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Original Investigation |

Hyperhomocystinemia:  A Risk Factor or a Consequence of Coronary Heart Disease? FREE

Paul Knekt, PhD; Antti Reunanen, MD, PhD; Georg Alfthan, PhD; Markku Heliövaara, MD, PhD; Harri Rissanen; Jukka Marniemi, PhD; Arpo Aromaa, MD, PhD
[+] Author Affiliations

From the National Public Health Institute, Helsinki, Finland (Drs Knekt, Reunanen, Alfthan, Heliövaara, and Aromaa and Mr Rissanen); and the Social Insurance Institution, Turku, Finland (Dr Marniemi).


Arch Intern Med. 2001;161(13):1589-1594. doi:10.1001/archinte.161.13.1589.
Text Size: A A A
Published online

Background  Mild hyperhomocystinemia has been suggested as an indicator of an increased risk of cardiovascular disease.

Objective  To examine whether serum homocysteine concentration is a predictor of coronary heart disease (CHD) events.

Methods  A case-control study, nested in a population-based cohort study was used. During a follow-up of 13 years, 166 major coronary events (death from CHD or nonfatal myocardial infarction) occurred in men with evidence of heart disease at baseline and 272 events in men without a history of heart disease. Two controls per case were selected by individual matching.

Results  Among men with known heart disease at baseline, the relative risk (95% confidence interval) of CHD events adjusted for age, smoking, hypertension, diabetes mellitus, serum cholesterol level, body mass index, and alcohol consumption was 2.23 (95% confidence interval, 1.03-4.85) in the highest serum homocysteine quintile compared with the lowest quintile. Among the men free of heart disease at baseline, the corresponding relative risk was 0.90 (95% confidence interval, 0.51-1.60).

Conclusions  This prospective study does not support the hypothesis that a high concentration of serum homocysteine is a risk factor for coronary events in a population free of heart disease. However, it does suggest that mild hyperhomocystinemia predicts secondary coronary events in men with heart disease, possibly as a consequence of atherosclerotic changes.

AN ELEVATED plasma concentration of homocysteine has been suggested to be a new important risk factor of atherosclerotic vascular disease amenable to preventive actions.13 Experimental evidence suggests that an increased concentration of homocysteine may result in vascular changes through several mechanisms.46 Homocysteine has been shown to impair vascular endothelial cell function and even induce cell damage. In addition, homocysteine is a stimulator of smooth muscle cell proliferation. It may also induce oxidation of low-density lipoproteins. Thrombogenesis is enhanced by a high concentration of homocysteine, increased adherence of platelets, inhibition of protein C activation, expression of thrombomodulin, and decreased activity of tissue-type plasminogen activator. Several case-control studies have provided consistent evidence showing higher serum homocysteine concentrations in patients with various atherosclerotic diseases compared with healthy control subjects.1,5,7,8 Accordingly, the homocysteine risk factor hypothesis has won large acceptance and several authors1,912 have argued that screening and preventive measures should be undertaken at least in persons with known atherosclerotic disease. Folic acid is known to be an effective factor in reducing elevated levels of serum homocysteine, and several intervention studies have been initiated to investigate the effect of supplementation of the vitamin on hyperhomocystinemia risk and in secondary prevention among individuals with known atherosclerotic diseases.13,14

The fact remains that the hypothesis has been strongly based on biological mechanisms mostly demonstrated by in vitro studies and that the human evidence mainly comes from case-control studies whereas population-based prospective cohort studies have given conflicting results. Several cohort studies showed a significantly elevated risk of coronary heart disease (CHD) at higher serum homocysteine levels.1521 Other studies demonstrated an increased risk only in subpopulations,22 for short follow-up periods,23 or only when the results were not adjusted for all potential confounding factors.24,25 A complete lack of association between hyperhomocystinemia and CHD has also been reported.2629 Thus, despite the flourishing literature on homocysteine as a potential new vascular risk factor, uncertainty still prevails about whether hyperhomocystinemia reflects the primary cause of vascular disease or is involved in the development of secondary events in populations suffering from atherosclerosis.

To further elucidate the role of homocysteine as a risk factor for CHD events, we examined its predictive value in a prospective population study with a long follow-up and large enough sample size to enable separate consideration of future CHD cases with and without heart disease at the baseline examination.

A total of 3471 men, aged between 45 and 64 years, participated in the Mobile Clinic Health Examination Survey that was carried out in various regions of Finland from January 1, 1973 through December 31, 1976.30 The individuals participated with the understanding that these data would be used in scientific research. A self-administered questionnaire provided information about the history of diseases, medicine use, recreational physical activity, alcohol consumption, and smoking habits. The answers to this questionnaire were checked and, if necessary, specially trained nurses assisted subjects in its completion. Casual blood pressure was registered, and the subjects were classified into 4 hypertension categories based on their systolic and diastolic blood pressures and their use of antihypertensive drugs.31 Body height and weight were measured and the body mass index (calculated as weight in kilograms divided by the square of height in meters) was computed. Serum cholesterol concentrations were determined from serum samples after 13 weeks of storage at −20°C with an autoanalyzer modification of the Burchard-Liebermann reaction. Patients with heart disease were identified based on disease history. Patients with diabetes mellitus were identified on the basis of disease history, use of antidiabetic medication, or the results of an oral glucose tolerance test. A history of heart disease was obtained using specific questions: Have you had, according to a physician's diagnosis, myocardial infarction, angina pectoris, heart failure, or valvular or congenital heart disease? Of the 3471 men, 884 reported a history of heart disease.

Nonfatal cases of myocardial infarction (International Classification of Diseases, Eighth Revision code 410) were identified by linking the study population to the nationwide hospital discharge register using a unique personal identification number.32 The fatal cases of CHD (International Classification of Diseases, Eighth Revision codes 410-414) were identified from death certificates that were obtained for all the deceased from Statistics Finland, Helsinki. For persons with several CHD events, the first one was registered. The follow-up covered cases occurring between the baseline examination and the end of 1985. During this follow-up period 166 major CHD events (coronary deaths or myocardial infarction) occurred among the men with heart disease and 272 such events among those free of heart disease at baseline.

A nested case-control design was adopted to study the ability of the serum homocysteine level to predict major CHD events. Two controls per case were selected by individual matching using age, municipality, and presence of heart disease at baseline as matching variables. The ages were matched by nearest available matching. Matching for municipality also controlled for the time of the baseline examination and for the duration of serum sample storage.33 Serum samples for some of the controls were for different reasons unavailable and, thus, the final numbers of controls were 311 and 524 for those cases with and without heart disease at baseline, respectively.

The serum samples were stored at −20°C until 1996 when they were used in the present study. The serum samples for each case and individually matched controls were analyzed simultaneously in random order independently of case-control status of which the laboratory personnel were unaware. The levels of total serum homocysteine, cysteine, and cysteinylglycine were determined by a modification of the high-pressure liquid chromatographic method described by Ubbink et al.34 Our mobile phase was modified to consist of 0.37-mol/L acetate and 0.5% methanol, pH 4.15. The peak heights were calibrated using a secondary serum standard. The precision between each series for an in-house serum pool was 3.3% at a level of 6.5 µmol/L. The accuracy was verified by participating in an interlaboratory quality control scheme in which the bias was null for serum at 9.5 µmol/L and +1% for serum at 38.1 µmol/L.35

The conditional logistic model was used to estimate the relative risks (as odds ratios) of CHD events between quintiles (based on the distribution among all controls) of serum homocysteine.36 The effects of potential confounding factors were adjusted for by including them in the model. Test for trends was performed by including homocysteine as a continuous variable in the model. Age-adjusted mean levels of potential confounding factors at baseline in quintiles of serum homocysteine were estimated using the general linear model.37

In men free of heart disease at baseline, differences were observed between subjects with incident CHD events and their controls in several (smoking, hypertension, diabetes mellitus, body mass index, serum cholesterol level, and serum triglyceride levels), but not all, (leisure time physical activity and alcohol consumption) cardiovascular risk factors (Table 1). No differences were observed for the levels of serum homocysteine, cysteine, or cysteinylglycine. The differences in cardiovascular risk factors between cases and controls in men with known heart disease at baseline were similar. In that subpopulation, however, the mean serum homocysteine concentration was significantly (9%) higher in cases than in controls. The age-adjusted serum homocysteine level among future CHD events with known heart disease at baseline was 11% (P = .01) higher than in those future CHD events free of heart disease at baseline.

Table Graphic Jump LocationTable 1. Mean Values of Different Variables in Patients With Coronary Heart Disease Events and Control Subjects

Serum homocysteine concentration increased significantly with age (Table 2). It was also directly proportional to the prevalence of arterial hypertension and to the level of serum triglycerides. Furthermore, serum homocysteine concentration was strongly associated with the serum cysteine level and weakly associated with the serum cysteinylglycine level.

Table Graphic Jump LocationTable 2. Mean Values* of Different Variables in Quartiles of Serum Homocysteine Among All Controls Combined

No association between serum homocysteine concentration and the incidence of major CHD events was observed in men originally free of heart disease (Table 3). The relative risk between individuals in the highest and lowest quintiles of serum homocysteine was 1.00 (95% confidence interval [CI], 0.61-1.63). A similar comparison between the highest and lowest deciles gave a corresponding value of 1.11 (95% CI, 0.55-2.25). In men known to have heart disease at baseline, however, there was a positive association between the serum homocysteine level and the incidence of major CHD events. The relative risk of such an event between the highest and lowest homocysteine quintiles was 2.15 (95% CI, 1.10-4.22). Adjustment for the known risk factors of CHD, ie, smoking, hypertension, diabetes mellitus, serum cholesterol level, body mass index, and alcohol consumption, did not notably alter the result (Table 3).

Table Graphic Jump LocationTable 3. Relative Risk of Coronary Heart Disease Events Between Quintiles of Serum Homocysteine*

An examination of possible effect-modification by sex, age, body mass index, smoking, hypertension, diabetes mellitus, and high body iron stores (ferritin) on the association between the homocysteine level and the risk of major CHD events generally revealed no significant interactions (data not shown). However, in men suffering from heart disease at baseline, there was a strong positive association between the homocysteine concentration and the major CHD events in the lowest tertile of serum ferritin. In this category the relative risk of CHD events between the highest and lowest quartiles of homocysteine was 7.11 (95% CI, 2.05-24.74).

A study of the association as a function of follow-up time suggested strong associations for shorter follow-up times both in men with and without heart disease at baseline. The relative risks of major CHD events between the highest and lowest quintiles of homocysteine during the first 2 years of follow-up were 4.44 (95% CI, 1.01-19.50) and 2.38 (95% CI, 0.53-10.64), respectively, in the 2 subgroups of men.

We found that an elevated serum concentration of homocysteine predicted CHD events in men with evidence of known heart disease at the baseline examination. In men without a history of heart disease, however, homocysteine did not predict future disease. Our results do not therefore corroborate the hypothesis that homocysteine concentration is a causal factor in the pathogenesis of atherosclerosis in healthy populations. Similar negative findings were reported in another prospective population study in Finland26 and in several recent cohort studies.22,24,2729 However, since the first published prospective population study showing an independent predictive effect of homocysteine concentration on myocardial infarction incidence,15 several similar positive results from prospective population studies have been reported.1621

The conflicting results may be due to several factors. First, the elevated homocysteine levels could, in fact, be a marker or consequence of atherosclerosis and, thus, have no relevance in the prediction of the disease. Particularly the earlier epidemiological evidence on the risk factor role of plasma homocysteine came mainly from case-control studies based on cases with established atherosclerosis1,3840 and, thus, is compatible with the consequence hypothesis. Our finding of an elevated CHD event risk at higher serum homocysteine levels during the first year of follow-up also in men free from heart disease at baseline could be due to the presence of symptom-free men. The conflicting results obtained from the Physicians' Health Study with short15 and longer27 follow-up can be similarly explained. Furthermore, 3 of the prospective studies reporting an elevated risk at higher serum homocysteine levels had a rather short follow-up period.16,19,20 However, in the British Regional Heart Study21 the length of follow-up was unrelated to the strength of association. An elevated serum homocysteine concentration might also be a marker of progression of the atherosclerotic process and, thus, may be a risk indicator or a risk factor among men with atherosclerotic vascular disease. Our finding demonstrating an increased subsequent CHD event risk in men with known heart disease at baseline is in accord with this hypothesis. The British Regional Heart Study21 also reported a stronger association in men with preexisting CHD at baseline than among others. Furthermore, high homocysteine levels predicted a subsequent increase in complications in patients with atherosclerotic vascular disease in other studies.41,42 The discrepant results obtained from prospective population studies could partly be explained by the existence of a varying proportion of individuals with known or unknown atherosclerotic disease at the baseline examination in some of the studies.19,20 This interpretation is also in accord with the consistent associations reported in case-control studies.

Second, the strength of association of homocysteine concentration and atherosclerosis may vary between populations. The genetic background of the Finnish population differs somewhat from that of the populations from other Western countries. Thus, some hereditary disorders common in other countries are rare in Finland, whereas many hereditary disorders occurring in Finland are rare in other countries.43,44 Homocystinuria is one of the hereditary disorders that is rare in Finland.43 As in our study, one earlier report could not find any effect of serum homocysteine concentration on the risk of atherosclerotic diseases in Finnish people free of heart disease at baseline.26 These findings could partly be explained by the rarity of genetically determined disorders in Finnish people leading to elevated levels of serum homocysteine. The strength of association may also vary from one subpopulation to another, according to single effect-modifying factors, such as sex,22 age,21 and hypertension,19 or clusters of several cardiovascular risk factors. In this study, we found no notable interactions with known cardiovascular risk factors.

Third, the serum homocysteine concentration may be associated with established risk factors and, thus, the observed association could be due to uncontrolled confounding factors. As in earlier studies,5,45 we found that age, hypertension, body mass index, and serum triglyceride levels were associated with the level of homocysteine. In the Caerphilly Prospective Study,24 in which a significantly increased risk associated with high homocysteine levels was observed, statistical significance was not reached once other risk factors were controlled for. In another British prospective study, the British United Provident Association Study,17 the significance of the association for serum homocysteine was reported after controlling only for systolic blood pressure and serum apolipoprotein B. In our study, as well as in another,21 adjustment for potential confounding factors did not appreciably alter the strength of the association.

Fourth, the lack of association may be owing to poor reliability of serum homocysteine determination. The analytical variation in our study was, however, acceptably low. The long storage of our serum samples at −20°C could potentially weaken the reliability of serum determinations. It has, however, been shown that the length of storage time apparently does not lead to alterations in homocysteine concentrations.26 Furthermore, all serum samples had undergone the same freeze-thaw history and were analyzed within a short time without knowledge of the case-control identification. The fact that we found an association among men with heart disease also suggests that the reliability of serum homocysteine determination was adequate.

Finally, although there are several possible mechanisms by which a high homocysteine level may promote pathogenesis of atherosclerosis,46 doubts of the causal role have recently been raised. Evidence has been presented that plasma homocysteine level increases after tissue damage and raised plasma levels of homocysteine promote endothelial damage and adhesion of leukocytes to the endothelial surface.47 A high plasma homocysteine level, thus, would be an indicator of continuing tissue damage and a promotor or enhancer of inflammatory thickening of vascular wall47 rather than an initiator of atherosclerosis. Causal association of hyperhomocystinemia and vascular disease has also been questioned in a recent review of epidemiological studies48 concluding in agreement with our results, that raised homocysteine level would merely be a marker of atherosclerosis and a consequence of other factors rather than a primary risk factor.

Our prospective data demonstrating the ability of high serum concentrations of homocysteine to predict secondary CHD events in middle-aged men with heart disease do not support the hypothesis that a high homocysteine concentration is a primary causal factor in the pathogenesis of atherosclerosis, but merely suggest it to be a consequence of atherosclerotic changes.

Accepted for publication December 11, 2000.

Corresponding author: Paul Knekt, PhD, National Public Health, Mannerheimintie 166, 00300 Helsinki, Finland (e-mail: paul.knekt@ktl.fi).

Boushey  CJBeresford  SAOmenn  GSMotulsky  AG A quantitative assessment of plasma homocysteine as a risk factor for vascular disease: probable benefits of increasing folic acid intakes. JAMA. 1995;2741049- 1057
Link to Article
Oakley Jr  GP Eat right and take a multivitamin. N Engl J Med. 1998;3381060- 1061
Link to Article
Omenn  GSBeresford  SAMotulsky  AG Preventing coronary heart disease: B vitamins and homocysteine. Circulation. 1998;97421- 424
Link to Article
Domagala  TBUndas  ALibura  MSzczeklik  A Pathogenesis of vascular disease in hyperhomocysteinaemia. J Cardiovasc Risk. 1998;5239- 247
Link to Article
Refsum  HUeland  PMNygård  OVollset  SE Homocysteine and cardiovascular disease. Annu Rev Med. 1998;4931- 62
Link to Article
Eikelboom  JWLonn  EGenest Jr  JHankey  GYusuf  S Homocyst(e)ine and cardiovascular disease: a critical review of the epidemiologic evidence. Ann Intern Med. 1999;131363- 375
Link to Article
Malinow  MR Hyperhomocyst(e)inemia: a common and easily reversible risk factor for occlusive atherosclerosis. Circulation. 1990;812004- 2006
Link to Article
Danesh  JLewington  S Plasma homocysteine and coronary heart disease: systematic review of published epidemiological studies. J Cardiovasc Risk. 1998;5229- 232
Link to Article
Mayer  ELJacobsen  DWRobinson  K Homocysteine and coronary atherosclerosis. J Am Coll Cardiol. 1996;27517- 527
Link to Article
Moghadasian  MHMcManus  BMFrohlich  JJ Homocyst(e)ine and coronary artery disease: clinical evidence and genetic and metabolic background. Arch Intern Med. 1997;1572299- 2308
Link to Article
Stein  JHMcBride  PE Hyperhomocysteinemia and atherosclerotic vascular disease: pathophysiology, screening, and treatment. Arch Intern Med. 1998;1581301- 1306
Link to Article
Malinow  MRBostom  AGKrauss  RM Homocyst(e)ine, diet, and cardiovascular diseases: a statement for healthcare professionals from the Nutrition Committee, American Heart Association. Circulation. 1999;99178- 182
Link to Article
Clarke  RCollins  R Can dietary supplements with folic acid or vitamin B6 reduce cardiovascular risk? design of clinical trials to test the homocysteine hypothesis of vascular disease. J Cardiovasc Risk. 1998;5249- 255
Link to Article
Homocysteine Lowering Trialists' Collaboration, Lowering blood homocysteine with folic acid based supplements: meta-analysis of randomised trials. BMJ. 1998;316894- 898
Link to Article
Stampfer  MJMalinow  MRWillett  WC  et al.  A prospective study of plasma homocyst(e)ine and risk of myocardial infarction in US physicians. JAMA. 1992;268877- 881
Link to Article
Arnesen  ERefsum  HBonaa  KHUeland  PMForde  OHNordrehaug  JE Serum total homocysteine and coronary heart disease. Int J Epidemiol. 1995;24704- 709
Link to Article
Wald  NJWatt  HCLaw  MRWeir  DGMcPartlin  JScott  JM Homocysteine and ischemic heart disease: results of a prospective study with implications regarding prevention. Arch Intern Med. 1998;158862- 867
Link to Article
Bostom  AGSilbershatz  HRosenberg  IH  et al.  Nonfasting plasma total homocysteine levels and all-cause and cardiovascular disease mortality in elderly Framingham men and women. Arch Intern Med. 1999;1591077- 1080
Link to Article
Bots  MLLauner  LJLindemans  J  et al.  Homocysteine and short-term risk of myocardial infarction and stroke in the elderly: the Rotterdam Study. Arch Intern Med. 1999;15938- 44
Link to Article
Ridker  PMManson  JEBuring  JEShih  JMatias  MHennekens  CH Homocysteine and risk of cardiovascular disease among postmenopausal women. JAMA. 1999;2811817- 1821
Link to Article
Whincup  PHRefsum  HPerry  IJ  et al.  Serum total homocysteine and coronary heart disease: prospective study in middle aged men. Heart. 1999;82448- 454
Folsom  ARNieto  FJMcGovern  PG  et al.  Prospective study of coronary heart disease incidence in relation to fasting total homocysteine, related genetic polymorphisms, and B vitamins: the Atherosclerosis Risk in Communities (ARIC) study. Circulation. 1998;98204- 210
Link to Article
Stehouwer  CDWeijenberg  MPvan den Berg  MJakobs  CFeskens  EJKromhout  D Serum homocysteine and risk of coronary heart disease and cerebrovascular disease in elderly men: a 10-year follow-up. Arterioscler Thromb Vasc Biol. 1998;181895- 1901
Link to Article
Ubbink  JBFehily  AMPickering  JElwood  PCVermaak  WJ Homocysteine and ischaemic heart disease in the Caerphilly cohort. Atherosclerosis. 1998;140349- 356
Link to Article
Kark  JDSelhub  JAdler  B  et al.  Nonfasting plasma total homocysteine level and mortality in middle-aged and elderly men and women in Jerusalem. Ann Intern Med. 1999;131321- 330
Link to Article
Alfthan  GPekkanen  JJauhiainen  M  et al.  Relation of serum homocysteine and lipoprotein(a) concentrations to atherosclerotic disease in a prospective Finnish population based study. Atherosclerosis. 1994;1069- 19
Link to Article
Chasan-Taber  LSelhub  JRosenberg  IH  et al.  A prospective study of folate and vitamin B6 and risk of myocardial infarction in US physicians. J Am Coll Nutr. 1996;15136- 143
Link to Article
Evans  RWShaten  BJHempel  JDCutler  JAKuller  LH Homocyst(e)ine and risk of cardiovascular disease in the Multiple Risk Factor Intervention Trial. Arterioscler Thromb Vasc Biol. 1997;171947- 1953
Link to Article
Verhoef  PHennekens  CHAllen  RHStabler  SPWillett  WCStampfer  MJ Plasma total homocysteine and risk of angina pectoris with subsequent coronary artery bypass surgery. Am J Cardiol. 1997;79799- 801
Link to Article
Reunanen  AAromaa  APyörälä  KPunsar  SMaatela  JKnekt  P The Social Insurance Institution's coronary heart disease study: baseline data and 5-year mortality experience. Acta Med Scand Suppl. 1983;6731- 120
Aromaa  A Kohonnut Verenpaine ja sen Kansanterveydellinen Merkitys Suomessa [Epidemiology and Public Health Impact of High Blood Pressure in Finland].  Helsinki, Finland Kansaneläkelaitoksen Julkaisuja AL1981;17
Heliövaara  MReunanen  AAromaa  AKnekt  PAho  KSuhonen  O Validity of hospital discharge data in a prospective epidemiological study on stroke and myocardial infarction. Acta Med Scand. 1984;216309- 315
Link to Article
Knekt  P Serum Alpha-Tocopherol and the Risk of Cancer.  Helsinki, Finland Publications of the Social Insurance Institution ML1988;83
Ubbink  JBHayward Vermaak  WJBissbort  S Rapid high-performance liquid chromatographic assay for total homocysteine levels in human serum. J Chromatogr. 1991;565441- 446
Link to Article
Möller  JRasmussen  KChristensen  L External quality assessment of methylmalonic acid and total homocysteine. Clin Chem. 1999;451536- 1542
Breslow  NEDay  NE Statistical methods in cancer research, volume 1: the analysis of case-control studies. IARC Sci Publ. 1980;(32)5- 338
Cohen  JCohen  P Applied Multiple Regression/Correlation Analysis for the Behavioral Sciences.  New York, NY John Wiley & Sons Inc1975;
Boers  GHSmals  AGTrijbels  FJ  et al.  Heterozygosity for homocystinuria in premature peripheral and cerebral occlusive arterial disease. N Engl J Med. 1985;313709- 715
Link to Article
Clarke  RDaly  LRobinson  K  et al.  Hyperhomocysteinemia: an independent risk factor for vascular disease. N Engl J Med. 1991;3241149- 1155
Link to Article
Graham  IMDaly  LERefsum  HM  et al. European Concerted Action Project, Plasma homocysteine as a risk factor for vascular disease. JAMA. 1997;2771775- 1781
Link to Article
Taylor Jr  LMDeFrang  RDHarris Jr  EJPorter  JM The association of elevated plasma homocyst(e)ine with progression of symptomatic peripheral arterial disease. J Vasc Surg. 1991;13128- 136
Link to Article
Nygård  ONordrehaug  JERefsum  HUeland  PMFarstad  MVollset  SE Plasma homocysteine levels and mortality in patients with coronary artery disease. N Engl J Med. 1997;337230- 236
Link to Article
Norio  R Diseases in Finland and Scandinavia. Rothscild  HRedBiocultural Aspects of Disease. Orland, Fla Academic Press Inc1981;358- 415
Peltonen  LJalanko  AVarilo  T Molecular genetics of the Finnish disease heritage. Hum Mol Genet. 1999;81913- 1923
Link to Article
Nygård  OVollset  SERefsum  H  et al. Hordaland Homocysteine Study, Total plasma homocysteine and cardiovascular risk profile. JAMA. 1995;2741526- 1533
Link to Article
Welch  GNLoscalzo  J Homocysteine and atherothrombosis. N Engl J Med. 1998;3381042- 1050
Link to Article
Dudman  NP An alternative view of homocysteine. Lancet. 1999;3542072- 2074
Link to Article
Christen  WGAjani  UAGlynn  RJHennekens  CH Blood levels of homocysteine and increased risks of cardiovascular disease: causal or casual? Arch Intern Med. 2000;160422- 434
Link to Article

Figures

Tables

Table Graphic Jump LocationTable 1. Mean Values of Different Variables in Patients With Coronary Heart Disease Events and Control Subjects
Table Graphic Jump LocationTable 2. Mean Values* of Different Variables in Quartiles of Serum Homocysteine Among All Controls Combined
Table Graphic Jump LocationTable 3. Relative Risk of Coronary Heart Disease Events Between Quintiles of Serum Homocysteine*

References

Boushey  CJBeresford  SAOmenn  GSMotulsky  AG A quantitative assessment of plasma homocysteine as a risk factor for vascular disease: probable benefits of increasing folic acid intakes. JAMA. 1995;2741049- 1057
Link to Article
Oakley Jr  GP Eat right and take a multivitamin. N Engl J Med. 1998;3381060- 1061
Link to Article
Omenn  GSBeresford  SAMotulsky  AG Preventing coronary heart disease: B vitamins and homocysteine. Circulation. 1998;97421- 424
Link to Article
Domagala  TBUndas  ALibura  MSzczeklik  A Pathogenesis of vascular disease in hyperhomocysteinaemia. J Cardiovasc Risk. 1998;5239- 247
Link to Article
Refsum  HUeland  PMNygård  OVollset  SE Homocysteine and cardiovascular disease. Annu Rev Med. 1998;4931- 62
Link to Article
Eikelboom  JWLonn  EGenest Jr  JHankey  GYusuf  S Homocyst(e)ine and cardiovascular disease: a critical review of the epidemiologic evidence. Ann Intern Med. 1999;131363- 375
Link to Article
Malinow  MR Hyperhomocyst(e)inemia: a common and easily reversible risk factor for occlusive atherosclerosis. Circulation. 1990;812004- 2006
Link to Article
Danesh  JLewington  S Plasma homocysteine and coronary heart disease: systematic review of published epidemiological studies. J Cardiovasc Risk. 1998;5229- 232
Link to Article
Mayer  ELJacobsen  DWRobinson  K Homocysteine and coronary atherosclerosis. J Am Coll Cardiol. 1996;27517- 527
Link to Article
Moghadasian  MHMcManus  BMFrohlich  JJ Homocyst(e)ine and coronary artery disease: clinical evidence and genetic and metabolic background. Arch Intern Med. 1997;1572299- 2308
Link to Article
Stein  JHMcBride  PE Hyperhomocysteinemia and atherosclerotic vascular disease: pathophysiology, screening, and treatment. Arch Intern Med. 1998;1581301- 1306
Link to Article
Malinow  MRBostom  AGKrauss  RM Homocyst(e)ine, diet, and cardiovascular diseases: a statement for healthcare professionals from the Nutrition Committee, American Heart Association. Circulation. 1999;99178- 182
Link to Article
Clarke  RCollins  R Can dietary supplements with folic acid or vitamin B6 reduce cardiovascular risk? design of clinical trials to test the homocysteine hypothesis of vascular disease. J Cardiovasc Risk. 1998;5249- 255
Link to Article
Homocysteine Lowering Trialists' Collaboration, Lowering blood homocysteine with folic acid based supplements: meta-analysis of randomised trials. BMJ. 1998;316894- 898
Link to Article
Stampfer  MJMalinow  MRWillett  WC  et al.  A prospective study of plasma homocyst(e)ine and risk of myocardial infarction in US physicians. JAMA. 1992;268877- 881
Link to Article
Arnesen  ERefsum  HBonaa  KHUeland  PMForde  OHNordrehaug  JE Serum total homocysteine and coronary heart disease. Int J Epidemiol. 1995;24704- 709
Link to Article
Wald  NJWatt  HCLaw  MRWeir  DGMcPartlin  JScott  JM Homocysteine and ischemic heart disease: results of a prospective study with implications regarding prevention. Arch Intern Med. 1998;158862- 867
Link to Article
Bostom  AGSilbershatz  HRosenberg  IH  et al.  Nonfasting plasma total homocysteine levels and all-cause and cardiovascular disease mortality in elderly Framingham men and women. Arch Intern Med. 1999;1591077- 1080
Link to Article
Bots  MLLauner  LJLindemans  J  et al.  Homocysteine and short-term risk of myocardial infarction and stroke in the elderly: the Rotterdam Study. Arch Intern Med. 1999;15938- 44
Link to Article
Ridker  PMManson  JEBuring  JEShih  JMatias  MHennekens  CH Homocysteine and risk of cardiovascular disease among postmenopausal women. JAMA. 1999;2811817- 1821
Link to Article
Whincup  PHRefsum  HPerry  IJ  et al.  Serum total homocysteine and coronary heart disease: prospective study in middle aged men. Heart. 1999;82448- 454
Folsom  ARNieto  FJMcGovern  PG  et al.  Prospective study of coronary heart disease incidence in relation to fasting total homocysteine, related genetic polymorphisms, and B vitamins: the Atherosclerosis Risk in Communities (ARIC) study. Circulation. 1998;98204- 210
Link to Article
Stehouwer  CDWeijenberg  MPvan den Berg  MJakobs  CFeskens  EJKromhout  D Serum homocysteine and risk of coronary heart disease and cerebrovascular disease in elderly men: a 10-year follow-up. Arterioscler Thromb Vasc Biol. 1998;181895- 1901
Link to Article
Ubbink  JBFehily  AMPickering  JElwood  PCVermaak  WJ Homocysteine and ischaemic heart disease in the Caerphilly cohort. Atherosclerosis. 1998;140349- 356
Link to Article
Kark  JDSelhub  JAdler  B  et al.  Nonfasting plasma total homocysteine level and mortality in middle-aged and elderly men and women in Jerusalem. Ann Intern Med. 1999;131321- 330
Link to Article
Alfthan  GPekkanen  JJauhiainen  M  et al.  Relation of serum homocysteine and lipoprotein(a) concentrations to atherosclerotic disease in a prospective Finnish population based study. Atherosclerosis. 1994;1069- 19
Link to Article
Chasan-Taber  LSelhub  JRosenberg  IH  et al.  A prospective study of folate and vitamin B6 and risk of myocardial infarction in US physicians. J Am Coll Nutr. 1996;15136- 143
Link to Article
Evans  RWShaten  BJHempel  JDCutler  JAKuller  LH Homocyst(e)ine and risk of cardiovascular disease in the Multiple Risk Factor Intervention Trial. Arterioscler Thromb Vasc Biol. 1997;171947- 1953
Link to Article
Verhoef  PHennekens  CHAllen  RHStabler  SPWillett  WCStampfer  MJ Plasma total homocysteine and risk of angina pectoris with subsequent coronary artery bypass surgery. Am J Cardiol. 1997;79799- 801
Link to Article
Reunanen  AAromaa  APyörälä  KPunsar  SMaatela  JKnekt  P The Social Insurance Institution's coronary heart disease study: baseline data and 5-year mortality experience. Acta Med Scand Suppl. 1983;6731- 120
Aromaa  A Kohonnut Verenpaine ja sen Kansanterveydellinen Merkitys Suomessa [Epidemiology and Public Health Impact of High Blood Pressure in Finland].  Helsinki, Finland Kansaneläkelaitoksen Julkaisuja AL1981;17
Heliövaara  MReunanen  AAromaa  AKnekt  PAho  KSuhonen  O Validity of hospital discharge data in a prospective epidemiological study on stroke and myocardial infarction. Acta Med Scand. 1984;216309- 315
Link to Article
Knekt  P Serum Alpha-Tocopherol and the Risk of Cancer.  Helsinki, Finland Publications of the Social Insurance Institution ML1988;83
Ubbink  JBHayward Vermaak  WJBissbort  S Rapid high-performance liquid chromatographic assay for total homocysteine levels in human serum. J Chromatogr. 1991;565441- 446
Link to Article
Möller  JRasmussen  KChristensen  L External quality assessment of methylmalonic acid and total homocysteine. Clin Chem. 1999;451536- 1542
Breslow  NEDay  NE Statistical methods in cancer research, volume 1: the analysis of case-control studies. IARC Sci Publ. 1980;(32)5- 338
Cohen  JCohen  P Applied Multiple Regression/Correlation Analysis for the Behavioral Sciences.  New York, NY John Wiley & Sons Inc1975;
Boers  GHSmals  AGTrijbels  FJ  et al.  Heterozygosity for homocystinuria in premature peripheral and cerebral occlusive arterial disease. N Engl J Med. 1985;313709- 715
Link to Article
Clarke  RDaly  LRobinson  K  et al.  Hyperhomocysteinemia: an independent risk factor for vascular disease. N Engl J Med. 1991;3241149- 1155
Link to Article
Graham  IMDaly  LERefsum  HM  et al. European Concerted Action Project, Plasma homocysteine as a risk factor for vascular disease. JAMA. 1997;2771775- 1781
Link to Article
Taylor Jr  LMDeFrang  RDHarris Jr  EJPorter  JM The association of elevated plasma homocyst(e)ine with progression of symptomatic peripheral arterial disease. J Vasc Surg. 1991;13128- 136
Link to Article
Nygård  ONordrehaug  JERefsum  HUeland  PMFarstad  MVollset  SE Plasma homocysteine levels and mortality in patients with coronary artery disease. N Engl J Med. 1997;337230- 236
Link to Article
Norio  R Diseases in Finland and Scandinavia. Rothscild  HRedBiocultural Aspects of Disease. Orland, Fla Academic Press Inc1981;358- 415
Peltonen  LJalanko  AVarilo  T Molecular genetics of the Finnish disease heritage. Hum Mol Genet. 1999;81913- 1923
Link to Article
Nygård  OVollset  SERefsum  H  et al. Hordaland Homocysteine Study, Total plasma homocysteine and cardiovascular risk profile. JAMA. 1995;2741526- 1533
Link to Article
Welch  GNLoscalzo  J Homocysteine and atherothrombosis. N Engl J Med. 1998;3381042- 1050
Link to Article
Dudman  NP An alternative view of homocysteine. Lancet. 1999;3542072- 2074
Link to Article
Christen  WGAjani  UAGlynn  RJHennekens  CH Blood levels of homocysteine and increased risks of cardiovascular disease: causal or casual? Arch Intern Med. 2000;160422- 434
Link to Article

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