No effect of folic acid supplementation in the course of 1 year on haemostasis markers and C-reactive protein in older adults

Abstract

SummaryElevated homocysteine levels are associated with an increased cardiovascular disease (CVD) risk, but the underlying mechanism is still unclear. High homocysteine might affect the endothelium, and consequently lead to impaired haemostasis. In a randomized placebo controlled trial among 276 older adults with plasma total homocysteine concentrations above 13 mM at screening, we investigated the effect of homocysteine lowering by folic acid supplementation (0.8 mg/day) for 1 year on markers of endothelial function (vonWillebrand factor), coagulation (tissue factor, factor VIIa, fragments 1+2), and fibrinolysis (fibrin degradation products, tissue-type plasminogen activator), and inflammation (C-reactive protein). Despite a 24% reduction in plasma homocysteine concentration and four-fold increase in serum folate concentration in the folic acid group compared to the placebo group, there was no clear change in any of the haemostasis markers, nor CRP. Although homocysteine is associated with vascular disease risk in the general population, marked lowering of slightly elevated homocysteine concentrations by one-year folic acid supplementation does not influence haemostasis markers.

Influence of Folate Serum Concentration on Plasma Homocysteine Levels in HIV-Positive Patients Exposed to Protease Inhibitors Undergoing HAART

“…A unique study in HIV-positive patients demonstrated that supplementary treatment with folate-vitamin B 12 complex was effective in reducing Hcy, both in patients with hyper-Hcy and in those with Hcy considered to be normal [14] . Other studies, conducted in HIVnegative patients, did not confi rm the useful role of nutrient supplementation in inducing Hcy normalization [15] , or normalization of Hcy-related hemostasis markers [16] , while another reported that smoking cessation would reduce plasma Hcy levels [17] . Lastly, another study conducted in a HIV-negative population demonstrated a signifi cant reduction of Hcy; however, this did not correlate with normalization of coagulation markers associated with cardiovascular risk [18] and impact on reduction of cardiovascular events has not been demonstrated yet [19] .…”

Effect of supplementation with B vitamins and antioxidants on levels of asymmetric dimethylarginine (ADMA) and C-reactive protein (CRP): a double-blind, randomised, factorial design, placebo-controlled trial

“…Intervention studies carried out evaluating the effect of B vitamins on CRP concentrations have been conducted in subjects who were undergoing haemodialysis [53], or stable coronary artery disease patients [54], or those with hyperhomocysteinemia [55]. Two out of three reported no significant treatment effect on CRP levels [54,55].…”

“…Intervention studies carried out evaluating the effect of B vitamins on CRP concentrations have been conducted in subjects who were undergoing haemodialysis [53], or stable coronary artery disease patients [54], or those with hyperhomocysteinemia [55]. Two out of three reported no significant treatment effect on CRP levels [54,55]. However, Chang et al demonstrated that a 3-month intervention with a combined B vitamin supplement effectively lowered tHcy and CRP concentrations in haemodialysis subjects, although this study was a randomised, open-labelled study which used doses higher than those in this current study (folic acid (5 mg/d) and vitamin B complex) [53].…”

Das polyzystische Ovarsyndrom – Metabolische Konsequenzen

“…Dieser putative Marker findet sich bei PCOS-Patientinnen erhöht und korreliert mit anderen Risikofaktoren [75] . Eine Erhöhung des Homozysteins scheint mit dem Auftreten von CVD assoziiert zu sein, wobei der Nutzen einer therapeutischen Intervention mit Folsäure nicht belegt ist [76] . Einige Studien berichten über eine Erhö-hung des Homozysteins bei PCOS-Patientinnen mit einer Korrelation zur Insulinresistenz [77] .…”