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Chen J, Rees A, Coughlan CH, Goodison W, Murphy E, Chandratheva A. Ischaemic stroke with multi-focal venous and arterial thrombosis due to hyperhomocysteinemia: anabolic androgenic steroid use and MTHFR c.667 C > T variant - a case report. BMC Neurol 2023; 23:167. [PMID: 37101129 PMCID: PMC10131300 DOI: 10.1186/s12883-023-03197-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Accepted: 04/03/2023] [Indexed: 04/28/2023] Open
Abstract
BACKGROUND Severely elevated serum homocysteine is a rare cause of ischaemic stroke and extra-cranial arterial and venous thrombosis. Several factors can lead to mild elevation of homocysteine including dietary folate and B12 deficiency, and genetic variants of the methylenetetrahydrofolate reductase (MTHFR) enzyme. The use of Anabolic androgenic steroid (AAS) is under-reported, but increasingly linked to ischaemic stroke and can raise homocysteine levels. CASE REPORT We present a case of a man in his 40s with a large left middle cerebral artery (MCA) territory ischaemic stroke and combined multifocal, extracranial venous, and arterial thrombosis. His past medical history was significant for Crohn's disease and covert use of AAS. A young stroke screen was negative except for a severely elevated total homocysteine concentration, folate and B12 deficiencies. Further tests revealed he was homozygous for the methylenetetrahydrofolate reductase enzyme thermolabile variant (MTHFR c.667 C > T). The etiology of this stroke was a hypercoagulable state induced by raised plasma homocysteine. Raised homocysteine in this case was likely multifactorial and related to chronic AAS use in combination with the homozygous MTHFR c.677 C > T thermolabile variant, folate deficiency and, vitamin B12 deficiency. CONCLUSION In summary, hyperhomocysteinemia is an important potential cause of ischaemic stroke and may result from genetic, dietary, and social factors. Anabolic androgenic steroid use is an important risk factor for clinicians to consider, particularly in cases of young stroke with elevated serum homocysteine. Testing for MFTHR variants in stroke patients with raised homocysteine may be useful to guide secondary stroke prevention through adequate vitamin supplementation. Further studies looking into primary and secondary stroke prevention in the high-risk MTHFR variant cohort are necessary.
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Affiliation(s)
- Jpk Chen
- National Hospital for Neurology and Neurosurgery, London, UK.
| | - A Rees
- National Hospital for Neurology and Neurosurgery, London, UK
| | - C H Coughlan
- University College London Hospitals NHS Foundation Trust, London, UK
| | - W Goodison
- National Hospital for Neurology and Neurosurgery, London, UK
| | - E Murphy
- University College London Hospitals NHS Foundation Trust, London, UK
| | - A Chandratheva
- University College London Hospitals NHS Foundation Trust, London, UK
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Holmen M, Hvas AM, Arendt JFH. Hyperhomocysteinemia and Ischemic Stroke: A Potential Dose-Response Association-A Systematic Review and Meta-analysis. TH OPEN 2021; 5:e420-e437. [PMID: 34595387 PMCID: PMC8463136 DOI: 10.1055/s-0041-1735978] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 07/19/2021] [Indexed: 12/17/2022] Open
Abstract
Background and Purpose Previous studies suggest an association between increased homocysteine (Hcy) and risk of ischemic stroke. Yet, it remains unknown whether a dose-response association exists between Hcy levels and risk of ischemic stroke. Methods Systematic literature searches were performed in PubMed, Embase, Scopus, and Web of Science. Inclusion criteria were studies investigating ischemic stroke risk in an adult population with measured Hcy levels. We computed odds ratios (ORs) for a 5 µmol/L increase in Hcy levels using a random effects meta-analysis. Results In total, 108 studies met the inclusion criteria of which 22 were rated as high-quality studies, and 20 studies included a dose-response analysis. Hcy levels were analyzed either as a continuous or categorical variable. The majority of the studies found an increased risk of ischemic stroke when comparing the highest-to-lowest Hcy strata. A graded association was observed over the Hcy strata, indicating a dose-response association, with the most apparent effect when Hcy levels exceeded approximately 15 µmol/L. No studies explored a potential nonlinear association between Hcy levels and ischemic stroke. Six studies were included in a meta-analysis, showing an OR of 1.43 (95% confidence interval [CI]: 1.28-1.61) per 5 µmol/L increase in Hcy levels. Conclusion This review and meta-analysis indicate a dose-response association between Hcy levels and ischemic stroke. An evident increase in effect measures was observed when Hcy levels exceeded 15 µmol/L, indicating a nonlinear association between ischemic stroke and Hcy levels. This nonlinear association warrants further study. This study is registered with clinical trial ( https://www.crd.york.ac.uk/prospero/ ; unique identifier: CRD42019130371).
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Affiliation(s)
- Marte Holmen
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
| | - Anne-Mette Hvas
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
- Department of Clinical Medicine, Aarhus University, Aarhus, Denmark
| | - Johan F. H. Arendt
- Department of Clinical Biochemistry, Aarhus University Hospital, Aarhus, Denmark
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Kell DB, Pretorius E. The simultaneous occurrence of both hypercoagulability and hypofibrinolysis in blood and serum during systemic inflammation, and the roles of iron and fibrin(ogen). Integr Biol (Camb) 2015; 7:24-52. [PMID: 25335120 DOI: 10.1039/c4ib00173g] [Citation(s) in RCA: 61] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Although the two phenomena are usually studied separately, we summarise a considerable body of literature to the effect that a great many diseases involve (or are accompanied by) both an increased tendency for blood to clot (hypercoagulability) and the resistance of the clots so formed (hypofibrinolysis) to the typical, 'healthy' or physiological lysis. We concentrate here on the terminal stages of fibrin formation from fibrinogen, as catalysed by thrombin. Hypercoagulability goes hand in hand with inflammation, and is strongly influenced by the fibrinogen concentration (and vice versa); this can be mediated via interleukin-6. Poorly liganded iron is a significant feature of inflammatory diseases, and hypofibrinolysis may change as a result of changes in the structure and morphology of the clot, which may be mimicked in vitro, and may be caused in vivo, by the presence of unliganded iron interacting with fibrin(ogen) during clot formation. Many of these phenomena are probably caused by electrostatic changes in the iron-fibrinogen system, though hydroxyl radical (OH˙) formation can also contribute under both acute and (more especially) chronic conditions. Many substances are known to affect the nature of fibrin polymerised from fibrinogen, such that this might be seen as a kind of bellwether for human or plasma health. Overall, our analysis demonstrates the commonalities underpinning a variety of pathologies as seen in both hypercoagulability and hypofibrinolysis, and offers opportunities for both diagnostics and therapies.
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Affiliation(s)
- Douglas B Kell
- School of Chemistry and The Manchester Institute of Biotechnology, The University of Manchester, 131, Princess St, Manchester M1 7DN, Lancs, UK.
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4
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Diet and haemostasis — A comprehensive overview. Blood Rev 2015; 29:231-41. [DOI: 10.1016/j.blre.2014.12.005] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2014] [Accepted: 12/08/2014] [Indexed: 12/15/2022]
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Tu WJ, Zhao SJ, Liu TG, Yang DG, Chen H. Combination of high-sensitivity C-reactive protein and homocysteine predicts the short-term outcomes of Chinese patients with acute ischemic stroke. Neurol Res 2013; 35:912-921. [PMID: 23816540 DOI: 10.1179/1743132813y.0000000228] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/11/2023]
Abstract
BACKGROUND Ischemic stroke is one of the most common causes of death worldwide. Early and accurate prediction of outcome in acute ischemic stroke (AIS) is important and influences risk-optimized therapeutic strategies. We investigated the changes in high-sensitivity C-reactive protein (Hs-CRP) and homocysteine (HCY) levels, two of the risk factors, during the acute period of AIS and evaluated the relationship between these levels and short-term prognosis. METHODS We prospectively studied 189 patients with AIS who were admitted within 24 hours after the onset of symptoms. Serum Hs-CRP, HCY levels, and National Institutes of Health Stroke Scale (NIHSS) were measured at the time of admission. Short-term functional outcome was measured by the modified Rankin scale (mRS), 90 days after admission. RESULTS The median serum Hs-CRP and HCY levels were significantly higher in AIS patients as compared to normal controls (P < 0.0001, respectively). High-sensitivity C-reactive protein and HCY were independent prognostic markers of functional outcome and death (adjusted for age and the NIHSS) in patients with AIS. In receiver operating characteristic curve analysis, the prognostic accuracy of the combined model (HCY and Hs-CRP) was higher compared to all measured biomarkers individually and the NIHSS score. CONCLUSION High-sensitivity C-reactive protein and HCY are independent predictors of short-term outcome and mortality after AIS. The combined model may provide additional general prognostic information.
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Affiliation(s)
- Wen-Jun Tu
- China Rehabilitation Research Center, Beijing, P. R. China
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8
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Wu XQ, Ding J, Ge AY, Liu FF, Wang X, Fan W. Acute phase homocysteine related to severity and outcome of atherothrombotic stroke. Eur J Intern Med 2013; 24:362-7. [PMID: 23391475 DOI: 10.1016/j.ejim.2013.01.015] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2012] [Revised: 01/08/2013] [Accepted: 01/14/2013] [Indexed: 11/28/2022]
Abstract
BACKGROUND Homocysteine (HCY) is associated with risk of stroke, but whether HCY affects stroke severity and prognosis remains controversial. We hypothesized HCY has an impact on atherothrombosis and this prospective study was aimed to explore the association between acute phase HCY with stroke severity and outcome in patients with atherothrombosis. METHODS Patients <72 h after symptom onset were categorized by the modified Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification and those typed as atherothrombosis were included. Neurologic function was assessed with National Institute of Health Stroke Score (NIHSS) <72 h after symptom onset and Modified Rankin Scale (mRS) and Barthel Index (BI) 6-month, 12-month and 18-month poststroke respectively. HCY was recorded <72 h after symptom onset. Participants were divided into hHCY (HCY>15 μmol/l) and nhHCY (HCY≤15 μmol/l). The correlation between HCY and mRS was analyzed. RESULTS 125 of 130 participants without HCY interventional therapy completed the 18-month follow-up. There was no difference in demographics, histories of hypertension, diabetes mellitus, coronary heart disease, previous cerebral vascular event, and plasma low-density lipoprotein between hHCY and nhHCY. NIHSS, mRS were significantly higher and BI was significantly lower in hHCY than in nhHCY. The 18-month recurrence rate in hHCY (21.0%) was significantly higher than that in nhHCY (6.8%). Spearman correlation analysis revealed correlation between HCY and mRS (p=0.000). By ordinal logistic regression, HCY was an independent predictor of 18-month mRS (odds ratio 1.08, 95% confidence interval 1.04-1.13, p=0.000). CONCLUSIONS Acute phase elevated HCY correlated with severity and prognosis in patients with atherothrombotic stroke.
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Affiliation(s)
- Xu-Qing Wu
- Department of Neurology, Zhongshan Hospital, Fudan University, 200032, Shanghai, China
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Abstract
Abstract
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Prospective study of first stroke in relation to plasma homocysteine and MTHFR 677C>T and 1298A>C genotypes and haplotypes – evidence for an association with hemorrhagic stroke. Clin Chem Lab Med 2011; 49:1555-62. [DOI: 10.1515/cclm.2011.234] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Stankovic S, Majkic-Singh N. Genetic aspects of ischemic stroke: coagulation, homocysteine, and lipoprotein metabolism as potential risk factors. Crit Rev Clin Lab Sci 2010; 47:72-123. [DOI: 10.3109/10408361003791520] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Bougteba A, Basir A, Kissani N. [Recurrent ischemic stroke revealing Biermer's disease]. Rev Neurol (Paris) 2010; 165:1099-102. [PMID: 19446857 DOI: 10.1016/j.neurol.2009.01.051] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2008] [Revised: 11/04/2008] [Accepted: 01/25/2009] [Indexed: 11/29/2022]
Abstract
INTRODUCTION Biermer's disease is an autoimmune disorder characterized by vitamin B12 deficiency. Ischemic stroke is an uncommon complication of Biermer's disease, possibly though hyperhomocysteinemia. CASE REPORT A 58-year-old male presented with recurrent ischemic stroke. Extensive investigations were normal, except for a high plasma level of homocysteine in the context of pernicious anemia which was otherwise asymptomatic. DISCUSSION Hyperhomocysteinemia is a known marker, and probably a risk factor, for stroke, fostering atherosclerosis and thrombosis. It can be found among individuals suffering from homocysteinuria, but also when there is deficiency of vitamin B12 or folic acid. Vitamin B12 supplementation would reduce homocysteine concentration which in turn would reduce the risk of ischemic stroke.
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Affiliation(s)
- A Bougteba
- Service de neurologie, hôpital civil, Tétouan, Maroc.
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C677T polymorphism of the methylenetetrahydrofolate reductase gene and the risk of ischemic stroke in Polish subjects. J Appl Genet 2009; 50:63-7. [DOI: 10.1007/bf03195654] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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Kalita J, Kumar G, Bansal V, Misra UK. Relationship of homocysteine with other risk factors and outcome of ischemic stroke. Clin Neurol Neurosurg 2009; 111:364-7. [PMID: 19185985 DOI: 10.1016/j.clineuro.2008.12.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 11/14/2008] [Accepted: 12/24/2008] [Indexed: 11/19/2022]
Abstract
OBJECTIVE Hyperhomocysteinemia (HH) is an emerging risk factor for ischemic stroke but its role in outcome is controversial. We compare the risk factors, nature of stroke and outcome of patients with and without hyperhomocysteinemia. PATIENTS AND METHODS CT proven ischemic stroke patients were included. The conventional risk factors such as diabetes, hypertension, hyperlipidemia, obesity, smoking, and family history of stroke were recorded. Dietary history was noted. Fasting serum homocysteine (Hcy), B12 and folic acid were estimated after 1 month of stroke. Severity of stroke was assessed by Canadian Neurological Scale (CNS) and outcome at 3 months by Barthel Index (BI) score into good (BI > or = 12) and poor (BI < 12). Serum Hcy, B12 and folic acid were also estimated in 200 normal healthy volunteers. RESULTS There were 198 patients with ischemic stroke whose median age was 56 years and 36 were females. In the study group, 41.4% patients were vegetarian, 55.1% hypertensive, 24.7% diabetic, 30.8% smoker, 61.1% sedentary and 28.8% obese. 23.2% had past history of stroke and 21.7% had stroke in their first degree relative. Serum cholesterol was elevated in 11.7% and LDL in 10.8% patients. Serum Hcy was elevated in 60.6% and serum B12 low in 25.7% and folic acid in 42.1%. Hcy levels correlated with serum B12 and LDL. Patients with hyperhomocysteinemia had significantly better outcome at 3 months. Hcy levels in stroke patients did not significantly differ from controls. CONCLUSION Hyperhomocysteinemia is found in 60.6% stroke patients, which is related to low serum B12 level. Patients with hyperhomocysteinemia had a better 3-month outcome.
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Affiliation(s)
- Jayantee Kalita
- Department of Neurology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Raebareily Road, Lucknow 226014, India
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15
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Colucci M, Cattaneo M, Martinelli I, Semeraro F, Binetti BM, Semeraro N. Mild hyperhomocysteinemia is associated with increased TAFI levels and reduced plasma fibrinolytic potential. J Thromb Haemost 2008; 6:1571-7. [PMID: 18624976 DOI: 10.1111/j.1538-7836.2008.03070.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
BACKGROUND Mild hyperhomocysteinemia (HHcy) has been shown to be associated with impaired fibrinolysis, but some aspects of this association are unclear. OBJECTIVE Using an in vitro model of physiological relevance, we investigated whether and how HHcy influences plasma fibrinolytic potential. PATIENTS/METHODS We studied 176 patients with previous venous thromboembolism, 58 with HHcy, 118 with normal total homocysteine (tHcy) levels (NHcy), at least 3 months after withdrawal of anticoagulant therapy. Plasma fibrinolytic potential was measured as the fibrinolysis time of tissue factor (TF)-induced clots exposed to 15 ng mL(-1) t-PA. RESULTS Fibrinolysis time was longer in HHcy than in NHcy patients, but this difference disappeared when the assay was performed in the presence of the TAFIa inhibitor, PTCI. Plasma levels of thrombin activatable fibrinolysis inhibitor (TAFI) and factor VIII (FVIII) were higher in HHcy than NHcy, whereas PAI-1, fibrinogen and endogenous thrombin potential were similar. Using multivariate analysis, plasma tHcy was identified as an independent predictor of fibrinolysis time. Experiments in which native fibrinogen was replaced by purified fibrinogen suggested that alterations of fibrinogen structure did not contribute appreciably to the hypofibrinolysis of HHcy plasma samples. The acute increase of tHcy either in vivo (after an oral methionine load) or in vitro (after incubation of normal plasma with 0.5 mm DL-Hcy) had no effects on fibrinolysis or TAFI levels. CONCLUSIONS We describe an enhanced TAFI-related antifibrinolytic activity in mild HHcy, which might account for the reported heightened thrombosis risk; however, it is unknown whether HHcy is causally related to hypofibrinolysis or an associated bystander.
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Affiliation(s)
- M Colucci
- Department of Biomedical Sciences and Human Oncology, Section of General and Experimental Pathology, University of Bari, Bari, Italy.
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Holmes VA. Changes in haemostasis during normal pregnancy: does homocysteine play a role in maintaining homeostasis? Proc Nutr Soc 2007; 62:479-93. [PMID: 14506896 DOI: 10.1079/pns2003251] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Homocysteine, derived from the demethylation of the ammo acid methionine, is either further catabolised by trans-sulfuration to cysteine or remethylated to methionine. Remethylation to methionine requires the cofactors, folate and vitamin B12. Folate is an effective homocysteine-lowering agent and, thus, homocysteine and folate status are inversely related. Hyperhomocysteinaemia is a strong independent risk factor for venous thromboembolism (VTE) and is associated with adverse pregnancy outcomes such as pre-eclampsia, placental abruption, early pregnancy loss and neural-tube defects. Pregnancy is a risk factor for VTE as a result of prothrombotic changes in levels of haemostatic factors. However, despite this hypercoagulable state, the incidence of pregnancy-associated VTE is relatively low. Hyperhomocysteinaemia is associated with abnormalities in markers of coagulation activation, and recent research suggests that folic acid supplementation, as well as lowering homocysteine, lowers markers of coagulation activation and increases levels of coagulation inhibitors. Tissue factor (TF) is the initiator of blood coagulationin vivo, and homocysteine induces TF expressionin vitro. During pregnancy, monocyte TF expression is lower than that in the non-pregnant state, and this lowering of TF may act to counterbalance increases in coagulation activation. Furthermore, despite a high folate requirement, several studies have reported that homocysteine is lower in normal pregnancy than in the non-pregnant state. Although the exact mechanism of homocysteine lowering during pregnancy is unclear, one possible outcome of lower homocysteine may be the protection of women from pregnancy complications and VTE, and thus lower homocysteine may contribute to maintaining homeostasis in haemostasis.
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Affiliation(s)
- Valerie A Holmes
- Northern Ireland Centre for Diet and Health (NICHE), University of Ulster, Coleraine BT52 1SA, UK.
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Haapaniemi E, Helenius J, Soinne L, Syrjälä M, Kaste M, Tatlisumak T. Serial measurements of plasma homocysteine levels in early and late phases of ischemic stroke. Eur J Neurol 2007; 14:12-7. [PMID: 17222107 DOI: 10.1111/j.1468-1331.2006.01518.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
High plasma levels of homocysteine (Hcy) may predispose to ischemic stroke (IS), but results of previous studies have been conflicting. We decided to determine in IS patients whether their Hcy levels are elevated, whether levels vary at different time points following stroke, whether levels are associated with stroke severity, outcome, recurrence, etiology, infarct volume, or risk factors, and whether levels are correlated with hemostatic factors or C-reactive protein values. We measured plasma Hcy levels in 102 consecutive IS patients on admission and at 1 week, 1 month, and 3 months after stroke and once in 102 control subjects. Hemostatic factors were measured in 55 patients. Compared with controls, plasma Hcy levels in patients were significantly lower on admission but not at later time points, with levels increasing by week and remaining at this level for 3 months. Hcy levels showed a positive correlation with age and a negative correlation with Mini-Mental State Examination (MMSE) scores. Plasma Hcy levels inversely correlated with plasminogen activator inhibitor type-1. Decreased Hcy levels on admission may reflect the strength of the acute-phase response rather than a pathogenetic event. The negative correlation between Hcy levels and MMSE scores is more probably age-related than stroke-related.
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Affiliation(s)
- E Haapaniemi
- Department of Neurology, Helsinki University Central Hospital, Helsinki, Finland.
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Leemann B, Boughanem N, Schnider A. L’accident ischémique cérébral, une complication rare de la maladie de Biermer. Rev Neurol (Paris) 2006; 162:1007-10. [PMID: 17028570 DOI: 10.1016/s0035-3787(06)75112-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
INTRODUCTION Stroke in a young adult justifies an extensive etiologic workup. OBSERVATION We present a 44-year-old women victim of a frontal ischemic stroke. Extensive evaluation was normal, except for high plasma level of homocysteine in the context of pernicious anemia, otherwise asymptomatic. DISCUSSION Hyperhomocysteinemia is a known marker, and probably risk factor for stroke, fostering atherosclerosis and thrombosis. It can be found among individuals suffering from homocystinuria, in individuals homozygous for the MHTFR T allele but also when there is deficiency of vitamin B12 or folic acid. Although it is very seldom ascribed, pernicious anemia would be a cause of stroke, possibly though hyperhomocysteinemia.
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Affiliation(s)
- B Leemann
- Service de Rééducation, HUG, Switzerland.
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19
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Affiliation(s)
- Madeline C Fields
- Department of Neurology, Stroke Center, The Mount Sinai School of Medicine, New York 10029-6574, USA
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20
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Bushnell CD, Goldstein LB. Neurologists’ Evaluation and Treatment of Hyperhomocysteinemia in Stroke Patients. J Stroke Cerebrovasc Dis 2005; 14:101-6. [PMID: 17904008 DOI: 10.1016/j.jstrokecerebrovasdis.2005.01.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2004] [Accepted: 12/22/2004] [Indexed: 11/30/2022] Open
Abstract
Observational study data have suggested that neurologists preferentially selected younger patients with generally few traditional stroke risk factors for homocysteine testing. The aim of this study was to corroborate observational data by assessing neurologists' reported practices for the detection and treatment of hyperhomocysteinemia in patients with acute ischemic stroke. All academic neurology faculty (n = 49), trainees (neurology residents/fellows, n = 53), and a random sample of community-based neurologists (n = 66) throughout North Carolina were surveyed regarding their homocysteine testing and treatment practices. Nine neurologists were ineligible because they had either retired or moved out of state. A total of 93 of the remaining 159 surveys (58.5%) were completed (response rates: faculty, 74%; trainees, 47%; community-based neurologists, 56%). Patients age < 50 years (n = 52; 63%) and the absence of traditional stroke risk factors (n = 57; 70%) were the most common factors cited as prompting homocysteine testing. The homocysteine level threshold for treatment varied independently by practice type (faculty: median, 14 mumol/L; range, 6-16 mumol/L; trainees: median, 14.5 mumol/L; range, 10-20 mumol/L; community-based: median, 10.4 mumol/L; range, 7-15 mumol/L; P = .01), the number of stroke patients evaluated during a typical week (Spearman's r = .32; P = .034), and year of training completion (Spearman's r = .41; P = .003). About half (51%) treat elevated homocysteine with a combination of folate, vitamin B(12), and vitamin B(6). Consistent with observational data, the majority of the neurologists surveyed report that they select young stroke patients who lack traditional stroke risk factors for homocysteine testing. Thresholds for treatment varied between community-based and academic neurologists and correlated with the physicians' stroke patient volume.
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Affiliation(s)
- Cheryl D Bushnell
- Department of Medicine (Neurology), Duke University Medical Center, Durham, North Carolina, USA
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Abstract
Patients with ischemic stroke are sometimes found to have an underlying inherited (deficiency of protein C, protein S, antithrombin III, activated protein C resistance, prothrombin gene mutation, hyperhomocysteinemia) or acquired thrombophilia (lupus anticoagulant and anticardiolipin antibodies, hyperhomocysteinemia). Patient selection for thrombophilia screening is, therefore, a frequent question in managing patients with ischemic stroke. In this review we discuss patient selection and timing for laboratory tests for thrombophilia screening in stroke patients based on a literature review and we calculated overall costs per year in Germany for testing patients older than 18 years with an ischemic stroke of undetermined cause. As there is a lack of studies comparing anticoagulation with antiplatelet therapy in patients with diagnosed thrombophilia, laboratory screening for thrombophilia even in a selected group of patients with cryptogenic ischemic stroke remains of questionable value at present. An exception appears to be testing for lupus anticoagulant and anticardiolipin antibodies in younger patients with suspected antiphospholipid syndrome (two positive test results necessary), because anticoagulation seems to be superior to aspirin in patients with antiphospholipid syndrome.
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Affiliation(s)
- R Weber
- Klinik für Neurologie, Universitätsklinikum Essen, 45122 Essen
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Splaver A, Lamas GA, Hennekens CH. Homocysteine and cardiovascular disease: biological mechanisms, observational epidemiology, and the need for randomized trials. Am Heart J 2004; 148:34-40. [PMID: 15215789 DOI: 10.1016/j.ahj.2004.02.004] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Basic research indicates that homocysteine causes endothelial dysfunction and damage, accelerates thrombin formation, inhibits native thrombolysis, promotes lipid peroxidation through free radical formation, and induces vascular smooth muscle proliferation and monocyte chemotaxis. Most, but not all, observational epidemiological studies indicate that individuals with higher homocysteine levels have increased risks of cardiovascular disease. The magnitude ranges from approximately 20% in prospective studies to approximately 80% in retrospective case-control studies. In all observational epidemiological studies, however, the amount of uncontrolled and uncontrollable confounding is as large as the postulated small to moderate effect size. Thus, the totality of evidence should include randomized trials of sufficient sample size and duration with clinical end points. Folic acid reduces levels of homocysteine, but at present, despite several plausible biological mechanisms and a large body of observational epidemiological data, it is unclear whether supplementation will reduce risks of cardiovascular disease. It is also unclear whether any benefit of folic acid is attributable to lowering homocysteine levels. The current evidence is necessary, but not sufficient to judge causality. Such judgments await the availability of data from large-scale randomized trials. The availability of such data would permit rational clinical decision-making for individual patients and policy decisions for the health of the general public.
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Affiliation(s)
- Adam Splaver
- Division of Cardiology Research, Mount Sinai Medical Center, University of Miami School of Medicine Miami Beach, Fla USA
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Beccia M, Mele MC, Ferrari M, Ranieri M, Barini A, Rasura M. Young stroke and basal plasma and post-methionine load homocysteine and cysteine levels 1 year after the acute event: do plasma folates make the difference? Eur J Neurol 2004; 11:269-75. [PMID: 15061829 DOI: 10.1046/j.1468-1331.2003.00774.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We conducted a case-control study to evaluate the relationship between ischemic stroke in young adults (<45 years of age) and plasma homocysteine (Hcy), plasma folate and vitamin B(12), after a methionine load. We studied 42 patients with a history of ischemic stroke and 29 controls with a negative clinical history of cardio- or cerebrovascular diseases, venous thrombosis and renal disease. A fasting blood sample was drawn from each participant; the second and third samples were collected, respectively, 120 and 240 min after the methionine load. Whilst there was no difference between controls and patients in basal total homocysteine (tHcy), we found a statistically significant difference in both the 120- and 240-min samples. We compared the basal and 240-min tHcy in patients and controls. We obtained a median value of 17.8 and 11.6 micromol/l in patients and controls, respectively. The difference between these two values was highly significant. The methionine loading test (MLT) reveals Hcy metabolism abnormalities that were not revealed by the basal sample. MLT may help identify and treat this new risk factor, which seems to be both atherogenic and prothrombotic, and is hypothesized to operate through various mechanisms.
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Affiliation(s)
- M Beccia
- Department of Neurological Sciences, II Faculty of Medicine, University of Rome 'La Sapienza', Rome, Italy.
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Kim RJ, Becker RC. Association between factor V Leiden, prothrombin G20210A, and methylenetetrahydrofolate reductase C677T mutations and events of the arterial circulatory system: a meta-analysis of published studies. Am Heart J 2003; 146:948-57. [PMID: 14660985 DOI: 10.1016/s0002-8703(03)00519-2] [Citation(s) in RCA: 183] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
BACKGROUND The association between the inherited gene mutations of factor V, prothrombin, and homocysteine metabolism and venous thromboembolic events is accepted widely; however, their influence on the arterial circulatory system remains controversial. METHODS We performed a MEDLINE search to identify published case-control and cohort studies correlating the factor V Leiden, prothrombin (PT) G20210A, and methylenetetrahydrofolate reductase (MTHFR) C677T (TT genotype) mutations with myocardial infarction, ischemic stroke, or peripheral vascular disease. Studies were included only when they adhered to specific diagnostic criteria for ischemic events and met the published methodological criteria. Odds ratios (ORs) with accompanying 95% CIs were calculated for each mutation and clinical end points with a random-effects model (DerSimonian and Laird method). RESULTS The association between inherited gene mutations and arterial ischemic events was modest: factor V Leiden mutation (OR, 1.21; 95% CI, 0.99-1.49), PT G20210A mutation (OR, 1.32; 95% CI, 1.03-1.69), and MTHFR TT mutation (OR, 1.20; 95% CI, 1.02-1.41). Subgroup analyses of younger patients (<55 years old) and of women revealed slightly stronger associations overall. CONCLUSIONS Genetic abnormalities specific to factor V, prothrombin,and homocysteine metabolism increase the risk for myocardial infarction and ischemic stroke, particularly among younger patients and women. Because the overall association is only modest, screening studies should be limited to carefully selected patient populations. The individual propensity for arterial and venous thrombosis is likely influenced by differing local mechanisms, systemic mechanisms, or both.
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Affiliation(s)
- Robert J Kim
- Department of Internal Medicine, University of Massachusetts-Memorial Medical Center, Worcester, Mass, USA
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Karttunen V, Alfthan G, Hiltunen L, Rasi V, Kervinen K, Kesäniemi YA, Hillbom M. Risk factors for cryptogenic ischaemic stroke. Eur J Neurol 2002; 9:625-32. [PMID: 12453078 DOI: 10.1046/j.1468-1331.2002.00464.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
This case-control study was designed to identify risk factors for cryptogenic brain infarction. We assessed the frequency of prothrombotic states, homocysteine, lipoprotein (a) [Lp(a)] and other lipids and the apolipoprotein E phenotype together with conventional risk factors in 46 patients (19 women and 27 men) with cryptogenic brain infarction aged from 15 to 60 years and in 104 community-based controls. Multivariate odds ratios (ORs) for risk factors and 95% CIs were calculated by logistic regression. Hypertension (OR 4.5; 95% CI, 1.5-13.2; P = 0.006), current smoking (OR 2.9; 95% CI, 1.2-6.8; P = 0.012), low HDL cholesterol (HDL-C) (OR 5.4; 95% CI, 1.1-25.5; P = 0.035) and high clotting factor VIII activity (OR 3.6; 95% CI, 1.1-12.2; P = 0.041) were variables associated with cryptogenic brain infarction. These risk factors were not equally frequent in women and men. Low HDL-C and high factor VIII activity in the women, and hypertension, current smoking and a low level of plasma folate in the men were risk factors for cryptogenic stroke. Several of the observed risk factors for cryptogenic brain infarction were lifestyle-associated, which emphasizes the role of health education in addition to pharmacological treatment in the prevention of stroke.
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Affiliation(s)
- V Karttunen
- Department of Neurology, Oulu University Central Hospital, Helsinki, Finland.
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Shuaib A, Yang Y, Nakada MT, Li Q, Yang T. Glycoprotein IIb/IIIa antagonist, murine 7E3 F(ab') 2, and tissue plasminogen activator in focal ischemia: evaluation of efficacy and risk of hemorrhage with combination therapy. J Cereb Blood Flow Metab 2002; 22:215-22. [PMID: 11823719 DOI: 10.1097/00004647-200202000-00009] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Tissue hypoperfusion during cerebral ischemia results from occlusion of large and small vessels. Combination treatment strategies using fibrinolytics to thrombolyse an embolic clot and antiplatelet agents to prevent reocclusion and the formation of new platelet thrombi in the microcirculation may offer advantages over single-agent therapy. The authors report on the effects of tissue plasminogen activator (rt-PA), a glycoprotein (GP) IIb/IIIa receptor antagonist, 7E3 F(ab') 2, or a combination of the two agents in a focal embolic model of cerebral ischemia in Wistar rats. Focal ischemia was produced by introducing an autologous thrombus into the right side middle cerebral artery. Forty-six male Wistar rats were randomly divided into 6 groups: control (n = 8), 7E3 F(ab') 2 (n = 9, 6 mg/kg), rt-PA (n = 9, 10 mg/kg), rt-PA (n = 6, 20 mg/kg), and 7E3 F(ab') 2 with either 10 mg/kg (n = 10) (low-dose combination) or 20 mg/kg (n = 6) (high-dose combination) rt-PA. Evaluation of neurobehavioral scores, cerebral angiography, bleeding time, and measurement of brain infarction volume were used to determine efficacy. All actively treated groups showed a significant reduction in the infarct volume. Animals treated with 7E3 F(ab') 2 showed reduced infarction volumes (24.0 +/- 5.1%) compared with controls (42.43 +/- 5.6%, P < 0.02). Treatment with rt-PA significantly reduced infarction volume (20.7 +/- 3.3, = 0.01) at 10 mg/kg and at 20 mg/kg (19.5 +/- 8.2%, P < 0.05). Compared with vehicle-treated animals, the low-dose combination (16.4 +/- 5.5, P < 0.003) and high-dose combination (23.7 +/- 6.2%, P < 0.05) showed significant reduction in infarction volume. Cerebral angiography revealed significantly better recanalization in the combination group (5/6 animals in the high dose and 4/6 in low dose) compared with animals treated with 7E3 F(ab') 2 (3/10) or rt-PA alone (2/6). Bleeding time significantly increased from 11.25 +/- 1.9 minutes in the control group to 17 +/- 3.1 minutes in the rt-PA group, 24.5 +/- 2.6 minutes in the 7E3 F(ab') 2 group, 25.7 +/- 3.1 minutes in the low-dose combination group, and 32.5 +/- 4.7 minutes in the high-dose combination group. The incidence of intercerebral hemorrhage was highest in the high-dose combination group (6 of 6 animals) and lowest in the single treatment with 7E3 F(ab') 2 alone (1 of 10 animals) ( P < 0.05). Our data show that murine 7E3 F(ab') 2 alone has therapeutic effects when used after cerebral ischemia. Although this study suggests that higher doses of thrombolytic combined with anti-GPIIb/IIIa therapy may increases the risk of intracranial hemorrhage, the data also support the notion that anti-GPIIb/IIIa agents can safely be combined with low doses of thrombolytic agent to produce significant attenuation of neuronal damage with no increase in the incidence of cerebral hemorrhage.
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Affiliation(s)
- Ashfaq Shuaib
- Acute Stroke Program, Neurology Division, University of Alberta Hospital, Edmonton, Alberta, Canada
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Ford ES, Smith SJ, Stroup DF, Steinberg KK, Mueller PW, Thacker SB. Homocyst(e)ine and cardiovascular disease: a systematic review of the evidence with special emphasis on case-control studies and nested case-control studies. Int J Epidemiol 2002; 31:59-70. [PMID: 11914295 DOI: 10.1093/ije/31.1.59] [Citation(s) in RCA: 157] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
BACKGROUND Elevated concentrations of homocyst(e)ine are thought to increase the risk of vascular diseases including coronary heart disease and cerebrovascular disease. METHODS We searched MEDLINE (1966-1999), EMBASE (1974-1999), SciSearch (1974- 1999), and Dissertation Abstracts (1999) for articles and theses about homocyst(e)ine concentration and coronary heart disease and cerebrovascular disease. RESULTS We included 57 publications (3 cohort studies, 12 nested case-control studies, 42 case-control studies) that reported results on 5518 people with coronary heart disease (11,068 control subjects) and 1817 people with cerebrovascular disease (4787 control subjects) in our analysis. For coronary heart disease, the summary odds ratios (OR) for a 5-micromol/l increase in homocyst(e)ine concentration were 1.06 (95% CI : 0.99-1.13) for 2 publications of cohort studies, 1.23 (95% CI : 1.07-1.41) for 10 publications of nested case-control studies, and 1.70 (95% CI : 1.50-1.93) for 26 publications of case-control studies. For cerebrovascular disease, the summary OR for a 5-micromol/l increase in homocyst(e)ine concentration were 1.10 (95% CI : 0.94-1.28) for 2 publications of cohort studies, 1.58 (95% CI : 1.35-1.85) for 5 publications of nested case-control studies, and 2.16 (95% CI : 1.65-2.82) for 17 publications of case-control studies. CONCLUSIONS Prospective studies offer weaker support than case-control studies for an association between homocyst(e)ine concentration and cardiovascular disease. Although other lines of evidence support a role for homocyst(e)ine in the pathogenesis of cardiovascular disease, more information from prospective epidemiological studies or clinical trials is needed to clarify this role.
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Affiliation(s)
- Earl S Ford
- Division of Nutrition and Physical Activity, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, GA 30341, USA
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Puddey IB, Zilkens RR, Croft KD, Beilin LJ. Alcohol and endothelial function: a brief review. Clin Exp Pharmacol Physiol 2001; 28:1020-4. [PMID: 11903307 DOI: 10.1046/j.1440-1681.2001.03572.x] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
1. In spite of the dose-related effects of alcohol consumption to increase blood pressure, regular light to moderate alcohol intake appears to confer protection against both coronary artery disease and ischaemic stroke. In contrast, heavy alcohol consumption increases the risk of coronary artery disease and the risk of both haemorrhagic and ischaemic stroke. 2. Effects of alcohol consumption on endothelial cell function may be relevant to these disparate effects on cardiovascular outcomes. In in vitro animal studies, low doses of alcohol have been demonstrated to increase release of nitric oxide and augment endothelium-mediated vasodilatation, whereas higher doses impair endothelium-dependent relaxation responses. In contrast, chronic administration of alcohol to rats has generally been associated with tolerance to the acute inhibitory effects of alcohol on endothelium-mediated vasodilatation and may even result in augmentation of such responses. 3. The few human studies to date that have examined the effects of alcohol on endothelial function have focused on postischaemic flow-mediated dilation of the brachial artery (FMD). Although blunted FMD responses have been reported in alcoholic subjects, acute administration of alcohol or short-term interventions to reduce alcohol intake have had no effect to either improve or impair FMD. 4. Further studies in humans assessing acute and longer term dose-related effects of alcohol on endothelial function in both conduit and resistance vessels will be necessary if the relevance of the findings from in vitro and in vivo animal studies are to be understood in the context of the complex interrelationships of alcohol with cardiovascular disease.
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Affiliation(s)
- I B Puddey
- University of Western Australia, Department of Medicine, Royal Perth Hospital, Western Australia, Australia.
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Abstract
OBJECTIVE To determine total serum homocysteine levels in a large group of patients with migraine with and without aura. BACKGROUND Hypercoagulable state is a known risk factor for stroke in the young. The existence of a hypercoagulable state has been postulated in migraine and homocysteinemia with young-onset stroke. To the best of our knowledge, blood homocysteine has not been studied in a significant number of patients with various forms of migraine. METHODS Total serum homocysteine was measured with high-performance liquid chromatography in 78 patients with migraine and in 126 age- and sex-matched healthy volunteers. RESULTS Seventy-eight patients aged 18 to 65 years were studied: 22 with migraine with aura and 56 with migraine without aura. Only 1 man had significantly elevated blood homocysteine (38.6 micromol/L), while another had a borderline elevation (15.8 micromol/L) (reference value for both sexes in our laboratory is 4 to 14 micromol/L). Both patients suffered from migraine without aura. CONCLUSIONS Blood homocysteine is not elevated in migraine.
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Affiliation(s)
- R Hering-Hanit
- Headache Unit, Sackler Faculty of Medicine, Tel Aviv University, Israel
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Abstract
During the past year epidemiological studies have linked elevated plasma total homocysteine concentrations with an increased risk of ischaemic stroke because of arterial disease. Laboratory studies have further explored the mitogenic effects of total homocysteine on vascular smooth muscle, and cytotoxic and thrombophilic effects on vascular endothelium. Also, a clinical trial has shown that lowering total homocysteine by means of multivitamin therapy decreases the rate of abnormal exercise electrocardiography tests. However, it remains to be determined whether lowering total homocysteine prevents hard clinical outcome events, such as stroke and other serious vascular events. An alternative explanation for the observed association between elevated total homocysteine and stroke is a confounding effect of factors associated with hyperhomocysteinaemia (e.g. cigarette smoking, renal impairment, an atherogenic diet, cystine deficiency, folate deficiency) or perhaps even the acute vascular events themselves, whereby the tissue damage temporarily increases total homocysteine levels. The results of ongoing clinical trials in stroke patients to determine the impact of multivitamin therapy on recurrent stroke and other serious vascular events are awaited.
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Affiliation(s)
- G J Hankey
- Stroke Unit, Royal Perth Hospital, Western Australia and Department of Medicine, University of Western Australia.
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Abstract
Data from studies of 337 children and 1606 young adults are summarized to identify the major causes of stroke in these age groups. In children under 15 years of age, stroke occurs in patients with congenital heart disease, nonatherosclerotic vasculopathies, infection, and hematologic defects like sickle cell disease. In patients 15 to 35 years of age, dissection, cardioembolism, nonatheroslerotic vasculopathies, and prothrombotic states cause a significant percentage of strokes. In adults over 35 years of age, traditional atherosclerotic risk factors predominate. Lifestyle choices (e.g., cigarette smoking, alcohol consumption, and illicit drug use) can significantly increase the rate of stroke among young adults in a community. Limited access to healthcare may increase the role of infectious disease and peripartum complications.
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Affiliation(s)
- B H Bendixen
- Department of Neurology, Albert Einstein College of Medicine, 1300 Morris Park Avenue, Bronx, NY 10461, USA
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Abstract
Coronary heart disease is the leading cause of death in the developed world. Current surgical and pharmacological interventions are essentially palliative and interest in preventive strategies, particularly through nutrition and avoidance of tobacco has increased in recent years. Basic scientific, clinical and epidemiological evidence indicates a positive association between the plasma level of the amino acid homocysteine and vascular disease. Homocysteine levels are inversely related to both intake and plasma levels of folate. Less strong evidence indicates an inverse relationship between folate intake and coronary heart disease risk. It is likely that current estimates of dietary folate requirements are lower than optimal. Folic acid supplementation reliably reduces homocysteine levels, and may also modify endothelial function independent of this effect on homocysteine. Such treatment is cheap and appears to be essentially free of risk. However, until present randomised control trials are complete, it will not be known definitively whether or not increasing folate intake reduces cardiovascular risk.
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Affiliation(s)
- I M Graham
- Trinity College, and Adelaide & Meath Hospital, Incorporating the National Children's Hospital, Dublin, Ireland.
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