vitamin-b-12 and Carotid-Artery-Diseases

The aim of this study was to compare the sensitivity of three ultrasound phenotypes of carotid atherosclerosis in a longitudinal study of patients with diabetic nephropathy. B-mode ultrasound-derived intima-media thickness (IMT), total plaque area (TPA) as well as three-dimensional ultrasound (3DUS) vessel wall volume (VWV) of the common carotid artery (CCA) (VWV(CCA)) and internal carotid artery (ICA). (VWV(CCA+ICA)) were all evaluated in subjects enrolled in a randomized placebo-controlled double blind study of vitamin B therapy. Of 106 subjects randomized, 77 subjects were scanned at baseline and 2.3 +/- 1 y later (range: 0.5 to 4.5 y); of these subjects, 71 had images of sufficient quality for complete analysis of all three measurements. Subjects were analyzed according to the two treatment groups (A and B) and the analysis was performed blinded to treatment group description to prevent any potential for bias in future analyses. There were differences in sensitivity to longitudinal changes observed in all the ultrasound measurements. Specifically, there was no difference in IMT change between treatment groups (0.02 +/- 0.07 mm/y and 0.02 +/- 0.1 mm/y p = 0.15, group A and B, respectively, rates not different from zero [p > 0.05]) or TPA rate between treatment groups (0.09 +/- 0.2 cm(2)/y, significantly different from 0, p = 0.013 and -0.02 +/- 0.3 cm(2)/y in group A and B, respectively). However, the VWV(CCA+ICA) rate of change was significantly greater than 0 for group B (53 +/- 110 mm(3)/y) (p = 0.008), which was significantly (p = 0.034) higher than the rate of change of VWV(CCA+ICA) (nonsignificant, p = 0.6) for group A (-12 +/- 137 mm(3)/y). The relationship between DeltaVWV and DeltaIMT was significant, such that in group A, DeltaVWV(CCA) was positively associated with DeltaIMT (r = 0.44, p < 0.05), and in group B, DeltaVWV(CCA) was negatively correlated with DeltaIMT (r = -0.44, p < 0.01). These results suggest that 3DUS-derived VWV provides necessary and sufficient sensitivity and specificity to measure longitudinal changes in small numbers of carotid atherosclerosis patients at risk of disease progression and over short periods of time.

Topics: Aged; Carotid Artery Diseases; Carotid Artery, Common; Carotid Artery, Internal; Diabetic Angiopathies; Diabetic Nephropathies; Disease Progression; Double-Blind Method; Drug Combinations; Female; Humans; Image Interpretation, Computer-Assisted; Imaging, Three-Dimensional; Longitudinal Studies; Male; Middle Aged; Tunica Intima; Tunica Media; Ultrasonography; Vitamin B 12; Vitamin B 6

Homocysteine has been proposed as a risk factor for atherosclerosis. The association between plasma total homocysteine (tHcy) concentration and carotid atherosclerosis has not been thoroughly studied in high-risk populations with vascular disease. For this study, carotid atherosclerosis was assessed by measurements of carotid intima-media thickness (IMT) and plaque calcification in 923 patients with vascular disease or diabetes. Associations with tHcy and plasma folate concentrations were examined. The mean and single maximum carotid IMT were 1.27 +/- 0.34 mm and 2.41 +/- 0.83 mm, respectively. The mean segment plaque calcification score was 27.8%. tHcy correlated with mean (r = 0.13; p < 0.001) and single maximum (r = 0.12; p < 0.001) carotid IMT. There was a progressive increase in mean and single maximum carotid IMT across quartiles of tHcy (p < 0.0001 for trend). These associations were no longer significant after adjusting for other CV risk factors. A trend towards an inverse association between plasma folate and mean max carotid IMT was found in both univariate and multivariable analyses. However, the plaque calcification score increased across quartiles of tHcy (p < 0.01) and decreased across quartiles of plasma folate concentrations (p < 0.05) after multiple adjustments. In conclusion, in high-risk individuals, tHcy and low folate concentrations were only weakly associated with carotid IMT. In contrast, we found an independent association with the plaque calcification score, a measure of more advanced atherosclerosis. The effect of tHcy lowering on carotid atherosclerosis and stroke prevention warrants further investigation.

Topics: Aged; Biomarkers; Calcinosis; Canada; Cardiovascular Diseases; Carotid Artery Diseases; Carotid Artery, Common; Disease Progression; Drug Combinations; Female; Folic Acid; Homocysteine; Humans; Male; Middle Aged; Prospective Studies; Risk Factors; Tunica Intima; Tunica Media; Ultrasonography; Vitamin B 12; Vitamin B 6; Vitamin B Complex

Plasma B-group vitamins and age may affect the carotid intima-media thickness (IMT) in subjects with different 677TT genotype of the methylenetetrahydrofolate reductase (MTHFR) gene.. A hospital-based cross-study.. Genomic and Vascular Center, Changhua Christian Hospital, Changhua, Taiwan.. Five hundred and forty-one clinically healthy subjects.. Fasting plasma, homocysteine (Hcy), vitamin B(6), vitamin B(12), folate and B-mode carotid ultrasound.. MTHFR genotype, plasma concentrations of folate, vitamin B(6) and vitamin B(12) and age were significantly correlated to the plasma Hcy concentration. MTHFR 677TT carriers had higher concentrations of Hcy than did subjects with the CC and CT genotypes. Age, sex, body mass index and plasma Hcy were independent contributors to increase carotid IMT. However, with stratification by mean value of age and B-group vitamins concentrations, we found that at advanced age, lower plasma folate and vitamin B(12) were three risk factors involved in the enhancing effect of the MTHFR 677TT genotype on the increase of plasma Hcy and carotid IMT.. MTHFR 677TT-related carotid atherosclerosis was only identified in healthy elderly subjects with lower level of plasma folate and vitamin B(12).. Changhua Christian Hospital.

Topics: Adult; Age Factors; Aged; Aged, 80 and over; Carbon-Nitrogen Ligases; Carotid Arteries; Carotid Artery Diseases; Cross-Sectional Studies; Female; Folic Acid; Genotype; Homocysteine; Humans; Male; Middle Aged; Polymorphism, Genetic; Risk Factors; Sex Factors; Tunica Intima; Vitamin B 12; Vitamin B Complex

Topics: Aged; Aortic Aneurysm, Abdominal; Atherosclerosis; Carotid Artery Diseases; Folic Acid; Genotype; Homocysteine; Humans; Ischemia; Leg; Male; Methylenetetrahydrofolate Reductase (NADPH2); Peripheral Vascular Diseases; Risk Factors; Vitamin B 12

To explore the relationship between the carotid artery atherosclerosis (CAA) and the level of homocysteine (Hcy) as well as folate, vitamin B(12) and lipids.. The diameter of common carotid arteries and internal carotid arteries on both sides were measured by B-mode ultrasound in 126 subjects who were divided into normal and A, B, C, D groups according to the severity of stenosis of CAA. With fasting serum, Hcy as well as folate, vitamin B(12), triglycerides, total cholesterols (TC), low density lipid (LDL), high density lipid (HDL) were detected.. When stenosis of CAA became severer, serum Hcy was higher. The levels of the normal and A, B, C, D groups were (13.22 +/- 6.15, 16.29 +/- 9.81, 19.49 +/- 11.16, 27.21 +/- 17.47, 24.14 +/- 8.64) micromol/L, respectively. Rank test showed a significant difference between the normal and other groups (P < 0.01). Folic acid and VitB(12) were negatively correlated with the Hcy concentrations. Spearman correlation coefficient were -0.23 and -0.42 (P = 0.000). According to the severity of stenosis of CAA, Hcy, age, weight, blood pressure, level of glucose, triglyceride, TC, LDL, high density lipid (HDL) and history of hypertension, diabetes, heart disease and stroke were brought into logistic analysis; the result showed that Hcy, TC, HDL had significant negative correlation with the severity of CAA, Spearman correlation coefficient were 0.56, 0.25 and 0.22 (P = 0.003, 0.02, 0.04).. Hyperhomocysteinaemia is an independent risk factor of CAA and the severity of stenosis of CAA is highly correlated with Hcy concentration. The causes of hyperhomocysteinaemia may be the results of decrease of folate and VitB(12) levels. Clinical trials are now required to evaluate the effect of treatment with these vitamins in the primary and secondary prevention of vascular diseases.

Topics: Adult; Aged; Aged, 80 and over; Carotid Artery Diseases; Female; Folic Acid; Homocysteine; Humans; Hyperhomocysteinemia; Lipids; Male; Middle Aged; Risk Factors; Vitamin B 12

Elevated levels of plasma homocysteine (Hcy), a risk factor for coronary artery disease (CAD), can result from genetic errors, e.g., the methylenetetrahydrofolate reductase (MTHFR) polymorphism, or nutritional deficiencies, e.g., in vitamin B12 and folate. The mechanism by which Hcy induces atherosclerosis is not fully understood. Recently, Hcy has also been observed to induce DNA damage. In this study, we have investigated whether DNA damage is related to the C677T variant in the MTHFR gene and to plasma levels of Hcy, B12, and folate in patients with CAD. Patients ( n=46) with angiographically proven CAD were studied by using the micronucleus (MN) test, an accepted method for evaluating genetic instability. TT patients had plasma Hcy levels higher than those with the CT or CC genotypes (27.8+/-5.2 vs 13.7+/-2.2 and 12.9+/-1.9 micro mol/l, respectively; P=0.02). Patients with multi-vessel disease had higher plasma Hcy levels (11.6+/-1.2, 22.0+/-4.7, 19.3+/-3.9 micromol/l for one-, two- and three-vessel disease, respectively; P=0.05). The MN index increased with the number of affected vessels (8.4+/-0.7, 11.1+/-2.0, 14.2+/-1.7 for one-, two-, and three-vessels disease, respectively; P=0.02) and was significantly higher in subjects with the TT genotype compared with the CC or CT genotypes (15.7+/-2.4 vs 8.9+/-1.7 and 9.9+/-0.8; P=0.02). The MN index was also correlated negatively with plasma B12 concentration ( r=-0.343; P=0.019) and positively with plasma Hcy ( r=0.429, P=0.005). These data indicate that the MN index is associated with the severity of CAD and is related to the MTHFR polymorphism, suggesting an interesting link between coronary atherosclerosis and genetic instability in humans.

Topics: Aged; Alleles; Carotid Artery Diseases; Coronary Angiography; Cytosine; DNA; DNA Damage; DNA Mutational Analysis; DNA Primers; Female; Folic Acid; Genotype; Homocysteine; Humans; Male; Methylenetetrahydrofolate Reductase (NADPH2); Micronucleus Tests; Middle Aged; Oxidoreductases Acting on CH-NH Group Donors; Point Mutation; Polymerase Chain Reaction; Polymorphism, Genetic; Risk Factors; Thymidine; Vitamin B 12

The atherogenicity of homocyst(e)ine--H(e) --emerged from many studies showing an association between moderately elevated levels and vascular occlusive disease. The aim of this study was to evaluate whether high homocyst(e)ine levels were associated with carotid atherosclerosis. Carotid atherosclerosis was defined as an intimal media thickness of internal and carotid bifurcation of at least 2 mm on the near and far walls as determined by B-mode ultrasonography. The study population included 91 patients: group 1 (61% males, mean age 64+/-10 years, 57% with history of hypertension) with ultrasound evidence of carotid atherosclerosis and 100 with normal carotid walls--group 2 (36% males, mean age 52+/-15 years, 27% with history of hypertension). Homocyst(e)ine levels (mol/L) were determined by high-performance liquid chromatography with a fluorescent detector. Body mass index, dyslipidemia, smoking, diabetes, serum creatinine, plasma folic acid and vitamin B12 were not significantly different in the two groups. Homocyst(e)ine levels (micromol/L) were significantly higher in patients with carotid ather osclerosis than in those with normal arteries (11.7+/-6.5 micromol/L, 95% CI 10.4-13.1 vs 8.07+/-4.4 micromol/L, 95% CI 7.2-8.9, p<0.0001). By multiple regression analysis H(e) levels were positively correlated with male gender (p<0.02), age (p<0.001), and negatively with folic acid (p<0.0001). By logistic regression the independent predictors of carotid atherosclerosis were male gender (OR 2.65), hypertension (OR 2.55), age (x10 years, OR 2.15) and H(e) levels (x1 micromol/L, OR 1.11). This study confirmed homocyst(e)ine is associated with carotid atherosclerosis. Consequently the authors recommend H(e) levels be screened in all patients at risk for atherosclerosis.

Topics: Age Factors; Body Mass Index; Carotid Artery Diseases; Carotid Artery, Common; Carotid Artery, Internal; Chromatography, High Pressure Liquid; Creatinine; Diabetes Complications; Female; Fluorescence; Folic Acid; Homocysteine; Humans; Hyperhomocysteinemia; Hyperlipidemias; Hypertension; Logistic Models; Male; Middle Aged; Regression Analysis; Risk Factors; Sex Factors; Smoking; Tunica Intima; Tunica Media; Ultrasonography; Vitamin B 12

The data demonstrate that high plasma homocysteine levels and low plasma folate and vitamin B12 levels are associated with a higher prevalence of 40% to 100% extracranial carotid arterial disease (ECAD) in older men and women. Elevated plasma homocysteine levels were observed in 45% of the older men with 40% to 100% ECAD versus 20% of the older men with 0% to 39% ECAD, and in 40% of the older women with 40% to 100% ECAD versus 18% of the older women with 0% to 39% ECAD.

Topics: Aged; Aged, 80 and over; Carotid Artery Diseases; Female; Folic Acid; Homocysteine; Humans; Male; Prospective Studies; Risk Factors; Vitamin B 12

Topics: Adult; Carotid Artery Diseases; Carotid Artery, Internal; Female; Humans; Male; Middle Aged; Physical Therapy Modalities; Vitamin B 12