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J Danesh

Publications and source records attributed to J Danesh.

At least 19 recordsLinked to original sources
PubMed2006

Associations between apolipoprotein B, apolipoprotein AI, the apolipoprotein B/AI ratio and coronary heart disease: a literature-based meta-analysis of prospective studies.

OBJECTIVES: To assess associations of circulating levels of apolipoprotein (apo) AI, apoB and the apoB/AI ratio (apoB/A) with risk of incident coronary heart disease (CHD). DESIGN: Literature-based meta-analysis of prospective studies. DATA SOURCES: Prospective studies in essentially general populations that reported on associations between apoAI, apoB or apoB/A and first incident CHD outcomes. Studies were identified by computer-based searches and by manual searches of the relevant literature. RESULTS: Data from 23 relevant studies were identified. For apoAI, with 6333 CHD cases in 21 studies, comparison of individuals in the bottom third with those in the top third of baseline values yielded a combined relative risk of 1.62 (95% confidence interval: 1.43-1.83), i.e. an inverse association. For apoB, a combined analysis of 6320 CHD cases from 19 studies gave a relative risk of 1.99 (1.65-2.39) for a comparison of individuals in the top third versus those in the bottom third of baseline values. For apoB/A, with 3730 CHD cases from seven studies, a comparison of individuals in the top third versus the bottom third of baseline values gave a combined relative risk of 1.86 (1.55-2.22). These associations were somewhat stronger following correction for within-person variations in apolipoprotein levels. There was evidence of heterogeneity amongst the published studies, but it was only partly explained by available study-level characteristics. CONCLUSIONS: The present quantitative review suggests the existence of moderately strong associations between baseline levels of each of apoAI, apoB, and apoB/A and risk of CHD. More detailed analysis, perhaps based on individual participant data from prospective studies, could help to overcome several limitations in the present review and to clarify any relevance of these apolipoproteins to disease prediction and aetiology.

Apolipoprotein A-I↗
PubMed2004

Tissue plasminogen activator antigen and coronary heart disease. Prospective study and meta-analysis.

AIMS: To determine whether circulating tissue plasminogen activator (t-PA) antigen concentrations are prospectively related to risk of coronary heart disease (CHD) in the general population. METHODS AND RESULTS: We measured baseline concentrations of t-PA antigen in the stored serum samples of 606 CHD cases and 1227 controls 'nested' in a prospective cohort of 5661 men monitored for 16 years, and conducted a meta-analysis of previous relevant studies to place our findings in context. Tissue plasminogen activator antigen values were strongly correlated with several vascular risk factors, including serum lipids, body mass index, alcohol consumption, and markers of systemic inflammation. In a comparison of men in the top third compared with those in the bottom third of baseline t-PA antigen values, the odds ratio for CHD was 2.20 (95% confidence interval (CI) 1.70-2.85) after adjustment for age and town only, but this fell to 1.48 (1.09-2.01) after further adjustment. Analysis of t-PA as a continuous variable gave similar results. Similarly, when published information on all seven available prospective cohort studies in general populations (2119 cases and 8832 controls in total) was synthesized, the combined odds ratio was 2.18 (1.77-2.69) after adjustment for age and sex only, and this fell to 1.47 (1.19-1.81) after further adjustment. CONCLUSION: Although there is a statistically significant association between circulating concentrations of t-PA antigen and subsequent CHD, additional studies are needed to determine to what extent this is independent from more established risk factors.

Adult↗
PubMed2002

Chlamydia pneumoniae IgA titres and coronary heart disease; prospective study and meta-analysis.

AIMS: To examine associations between Chlamydia pneumoniae IgA titres and incident coronary heart disease, and to compare them with associations previously reported between C. pneumoniae IgG titres and coronary heart disease. METHODS AND RESULTS: We measured serum concentrations of C. pneumoniae IgA antibodies in 502 coronary heart disease cases and in 1005 age- and town-matched controls 'nested' in a community-based prospective study of 5661 British men (mean follow-up in controls, 16 years), and conducted a meta-analysis of published prospective studies to place our findings in context. Two hundred and twenty-one (44%) of the cases were in the top third of C. pneumoniae IgA titres compared with 336 (33%) of the controls, yielding an odds ratio for coronary heart disease of 1.84 (95% confidence interval 1.40-2.43) which was largely unchanged after adjustment. In aggregate, the present study and nine previously reported prospective studies of C. pneumoniae IgA titres involved 2283 cases, yielding a combined odds ratio for coronary heart disease of 1.25 (1.03-1.53), with no significant heterogeneity among the ten studies (chi(2)9=7.8; P>0.1). This combined odds ratio is compatible with that previously reported for C. pneumoniae IgG titres and coronary heart disease (1.15, 0.97-1.36). CONCLUSION: Neither C. pneumoniae IgA titres nor IgG titres are strongly predictive of coronary heart disease in the general population.

Adult↗
PubMed2002

von Willebrand factor and coronary heart disease: prospective study and meta-analysis.

AIMS: To determine whether circulating von Willebrand factor concentrations are prospectively related to risk of coronary heart disease in the general population. METHODS AND RESULTS: We measured baseline von Willebrand factor values in the stored serum samples of 625 men with major coronary events and in 1266 controls 'nested' in a prospective study of 5661 men aged 40-59 years, recruited from general practices in 18 British towns in 1978-1980 and followed up for 16 years for fatal coronary heart disease and non-fatal myocardial infarction. We conducted a meta-analysis of previous relevant studies to place our results in context. Men in the top third of baseline von Willebrand factor values (tertile cutoff >126 IU.dl(-1)) had an odds ratio for coronary heart disease of 1.83 (95% confidence interval 1.43-2.35; 2P <0.0001) compared with those in the bottom third (tertile cutoff <90 IU.dl(-1)), after adjustments for age and town. The odds ratio was little changed after further adjustment for risk factors (1.82, 95% CI 1.37-2.41), and was not significantly different in an analysis restricted to the 404 cases and 1007 controls without baseline evidence of coronary heart disease (odds ratio 1.53, 95% CI 1.10-2.12). A meta-analysis of all relevant population-based prospective studies (including the present study) yielded a combined odds ratio of 1.5 (95% CI 1.1-2.0). von Willebrand factor values were strongly correlated with Helicobacter pylori seropositivity and circulating concentrations of C-reactive protein (2 P<0.0001 for each), but not with smoking, blood lipids, or most other measured risk factors. CONCLUSION: Though circulating von Willebrand factor concentrations may be associated with incident coronary heart disease, further studies are needed to determine the extent to which this is causal.

Adult↗
PubMed2001

Soluble adhesion molecules and prediction of coronary heart disease: a prospective study and meta-analysis.

BACKGROUND: Previous studies have suggested that circulating concentrations of soluble adhesion molecules are useful predictors of risk of coronary heart disease (CHD). Larger studies are needed, however, to test this hypothesis. METHODS: We measured serum concentrations of four soluble cell adhesion molecules (intercellular adhesion molecule-1 [ICAM-1], vascular cell adhesion molecule-1 [VCAM-1], E-selectin, and P-selectin) in the stored baseline serum samples of 643 men with coronary heart disease and 1278 controls nested in a prospective sutdy of 5661 men who were monitored for 16 years. We also did a meta-analysis of previous relevant studies to place our findings in context. RESULTS: Concentrations of soluble adhesion molecules were significantly associated with one another, with other markers of inflammation, and with some classic coronary risk factors. For ICAM-1, the odds ratio for CHD was 1.68 (95% CI 1.32-2.14) in a comparison of men in the top third with those in the bottom third of baseline measurements after adjustments for age and town. This decreased to 1.11 (0.75-1.64) after adjustment for some classic coronary risk factors and indicators of socioeconomic status. For the three other cell adhesion molecules, the odds ratios for CHD, first adjusted for age and town only, and then additionally adjusted for other risk factors, were: VCAM-1: 1.26 (0.99-1.61) and 0.96 (0.66-1.40); E-selectin: 1.27 (1.00-1.61) and 1.13 (0.78-1.62); and P-selectin: 1.23 (0.96-1.56) and 1.20 (0.81-1.76). INTERPRETATION: The measurement of these adhesion molecules is unlikely to add much predictive information to that provided by more established risk factors.

Adult↗
PubMed2001

A prospective study of Helicobacter pylori seropositivity and the risk for future myocardial infarction among socioeconomically similar U.S. men.

BACKGROUND: The role of Helicobacter pylori as a determinant of cardiovascular disease is controversial. OBJECTIVE: To determine whether previous exposure to H. pylori is associated with an increased risk for myocardial infarction. DESIGN: Prospective case-control study. SETTING: Physicians' Health Study. PARTICIPANTS: Initially healthy U.S. men. MEASUREMENTS: Titers of IgG antibody against H. pylori and several inflammatory markers were measured in baseline blood samples obtained from 445 men who subsequently had a myocardial infarction (case-patients) and 445 men matched for age and smoking status who remained free of vascular disease (controls) during a mean follow-up of 8.9 years. RESULTS: Baseline seropositivity was similar among case-patients and controls (43.4% vs. 44.3%; rate ratio, 0.96 [95% CI, 0.7 to 1.3]). Minimal evidence of association was found between magnitude of seropositivity and subsequent risk and between seropositivity and levels of the inflammatory biomarkers. CONCLUSION: In a socioeconomically homogeneous population, we found limited evidence of association between H. pylori exposure and risk for future myocardial infarction.

Biomarkers↗
PubMed2001

Fibrin D-dimer and coronary heart disease: prospective study and meta-analysis.

BACKGROUND: It is unknown whether modest increases of fibrin D-dimer, a circulating marker of fibrin turnover, are relevant to coronary heart disease (CHD) in the general population. METHODS AND RESULTS: We measured serum concentrations of D-dimer antigen in the stored baseline blood samples of 630 CHD cases and 1269 controls "nested" in a prospective cohort of 5661 men who were monitored for 16 years, and we conducted a meta-analysis of previous relevant studies to place our findings in context. In a comparison of men in the top third compared with those in the bottom third of baseline fibrin D-dimer values (tertile cutoffs, >94 versus <49 ng/mL), the odds ratio for CHD was 1.67 (95% CI, 1.31 to 2.13; P<0.0001) after adjustments for age and town. The odds ratio increased slightly after further adjustment for smoking, other classic risk factors, and indicators of socioeconomic status (1.79; 95% CI, 1.36 to 2.36). Strong correlations were observed of fibrin D-dimer values with circulating concentrations of C-reactive protein and serum amyloid A protein but not with smoking, blood lipids, blood pressure, and other risk factors. CONCLUSION: Although there may be an association between circulating D-dimer values and CHD, further studies are needed to determine the extent to which this is causal.

Adult↗
PubMed2000

Lipoprotein(a) and coronary heart disease. Meta-analysis of prospective studies.

BACKGROUND: -Studies of the association between the plasma concentration of lipoprotein(a) [Lp(a)] and coronary heart disease (CHD) have reported apparently conflicting findings. We report a meta-analysis of the prospective studies with at least 1 year of follow-up published before 2000. METHODS AND RESULTS: The following information was abstracted for each study: geographical location of study, size, type of cohort (population-based or selected because of previous disease), mean age, follow-up duration, blood storage temperature and duration, assay methods, degree of adjustment for potential confounders, and relationship of baseline Lp(a) measurement with subsequent CHD risk. There were 5436 deaths from CHD or nonfatal myocardial infarctions during a weighted mean follow-up of 10 years in the 27 eligible studies. Comparison of individuals in the top third of baseline plasma Lp(a) measurements with those in the bottom third in each study yielded a combined risk ratio of 1.6 (95% CI 1.4 to 1.8, 2P:<0.00001), with similar findings when the analyses were restricted to the 18 studies of general populations (combined risk ratio 1.7, 95% CI 1.4 to 1.9; 2P:<0. 00001). Despite differences among studies in blood storage techniques and assay methods, there was no significant heterogeneity among the results from the 18 population-based studies or among those from the 9 studies of patients with previous disease. Lp(a) was only weakly correlated with classical vascular risk factors, and adjustment for those that had been recorded made little difference to the reported risk ratios. CONCLUSIONS: These prospective studies demonstrate a clear association between Lp(a) and CHD, but further studies are needed to determine the extent to which this is causal.

Aged↗
PubMed2000

Low grade inflammation and coronary heart disease: prospective study and updated meta-analyses.

OBJECTIVE: To assess associations between baseline values of four different circulating markers of inflammation and future risk of coronary heart disease, potential triggers of systemic inflammation (such as persistent infection), and other markers of inflammation. DESIGN: Nested case-control comparisons in a prospective, population based cohort. SETTING: General practices in 18 towns in Britain. PARTICIPANTS: 506 men who died from coronary heart disease or had a non-fatal myocardial infarction and 1025 men who remained free of such disease until 1996 selected from 5661 men aged 40-59 years who provided blood samples in 1978-1980. MAIN OUTCOME MEASURES: Plasma concentrations of C reactive protein, serum amyloid A protein, and serum albumin and leucocyte count. Information on fatal and non-fatal coronary heart disease was obtained from medical records and death certificates. RESULTS: Compared with men in the bottom third of baseline measurements of C reactive protein, men in the top third had an odds ratio for coronary heart disease of 2.13 (95% confidence interval 1.38 to 3.28) after age, town, smoking, vascular risk factors, and indicators of socioeconomic status were adjusted for. Similar adjusted odds ratios were 1.65 (1.07 to 2.55) for serum amyloid A protein; 1.12 (0.71 to 1.77) for leucocyte count; and 0.67 (0.43 to 1.04) for albumin. No strong associations were observed of these factors with Helicobacter pylori seropositivity, Chlamydia pneumoniae IgG titres, or plasma total homocysteine concentrations. Baseline values of the acute phase reactants were significantly associated with one another (P<0.0001), although the association between low serum albumin concentration and leucocyte count was weaker (P=0.08). CONCLUSION: In the context of results from other relevant studies these findings suggest that some inflammatory processes, unrelated to the chronic infections studied here, are likely to be involved in coronary heart disease.

Acute-Phase Reaction↗
PubMed2000

Chlamydia pneumoniae IgG titres and coronary heart disease: prospective study and meta-analysis.

OBJECTIVE: To examine the association between coronary heart disease and serum markers of chronic Chlamydia pneumoniae infection. DESIGN: "Nested" case-control analysis in a prospective cohort study and an updated meta-analysis of previous relevant studies. SETTING: General practices in 18 towns in Britain. PARTICIPANTS: Of the 5661 men aged 40-59 who provided blood samples during 1978-80, 496 men who died from coronary heart disease or had non-fatal myocardial infarction and 989 men who had not developed coronary heart disease by 1996 were included. MAIN OUTCOME MEASURES: IgG serum antibodies to C pneumoniae in baseline samples; details of fatal and non-fatal coronary heart disease from medical records and death certificates. RESULTS: 200 (40%) of the 496 men with coronary heart disease were in the top third of C pneumoniae titres compared with 329 (33%) of the 989 controls. The corresponding odds ratio for coronary heart disease was 1.66 (95% confidence interval 1.25 to 2.21), which fell to 1.22 (0.82 to 1.82) after adjustment for smoking and indicators of socioeconomic status. No strong associations were observed between C pneumoniae IgG titres and blood lipid concentrations, blood pressure, or plasma homocysteine concentration. In aggregate, the present study and 14 other prospective studies of C pneumoniae IgG titres included 3169 cases, yielding a combined odds ratio of 1. 15 (0.97 to 1.36), with no significant heterogeneity among the separate studies (chi(2)=10.5, df=14; P>0.1). CONCLUSION: This study, together with a meta-analysis of previous prospective studies, reliably excludes the existence of any strong association between C pneumoniae IgG titres and incident coronary heart disease. Further studies are required, however, to confirm or refute any modest association that may exist, particularly at younger ages.

Adult↗
PubMed2000

Systematic review of the epidemiological evidence on Helicobacter pylori infection and nonulcer or uninvestigated dyspepsia.

BACKGROUND: Previous studies have yielded conflicting results and substantial uncertainty about any independent association of Helicobacter pylori infection with dyspepsia, and about any benefits of antibiotic treatments for nonulcer or uninvestigated dyspepsia. OBJECTIVES: To perform a systematic review of the literature to determine whether chronic infection with H pylori is relevant to nonulcer or uninvestigated dyspepsia. METHODS: Observational studies of associations between H pylori and dyspepsia published before April 1999 and randomized trials of the effects of H pylori eradication on dyspepsia published before January 2000 were identified by computer-assisted literature searches of relevant journals, reference lists, and discussions with authors. Relevant data were abstracted from the published reports by 2 investigators according to a fixed protocol. RESULTS: Thirty relevant observational studies were identified involving approximately 3392 patients with nonulcer dyspepsia, and 11 separate observational studies were identified, involving 6426 patients with uninvestigated dyspepsia. Reports of strong associations in small observational studies without appropriate adjustment for potential confounding factors were not generally confirmed by larger and better-designed studies. No studies have been reported, however, that can reliably confirm or exclude the existence of any weak associations. Twenty-two randomized trials of treatments against H pylori were found involving a total of 2340 patients with nonulcer dyspepsia, almost all with positive H pylori test results. Only a few of these trials involved effective antibacterial regimens with prolonged follow-up, and even these studies were too small to assess the possibility of moderate benefits. CONCLUSION: The available evidence indicates that there is no strong association between H pylori and dyspepsia, but there is insufficient evidence to confirm or refute the existence of a modest association.

Chronic Disease↗
PubMed2000

Prospective study of potentially virulent strains of Helicobacter pylori and coronary heart disease in middle-aged men.

BACKGROUND: Studies are needed to test claims that potentially virulent strains of Helicobacter pylori are more strongly related to coronary heart disease (CHD) than are other strains. METHODS AND RESULTS: We measured serum IgG antibodies to mixed H pylori antigens and separately to the virulence-associated H pylori antigen CagA (cytotoxin-associated gene product A) in 505 CHD cases and in 1025 age-matched controls "nested" in a prospective study of 7735 British men (mean duration of follow-up in controls, 16 years). Of the 505 cases, 401 (79%) were seropositive for H pylori antibodies compared with 740 (72%) of the 1025 controls, yielding an odds ratio for CHD of 1.55 (95% CI 1.19 to 2.03), which fell to 1.30 (95% CI 0.88 to 1. 90) after adjustments were made for standard vascular risk factors and indicators of socioeconomic status. Of the CHD cases, 240 (48%) were seropositive for IgG antibodies to CagA compared with 450 (44%) of the controls. When CagA-seropositive individuals were compared with H pylori-seronegative individuals, the odds ratio for CHD was 1. 42 (95% CI 1.06 to 1.91), which fell to 1.10 (95% CI 0.71 to 1.71) after adjustments. In an analysis restricted to the 1141 (75%) H pylori-seropositive participants, the odds ratio for CHD was 1.0 (95% CI 0.78 to 1.29) in CagA-seropositive men. No strong associations were observed between H pylori seropositivity and blood lipids, blood pressure, markers of systemic inflammation, or plasma homocysteine. CONCLUSIONS: H pylori infection is not strongly related to the incidence of CHD in late middle-aged men, and CagA-positive strains appear to be no more strongly related to the disease than other strains. However, further studies are required to confirm or refute the existence of any moderate associations, particularly at younger ages.

Antibodies, Bacterial↗
PubMed2000

High prevalence of potentially virulent strains of Helicobacter pylori in the general male British population.

BACKGROUND: Strains of Helicobacter pylori that express the cytotoxin associated gene product A (CagA) may be more strongly associated with serious gastric diseases, such as gastric cancer and peptic ulceration, than other strains. Data, however, are sparse on the prevalence, risk factors, and other correlates of these strains in the general population. AIM: To characterise aspects of the seroepidemiology of CagA(+) strains of H pylori in the general British population. METHODS: We measured serum IgG antibodies to mixed H pylori antigens and separately to CagA in 1025 men aged 40-59 years who were randomly selected from a larger group of participants in a community based survey conducted in 18 different British towns. RESULTS: Overall, 44% (95% confidence interval 41-47%) of the men were seropositive to CagA antibodies, representing about 61% (57-65%) of the men seropositive to mixed antigen H pylori. The risk factors for seropositivity to CagA antibodies were similar to those for seropositivity to mixed antigen H pylori, apart from an increased prevalence of reported bedroom sharing in childhood (p<0.01). CONCLUSION: In a nationwide study of potentially virulent H pylori strains, there was a high prevalence of the infection, with some evidence that acquisition of such strains might occur earlier in life than other strains.

Aged↗