MTHFR基因多态性与河南中部地区汉族人群急性冠脉综合征发生的关联性研究

目的探讨5,10-亚甲基四氢叶酸还原酶(MTHFR)基因多态性与河南中部地区汉族人群急性冠脉综合征(ACS)发生的关联性。方法招募河南中部地区汉族ACS患者280例作为观察组,选取同期行健康体检的河南中部地区汉族健康受试者286名作为对照组。采用荧光染色原位杂交技术检测两组MTHFR基因C677T、A1298C位点基因型,比较两组受试者各基因型及等位基因分布的差异,采用二元Logistic回归分析MTHFR基因多态性与ACS发生的关联性。结果两组各基因型分布频率均符合Hardy-Weinberg平衡(P0.05)。对照组MTHFR C677T位点CC、CT、TT型分布频率分别为31.82%、47.90%、20.28%,MTHFR A1298C位点AA、AC、CC型分布频率分别为73.78%、21.68%、4.54%;观察组MTHFR C677T位点CC、CT、TT型分布频率分别为16.43%、40.71%、42.86%,MTHFR A1298C位点AA、AC、CC型分布频率分别为69.29%、27.14%、3.57%。两组受试者MTHFR C677T各基因型分布频率及等位基因频率比较差异有统计学意义(P0.05),而MTHFR A1298C各基因型分布频率及等位基因频率比较差异无统计学意义(P0.05)。二元Logistic回归分析显示,MTHFR C677T基因型是ACS发生的影响因素(P0.05),以TT型为参照,CC型发生ACS的可能性是TT型的24.4%,CT型发生ACS的可能性是TT型的40.2%。结论 MTHFR基因多态性与河南中部地区汉族人群ACS发生有关,其中C677T位点突变可能是ACS发生的影响因素,而A1298C位点基因多态性与ACS发生的关联性较低。     

亚甲基四氢叶酸还原酶基因多态性对小剂量甲氨喋呤治疗类风湿关节炎不良反应的影响

目的探讨亚甲基四氢叶酸还原酶（MTHFR）基因C677T多态性对小剂量甲氨喋呤（MTX）治疗类风湿关节炎的影响。方法收集类风湿关节炎患者治疗前及治疗后0,12,24及48 w的临床表现及实验室指标和不良反应信息,评估疗效。采用实时荧光定量聚合酶链反应（FQ-PCR）方法测定类风湿关节炎患者183例（RA组）及健康对照组100例的MTHFR基因C677T多态性,比较两组间基因型分布及等位基因频率。结果 C677T基因型分布在RA组与健康对照组间差异无统计学意义（P〉0.05）;C677T各基因型在MTX治疗有效率差异无统计学意义（P〉0.05）。TT基因型组肝毒性及血液系统不良反应的发生率明显高于CC基因型组,差异均有统计学意义（P〈0.05）。结论 MTHFR基因C677T多态性与RA发病和MTX疗效无关,但与MTX治疗后血液系统不良反应、肝毒性有关联。     

MTHFR基因多态性与肺血栓栓塞症的关系

目的探讨亚甲基四氢叶酸还原酶(MTHFR)基因多态性与肺栓塞的关系。方法选取肺栓塞患者102例及同期住院或门诊患者及健康体检者120例,应用聚合酶链反应-限制性片段长度多态性(PCR-RFLP)方法进行检测两组MTHFR基因C677T、A1298C位点的多态性,比较两组基因型和等位基因分布频率。结果 1在肺栓塞组中,MTHFR C677T位点CC、C/T、TT基因型频率分别为20.6%、31.4%、48%,在对照组中分别为29.2%、39.1%、31.7%,在两组中TT基因型频率差异有统计学意义(P=0.013)。在两组间,T等位基因分布频率差异有统计学意义(P=0.008)。2在肺栓塞组中,MTHFR A1298C位点AA、A/C、CC基因型频率分别为23.5%、31.4%、45.1%,在对照组中分别为31.7%、37.5%、30.8%,在两组中CC基因型频率差异有统计学意义(P=0.029),等位基因C分布频率两组间差异有统计学意义(P=0.018)。结论MTHFR基因C677T位点的TT基因型及A1298C位点的CC基因型多态性可能为肺血栓栓塞症的高危因素。     

亚甲基四氢叶酸还原酶基因多态性与不良妊娠结局的关系分析

目的探讨亚甲基四氢叶酸还原酶(MTHFR)基因多态性与不良妊娠结局的关系。方法选取2018年6月至2019年6月我院收治的既往存在不良妊娠结局的育龄期女性120例为观察组,选择同期在我院就诊的无不良妊娠病史的育龄期妇女120例为对照组,检测比较两组妇女的MTHFR C677T、A1298C位点基因型、等位基因频率分布情况。结果两组妇女C677T位点的基因型(CC、CT、TT)、A1298C位点的基因型(AA、AC、CC)频率分布比较差异均有统计学意义(P0.05)。两组妇女C677T位点的等位基因(C、T)、A1298C位点的等位基因(A、C)频率分布比较差异均有统计学意义(P0.05)。结论 MTHFR基因多态性可能与育龄期女性不良妊娠结局的发生有关。     

同型半胱氨酸水平与N5,10-亚甲基四氢叶酸还原酶基因多态性的关系

目的:探索高血压人群中同型半胱氨酸(Hcy)水平与N5,10-亚甲基四氢叶酸还原酶(MTHFR)C677T基因多态性和其他相关因素的关系。方法:应用配对方法选取241例原发性高血压患者,应用高效液相色谱荧光检测法测定血浆Hcy水平,用聚合酶链反应-限制性片段的多态性技术检测MTHFR基因C677T多态性。结果:①相关分析显示,TT基因型患者Hcy平均水平大于CC基因型和CT基因型患者,调整混杂因素前后差异有统计学意义(P<0.01);CC基因型和CT基因型之间差异无统计学意义(男性P=0.899,女性P=0.921)。②男性Hcy[(12.8±7.2)μmol/L]高于女性[(9.7±4.7)μmol/L],男性H-型高血压的比例(60.3%)高于女性(29.6%)。③logistic回归模型显示,TT基因型患者中H型高血压的比例(80.6%)高于CT和CC基因型,男性在调整混杂因素前后差异有统计学意义(P<0.05);女性在合并CC、CT基因型后与TT基因型的比较中,差异有统计学意义(P<0.05)。结论:高血压人群中MTHFR基因C677T纯合突变可能是Hcy升高和H型高血压的重要遗传因素,而且存在性别差...     

MTHFR基因多态性与肺癌易感性的关系

目的探讨黑龙江地区汉族人群亚甲基四氢叶酸还原酶(MTHFR)C677T、A1298C基因多态性分布与肺癌易感性的关系。方法纳入225例肺癌患者作为实验组,以门诊体检健康人群为对照组,采用Sanger双脱氧链终止法检测目标人群MTHFR基因C677T、A1298C的基因型。结果实验组MTHFR基因C677T突变纯合型(TT)分布频率显著高于对照组(23.1%vs 10.7%,P0.05),携带TT基因型患肺癌的风险比值比为2.517,95%CI为1.490-4.254;MTHFR A1298C各基因型分布频率实验组与对照组之间比较差异无统计学意义(P0.05)。结论 MTHFR基因C677T突变纯合型(TT)与肺癌易感性明显相关,未发现A1298C与肺癌发生相关。     

亚甲基四氢叶酸还原酶基因多态性与女性不良妊娠结局的关系研究

目的探讨亚甲基四氢叶酸还原酶(MTHFR)的基因多态性与女性不良妊娠结局的关系。方法选取2017年8月至2019年8月我院收治的曾经发生不良妊娠结局的育龄期妇女130例作为观察组,选择同期来我院就诊的无不良妊娠病史的已育妇女110例作为对照组,检测比较两组研究对象MTHFR A1298C、C677T位点的基因型、等位基因频率分布情况。结果两组研究对象的MTHFR A1298C位点的基因型(AA、AC、CC)以及等位基因(A、C)的频率分布情况比较,差异有统计学意义(P0.05)。两组研究对象的MTHFR C677T位点的基因型(CC、CT、TT)以及等位基因(C、T)的频率分布情况比较,差异有统计学意义(P0.05)。结论 MTHFR的基因多态性可能与女性不良妊娠结局的发生有关。     

氨基咪唑氨甲酰转移酶基因多态性在类风湿关节炎患者甲氨蝶呤治疗中的研究

目的 探讨类风湿关节炎(RA)患者氨基咪唑氨甲酰转移酶(ATIC)基因347C/G(rs2372536)单核苷酸多态性(SNP)与甲氨蝶呤(MTX)疗效和不良反应的相关性.方法 收集RA患者359例,分为单用MTX组、MTX联用其他改善病情药(DMARDs)组、非MTX的DMARDs组,于治疗前和治疗后12、24周检查患者临床及实验室指标,评价疗效(采用ACR20)及不良反应.采用实时荧光定量聚合酶链反应(PCR)法检测RA患者及340名健康对照组的ATIC基因C347G多态性,比较2组间基因型分布及等位基因频率.结果 RA与健康对照组ATIC基因347C/G基因型分布频率差异无统计学意义(P>0.05).单用MTX治疗组的有效率为72%(77/107例),有效组ATIC 347CC,CG,GG基因型与无效组间差异无统计学意义(P>0.05),不良反应发生率为32.7%,且携带ATIC G等位基因型患者的不良反应发生率(22.4%)明显高于CC基因型组(10.3%)(OR=2.67,95%可信区间为1.27～5.59),差异有统计学意义(P<0.05).MTX联用其他DMARDs(128例)组及非MTX的DMARDs组(90例),ATIC基因多态性与其疗效及不良反应无关(P>0.05).结论 ATIC基因347C/G多态性在RA患者与健康对照组间差异无统计学意义;与MTX治疗RA的疗效无明显相关性,但ATIC G等位基因与MTX的不良反应密切相关.因此ATIC基因347C/G多态性可能作为患者使用MTX的出现不良反应的预测指标.     

MTHFR C677T基因多态性与冠心病患者同型半胱氨酸及冠脉狭窄程度的相关性

[摘 要] 目的 探讨MTHFR C677T基因多态性与河南中部汉族冠心病（CHD）患者同型半胱氨酸(Hcy)及冠脉狭窄程度的相关性。方法 应用荧光染色原位杂交技术对河南中部汉族352例CHD患者和340例非CHD对照者进行MTHFR C677T基因多态性检测,并比较两组不同基因型之间Hcy水平的差异。采用Gensini评分系统评价CHD患者的冠脉狭窄程度,多元线性回归分析法探讨MTHFR C677T基因多态性以及其他因素与Gensini得分之间的相关性。结果 非CHD组MTHFR C677T 基因CC、CT、TT 型例数及分布频率分别为113(33.2％)、159(46.8％)、68(20％),CHD组MTHFR C677T位点CC、CT、TT型例数及分布频率分别为85(24.1％)、157(44.6％)、110(31.3％)。两组受试者各基因型分布频率均符合Hardy-Weinberg 平衡（P＞0.05）。两组受试者MTHFR C677T各基因型分布频率及等位基因频率比较,差异均有统计学意义（P＜0.001）。CHD组血清Hcy水平、高血压、糖尿病患病率分别为（23.1±8.7）、27.8%和16.8%,均高于非CHD组的（18.6±7.4）、10.6%和6.2%,差异均有统计学意义（P <0.05）。两组不同基因型之间血清Hcy水平差异有统计学意义（P <0.05）。多元线性回归分析结果显示,MTHFR C677T基因多态性与Gensini得分的相关性无统计学意义（β=-0.16,95%CI：-0.21～0.18,P=0.785）。结论MTHFR C677T基因多态性影响Hcy水平,但与CHD患者冠脉狭窄程度无明显相关性。     

亚甲基四氢叶酸还原酶基因C677T、A1298C和G1793A多态性与血液透析患者血浆Hcy水平的关系

目的探讨亚甲基四氢叶酸还原酶(MTHFR)基因C677T、A1298C和G1793A多态性与血液透析患者血浆同型半胱氨酸(Hcy)水平的关系。方法接受血液透析的慢性肾衰竭患者(疾病组)88例的外周血标本,采用直接测序法对MTHFR基因3个标签(C677T、A1298C和G1793A)单核苷酸多态性(SNPs)进行基因分型,选取同期92例健康体检者的外周血作对比(对照组),比较两组以上SNPs位点基因型和等位基因的分布差异,采用酶联免疫吸附法检测血浆Hcy水平并比较疾病组MTHFR基因SNPs位点各基因型的血浆Hcy水平,以比值比(OR)及其95%置信区间(CI)评价以上SNPs发生Hcy升高的风险情况。结果两组C677T和G1793A基因型和等位基因分布差异有统计学意义(P0.05),其中疾病组C677T TT基因型和T等位基因的比例及G1793A AA基因型和A等位基因的比例明显高于对照组(P0.05)。疾病组血浆Hcy水平为(38.25±4.67)μmol/L,显著高于对照组的(19.36±2.59)μmol/L(P0.05)。疾病组C677T TT型的血浆Hcy水平高于CC、CT型,CT型高于CC型,G1793A AA型的血浆Hcy水平高于GG、GA型,GA型高于GG型,差异均有统计学意义(均P0.05)。C677T TT基因型较CC型血浆Hcy水平升高的风险升高至3.429倍(P0.05),而GA、GA+AA型血浆Hcy水平升高的风险未改变(P0.05);以C等位基因为参照,携带T等位基因者Hcy水平升高的风险升高至2.050倍(P0.05)。A1298C、G1793A位点血浆Hcy水平升高的风险均未改变(P0.05)。结论MTHFR C677T和G1793A携带突变基因者的血浆Hcy水平升高,其中C677TT等位基因的血浆Hcy水平升高的风险升高,在预测血液透析患者血浆Hcy水平异常上有一定价值。     

Methylenetetrahydrofolate reductase polymorphisms, C677T and A1298C, are associated with methotrexate-related toxicities in Korean patients with rheumatoid arthritis

We investigated associations between the methylenetetrahydrofolate reductase (MTHFR) polymorphisms C677T and A1298C and methotrexate (MTX)-related toxicities in Korean patients with rheumatoid arthritis (RA) taking MTX. One hundred sixty-seven patients with RA were enrolled in a cross-sectional study and genotyped for the single-nucleotide polymorphisms C677T and A1298C in MTHFR. Alleles, genotypes, and haplotypes of the C677T and A1298C polymorphisms were not associated with specific MTX toxicities. However, among RA patients with the 1298CC genotype, the proportion who experienced at least one toxicity was significantly greater than the proportion of patients with 1298AA who did (P?=?0.043). In addition, the proportion of patients with the 677C/1298A haplotype who experienced toxicity was greater than the proportion of those with 677C/1298C who did (P?=?0.032, odds ratio?=?2.085, 95% confidence interval 1.058–4.106). In this study, MTHFR polymorphisms were associated with MTX toxicities in Korean patients with RA. Further study for association of MTHFR polymorphisms with MTX toxicities should be needed in larger RA population.     

Association of the MTHFR C677T and A1298C polymorphisms with methotrexate toxicity in rheumatoid arthritis: a meta-analysis

The aim of this study was to explore whether the C677T and A1298C polymorphisms of methylenetetrahydrofolate reductase (MTHFR) play a role in methotrexate (MTX) toxicity in rheumatoid arthritis (RA). MEDLINE and EMBASE database searches and subsequent manual searches were utilized to identify articles in which C677T and A1298C MTHFR polymorphisms were evaluated in RA patients taking MTX. A meta-analysis was conducted to identify associations between MTHFR polymorphisms and MTX toxicity. Twelve studies comprising a total of 2,288 RA patients were included in our meta-analysis. Meta-analysis revealed an association between the overall toxicity of MTX and the MTHFR 677TT genotype (odds ratio [OR]?=?1.615, 95 % confidence interval [CI]?=?1.185–2.200, p?=?0.002). Stratification by ethnicity indicated an association between the MTHFR 677TT genotype and the overall toxicity of MTX in East Asians (OR?=?1.583, 95 % CI?=?1.075–2.331, p?=?0.020). The toxicity of MTX also was found to be associated with the TT genotype in patients taking folate (OR?=?1.893, 95 % CI?=?1.283–2.793, p?=?0.001). Stratification by toxicity type indicated an association between the MTHFR 677TT genotype and any adverse effects (OR?=?1.716, 95 % CI?=?1.127–2.612, p?=?0.012). Meta-analysis stratified by toxicity type indicated an association between the MTHFR 1298CC genotype and any adverse effects (OR?=?0.501, 95 % CI?=?0.284–0.886, p?=?0.017). The results of our meta-analysis suggest that the MTHFR C677T and A1298C polymorphisms are associated with MTX toxicity in RA patients.     

The C677T mutation in the methylenetetrahydrofolate reductase gene: a genetic risk factor for methotrexate-related elevation of liver enzymes in rheumatoid arthritis patients.

OBJECTIVE: To study the possible relationship between the C677T mutation in the methylenetetrahydrofolate reductase (MTHFR) gene and the toxicity and efficacy of treatment with methotrexate (MTX) in patients with rheumatoid arthritis (RA). METHODS: Genotype analysis of the MTHFR gene was done in 236 patients who started MTX treatment with (n = 157) or without (n = 79) folic or folinic acid supplementation. Outcomes were parameters of efficacy of MTX treatment, patient withdrawal due to adverse events, discontinuation of MTX treatment because of elevated liver enzyme levels, and the total occurrence of elevated liver enzyme levels during the study. Multivariate logistic regression analysis was used to study the relationship between the presence of the MTHFR C677T mutation and toxicity outcomes of MTX treatment. RESULTS: Forty-eight percent of the patients showed the homozygous (T/T) or heterozygous (T/C) mutation. The presence of the C677CT or C677TT genotypes was associated with an increased risk of discontinuing MTX treatment because of adverse events (relative risk 2.01; 95% confidence interval 1.09, 3.70), mainly due to an increased risk of elevated liver enzyme levels (relative risk 2.38; 95% confidence interval 1.06, 5.34). Efficacy parameters were not significantly different between the patients with and those without the mutation. CONCLUSION: The C677T mutation is the first identified genetic risk factor for elevated alanine aminotransferase values during MTX treatment in patients with RA. We postulate that the incidence of clinically important elevation of liver enzyme levels during MTX treatment is mediated by homocysteine metabolism. Supplementation with folic or folinic acid reduced the risk of toxicity-related discontinuation of MTX treatment both in patients with and in patients without the mutation.     

Polymorphisms of the methylenetetrahydrofolate reductase gene and clinical outcomes in HLA-matched sibling allogeneic hematopoietic stem cell transplantation

To evaluate whether the C677T and A1298C polymorphisms of 5,10-methylenetetrahydrofolate reductase (MTHFR) are related to the toxicity of methotrexate (MTX) used in allogeneic stem cell transplantation, we performed association analysis between these genetic polymorphisms and the clinical outcomes of patients treated using human leukocyte antigen-matched sibling stem cell transplantation. Patients (n=72) with hematological malignancy or aplastic anemia were given a short course of MTX as a graft-versus-host disease prophylaxis. Patients with the 677TT genotype showed higher total bilirubin levels (677TT vs 677CT vs 677CC, 14.5 vs 8.6 vs 3.8 mg/dl, respectively; p=0.07) and higher aspartic transaminase levels (677TT vs 677CT vs 677CC, 678.9 vs 156.6 vs 111.8 IU/l; p=0.04). Platelet recovery to 20,000/μl was slower for patients with the 677TT genotype than for patients with other genotypes (677TT, 59 days; 677CT, 26 days; 677CC, 26 days; p=0.0075). The influences of the C677T polymorphism on treatment-related mortality (TRM) were also analyzed. One-year cumulative TRMs for patients with the TT genotype and the other genotypes were 66 and 30% (p=0.04) and their respective 1-year overall survivals were 30 and 56% (p=0.11). No association was observed between the A1298C polymorphism and clinical outcome for any of the different genotypes. Therefore, patients at high risk of developing hepatic toxicity and with a poor likelihood of survival could be selected by genotyping MTHFR C677T before allogeneic stem cell transplantation.     

Mutations C677T and A1298C of the 5,10-methylenetetrahydrofolate reductase gene and fasting plasma homocysteine levels are not associated with the increased risk of venous thromboembolic disease.

Mild hyperhomocysteinemia is associated with homozygosity for the thermolabile variant of 5,10-methylenetetrahydrofolate reductase (MTHFR) and could increase the risk of venous thromboembolic disease (VTD). Recently, the second A1298C mutation of the MTHFR gene was described. The present study aimed to analyze both mutations of the MTHFR gene and plasma homocysteine levels in subjects with VTD. The study groups comprised 146 patients with VTD and 100 healthy subjects. There were no statistical differences in carrier frequency and allelic frequency for both A1298C and C677T mutations, nor were there any differences encountered between subjects with VTD and controls in either plasma homocysteine levels or according to C677T or A1298C genotypes of MTHFR. In our VTD patients and controls, neither MTHFR 677CT/1298CC nor MTHFR 677TT/1298CC combined genotypes were observed; double heterozygotes (A1298C/C677T) were represented only in 11% of VTD patients, and in 15% of the controls. In conclusion, the polymorphisms C677T and A1298C of MTHFR and fasting plasma homocysteine levels do not seem to be significant risk factors for venous thromboembolic disease.     

Methotrexate related adverse effects in patients with rheumatoid arthritis are associated with the A1298C polymorphism of the MTHFR gene

BACKGROUND: There is an association between C677T polymorphism of the methylenetetrahydrofolate reductase (MTHFR) gene and methotrexate related toxicity. OBJECTIVE: To examine the relations between the recently described A1298C polymorphism of the MTHFR gene, plasma homocysteine, methotrexate toxicity, and disease activity in patients with rheumatoid arthritis. DESIGN: A cross sectional study on 93 methotrexate treated patients with rheumatoid arthritis, comprising a clinical interview and physical examination to determine disease activity and methotrexate related adverse reactions. Genotype analysis of the MTHFR gene was carried out and fasting plasma homocysteine and serum folate concentrations were measured. The data were analysed using univariate analysis. Allele and genotype distributions were compared with those of a healthy control group. RESULTS: The frequency of the 1298CC genotype (24.7%) in the rheumatoid study group was greater than expected in the general population (12.8%, p<0.001). This genotype was associated with a significantly low rate of methotrexate related side effects. The odds ratio for side effects in patients with wild type 1298AA genotype v 1298CC genotype was 5.24 (95% confidence interval, 1.38 to 20). No correlation of disease activity variables or plasma homocysteine with MTHFR A1298C and C677T polymorphisms was observed. CONCLUSIONS: 1298CC polymorphism was more common in methotrexate treated rheumatoid patients than expected in the population, and was associated with a reduction in methotrexate related adverse effects. The A1298C polymorphism of the MTHFR gene may indicate a need to adjust the dose of methotrexate given to patients with rheumatoid arthritis.     

Efficacy and toxicity of methotrexate in early rheumatoid arthritis are associated with single-nucleotide polymorphisms in genes coding for folate pathway enzymes

OBJECTIVE: To determine associations of methotrexate (MTX) efficacy and toxicity with single-nucleotide polymorphisms (SNPs) in genes coding for folate pathway enzymes in patients with early rheumatoid arthritis (RA). METHODS: Patients (n=205) with active RA received MTX at an initial dosage of 7.5 mg/week, which was increased to 15 mg/week and combined with folic acid (1 mg/day) after 4 weeks. If the Disease Activity Score in 44 joints (DAS44) was >2.4 at 3 months, MTX was increased to 25 mg/week. MTX efficacy was evaluated at 3 and 6 months and compared for genotypes in 3 analyses: patients with and without good response (DAS441.2), and patients with and without moderate improvement (DeltaDAS44>0.6). The association between MTX-related adverse drug events (ADEs) and genotype was evaluated by comparing genotypes between patients with and without ADEs, specifically pneumonitis, gastrointestinal ADEs, skin and mucosal ADEs, and elevated liver enzyme levels. The following SNPs were analyzed: methylenetetrahydrofolate reductase (MTHFR) 677C>T, MTHFR 1298A>C, dihydrofolate reductase (DHFR) -473G>A, DHFR 35289G>A, and reduced folate carrier 80G>A. In case of significant differences, odds ratios (ORs) were calculated. RESULTS: At 6 months, MTHFR 1298AA was associated with good improvement relative to 1298C (OR 2.3, 95% confidence interval [95% CI] 1.18-4.41), which increased with increased copies of the MTHFR 677CC haplotype. In contrast, MTHFR 1298C allele carriers developed more ADEs (OR 2.5, 95% CI 1.32-4.72). CONCLUSION: Patients with MTHFR 1298AA and MTHFR 677CC showed greater clinical improvement with MTX, whereas only the MTHFR 1298C allele was associated with toxicity. In the future, MTHFR genotypes may help determine which patients will benefit most from MTX treatment.     

Cost-effectiveness analysis of MTHFR polymorphism screening by polymerase chain reaction in Korean patients with rheumatoid arthritis receiving methotrexate

OBJECTIVE: To determine whether a strategy based on methylenetetrahydrofolate reductase (MTHFR) genotype screening is more cost-effective than the conventional strategy in reducing the risk of methotrexate (MTX)-related toxicity in patients with rheumatoid arthritis (RA). METHODS: We consecutively enrolled 385 patients with RA (355 female, 30 male) who had received MTX and identified toxicity associated with MTHFR C677T genotypes. We designed a hypothetical decision model to compare the genotype-based strategy with the conventional strategy. The time horizon was set as 1 year, and direct medical costs were used. The measured outcomes were the total expected cost, the effectiveness, and the incremental cost-effectiveness ratio. RESULTS: MTHFR genotype distribution revealed 133 patients (34.6%) with 677CC, 193 (50.1%) with 677CT, and 59 (15.3%) with 677TT. A total of 154 patients (40.0%) exhibited MTX-related toxicity. Compared to RA patients with the CC genotype, the odds ratio (95% confidence interval) for risk of toxicity was 3.8 (2.29-6.33) for the CT genotype, and 4.7 (2.40-9.04) for the TT genotype. In the base-case model, the total expected cost and the probability of continuing MTX medication for the conventional and genotype-based strategies were 851,415 Korean won (710 US dollars) and 788,664 Korean won (658 US dollars), and 94.03% and 95.58%, respectively. CONCLUSION: The MTHFR C677T polymorphism may be an important predictor of MTX-related toxicity in patients with RA. The cost-effectiveness analysis suggests that the genotype-based strategy is both less costly and more effective than the conventional strategy for MTX therapy.