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G De Backer

Publications and source records attributed to G De Backer.

At least 37 records · Page 2Linked to original sources
PubMed2002

Parameters of inflammation and infection in a community based case-control study of coronary heart disease.

BACKGROUND: increased levels of systemic inflammatory markers appear to be related to coronary heart disease (CHD) both in asymptomatic individuals and in subjects with established CHD. Whether these associations are related to confounding coronary risk factors or are explicable through chronic infectious conditions is not clear. OBJECTIVES: (1) to determine whether subjects with stable CHD differ from normal controls in inflammatory markers (CRP, SAA and fibrinogen) and/or in serostatus of four infectious agents (Helicobacter pylori, Chlamydia pneumoniae, CMV and EBV), independent of classical coronary risk factors. (2) To determine whether these inflammatory markers are related to the serostatus against these four infectious agents either in patients with CHD or in normal subjects. METHODS: in a large epidemiologic survey, 446 out of 16307 men at work, aged 35-59 years, had antecedents of myocardial infarction, CABG or PTCA or had prominent Q/QS waves on their resting ECG. They were compared with double the number (n=892) of men, matched for age, educational level and industry. Inflammatory biomarkers (CRP, fibrinogen and SAA) and antibodies against H. pylori, C. pneumoniae, CMV and EBV were measured, besides classical coronary risk factors. RESULTS: in univariate analyses, cases had higher CRP, fibrinogen and SAA levels than controls, but no differences were observed in serumantibody levels to any of the infectious agents. Markers of previous infections were not related to inflammatory biomarkers. In multivariate analyses CRP was significantly different between cases and controls independent of differences in other coronary risk factors and in the use of lipid lowering drugs and antiplatelet aggregants. CONCLUSIONS: in men at work with CHD, CRP levels are significantly different from controls, independent of known risk factors. No association was found between inflammatory biomarkers and positive serostatus against four infectious agents, neither in the patients nor in the healthy controls.

Acute-Phase Proteins↗
PubMed2002

Job conditions and fibrinogen in 14226 Belgian workers: the Belstress study.

AIMS: To investigate the relationship between fibrinogen and stressful work conditions, where perceived strain is defined by the simultaneous presence of high psychological demands and low control, according to Karasek's Demand/Control/(Social Support) model. METHODS AND RESULTS: A cross-sectional study was realized between 1994 and 1998 in 24 Belgian enterprises, on 16335 male and 5084 female middle-aged workers of different Belgian companies participating in the Belstress study. This study confirmed the well-documented bivariate relationship between plasma fibrinogen levels and gender, age, educational level, smoking, obesity, physical activity, alcohol consumption, total cholesterol, HDL-cholesterol, arterial hypertension and diabetes. No independent multivariate relationship was observed between job control, psychological job demands or social support at work and plasma fibrinogen, but after stratification a positive association (P< or =0.05) was observed between psychological job demands and plasma fibrinogen for males in the lowest educational level. Moreover a positive statistically significant association between job strain and plasma fibrinogen was observed in males but not in females. After stratification for educational level this association remained significant for males especially in the lowest educational level (P< or =0.001) and became significant for females in the middle educational level. CONCLUSIONS; As suggested in our study and others, plasma fibrinogen could be one of the potential mediators explaining the relationship between job stress and coronary heart disease.

Adult↗
PubMed2002

Maternal and umbilical fatty acid status in relation to maternal diet.

The aim of this study was to describe the dietary fat intake during pregnancy and to study the relationship between the intake of polyunsaturated fatty acids (PUFAs) and the fatty acid composition of maternal and umbilical plasma phospholipids (PLs) and cholesterol esters (CEs) at delivery. In addition, the contribution of food groups to the intake of total fat and fatty acids in the diet was quantified.Maternal and umbilical blood samples were collected at delivery from 30 healthy pregnant women. The women completed a food frequency questionnaire during the first and third trimesters. The total fat intake during pregnancy is 85 (SD 24) g/day. The mean intake of saturated fatty acids (SFAs) is 33.4 g/day, of monounsaturated fatty acids (MUFAs) 28.6 g/day and of PUFA 15.2 g/day. Major sources of fat, MUFA and PUFA are fats, oils and sauces. Major sources of SFA are meat and poultry followed by cheese and eggs. Meat and poultry contribute the most to the intake of 20:4n-6 whereas fish is the major source of 20:5n-3 (EPA) and 22:6n-3 (docosahexaenoic acid (DHA)) in the diet. Linoleic acid, EPA and DHA (w%) in PL of maternal plasma are positively related to the intake of these fatty acids during pregnancy. No association is found between the maternal intake of the two parent essential fatty acids (18:2n-6 and 18:3n-3) and their fraction in umbilical PL or CE. EPA and the sum of n-6 fatty acids (w%) in umbilical plasma PL are positively correlated with the dietary intake of these fatty acids.

Animals↗
PubMed2002

Probabilistic intake assessment and body burden estimation of dioxin-like substances in background conditions and during a short food contamination episode.

The objective was to perform a dioxin body burden estimate based on a probabilistic intake assessment of PCDDs, PCDFs and dioxin-like PCBs because of the so-called 1999 'Belgian dioxin incident'. Monte Carlo simulation techniques were used to combine detailed 7-day food intake data on the individual level from a sample of 14-18-year-old adolescents with 'background' and 'incident-related' food contamination data. In background conditions, 3% of the adolescents had an intake <1 pg TEQ kg(-1) bw day(-1), while 85% had <4 pg TEQ kg(-1) bw day(-1). Milk and other dairy products were the basic source of dioxin-like contaminants, while fish constituted the main source at the higher percentiles of intake. During the dioxin incident, the estimated median dioxin intake showed a moderate increase. At the 99th percentile, the highest intake level, and the 95% upper bound uncertainty level, peak body burden-23.73 ng TEQ kg(-1) bw-remained below body burdens that in the experimental animal or in man are accompanied by a population-based observable increase in the incidence of adverse effects. The 1999 Belgian dioxin incident most likely did not affect public health in Belgium in a measurable way, although exceptions remain possible on the individual level.

Adolescent↗
PubMed2002

Age-specific accuracy of initial versus subsequent mammography screening: results from the Ghent breast cancer-screening programme.

The aim of this study was to determine whether age-related differences in the accuracy of mammography breast cancer screening decrease with repeated examination. Data from the first 8 years (May 1992 to April 1999) of the Ghent breast cancer-screening programme were used for analysis. In total, 28 944 mammography examinations were included. The referral rate, cancer detection rate, positive predictive value, sensitivity and specificity were chosen as performance indicators. Values were calculated for women aged 40-49, 50-59 and 60-69 years, at initial versus subsequent examinations, respectively. For first examinations, overall, performance was much lower for the women in their forties than for the older age groups. On subsequent screening, the effect of age disappeared, as expected, or was even reversed for the positive predictive value and sensitivity of the examination. In the light of the ongoing debate over the eligible age for mammography screening, these results support a universal recommendation beginning at the age of 40 years.

Adult↗
PubMed2001

Age- and gender-specific differences in left ventricular cardiac function and volumes determined by gated SPET.

The aim of this study was to determine normative volumetric data and ejection fraction values derived from gated myocardial single-photon emission tomography (SPET) using the commercially available software algorithm QGS (quantitative gated SPET). From a prospective database of 876 consecutive patients who were referred for a 2-day stress-rest technetium-99m tetrofosmin (925 MBq) gated SPET study, 102 patients (43 men, 59 women) with a low (<10%) pre-test likelihood of coronary disease were included (mean age 57.6 years). For stress imaging, a bicycle protocol was used in 79 of the patients and a dipyridamole protocol in 23. Left ventricular ejection fraction (LVEF) and end-diastolic and -systolic volumes (EDV and ESV) were calculated by QGS. EDV and ESV were corrected for body surface area, indicated by EDVi and ESVi. To allow comparison with previous reports using other imaging modalities, men and women were divided into three age groups (<45 years, > or =45 years but <65 years and > or =65 years). Men showed significantly higher EDVi and ESVi values throughout and lower LVEF values when compared with women in the subgroup > or =65 years (P<0.05, ANOVA). Significant negative and positive correlations were found between age and EDVi and ESVi values for both women and men and between LVEF and age in women (Pearson P< or =0.01). LVEF values at bicycle stress were significantly higher than at rest (P=0.000, paired t test), which was the result of a significant decrease in ESV (P=0.003), a phenomenon which did not occur following dipyridamole stress (P=0.409). The data presented suggest that LVEF and EDVi and ESVi as assessed by QGS are strongly gender-specific. Although the physiological significance of these results is uncertain and needs further study, these findings demonstrate that the evaluation of cardiac function and volumes of patients by means of QGS should consider age- and gender-matched normative values.

Adult↗
PubMed2001

Haptoglobin polymorphism as a risk factor for coronary heart disease mortality.

OBJECTIVES: the aim of our study was to evaluate the independent role of the haptoglobin (Hp) polymorphism as a risk factor for coronary heart disease (CHD) mortality. METHODS: within the framework of the longitudinal part of the Belgian Interuniversity Research on Nutrition and Health (BIRNH) survey, a nested case-control study design was performed through matching the 107 deaths from CHD, occurring within a 10-year follow-up period, with three controls for age and gender. RESULTS: the distribution of the Hp types was found to be in Hardy-Weinberg equilibrium. Conditional logistic regression analysis for matched sets revealed that the Hp polymorphism was significantly associated with CHD death. Rather surprisingly, the finding was that Hp 1-1 individuals were at doubled risk for CHD mortality compared with the others, the odds ratio being 2.09 (95% CI: 1.22-3.60). The association was independent from other classical cardiovascular risk factors and the Hp concentration, and of comparable magnitude between men and women. Moreover, evaluating the interaction term in a multiplicative model showed that the Hp type did not play a synergistic role in the prognostic value of established cardiovascular risk factors. CONCLUSION: in contrast to the findings from cross-sectionally based studies, the results from this longitudinal study show that Hp 1-1 individuals are at elevated risk for CHD mortality.

Aged↗
PubMed2001

Fibrinogen and C-reactive protein on admission as markers of final infarct size after primary angioplasty for acute myocardial infarction.

BACKGROUND: In acute myocardial infarction (AMI) treated conservatively or with thrombolysis, marked increases of C-reactive protein (CRP) and fibrinogen have been observed. No data are however available concerning a possible relation between CRP and fibrinogen levels on admission and markers of infarct size after obtaining thrombolysis in myocardial infarction (TIMI) flow III by primary angioplasty. METHODS: We studied 34 patients with a first AMI (29 men, mean age 54+/-11 years) who were treated with primary angioplasty (TIMI flow III in all patients, no concomitant treatment with glycoprotein IIb-IIIa antagonists) within 6 h of onset of pain. CRP and fibrinogen levels on admission were determined and related to the following markers of infarct size: peak creatine kinase MB (CKMB) levels, radionuclide left ventricular ejection fraction (LVEF) at discharge and thallium-201 single-photon emission computed tomography (SPECT) infarct size at 1 month. RESULTS: Median CRP levels were 0.4 mg/dl (range 0.09-3 mg/dl), median fibrinogen levels 412 mg/dl (range 198-679 mg/dl), mean CKMB was 178+/-151 U/l, mean LVEF 52+/-8% and mean thallium-201 infarct size 7+/-6%. Although CRP levels were related to fibrinogen levels on admission (r=0.56, P=0.002), only fibrinogen levels were related to markers of infarct size (r=0.58, P=0.001 for CKMB, r=-0.44, P=0.01 for LVEF and r=0.64, P=0.001 for thallium-201 infarct size). No relation was found between CRP or fibrinogen levels on admission and the extent of coronary artery disease or the myocardial area at risk. In multiple regression analysis, the relation between fibrinogen and markers of infarct size was independent of CRP levels and the duration of pain on admission. CONCLUSIONS: These findings indicate a relation between fibrinogen levels on admission and myocardial infarct size in patients treated with primary angioplasty for AMI. This relation seems to be independent of CRP levels and the duration of pain on admission. If confirmed in larger patient populations, fibrinogen levels on admission could have an important value for risk stratification and more aggressive reduction of infarct size in patients who are treated with primary angioplasty.

Acute Disease↗
PubMed2001

ACC/AHA/ESC guidelines for the management of patients with atrial fibrillation: executive summary. A Report of the American College of Cardiology/ American Heart Association Task Force on Practice Guidelines and the European Society of Cardiology Committee for Practice Guidelines and Policy Conferences (Committee to Develop Guidelines for the Management of Patients With Atrial Fibrillation): developed in Collaboration With the North American Society of Pacing and Electrophysiology.

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Algorithms↗
PubMed2001

Psychological status and the role of coping style after coronary artery bypass graft surgery. Results of a prospective study.

The results of a prospective study in patients who underwent a first coronary artery bypass graft operation are presented. The goals of this project consisted in assessing the psychological changes during the first year after surgery. For that purpose, 330 consecutive patients were recruited. They were assessed by means of several psychological scales before and on three occasions after surgery. These scales were: the Heart Patients' Psychological Questionnaire (HPPQ), the State-Trait Anxiety Scale (STAI), the Symptom Check List (SCL-90), the Maastricht Questionnaire (MQ) and the Marlowe Crowne Desirability Scale. Furthermore, the study focused on the differential influence of three coping styles. The data demonstrate a clear overall improvement in psychological status over the first year, more specifically during the first 6 months after CABG. Patients were less anxious, less depressed, less exhausted and experienced more subjective well-being. However, almost 30% of all patients did not experience that average favourable evolution. The final psychological end-state was predicted by psychological variables, measured pre-operatively (somatic complaints, hostility and dysphoria) and short-term post-operatively (anxiety). No single medical variable could predict patients' psychological end-state. Finally, the most favourable change was made by patients who display the sensitising coping style, resulting in lower anxiety and depression. Health care providers, physicians as well as nursing staff and psychologists, should therefore use psychodiagnostic tools in order to identify patients at risk for negative psychological outcome. Appropriate therapeutic interventions may consequently be developed and evaluated in future research.

Adaptation, Psychological↗
PubMed2001

Estimation of dietary fat intake of Belgian pregnant women. Comparison of two methods.

AIM: To evaluate the validity and usefulness of a food frequency questionnaire (FFQ) which was designed to evaluate individual fat consumption for a Dutch population relative to 7-day estimated records (7d ER). The FFQ has been validated previously and was adapted to the Belgian situation. METHODS: Longitudinal study in 26 healthy pregnant women; FFQ and 7d ER were obtained during the 1st and 3rd trimesters. RESULTS: FFQ was validated with 7d ER. Fat and fatty acid intake estimated by the FFQ did not differ significantly (p < 0.01) from data obtained by the 7d ER except for 18:2n-6. Pearson correlation coefficient between the 2 methods ranged from 0.62 to 0.68. On average, 47% of the women were classified in the same quartile with the 2 methods and less than 2% in the opposite quartile. Total fat intake, calculated from FFQ, was on average 87.9 (SD 18.1) g/day. The mean intake of linoleic acid was 13.3 (SD 5.4) g/day and of alpha-linolenic acid was 1.4 (SD 0.5) g/day. The dietary intake of the saturated, monounsaturated and polyunsaturated fatty acids was respectively 34.7 (SD 10.0) g/day, 29.6 (SD 8.1) g/day and 15.7 (SD 5.9) g/day. CONCLUSION: The FFQ gives similar results for fat intake as the 7d ER and is thus considered an appropriate method for classifying individuals to the right part of the distribution of dietary fat intake.

Adult↗
PubMed2001

The efficacy of atorvastatin in treating patients with hypercholesterolaemia to target LDL-cholesterol goals: the LIPI-GOAL trial.

OBJECTIVE: LIPI-GOAL is a multicentre, open-label, non-comparative treat-to-target study, conducted from March 1998 to May 1999, that assessed the percentage of patients reaching 1992 European Atherosclerosis Society (EAS) low-density lipoprotein cholesterol (LDL-C) targets with atorvastatin 10-80 mg/day in subjects with hypercholesterolaemia, defined as LDL-C > 160 mg/dl after a 12-week step I diet. METHODS AND RESULTS: Patients were treated towards the following LDL-C goals: < 135 mg/dl in patients with atherosclerotic disease present and/or coronary heart disease (CHD) risk >40%/10 years, or LDL-C < 155 mg/dl in all others. All subjects started treatment with atorvastatin 10 mg/day for 6 weeks. The dose was doubled every 6 weeks, to 20, 40, or 80 mg/day at weeks 12, 18, and 24, respectively, if targets were not reached. Of 587 patients screened for participation, 473 were enrolled and 419 (59% male; mean age 61 years) were available for efficacy evaluation. Fifty-five percent had atherosclerotic disease and/or CHD risk >40%/10 years. Dose titration was not needed in 303 patients (72%) who reached LDL-C target with atorvastatin 10 mg/day. Among 116 patients who were subsequently treated with higher atorvastatin dosages, 47 reached LDL-C target with 20 mg/day, 15 with 40 mg/day, and 6 with 80 mg/day. Therefore, 88.5% of subjects reached LDL-C goal in an intention-to-treat analysis. In general, atorvastatin was well tolerated. CONCLUSIONS: Most patients at high risk for CHD reached LDL-C goals with atorvastatin 10-80 mg/day. Seventy-two % of patients reached target with atorvastatin 10 mg/day, which may simplify clinical management and should encourage better adherence to recommendations.

Aged↗
PubMed2001

[Relation between uricemia and total, cardiovascular and coronary mortality in both genders of non-selected sample of the Belgium population].

BACKGROUND: Despite more than 40 years of research on the prognostic value of hyperuricemia in relation to all-causes cardiovascular and coronary mortality, no clear consensus appears in the medical literature. Moreover, the observed relationship between hyperuricemia and the incidence of coronary heart disease mortality is related to gender. However, prospective studies including both genders are rare. METHODS: A prospective study was conducted in a random sample of 5225 males and 4476 females from the Belgian population aged 25 to 74 years at the initial survey and followed for 10 years for all-causes and specific mortality. RESULTS: The number of observed total, cardiovascular, and coronary heart disease deaths were 648 and 239, 150 and 225, and 96 and 51 in males and females respectively. At multivariate analysis, uricemia was significantly correlated with all-causes mortality in males whereas a tendency was observed in females. The same diverging association was observed for cardiovascular mortality. However, for coronary heart disease mortality, there was a very significant correlation only in females. CONCLUSIONS: Our findings confirm the observed gender-related differences in the relation of hyperuricemia with all-causes and coronary heart disease mortality. We propose possible pathogenic mechanisms concerning the relationship with coronary heart disease mortality observed only in females.

Adult↗
PubMed2000

Automatic quantification of defect size using normal templates: a comparative clinical study of three commercially available algorithms.

Infarct size assessed by myocardial single-photon emission tomography (SPET) imaging is an important prognostic parameter after myocardial infarction (MI). We compared three commercially available automatic quantification algorithms that make use of normal templates for the evaluation of infarct extent and severity in a large population of patients with remote MI. We studied 100 consecutive patients (80 men, mean age 63 +/- 11 years, mean LVEF 47% +/- 15%) with a remote MI who underwent resting technetium-99m tetrofosmin gated SPET study for infarct extent and severity quantification. The quantification algorithms used for comparison were a short-axis algorithm (Cedars-Emory quantitative analysis software, CEqual), a vertical long-axis algorithm (VLAX) and a three-dimensional fitting algorithm (Perfit). Semiquantitative visual infarct extent and severity assessment using a 20-segment model with a 5-point score and the relation of infarct extent and severity with rest LVEF determined by quantitative gated SPET (QGS) were used as standards to compare the different algorithms. Mean infarct extent was similar for visual analysis (30% +/- 21%) and the VLAX algorithm (25% +/- 17%), but CEqual (15% +/- 11%) and Perfit (5% +/- 6%) mean infarct extents were significantly lower compared with visual analysis and the VLAX algorithm. Moreover, infarct extent determined by Perfit was significantly lower than infarct extent determined by CEqual. Correlations between automatic and visual infarct extent and severity evaluations were moderate (r = 0.47, P < 0.0001 to r = 0.62, P < 0.0001) but comparable for all three algorithms. Correlations between LVEF and visual evaluation of infarct extent (r = -0.80, P < 0.0001) and severity (r = -0.82, P < 0.0001) were good but correlations were significantly lower for all three algorithms (r = -0.48, P < 0.0001 to r = -0.65, P < 0.0001). Systematically lower correlations were found in non-anterior infarctions (n = 69) and obese patients (BMI > or = 30 kg/m2, n = 32) compared with anterior infarctions and non-obese patients for all three algorithms. In this large series of post-MI patients, results of infarct extent and severity determination by automatic quantification algorithms that make use of normal templates were not interchangeable and correlated only moderately with semiquantitative visual analysis and LVEF.

Adult↗
PubMed2000

Potential for cholesterol lowering in secondary prevention of coronary heart disease in europe: findings from EUROASPIRE study. European Action on Secondary Prevention through Intervention to Reduce Events.

We have examined the potential for cholesterol lowering in secondary prevention of coronary heart disease based on data from the European Action on Secondary Prevention through Intervention to Reduce Events (EUROASPIRE) study carried out in 1995-1996 in nine European centres (Czech Republic, Finland, France, Germany, Hungary, Italy, The Netherlands, Slovenia and Spain). Consecutive patients aged < or = 70 years in four diagnostic categories--coronary artery bypass grafting, percutaneous transluminal coronary angioplasty, acute myocardial infarction, and acute myocardial ischaemia without infarction--were identified from hospital records and invited for an interview and risk factor assessment at least 6 months after hospital admission. Plasma lipid measurements were carried out in a central laboratory. Combining patients from all centres and diagnostic categories (n = 2749) the medians (interquartile ranges) for plasma lipids were: total cholesterol 5.36 (4.76-6.03) mmol/l, high density lipoprotein (HDL) cholesterol 1.19 (1.01-1.42) mmol/l, triglycerides 1.55 (1.15-2.24) mmol/l, and low density lipoprotein (LDL) cholesterol 3.32 (2.76-3.91) mmol/l. Only 33% of the patients received lipid-lowering drugs. If the therapeutic goal given in the 1998 European recommendations, total cholesterol < 5.0 mmol/l, were applied, 67% of these patients would have needed an intensified cholesterol-lowering action, and with an even stricter goal, total cholesterol < 4.5 mmol/l, this proportion would have been as high as 84%.

Aged↗
PubMed2000

Apolipoprotein E serum concentration and polymorphism in six European countries: the ApoEurope Project.

As part of the ApoEurope Project, the apolipoprotein E (apo E) serum concentration and polymorphism were determined in 6934 healthy subjects aged 25-64 years recruited in six European countries: Finland; France; Greece; Northern Ireland; Portugal and Spain. Age and sex influenced apo E concentration with concentrations being significantly higher in men than in women for those aged between 25 and 44 years. The age effect differed between the sexes after the age of 44 years, displaying a linear increase in women and a plateau in men. As expected, the serum apo E concentration was highest in varepsilon2 carriers and lowest in varepsilon4 carriers in each country with a significantly higher frequency of the varepsilon4 allele in the northern regions. The main finding of this study was a clear increasing North-South gradient in serum apo E concentration independent of age, sex and apo E genotype. In subjects aged <45 years and with the varepsilon3/varepsilon3 genotype, apo E concentration was higher in the South-East (Greece) as compared to the North by 20% for men and 32% for women. In addition to the genetic polymorphism, the geographical area is an important factor to take into account when studying serum apo E concentration in multicentre studies and defining reference values.

Adult↗