方法运用放射免疫分析法检测50例脑梗死患者和44例正常对照组的血清叶酸、维生素B12浓度.结果脑梗死组血清叶酸、维生素B12浓度分别为(5.97±1.96)μg/ml、(511.47±212.06)μg/ml;对照组分别为(8.08±2.25)μg/ml、(806.91±254.60)μg/ml.脑梗死组血清叶酸、维生素B12水平均明显低于对照组,两组有显著性差异(P＜0.01).结论提示血清叶酸、维生素B12水平下降与脑梗死的发生有关,可能是其中又一危险因素.     

Serum vitamin B12, folate,and homocysteine levels and their association with clinical and electrophysiological parameters in multiple sclerosis

Patients with multiple sclerosis (MS) may have low serum vitamin B12 and folate levels and high levels of homocysteine. We aimed to evaluate serum vitamin B12, folate, homocysteine, mean corpuscular volume (MCV), hemoglobin (Hb), and hematocrit (Hct) levels in patients with MS. We examined the relationship between these parameters and age, sex, disease type, age at onset, disease duration, Expanded Disability Status Score, immunoglobulin G (IgG) index, oligoclonal band presence, visual evoked potentials (VEP) and posterior tibial somatosensory evoked potentials (SEP). These parameters were evaluated in 35 patients during an acute attack and compared to data collected from 30 healthy individuals (control subjects). Serum vitamin B12, folate, homocysteine, Hb, and Hct levels and MCV were low in a proportion of patients with MS (20%, 14.3%, 20%, 6.7%, 3.3% and 10% respectively), whereas only vitamin B12 and folate levels were low in only 3.3% of the control subjects. Homocysteine levels were high in 20% of patients with MS but were within normal limits in the control group. Elevated Hct levels were significantly correlated (p < 0.05) with prolonged posterior tibial SEP P1 and P2 latencies compared to the control subjects. Patients with MS who had prolonged VEP and posterior tibial SEP P1 and P2 latencies also had lower vitamin B12 levels compared to patients with normal latencies. Thus, we found a significant relationship between MS and vitamin B12 deficiency, and also demonstrated a relationship between vitamin B12 deficiency, VEP and posterior tibial SEP in MS.