Effect of folic acid supplementation on the progression of carotid intima-media thickness: A meta-analysis of randomized controlled trials
ABSTRACT We conducted a meta-analysis of relevant randomized trials to assess whether folic acid supplementation reduces the progression of atherosclerosis as measured by carotid intima-media thickness (CIMT).
This analysis included 2052 subjects from ten folic acid randomized trials with the change in CIMT reported as one of the end points. Summary estimates of weighted mean differences (WMDs) and 95% CIs were obtained by using random-effect models. Meta-regression and subgroup analyses were performed to identify the source of heterogeneity.
Our analysis showed that folic acid supplementation significantly reduces the progression of CIMT (WMD: -0.04 mm; 95%CI: -0.07, -0.02; P<0.001), particularly in subjects with chronic kidney disease (CKD) (WMD: -0.16 mm; 95%CI: -0.26, -0.07; P=0.0006) or high cardiovascular disease (CVD) risk (WMD: -0.05 mm; 95%CI: -0.11, 0.00; P=0.06) but not in subjects who were generally healthy with only elevated homocysteine concentrations (WMD:0.00 mm; 95%CI: -0.01, 0.01; P=0.35). Furthermore, meta-regression analysis of the data showed that the baseline CIMT levels (P=0.011) and the percent reduction of homocysteine (P<0.001) were positively related to the effect size. Consistently, a greater beneficial effect was seen in those trials with baseline CIMT levels ≥0.8 mm (WMD: -0.14 mm; 95%CI: -0.19, -0.08; P<0.0001), and a reduction in the homocysteine concentration ≥30% (WMD: -0.22 mm; 95%CI: -0.38, -0.06; P=0.009). In the corresponding comparison groups, the effect sizes were attenuated and insignificant.
Our findings indicate that folic acid supplementation is effective in reducing the progression of CIMT, particularly in subjects with CKD or high CVD risk and among trials with higher baseline CIMT levels or a larger homocysteine reduction.
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ABSTRACT: We aimed to investigate the prevalence of hyperhomocysteinaemia (total plasma homocysteine (tHcy) ≥ 10 μmol/l) and its major determinants in rural Chinese hypertensive patients. A cross-sectional investigation was carried out in Lianyungang of Jiangsu province, China. This analysis included 13 946 hypertensive adults. The prevalence of hyperhomocysteinaemia was 51·6 % (42·7 % in women and 65·6 % in men). The OR of hyperhomocysteinaemia were 1·52 (95 % CI 1·39, 1·67) and 2·32 (95 % CI 2·07, 2·61) for participants aged 55-65 and 65-75 v. 45-55 years; 1·27 (95 % CI 1·18, 1·37) for participants with a BMI ≥ 25 v. < 25 kg/m2; 1·14 (95 % CI 1·06, 1·23) for participants with v. without antihypertensive treatment; 1·09 (95 % CI 1·00, 1·18) for residents inland v. coastal; 0·89 (95 % CI 0·82, 0·97) and 0·83 (95 % CI 0·74, 0·92) for participants with moderate and high v. low physical activity levels; 1·54 (95 % CI 1·41, 1·68) and 2·47 (95 % CI 2·17, 2·81) for participants with a glomerular filtration rate 60-90 and < 60 v. ≥ 90 ml/min per 1·73 m2; and 1·20 (95 % CI 1·07, 1·35) and 3·81 (95 % CI 3·33, 4·36) for participants with CT and TT v. CC genotype at methylenetetrahydrofolate reductase 677C>T polymorphism, respectively. Furthermore, higher tHcy concentrations were observed in smokers of both sexes (men: geometric mean 12·1 (interquartile range (IQR) 9·2-14·5) v. 11·9 (IQR 9·3-14·0) μmol/l, P = 0·005; women: geometric mean 10·3 (IQR 8·3-13·0) v. 9·6 (IQR 7·8-11·6) μmol/l, P = 0·010), and only in males with hypertension grade 3 (v. grade 1 or controlled blood pressure) (geometric mean 12·1 (IQR 9·2-14·4) v. 11·7 (IQR 9·2-14·0), P = 0·016) and in male non-drinkers (yes v. no) (geometric mean 12·3 (IQR 9·4-14·8) v. 11·7 (IQR 9·1-13·9), P = 0·014). In conclusion, there was a high prevalence of hyperhomocysteinaemia in Chinese hypertensive adults, particularly in the inlanders, who may benefit greatly from tHcy-lowering strategies, such as folic acid supplementation and lifestyle change.The British journal of nutrition 07/2012; DOI:10.1017/S0007114512003157 · 3.34 Impact Factor
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ABSTRACT: The association between diet and CVD cannot be assigned to a single nutrient, but rather to a set of nutrients and non-nutrients, and eating pattern analyses have become an important tool in investigation of this relationship. Our objective was to investigate eating patterns in relation to nutrient intake and serum concentration of folate, vitamin B12 and TAG in ninety-five healthy adult participants. Dietary information was collected by an FFQ, and eating patterns were obtained by principal components analyses of thirty-three food groups. Three eating patterns were extracted, a sweet eating pattern identified by intakes of cakes, snacks, sugar-sweetened drinks and chocolates; a prudent eating pattern identified by vegetables, fruits and olive oil; and a traditional food pattern identified by red meat, lean fish and cheese. Blood samples were collected in the morning after an overnight fast. Linear regression analyses adjusted for age, BMI and smoking showed a negative association between the sweet eating pattern scores and the serum concentration of folate (β = −2·31 (95 % CI −4·14, −0·45)) and a positive association with serum concentration of TAG (β = 0·35 (95 % CI 0·12, 0·57)). The prudent eating pattern scores were positively associated with the serum concentration of folate (β = 1·69 (95 % CI 0·44, 2·92)). In conclusion, a sweet eating pattern was associated with risk factors for CVD, whereas a prudent eating pattern was associated with protective factors.08/2012; 1. DOI:10.1017/jns.2012.8
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ABSTRACT: The protonation equilibria of vitamin B9 (folic acid) was studied at 298.15 K in a different water–dioxane mixtures [100 wdioxane = 20 %, 40 %, 60 %, and 80 %] with an ionic strength of 0.15 mol·dm–3 NaNO3. The influence of dioxane content on the protonation processes was explained. Also, four protonation constants have been determined in 60 % dioxane with an ionic strengths of (0.15, 0.20, 0.25, and 0.30) mol·dm–3 NaNO3 using the pH-potentiometric technique. HYPERQUAD 2008, a program based on nonlinear least-squares curve fitting was used to determine these four stepwise protonation constants of folic acid from the analysis of pH-potentiometric data. From the determined protonation constants, the representative folate species distribution diagrams were provided by HYSS 2009 program and discussed.Journal of Chemical & Engineering Data 07/2013; 58(8):2219–2223. DOI:10.1021/je4002569 · 2.05 Impact Factor