Serum Homocysteine Levels In Patients Research Articles

Genome-wide analysis of DNA methylation and its relationship with serum homocysteine levels in patients with hypertension.

Homocysteine (Hcy) is an independent risk factor for cardiovascular diseases, and elevated plasma Hcy levels could aggravate vascular injury in hypertension. Hyperhomocysteinemia can change the methylation status of global DNA and specific genes. In the present study, we aim to examine the comprehensive influence of Hcy levels on DNA methylation status in patients with hypertension. Epigenome-wide methylation profiles of the peripheral leukocyte DNA of 218 patients with hypertension were analyzed using the Illumina Infinium Methylation EPIC BeadChip. Differentially methylated positions (DMPs) associated with serum Hcy levels were identified by mixed linear regression with the adjustment of potential confounders. Gene Ontology analysis and Kyoto Encyclopedia of Genes and Genomes pathway analysis were conducted to determine the potential functions of the identified DMPs. The association between the methylation level of DMPs and carotid-femoral pulse wave velocity (Cf-PWV) was also analyzed. Five DMPs at cg13169662, cg03179312, cg21976560, cg25262698, and cg09433843 showed significant association with serum Hcy levels (false discovery rate-corrected P < 0.05). An additional six CpG sites met the threshold for suggestive significance ( P < 1 × 10 -6 ), among which three DMPs (cg25781123, cg26463106, and cg06679221) were annotated to THUMPD3 . Furthermore, the methylation levels of cg13169662 and cg25262698 (RPRD1A) were significantly associated with Cf-PWV. Our results suggest that Hcy could induce DNA methylation alteration in patients with hypertension. Further functional research is warranted to elucidate the concrete role of DMPs in hypertension.

STUDY OF PREVALENCE OF HYPERHOMOCYSTEINEMIA IN CHRONIC KIDNEY DISEASEPATIENTS AT TERTIARY CARE HOSPITAL IN NORTHWEST MAHARASHTRA

Introduction-Chronic Kidney Disease is growing problem across all over world and India as well. Chronic kidney disease encompasses a spectrum of different pathophysiological processes associated with abnormal kidney function and a progressive decline in glomerular filtration rate(GFR).The risk for cardiovascular disease (CVD) morbidity and mortality remains high in all stages of CKD, including in patients with hemodialysis. More patients with CKD die of CVD than of the progression of kidney failure.The increase of homocysteine level, referred as hyperhomocysteinemia, is highly prevalent in CKD patients and associated with an increased risk of CVD complications. Proposed mechanisms for hyperhomocysteinemia in kidney failure is due to reduced clearance of total plasma homocysteine (tHcy) secondary to defective kidney and/or extra kidney metabolism of tHcy and deficiencies of folate, vitamin B12, and pyridoxal 5-phosphate (PLP). Aim-To study Serum Homocysteine levels in patients with Chronickidney disease and to estimate Serum Homocysteine levels in different stages of Chronic kidney disease. Materials And Methods- All the patients presenting with clinical, biochemical and ultrasound kidney evidence of chronic kidney disease in department of medicine at tertiary care centre in northern Maharashtra. Normal plasma homocysteine level was considered to bebelow 15 umol/litre. Results- A study of 54 patients with Chronic Kidney disease of both sex were taken as sample. Of the 54 patients 38 were males and 16 were females .36 patients were in age range of 41-60 . 32 patients were in stage 5 CKD , 14 were in stage 4 CKD , 8 were in stage 3 CKD. Hyperhomocysteinemia was observed in 78 % of CKD patients. Serum Homocysteinemia levels were maximum in patients with higher grade of CKD. The associationbetween decreased GFR and increase in serum homocysteine levels was found to be statistically significant. (p&lt;0.05). Conclusion-Study concludes that hyperhomocysteinemia is highly prevalent in CKD patients. Homocysteine is commonly considered as toxicthrombogenic amino acid which causes atherosclerosis and cardiovascular diseases. Mortality due to cardiovascular diseases is high in CKD. Hence early screening and treatment for Hyperhomocysteinemia should be done in CKD to prevent cardiovascular diseases.

Serum Homocysteine Level in Patients of Type 2 Diabetes Mellitus with Macrovascular Complications

The risk of CVD in men with DM is 3-fold and in women with DM 5-fold in comparison to those without diabetes(1). Diabetes is a recognized independent risk factor for stroke and is associated with higher morbidity and mortality(2-4). The severity and duration of DM are important predictors of both the incidence and the extent of PAD, as observed in United Kingdom Prospective Diabetes Study, where each 1% increase in glycosylated hemoglobin was correlated with a 28% increase in incidence of PAD, and higher rates of death, microvascular complications and major amputation.(5,6) Homocysteine concentration is found to be higher in patients with peripheral vascular, cerebrovascular and coronary artery diseases than those without such diseases.(7) This observational comparative study was done at Ramakrishna Care Hospital, Raipur, from January 2017 to June 2018 involving 100 type 2 diabetes mellitus patients. Patients were divided into two groups- Group 1: The Case Group- Type 2 DM patients with macrovascular complications. Group 2: The Control Group - Type 2 DM patients without any macrovascular complications With the help of Clinical evaluation and detailed investigations we had determined the presence of macrovascular complications in which we had included Myocardial infarction, CVA and Peripheral vascular disease. Data obtained from these patients were analysed and the results were compared with prior studies of similar objectives. Higher age and duration of diabetes thus had a positive correlation with macrovascular disease. The mean serum homocysteine level was statistically significant and they correlate with higher incidence of macrovascular disease in males and with increasing age. Keywords: Type 2 Diabetes Mellitus, DM, CVD, CVA, Serum Homocysteine Level, Macrovascular Complications.

Association of serum homocysteine levels with the development of preeclampsia

Aims: To determine the association between serum homocysteine levels and preeclampsia and its relevance as a potential marker for predicting preeclampsia.&#x0D; Methods: A total number of 50 preeclampsia cases were taken. 30 cases of normal pregnancy were taken as controls. This study was carried out in the Department of Obstetrics and Gynecology, Gauhati Medical College and Hospital, Gauahati from August 2012 to July 2013. Blood samples were drawn from the antecubital vein and serum homocysteine levels were measured.&#x0D; Results: The mean serum homocysteine levels in preeclampsia cases were 27.7 ± 6.4 μmol/l compared to serum homocysteine levels in normal pregnancy 9.23 ± 3.4 μmol/l (P&lt;0.01).There was a significant relationship between the systolic and the diastolic blood pressure and serum homocysteine levels. As the systolic and diastolic blood pressure increases, serum homocysteine levels also increased significantly (P&lt;0.001).&#x0D; Conclusion: This study showed raised serum homocysteine levels in patients with preeclampsia compared to normal pregnancy.&#x0D; Keywords: Serum homocysteine; Preeclampsia; Blood pressure

Assessment of lipid peroxidation, antioxidant enzyme superoxide dismutase, glutathione and serum homocysteine level in patients with polycystic ovary syndrome in Sudan Khartoum state

Polycystic ovary syndrome (PCOS) is a common health problem that affects teenage girls and young women. PCOS is associated with a wide spectrum of complications in various parts of health, including reproductive, metabolic and psychological features. Analytical case control study was conducted to Assessment of Lipid peroxidation, antioxidant enzyme Super oxide dismutase, Glutathione and Serum Homocysteine level in Patients with (PCOS) in Khartoum State. A total of three hundred individuals were enrolled in this study, and classified into two groups, two hundred patients with (PCOS) as test group and hundred healthy individuals as control group, the samples were used to measure Homocysteine, Glutathione, Lipid peroxidation and superoxide dismutase level in the serum of participant with increased body mass index in study group and normal body mass index. The results were expressed as (mean ± SD).The mean ± standard deviation of the total glutathione was found mean 1174.5±271.5 and the reduced glutathione was (801.30 ±132.2), and for superoxide dismutase mean ± standard deviation (225.2, ± 57.8) in study group while in control group found 195.5, ± 25.6 respectively, Homocysteine mean ± standard deviation (14.9, ± 2.1) for test group and (12.1, ± 2.5) for control group. Lipid peroxidation mean ± standard deviation was found 3.4± 1.1 for test group and control group (2.4 ± 0.7) respectively. The present study has conculcated that mean of serum homocysteine, glutathione, lipid peroxide and superoxidase concentrations were increased in women with (PCOS), could be a dilemma for many women of reproductive ages irrespective of their reproductive disorders.

Assessment of lipid peroxidation, antioxidant enzyme superoxide dismutase, glutathione and serum homocysteine level in patients with polycystic ovary syndrome in Sudan Khartoum state

Assessment of lipid peroxidation, antioxidant enzyme superoxide dismutase, glutathione and serum homocysteine level in patients with polycystic ovary syndrome in Sudan Khartoum state

To Evaluate the Association of Stress with Serum Cortisol and Serum Homocysteine Levels in Patients of Central Serous Chorioretinopathy

To Evaluate the Association of Stress with Serum Cortisol and Serum Homocysteine Levels in Patients of Central Serous Chorioretinopathy

Serum Homocysteine Level in Patients with Cerebral Venous Sinus Thrombosis (CVST): Relation to Initial Thrombosis Severity and Outcome

Serum Homocysteine elevation, has been observed in some cerebral vinous sinus thrombosis patients. There is a complex overlap between homocysteine level and cerebrovascular disease, and the cause and significance of homocysteine rise in cerebral vinous sinus thrombosis are still controversial.To detect serum homocysteine level in patients with cerebral venous sinus thrombosis and its impact on its severity, short term outcome, size of thrombosis. In this case control study, sixteen patients of CVST (13 males & 3 females) and 35 matched control subjects were recruited for this study. Serum homocysteine level was estimated by Enzyme-Linked Immunosorbent Assay (ELISA). Assessment of severity of thrombosis was done based on Canadian Neurological Scale. Assessment of outcome on discharge was done based on Barthel index score. In this study serum homocysteine level was raised in Cerebral Vinous Sinus Thrombosis cases when compared to controls on admission. The mean and standard deviation of homocysteine were 42.5 ± 54.2I¼mol/l in cases with significant p value of < 0.05. Cases with high homocysteine levels had low severity scores, which indicate poor prognosis. Homocyteine elevation in cerebral vinous sinus thrombosis (CVST) patients was associated with CT changes, severe thrombosis, large thrombus size and bad outcome.

The frequency of Raynaud’s phenomenon in patients with methylenetetrahydrofolate reductase gene mutation and hyperhomocysteinemia

Background/aimRaynaud’s phenomenon (RP) is not a rare health problem; global prevalence is about 3%–20%. Etiology and pathophysiology of this pathology has not been clarified. There are many precipitating factors resulting in RP. Hyperhomocysteinemia resulting from methylenetetrahydrofolate reductase (MTHFR) gene mutation may have a role in its etiology. The aim of this study was to observe the frequency of RP in patients with MTFHR gene mutation and hyperhomocysteinemia. Possible relationships among vitamin B12, folic acid, complete blood count (leukocytes and platelets), and c-reactive protein levels and RP were also analyzed.Materials and methodsA total of 388 patients admitted to the internal medicine, hematology, and obstetric clinics of a university hospital between January 2012 and April 2013 ranging in age from 21 to 83 (mean age 38.16 ± 13.1) were enrolled in the study. Eighty-five (21.9%) of the patients were male and 303 (78.1%) were female. MTHFR gene mutation was analyzed in 388 patients; 52 (13.4%) were homozygous, 275 (70.9%) were heterozygous, and 61 (15.7%) were found to be negative for the MTHFR gene mutation and accepted as a control group. Vitamin B12, folic acid, complete blood count (leukocytes and platelets), and c-reactive protein levels were also analyzed.ResultsHomocysteine levels were higher in both heterozygous and homozygous groups (P < 0.05). RP was more frequently observed in patients with elevated homocysteine levels (P < 0.05; X2 = 14.51). There was no significant relationship in other parameters studied.ConclusionRP was more frequently observed in the groups with the MTHFR mutation and hyperhomocysteinemia. Serum homocysteine levels in patients with RP may be helpful for diagnosis.

Serum homocysteine levels in patients with retinal vein occlusion

Purpose: To find out role of high serum homocysteine levels in retinal vein occlusion patients at Dr. D.Y. Patil medical College. Design: A matched case control type of study was conducted from 2016 to 2018. Materials and Methods: Total serum homocysteine (tHcy) was measured in patients coming at Dr. D.Y. Patil medical college, aged 20 years and above. We evaluated the presence of high homocysteine levels in patients with retinal vein occlusion. We evaluated serum homocysteine levels in 50 patients with retinal vein occlusion coming to our clinic. Control subjects consisted of age and sex matched patients that were referred to our clinic for retinal disease other than vascular occlusion. homocysteine levels between 4 µmol/L to 15 µmol/L were considered normal. High homocysteine level was defined as a total serum homocysteine level above 15 µmol/L. Results: The mean serum homocysteine level were 13.80+/-8.08 µmol/L (range, 4–33 µmol/L) for cases, and 6.43+/-1.38 µmol/L (range, 4–10 µmol/L) for controls. The mean serum homocysteine levels in cases were more than double that of controls. This difference was very highly statistically significant. Out of the 50 patients with retinal vein occlusion, 13 (26.00%) patients had serum homocysteine levels above normal levels as compared to the controls where none out of the 50 patients had homocysteine levels above normal. (Chi square = 14.94, d.f.=1, p in both cases and control groups. Conclusion: High homocysteine levels is a statistically significant risk factor for retinal vein occlusion and it should be evaluated in every patient with retinal vein occlusion. Keywords: Hyperhomocysteinemia, Retinal vein occlusion.

The serum homocysteine level in patients with acute ischemic stroke (AIS) after thrombolysis and its relationship with clinical outcomes.

The present study aims to investigate whether hyperhomocysteinemia (HHcy) affects the outcomes of the thrombolytic treatment for patients with AIS. A sample of 120 AIS patients were recruited and grouped according to their serum homocysteine (Hcy) levels. The National Institute of Health Stroke Scale (NIHSS) was obtained before treatment and 7 days after it to evaluate neurological outcomes; modified Rankin Scale (mRS) was obtained 12 weeks later to assess functional outcomes. Receiver operating characteristic curve (ROC) was used to demonstrate the relationship between serum Hcy level and the outcomes after tPA treatment. The serum Hcy level of 120 patients was of 27.57±20.17μmol/L. The NIHSS scores of the patients in the low Hcy level group were remarkably lower compared to those in the high-level group (p<0.05), after 7 days of treatment. In addition, the mRS scores of the patients in the low Hcy level group, after 12 weeks, were remarkably lower compared to those in the high-level group (p<0.01). ROC demonstrated that the serum Hcy level is related to the clinical outcomes of thrombolytic treatment with moderate specificity (80.3%) and sensitivity (58.2%). In conclusion, higher serum Hcy levels can indicate poorer clinical outcomes of thrombolytic treatment in patients with AIS.

Serum Homocysteine Levels in Patients with Retinal Vein Occlusion in a Spanish Population

The mean age of patients was 7 years older compared to the gold standard. Throughout surgery, mydriasis was smaller by 0.5-0.7 mm and was unaffected by tamsulosin use or iris colour. Age and pre-operative mydriasis with G tropicamide 1% significantly explained most of the variation in pupil diameter prior to capsulorhexis (p < 0.05). All patients requiring mechanical pupil dilation had pupils that dilated to less than 5 mm pre-operatively. The visual results and complication profiles matched that of the reference standard.

Evaluation of Serum Homocysteine Levels in Patients with Cutaneous-Oral Lichen Planus and Psoriasis Patients

Background: An elevated plasma homocysteine level is suggested to be a risk factor for reversible atherosclerotic cardiovascular disease. Psoriasis and lichen planus are two chronic inflammatory skin diseases associated with an increased risk of thrombosis and cardiovascular disease. Materials and Methods: We conducted this descriptive analytical study in 2015 on 30 psoriatic patients and 30 patients with cutaneous-oral lichen planus (selected via a simple randomized method) who were referred to the outpatient department of dermatology at Bouali Sina training and therapeutic hospital in Sari, Iran. We evaluated the serum homocysteine, vitamin B12, and folic acid levels in all patients. Data were evaluated using descriptive statistics and an independent t-test. Logistic regression was used for controlling confounding variables. Results: Nine (30%) patients in the psoriasis group and 11 (36.66%) in the cutaneous-oral lichen planus group had abnormally high blood homocysteine level (P = 0.001). Serum vitamin B12 level in the psoriatic group was significantly higher than in the cutaneous-oral lichen planus group (P = 0.034). Both mean and maximum serum folic acid levels in the psoriatic group were higher than in the cutaneous-oral lichen planus group, but the difference was not significant (P = 0.296). As psoriasis and cutaneous-oral lichen planus are chronic inflammatory skin diseases, in these groups, the serum homocysteine levels were higher than in healthy control subjects, but there was no significant differences between the two groups. Conclusion: Further studies are recommended about the course of treatment in patients with psoriasis and lichen planus diseases before therapeutic intervention. [GMJ.2017;6(3):226-232] DOI: 10.22086/gmj.v0i0.749

Diagnostic value of serum homocysteine level in patients with colon cancer

Objective To investigate the diagnostic value of serum homocysteine in the diagnosis of colon cancer. Methods The performance rate method was used to detect the level of serum homocysteine(Hcy) in colon cancer group(50 cases) who were treated in Beijing Tiantan Hospital Affiliated to Capital Medical University from March 2011 to June 2016 and control group(50 cases). The expression of independent samples t test was used to analysis of the difference of the Hcy levels between the two groups.The ROC curve was used to evaluate the value of Hcy in diagnosis of colon cancer. Results The serum Hcy level in colon cancer group was (18.6±8.9) μmol/L, in healthy control group was (10.7±4.3) μmol/L, colon cancer group serum Hcy levels were significantly higher than those of healthy control group, there was significant difference(t=5.627, P<0.01). AUC of ROC curve was 0.775, cut-off value of 18.5 μmol/L, sensitivity was 0.50, specificity was 0.94, 95%CI was 0.682-0.868(P<0.01). Conclusion Serum Hcy can be used as a reference index of the diagnosis of colon cancer. Key words: Homocysteine; Colon cancer; Tumor marker; ROC curve

Serum Homocysteine Levels in Patients with Retinal Vein Occlusion in a Spanish Population

Our aim was a) to compare serum Hcy levels in patients with RVO and population-based controls, and b) to evaluate whether hyperhomocysteinemia is a risk factor for RVO.Prospective case-control study of all patients diagnosed with RVO at a tertiary-care hospital, and age-and sex-matched controls taking part in a population-based prospective cohort in the same geographic area. Differences in serum Hcy between both groups were analyzed by a general linear model adjusted for age, body mass index (BMI), glomerular filtration rate (GFR), hypertension, dyslipidemia, diabetes, tobacco use and alcohol intake. Besides, we tested the relationship between hyperhomocysteinemia (> 15 µmol/L) and RVO, by a stepwise logistic regression analysis.

Serum levels of homocysteine, asymmetric dimethylarginine and nitric oxide in patients with Parkinson’s disease

Objectives: Endothelial dysfunction has been implicated as a crucial event in the development of several neurodegenerative diseases. The aim of this study was to investigate the serum homocysteine, asymmetric dimethylarginine (ADMA) and nitric oxide (NO) levels in patients with Parkinson’s disease (PD) and to compare the results with data from healthy controls.Methods: A total of 132 subjects, including 82 idiopathic PD patients who were newly diagnosed and untreated (47 males, 35 females, mean age of 60.8 ± 7.1 years) and 50 healthy controls (28 males, 22 females, mean age of 60.2 ± 6.7 years) were enrolled in this study. The serum ADMA and NO levels were determined using enzyme-linked immunosorbent assay (ELISA), while the homocysteine levels were determined by chemiluminescent microparticle immunoassay.Results: The ADMA and NO levels of the PD patients were significantly higher than those of the healthy controls. The serum ADMA levels were 0.70 ± 0.15 μmol/L in the PD patients and 0.50 ± 0.12 μmol/L in the healthy controls (p < 0.001). The serum NO levels were 78.7 ± 10.3 μmol/L in the PD patients and 59.9 ± 9.5 μmol/L in the healthy controls (p < 0.001). In addition, the ADMA and NO levels were significantly correlated with the serum homocysteine levels in patients with PD (r = 0.874, p < 0.001, r = 0.803, p = 0.005, respectively).Conclusion: In our study, the high ADMA and NO levels of patients with PD indicate endothelial dysfunction, and this dysfunction may play a role in PD pathogenesis. Larger studies, including randomised clinical trials in humans and animal studies, are needed to validate our findings and help in developing a better understanding of the pathogenesis of PD.

Effect of body weight on serum homocysteine level in patients with polycystic ovarian syndrome: A case control study

Polycystic ovarian syndrome (PCOS) represent one of the common endocrine disorders which influence around 8% of reproductive women whom usually suffering from obesity and increase cardiovascular risk. Serum homocysteine levels are associated with bad impact on endothelial functions and considered as an independent risk factor for cardiovascular disease. The aim was to study the level of plasma homocysteine in obese and non-obese Iraqi patients with PCOS. This study was carried out on 207 women. Of theme, 101 women with PCOS and 106 PCOS- free women served as controls. Blood sample was taken from each participant on the 2(nd) day of menstruation morning after an overnight fasting. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), free testosterone and androstenedione were measured. Moreover, total lipid profile and plasma homocysteine levels were measured in both groups. Sixty percent of PCOS women were overweight or obese and 56% of them had a waist circumference >88cm. Moreover plasma homocysteine concentrations were found to be higher in patients with PCOS (11.5±5.41μmol/L) as compared with control (8.10±1.89 μmol/L) (p<0.002). Furthermore the homocysteine concentrations were 13.19±5.97 μmol/L and 9.38±2.99 μmol/L in both obese and normal-weight PCOS women respectively which was significantly higher than obese (p<0.002) and normal-weight (p<0.004) control women. Increase in body weight is not an independent risk factor to increase plasma homocysteine levels in PCOS women.

The influence of Helicobacter pylori infection on serum homocysteine level in patients with carotid atherosclerosis

The influence of Helicobacter pylori infection on serum homocysteine level in patients with carotid atherosclerosis

Assessment of serum homocysteine level in patients with nonsegmental vitiligo

Aim To evaluate the serum level of homocysteine in non-segmental vitiligo cases compared to controls and its relation to the progression of the disease. Subjects and methods Serum Hcy levels were assessed in 40 patients diagnosed with non-segmental vitiligo (active and stable) in comparison to 40 age and sex matched healthy controls, using enzyme immunoassay technique (EIA). Relation to disease clinical phenotype, extent, severity and progression was assessed. Results An insignificantly higher level of serum homocysteine was detectable in vitiligo patients compared to controls. Patients with progressive disease had significantly higher levels than those with stable course. No significant relation was found to clinical phenotype, extent or clinical severity of the disease. Conclusion Hyperhomocysteinemia cannot be considered as a risk factor for development of non-segmental vitiligo, but it contributes to its activity and progression. It is not related to disease clinical phenotype, extent or severity.

The serum homocysteine levels in patients with first-episode depression and its relationship with P300

Objective To study the relationship between the serum homocysteine （ Hcy ） levels in patients with first-episode depression and event related potentials （ ERP ） P300.Methods 117 first-episode depressive patients were selected as the case group,and 110 healthy volunteers were selected as the health control group,the de-termination of serum Hcy levels in the two groups were detected by enzyme linked immunosorbent assay,measured by the Shenzhen Brain Master brain evoked potential system to complete the visual P300.Results The serum Hcy levels of the case group was （14.0 ±9.8）μmol/L,which was higher than （10.5 ±7.5）μmol/L of the health control group （t=-3.087,P 〈0.05）.The N1,N2 incubation period of the case group were （91.4 ±18.6） ms,（235.4 ± 30.5）ms,respectively,which were longer than （88.6 ±13.0）ms,（204.3 ±20.3）ms of the health control group（t=1.305,8.990,all P〈0.01）;The P3 incubation period of the case group were （359.5 ±30.0）ms,which was longer than （327.2 ±41.8）ms of the health control group（t=6.685,P〈0.05）.The target P3,non-target P2 amplitude of the case group were （4.1 ±2.0）μV,（4.2 ±1.9）μV,respectively,which were singnificantly lower than （6.8 ± 3.8）μV,（6.6 ±3.6） μV of the health control group（ t=-6.694,-6.485,all P〈0.01）.The P2 incubation period of Hcy case group was （194.4 ±13.6） ms,which was longer than （163.1 ±21.8） ms of the non Hcy case group（t=8.486,P〈0.01）.The P3 incubation period of Hcy case group was （357.0 ±24.5）ms,which was longer than （337.1 ±45.5）ms of the non Hcy case group（t=2.645,P〈0.05）.The target P3,non-target P2 amplitude of the Hcy case group were （5.4 ±1.5）μV,（5.2 ±1.2） μV,which were significantly lower than （5.8 ±3.8）μV, （5.4 ±3.2）μV of the Hcy case group（t=-0.745,-0.208,all P〈0.01）.Conclusion The serum Hcy levels in patients with first-episode depression increased, and P300 latency, amplitude decreased, the cognitive function is related to Hcy metabolism disorder and depression damage. Key words: Depressive Disorder Cysteine Event-Related Potentials; P300 Cognition