Project description:BACKGROUND:Cardiovascular disease such as coronary artery disease, stroke and congestive heart failure, is a leading cause of death worldwide. A postulated risk factor is elevated circulating total homocysteine (tHcy) levels which is influenced mainly by blood levels of cyanocobalamin (vitamin B12), folic acid (vitamin B9) and pyridoxine (vitamin B6). There is uncertainty regarding the strength of association between tHcy and the risk of cardiovascular disease. OBJECTIVES:To assess the clinical effectiveness of homocysteine-lowering interventions (HLI) in people with or without pre-existing cardiovascular disease. SEARCH STRATEGY:We searched The Cochrane Central Register of Controlled Trials (CENTRAL) on The Cochrane Library (issue 3 2008), MEDLINE (1950 to August 2008), EMBASE (1988 to August 2008), and LILACS (1982 to September 2, 2008). We also searched in Allied and Complementary Medicine (AMED; 1985 to August 2008), ISI Web of Science (1993 to August 2008), and the Cochrane Stroke Group Specialised Register (April 2007). We hand searched pertinent journals and the reference lists of included papers. We also contacted researchers in the field. There was no language restriction in the search. SELECTION CRITERIA:We included randomised clinical trials (RCTs) assessing the effects of HLI for preventing cardiovascular events with a follow-up period of 1 year or longer. We considered myocardial infarction and stroke as the primary outcomes. We excluded studies in patients with end-stage renal disease. DATA COLLECTION AND ANALYSIS:We independently performed study selection, risk of bias assessment and data extraction. We estimated relative risks (RR) for dichotomous outcomes. We measured statistical heterogeneity using I(2). We used a random-effects model to synthesise the findings. MAIN RESULTS:We included eight RCTs involving 24,210 participants with a low risk of bias in general terms. HLI did not reduce the risk of non-fatal or fatal myocardial infarction, stroke, or death by any cause (pooled RR 1.03, 95% CI 0.94 to 1.13, I(2) = 0%; pooled RR 0.89, 95% CI 0.73 to 1.08, I(2) = 15%); and pooled RR 1.00 (95% CI 0.92 to 1.09, I(2): 0%), respectively. AUTHORS' CONCLUSIONS:Results from available published trials suggest that there is no evidence to support the use of HLI to prevent cardiovascular events.
Project description:ObjectiveTo systematically review the effect of folic acid based homocysteine lowering on cardiovascular outcomes in people with kidney disease.DesignSystematic review and meta-analysis.Data sourcesMedline, Embase, the Cochrane Library, and ClinicalTrials.gov to June 2011.Study selectionRandomised trials in people with non-dialysis dependent chronic kidney disease or end stage kidney disease or with a functioning kidney transplant reporting at least 100 patient years of follow-up and assessing the effect of folic acid based homocysteine lowering therapy. No language restrictions were applied.Data extractionTwo reviewers independently extracted data on study setting, design, and outcomes using a standardised form. The primary endpoint was cardiovascular events (myocardial infarction, stroke, and cardiovascular mortality, or as defined by study author). Secondary endpoints included the individual composite components, all cause mortality, access thrombosis, requirement for renal replacement therapy, and reported adverse events, including haematological and neurological events. The effect of folic acid based homocysteine lowering on outcomes was assessed with meta-analysis using random effects models.Results11 trials were identified that reported on 4389 people with chronic kidney disease, 2452 with end stage kidney disease, and 4110 with functioning kidney transplants (10,951 participants in total). Folic acid based homocysteine therapy did not prevent cardiovascular events (relative risk 0.97, 95% confidence interval 0.92 to 1.03, P = 0.326) or any of the secondary outcomes. There was no evidence of heterogeneity in subgroup analyses, including those of kidney disease category, background fortification, rates of pre-existing disease, or baseline homocysteine level. The definitions of chronic kidney disease varied widely between the studies. Non-cardiovascular events could not be analysed as few studies reported these outcomes.ConclusionsFolic acid based homocysteine lowering does not reduce cardiovascular events in people with kidney disease. Folic acid based regimens should not be used for the prevention of cardiovascular events in people with kidney disease.
Project description:Individuals with advanced chronic kidney disease (CKD) and end-stage renal disease (ESRD) have high plasma total homocysteine (tHcy) levels, which may be a risk factor for cognitive impairment. Whether treatment with high-dose B vitamins to decrease high tHcy levels improves cognition in persons with kidney disease is unknown.Randomized controlled trial.A substudy of 659 patients (mean age, 67.3 +/- 11.7 years) who participated in a randomized double-blind clinical trial 5 years in duration conducted in 36 US Department of Veterans Affairs medical centers of the effect on all-cause mortality of vitamin-induced lowering of plasma tHcy level. 236 (35.8%) were treated by using dialysis (ESRD) and 423 (64.2%) had a Cockcroft-Gault estimated creatinine clearance of 30 mL/min or less (advanced CKD). All had high tHcy levels (> or =15 micromol/L) at baseline. Cognitive assessments began during the follow-up period of the main trial 3 years after treatment began; participants subsequently were retested 1 year later to assess cognitive change.Daily high-dose B vitamin capsule (40 mg of folic acid, 100 mg of vitamin B(6), and 2 mg of vitamin B(12)) or placebo.Cognitive function at initial assessment and 1 year later.Telephone Interview of Cognitive Status-modified, supplemented with attention, working memory, and executive function tests.Initial cognitive function was impaired in approximately 19% of patients regardless of treatment assignment (vitamin or placebo) or kidney disease status (advanced CKD or ESRD). Treatment decreased tHcy levels by 26.7%. Unadjusted and adjusted analyses showed that treatment did not improve initial cognitive outcomes or affect subsequent cognitive status 1 year later.Cognitive assessments began after treatment was initiated; cognitive assessment was limited.Treatment with high daily doses of B vitamins, which decreased tHcy levels, did not affect cognitive outcomes in patients with advanced CKD and ESRD.
Project description:BackgroundProprotein convertase subtilisin/kexin 9 (PCSK9) has been proposed as a novel target for coronary artery disease (CAD). Familial hypercholesterolemia (FH) is characterized by high prevalence of CAD and major cardiovascular events (MACEs). However, no data is available on the association between PCSK9 levels and MACEs in FH patients with standard lipid lowering therapy.MethodsA total of 338 consecutive heterozygous FH (Dutch Lipid Clinic Network score ≥ 6) was enrolled and followed up for the occurrence of MACEs. Multidetector CT and coronary angiography were performed to determine coronary artery calcification score (CACS) and Gensini score (GS). Multivariable Cox regression analyses were used to calculate hazard ratios (HRs) with 95% confidence intervals (CIs). Plasma PCSK9 concentrations were determined by enzyme immunoassay.ResultsPCSK9 was independently and positively associated CACS and GS at baseline. During a mean follow-up of 3 years, 33 (9.8%) events occurred. Patients with MACEs had higher median PCSK9 compared with those without (332.47 vs. 311.89 ng/mL, p = 0.038). Kaplan-Meier analysis revealed that patients with higher PCSK9 presented lower event-free survival (p = 0.0017). PCSK9 was statistically correlated with MACEs after adjusting for confounding factors, with the HR per SD being 1.86 (1.31-2.65) and 3.70 (1.16-11.82) for the highest tertile compared with the lowest tertile. Adding PCSK9 to Cox prediction model led to a statistical improvement in net reclassification and integrated discrimination.ConclusionElevated levels of PCSK9 were positively associated with the development of CAD and future cardiovascular events, suggesting that measurement of PCSK9 concentration might be useful for cardiovascular risk stratification. Further studies are needed to confirm our results.
Project description:BackgroundThe comparative safety and effectiveness of treatments to prevent thromboembolic complications in atrial fibrillation (AF) remain uncertain.PurposeTo compare the effectiveness of medical and procedural therapies in preventing thromboembolic events and bleeding complications in adults with nonvalvular AF.Data sourcesEnglish-language studies in several databases from 1 January 2000 to 14 February 2018.Study selectionTwo reviewers independently screened citations to identify comparative studies of treatments to prevent stroke in adults with nonvalvular AF who reported thromboembolic or bleeding complications.Data extractionTwo reviewers independently abstracted data, assessed study quality and applicability, and rated strength of evidence.Data synthesisData from 220 articles were included. Dabigatran and apixaban were superior and rivaroxaban and edoxaban were similar to warfarin in preventing stroke or systemic embolism. Apixaban and edoxaban were superior and rivaroxaban and dabigatran were similar to warfarin in reducing the risk for major bleeding. Treatment effects with dabigatran were similar in patients with renal dysfunction (interaction P > 0.05), and patients younger than 75 years had lower bleeding rates with dabigatran (interaction P < 0.001). The benefit of treatment with apixaban was consistent in many subgroups, including those with renal impairment, diabetes, and prior stroke (interaction P > 0.05 for all). The greatest bleeding risk reduction was observed in patients with a glomerular filtration rate less than 50 mL/min/1.73 m2 (P = 0.003). Similar treatment effects were observed for rivaroxaban and edoxaban in patients with prior stroke, diabetes, or heart failure (interaction P > 0.05 for all).LimitationHeterogeneous study populations, interventions, and outcomes.ConclusionThe available direct-acting oral anticoagulants (DOACs) are at least as effective and safe as warfarin for patients with nonvalvular AF. The DOACs had similar benefits across several patient subgroups and seemed safe and efficacious for a wide range of patients with nonvalvular AF.Primary funding sourcePatient-Centered Outcomes Research Institute. (PROSPERO: CRD42017069999).
Project description:BackgroundHypertension is one of the most common medical problems during pregnancy. Hypertensive disorders of pregnancy (HDP) increase the risk of premature cardiovascular disease (CVD) 2- to 4-fold within 10 years after delivery. Early health behaviour modifications may prevent or manage several cardiovascular risk factors. Importantly, compared with women without HDP, fewer women with HDP achieve national dietary guidelines to prevent CVD. This highlights an opportunity for programs tailored for women post-HDP to support their nutritional behaviours as a key component of postpartum CVD preventive care. This systematic review investigated the impacts of nutrition modifications on lowering measures of CVD risk after HDP.MethodsFour electronic databases (MEDLINE, EMBASE, CINAHL, Cochrane Library) were searched in October 2022 with a search strategy focused on nutrition programs/interventions and women post-HDP. Additional inclusion criteria were original research and reported outcome of CVD risk or cardiovascular risk factors.ResultsSix studies were included: 4 experimental trials and 2 prospective cohort studies. Of the nutrition interventions, 4 were embedded within comprehensive health behaviour intervention programs. Outcome measures varied, but all studies reported blood pressure. A narrative synthesis found that the range of changes in blood pressure varied from no change to clinically meaningful change.ConclusionsThis review found statistically nonsignificant yet clinically important improvements in measures of cardiovascular risk across a range of nutritional interventions in women after HDP. Further high-quality evidence is needed to inform the design and implementation of nutritional preventive cardiovascular care targeting this high CVD-risk population.
Project description:BackgroundWhile folic acid (FA) is widely used to treat elevated total homocysteine (tHcy), promoting vascular health by reducing vascular oxidative stress and modulating endothelial nitric oxide synthase, the optimal daily dose and individual variation by MTHFR C677T genotypes have not been well studied. Therefore, this study aimed to explore the efficacy of eight different FA dosages on tHcy lowering in the overall sample and by MTHFR C677T genotypes.MethodsThis multicentered, randomized, double-blind, controlled clinical trial included 2697 eligible hypertensive adults with elevated tHcy (≥ 10 mmol/L) and without history of stroke and cardiovascular disease. Participants were randomized into eight dose groups of FA combined with 10 mg enalapril maleate, taken daily for 8 weeks of treatment.ResultsThe intent to treat analysis included 2163 participants. In the overall sample, increasing FA dosage led to steady tHcy reduction within the FA dosing range of 0-1.2 mg. However, a plateau in tHcy lowering was observed in FA dose range of 1.2-1.6 mg, indicating a ceiling effect. In contrast, FA doses were positively and linearly associated with serum folate levels without signs of plateau. Among MTHFR genotype subgroups, participants with the TT genotype showed greater efficacy of FA in tHcy lowering.ConclusionsThis randomized trial lent further support to the efficacy of FA in lowering tHcy; more importantly, it provided critically needed evidence to inform optimal FA dosage. We found that the efficacy of FA in lowering tHcy reaches a plateau if the daily dosage exceeds 1.2 mg, and only has a small gain by increasing the dosage from 0.8 to 1.2 mg.ClinicaltrialsGov identifierNCT03472508 (Registration Date: March 21, 2018).
Project description:AimsLipoprotein(a) concentration is associated with first cardiovascular events in clinical trials. It is unknown if this relationship holds for total (first and subsequent) events. In the ODYSSEY OUTCOMES trial in patients with recent acute coronary syndrome (ACS), the proprotein convertase subtilisin/kexin type 9 inhibitor alirocumab reduced lipoprotein(a), low-density lipoprotein cholesterol (LDL-C), and cardiovascular events compared with placebo. This post hoc analysis determined whether baseline levels and alirocumab-induced changes in lipoprotein(a) and LDL-C [corrected for lipoprotein(a) cholesterol] independently predicted total cardiovascular events.Methods and resultsCardiovascular events included cardiovascular death, non-fatal myocardial infarction, stroke, hospitalization for unstable angina or heart failure, ischaemia-driven coronary revascularization, peripheral artery disease events, and venous thromboembolism. Proportional hazards models estimated relationships between baseline lipoprotein(a) and total cardiovascular events in the placebo group, effects of alirocumab treatment on total cardiovascular events by baseline lipoprotein(a), and relationships between lipoprotein(a) reduction with alirocumab and subsequent risk of total cardiovascular events. Baseline lipoprotein(a) predicted total cardiovascular events with placebo, while higher baseline lipoprotein(a) levels were associated with greater reduction in total cardiovascular events with alirocumab (hazard ratio Ptrend = 0.045). Alirocumab-induced reductions in lipoprotein(a) (median -5.0 [-13.6, 0] mg/dL) and corrected LDL-C (median -51.3 [-67.1, -34.0] mg/dL) independently predicted lower risk of total cardiovascular events. Each 5-mg/dL reduction in lipoprotein(a) predicted a 2.5% relative reduction in cardiovascular events.ConclusionBaseline lipoprotein(a) predicted the risk of total cardiovascular events and risk reduction by alirocumab. Lipoprotein(a) lowering contributed independently to cardiovascular event reduction, supporting the concept of lipoprotein(a) as a treatment target after ACS.
Project description:The purpose is to investigate the added prognostic value of coronary artery calcium (CAC), thoracic aortic calcium (TAC), and heart valve calcium scores for prediction of a combined endpoint of recurrent major cardiovascular events and cardiovascular interventions (MACE +) in patients with established cardiovascular disease (CVD). In total, 567 patients with established CVD enrolled in a substudy of the UCC-SMART cohort, entailing cardiovascular CT imaging and calcium scoring, were studied. Five Cox proportional hazards models for prediction of 4-year risk of MACE + were developed; traditional CVD risk predictors only (model I), with addition of CAC (model II), TAC (model III), heart valve calcium (model IV), and all calcium scores (model V). Bootstrapping was performed to account for optimism. During a median follow-up of 3.43 years (IQR 2.28-4.74) 77 events occurred (MACE+). Calibration of predicted versus observed 4-year risk for model I without calcium scores was good, and the c-statistic was 0.65 (95%CI 0.59-0.72). Calibration for models II-V was similar to model I, and c-statistics were 0.67, 0.65, 0.65, and 0.68 for model II, III, IV, and V, respectively. NRIs showed improvement in risk classification by model II (NRI 15.24% (95%CI 0.59-29.39)) and model V (NRI 20.00% (95%CI 5.59-34.92)), but no improvement for models III and IV. In patients with established CVD, addition of the CAC score improved performance of a risk prediction model with classical risk factors for the prediction of the combined endpoint MACE+ . Addition of the TAC or heart valve score did not improve risk predictions.