Background and Aims: HOMOCYSTEINE is a sulphur amino acid derived from methionine. Epidemiological studies show an association between hyperHOMOCYSTEINEmia and an increased cardiovascular risk, a fact that has also been confirmed in patients with chronic renal failure. This study, conducted in stage 5 chronic kidney disease patients, seeks to define the prevalence of hyperHOMOCYSTEINEmia, evaluate the clearance of HOMOCYSTEINE with dialysis, and describe the frequency of the mutation in the mutilen-tetrahydrofolate reductase enzyme and its relationship with plasma levels of HOMOCYSTEINE.Methods: The reduced percentage of HOMOCYSTEINE and clearance of urea were analysed every six months for seven years in patients on dialysis. Urea and total HOMOCYSTEINE in plasma were measured in each of these studies and the type of dialyser - low or high permeability - used and the dialysis duration was determined.A molecular study of the gene coding for mutilen-tetrahydrofolate reductase enzyme was carried out in a group of patients and any C-T point mutation at position 677 of this gene was investigated. Mutation was described as not present, heterozygous for this mutation or homozygous for lactation.Results: Neither the average levels of HOMOCYSTEINE before and after dialysis or the reduction percentage of HOMOCYSTEINE varied with gender, although purification of urea was higher in women. Comparisons of HOMOCYSTEINE levels and percentage reduction in this ratio according to the ultra filtration of the dialyser used showed significant results. The molecular study of the gene in mutilen-tetrahydrofolate reductase enzyme showed that mutation was present in 54.8%: 45.2% with heterozygous polymorphism and 9.7% with homozygous.Conclusions: Patients undergoing hemodialysis were found to have higher levels of urea and its clearance was greater with the higher the ratio of ultra filtration dialyser. Mutation of the gene in mutilen-tetrahydrofolate reductase enzyme was similar in our patients compared to the general population and had no impact on plasma levels of HOMOCYSTEINE.

Background: Elevated total plasma HOMOCYSTEINE, is an independent risk factor for cardiovascular disease. Folate and vitamin B12 have not only a protective effect on cardiovascular disease but also an essential effect on total HOMOCYSTEINE concentrations (tHcy). This survey has been conducted to evaluate the determinants of tHcy in 1191 healthy Iranian adults. Methods: This study which was a part of the Cardiovascular Risk Factors Survey in the Population Lab Region, has been designed and conducted based on MONICA/WHO project. A total of 1191 people have been recruited and assessed on serum HOMOCYSTEINE, Folic acid and vitamin B12, triglycerides, cholesterol, HDL-C, LDL-C, FBS, BMI, BP and smoking, with interview, questionnaires, examination and blood sampling. Blood samples were analyzed according to standard methods. Results: The variables were assessed in 1191 participants include 416 men (34.9%) and 775 women (65.1%). Prevalence of hyperHOMOCYSTEINEmia was correlated significantly with male sex and aging. Hcy levels were inversely related to serum Folate and vitamin B12 concentrations. After further adjustments, we detected a positive correlation between tHcy and age, male sex, smoking and BMI, and a negative one with LDL-C and diabetes. Although there was a correlation between tHcy and blood pressure, after age, sex, BMI and smoking adjustment, it just remained significant in women and with systolic blood pressure.         ‍Conclusion: We found that dietary and lifestyle parameters such as Folate intake and smoking habit are the main determinants of distribution of plasma HOMOCYSTEINE in an apparently healthy population. We assumed that lifestyle changes could have considerable subsequences in public health. Our findings confirm the potential advantages of dietary improvements and increased intake of nutrients along with smoking cessation in order to prevent cardiovascular diseases in high-risk patients.