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Featured researches published by Jan Broer.


European Journal of Clinical Nutrition | 2004

Increased alpha-linolenic acid intake lowers C-reactive protein, but has no effect on markers of atherosclerosis

Wje Bemelmans; Joop D. Lefrandt; E.J.M. Feskens; P.L. van Haelst; Jan Broer; B Meyboom-de Jong; Jf May; Jan W. Cohen Tervaert; Andries J. Smit

Objective: To investigate the effects of increased alpha-linolenic acid (ALA)-intake on intima–media thickness (IMT), oxidized low-density lipoprotein (LDL) antibodies, soluble intercellular adhesion molecule-1 (sICAM-1), C-reactive protein (CRP), and interleukins 6 and 10.Design: Randomized double-blind placebo-controlled trial.Subjects: Moderately hypercholesterolaemic men and women (55±10 y) with two other cardiovascular risk factors (n=103).Intervention: Participants were assigned to a margarine enriched with ALA (fatty acid composition 46% LA, 15% ALA) or linoleic acid (LA) (58% LA, 0.3% ALA) for 2 y.Results: Dietary ALA intake was 2.3 en% among ALA users, and 0.4 en% among LA users. The 2-y progression rate of the mean carotid IMT (ALA and LA: +0.05 mm) and femoral IMT (ALA:+0.05 mm; LA:+0.04 mm) was similar, when adjusted for confounding variables. After 1 and 2 y, ALA users had a lower CRP level than LA users (net differences −0.53 and −0.56 mg/l, respectively, P<0.05). No significant effects were observed in oxidized LDL antibodies, and levels of sICAM-1, interleukins 6 and 10.Conclusions: A six-fold increased ALA intake lowers CRP, when compared to a control diet high in LA. The present study found no effects on markers for atherosclerosis.Sponsorship: The Dutch ‘Praeventiefonds’.


American Journal of Preventive Medicine | 2009

Preventing Weight Gain : One-Year Results of a Randomized Lifestyle Intervention

Nancy C. W. ter Bogt; Wanda J. E. Bemelmans; Frank W. Beltman; Jan Broer; Andries J. Smit; Klaas van der Meer

BACKGROUND Lifestyle interventions targeting prevention of weight gain may have better long-term success than when aimed at weight loss. Limited evidence exists about such an approach in the primary care setting. DESIGN An RTC was conducted. SETTING/PARTICIPANTS Participants were 457 overweight or obese patients (BMI=25-40 kg/m(2), mean age 56 years, 52% women) with either hypertension or dyslipidemia, or both, from 11 general practice locations in The Netherlands. INTERVENTION In the intervention group, four individual visits to a nurse practitioner (NP) and one feedback session by telephone were scheduled for lifestyle counseling with guidance of the NP using a standardized computerized software program. The control group received usual care from their general practitioner (GP). MAIN OUTCOME MEASURES Changes in body weight, waist circumference, blood pressure, and blood lipids after 1 year (dropout <10%). Data were collected in 2006 and 2007. Statistical analyses were conducted in 2007 and 2008. RESULTS There were more weight losers and stabilizers in the NP group than in the general practitioner usual care (GP-UC) group (77% vs 65%; p<0.05). In men, mean weight losses were 2.3% for the NP group and 0.1% for the GP-UC group (p<0.05). Significant reductions occurred also in waist circumference but not in blood pressure, blood lipids, and fasting glucose. In women, mean weight losses were in both groups 1.6%. In the NP group, obese people lost more weight (-3.0%) than the non-obese (-1.3%; p<0.05). CONCLUSIONS Standardized computer-guided counseling by NPs may be an effective strategy to support weight-gain prevention and weight loss in primary care, in the current trial, particularly among men. TRIAL REGISTRATION The study was registered with the Netherlands Trial Register (NTR), www.trialregister.nl, study no. TC 1365.


Public Health Nutrition | 2000

Impact of Mediterranean diet education versus posted leaflet on dietary habits and serum cholesterol in a high risk population for cardiovascular disease

Wanda J. E. Bemelmans; Jan Broer; Jeanne H.M. de Vries; K.F.A.M. Hulshof; Jo F. May; Betty Meyboom-de Jong

OBJECTIVE To investigate the impact of intensive group education on the Mediterranean diet on dietary intake and serum total cholesterol after 16 and 52 weeks, compared to a posted leaflet with the Dutch nutritional guidelines, in the context of primary prevention of cardiovascular disease (CVD). DESIGN Controlled comparison study of an intervention group given intensive group education about the Mediterranean diet and a control group of hypercholesterolaemic persons given usual care by general practitioners (GPs). SETTING A socioeconomically deprived area in the Netherlands with an elevated coronary heart disease (CHD) mortality ratio. SUBJECTS Two hundred and sixty-six hypercholesterolaemic persons with at least two other CVD risk factors. RESULTS After 52 weeks, the intervention group decreased total and saturated fat intake more than the control group (net differences were 1.8 en% (95%CI 0.2-3.4) and 1.1 en% (95%CI 0. 4-1.9), respectively). According to the Mediterranean diet guidelines the intake of fish, fruit, poultry and bread increased in the intervention group, more than in the control group. Within the intervention group, intake of fish (+100%), poultry (+28%) and bread (+6%) was significantly increased after 1 year (P < 0.05). The intensive programme on dietary education did not significantly lower serum cholesterol level more (-3%) than the posted leaflet (-2%) (net difference 0.06 mmol l-1, 95%CI -0.10 to 0.22). Initially, the body mass index (BMI) decreased more in the intervention group, but after 1 year the intervention and control group gained weight equally (+1%). CONCLUSIONS Despite beneficial changes in dietary habits in the intervention group compared with the control group, after 1 year BMI increased and total fat and saturated fat intake were still too high.


European Journal of Clinical Nutrition | 2000

Associations of alpha-linolenic acid and linoleic acid with risk factors for coronary heart disease

Wje Bemelmans; Frits A.J. Muskiet; E.J.M. Feskens; Jhm Vries; Jan Broer; Jf May; B Meyboom-de Jong

Background: Prevention of coronary heart disease (CHD) in high-risk subjects.Objective: To investigate the associations of dietary intake of alpha-linolenic acid (ALA) and linoleic acid (LA) as assessed by food frequency questionnaire and in the plasma cholesteryl ester (CE), with CHD risk factors.Design: Baseline data of a double-blind, randomized placebo-controlled trial. Subjects have hypercholesterolemia (6.0–8.0 mmol/l) and at least two other CHD risk factors (n=266).Results: The reported dietary ALA and LA intakes and the LA/ALA ratio were associated with the contents in the CE (r=0.37, r=0.21, and r=0.42, respectively; P<0.01). In multivariate analysis, CE ALA was inversely associated with diastolic blood pressure (r=−0.13; P<0.05) and positively with serum triacylglycerol (r=0.13; P<0.05), and CE LA was inversely associated with serum triacylglycerol (r=−0.32; P<0.01). The CE LA/ALA ratio was strongly inversely associated with CE ALA (r=−0.95; P<0.01). In the lowest quintile of CE ALA, mean dietary intake was 0.4 energy % ALA (1.2 g/day), 8.4 energy % LA and an LA/ALA ratio of 21, and in the highest quintile 0.6 energy % ALA (1.7 g/day), 6.8 energy % LA and 12 (ratio). In the lowest quintile of CE ALA the diastolic blood pressure was 4 mmHg lower (P trend<0.05), and the serum triacylglycerol 0.3 mmol/l higher (P trend NS) when compared with the top quintile.Conclusions: In a CHD high-risk population with LA-rich background diet, these cross-sectional data suggest that replacing LA in the diet by ALA may decrease diastolic blood pressure, and may increase serum triacylglycerol concentration.Sponsorship: Dutch Prevent fund grant no. 28-2757; Unilever (margarine).European Journal of Clinical Nutrition (2000) 54, 865–871


Atherosclerosis | 2002

Change in saturated fat intake is associated with progression of carotid and femoral intima-media thickness, and with levels of soluble intercellular adhesion molecule-1

Wanda J. E. Bemelmans; Johan Lefrandt; Edith J. M. Feskens; Jan Broer; Jan Willem Cohen Tervaert; Jf May; Andries J. Smit

BACKGROUND A high saturated fat (SFA) intake may stimulate progression of atherosclerosis, and may be positively associated with expression of adhesion molecules. METHODS In moderately hypercholesterolaemic participants of a dietary intervention study (n=103; 55+/-10 years), we examined associations between reported changes in SFA intake and changes in carotid and femoral intima-media thickness (IMT) and soluble intercellular adhesion molecule-1 (sICAM-1) levels after 2 years. The carotid and femoral IMT was assessed by high-resolution B-mode ultrasound images. RESULTS After 2 years, dietary intake of SFA decreased with 1.8+/-2.6% of energy (P<0.01). In the lowest quintile of change in SFA intake (-5.9+/-1.4% of energy), changes in carotid and femoral IMT were +0.03 mm (SEM 0.03) and -0.09 mm (SEM 0.07), respectively, versus +0.10 mm (SEM 0.03), +0.17 mm (SEM 0.07) in the top quintile (+1.6+/-0.7% of energy) (P linear trend 0.07 (carotis), 0.02 (femoralis)). Changes in sICAM-1 were -19.0 ng/nl (SEM 5.6) in the lowest quintile, versus +8.6 ng/ml (SEM 5.3) in the top quintile (P linear trend <0.001), adjusted for baseline level, SFA intake, body mass index, age, changes in intake of fruit, polyunsaturated fat, and dietary cholesterol. Adjustments for changes in established risk factors did not alter these results. CONCLUSIONS Decreased SFA intake may reduce progression of atherosclerosis, as assessed by IMT, and is associated with reduced levels of sICAM-1 after 2 years. Further research using randomised placebo-controlled trials is necessary to exclude potential confounding variables and to confirm causality.


JAMA Internal Medicine | 2011

Preventing weight gain by lifestyle intervention in a general practice setting - three-year results of a randomized controlled trial

Nancy C. W. ter Bogt; Wanda J. E. Bemelmans; Frank W. Beltman; Jan Broer; Andries J. Smit; Klaas van der Meer

BACKGROUND Weight regain after initial loss of weight is common, which indicates a need for lifestyle counseling aimed at preventing weight gain instead of weight loss. This study was conducted to determine whether structured lifestyle counseling by nurse practitioners (NPs) group compared with usual care by general practitioners (GP-UC) in overweight and obese patients can prevent (further) weight gain. METHODS A randomized controlled trial in 11 general practice locations in the Netherlands of 457 patients (body mass index, 25-40 [calculated as weight in kilograms divided by height in meters squared]; mean age, 56 years; 52% female) with either hypertension or dyslipidemia or both. The NP group received lifestyle counseling with guidance of the NP using a standardized software program. The GP-UC group received usual care from their GP. Main outcome measures were changes in body weight, waist circumference, blood pressure, and fasting glucose and blood lipid levels after 3 years. RESULTS In both groups, approximately 60% of the participants achieved weight maintenance after 3 years. There was no significant difference in mean (SD) weight change and change of waist circumference between the NP and GP-UC groups (weight change: NP group, -1.2% [5.8%], and GP-UC group, -0.6% [5.6%] [P = .37]; and change of waist circumference: NP group, -0.8 [7.1] cm, and GP-UC group, 0.4 [7.2] cm [P = .11]). A significant difference occurred for mean (SD) fasting glucose levels (NP group, -0.02 [0.49] mmol/L, and GP-UC group, 0.10 [0.53] mmol/L [P = .02]) (to convert to milligrams per deciliter, divide by 0.0555) but not for lipid levels and blood pressure. CONCLUSIONS Lifestyle counseling by NPs did not lead to significantly better prevention of weight gain compared with GPs. In the majority in both groups, lifestyle counseling succeeded in preventing (further) weight gain. TRIAL REGISTRATION trialregister.nl Identifier: NTR1365.


Public Health Nutrition | 2011

Changes in lifestyle habits after counselling by nurse practitioners: 1-year results of the Groningen Overweight and Lifestyle study

Nancy C. W. ter Bogt; Ivon Ej Milder; Wanda J. E. Bemelmans; Frank W. Beltman; Jan Broer; Andries J. Smit; Klaas van der Meer

OBJECTIVES The Groningen Overweight and Lifestyle (GOAL) study primarily aims at preventing weight gain by nurse practitioners (NP) guided by a standardized computerized software program. Since favourable changes in physical activity (PA) and diet may improve health independently of weight (loss), insight into effects on lifestyle habits is essential. We examined the 1-year effects of lifestyle counselling by NP on PA and diet, compared with usual care from the general practitioner (GP-UC). DESIGN A randomized controlled trial. SETTING Eleven general practice locations in the Netherlands. SUBJECTS A total of 341 GOAL participants with overweight or obesity and either hypertension or dyslipidaemia, or both, who completed an FFQ and Short Questionnaire to Assess Health-Enhancing Physical Activity (SQUASH) at baseline and after 1 year. RESULTS After 1 year, the NP group spent 33 min/week more on walking compared with the GP-UC group who spent -5 min/week on walking (P = 0.05). No significant differences were found between the NP and GP-UC groups on the percentage of persons complying with the PA guidelines. In both groups, nutrient intake changed in a favourable direction and participants complied more often with dietary guidelines, but without overall difference between the NP and GP-UC groups. CONCLUSIONS With the exception of an increase in walking (based on self-reported data) in the NP group, no intervention effects on PA and diet occurred. Positive changes in nutrient intake were seen in both groups.


BMC Family Practice | 2012

Randomized controlled trial on cardiovascular risk management by practice nurses supported by self-monitoring in primary care

Ans H Tiessen; Andries J. Smit; Jan Broer; Klaas H. Groenier; Klaas van der Meer

BackgroundTreatment goals for cardiovascular risk management are generally not achieved. Specialized practice nurses are increasingly facilitating the work of general practitioners and self-monitoring devices have been developed as counseling aid. The aim of this study was to compare standard treatment supported by self-monitoring with standard treatment without self-monitoring, both conducted by practice nurses, on cardiovascular risk and separate risk factors.MethodsMen aged 50–75 years and women aged 55–75 years without a history of cardiovascular disease or diabetes, but with a SCORE 10-year risk of cardiovascular mortality ≥5% and at least one treatable risk factor (smoking, hypertension, lack of physical activity or overweight), were randomized into two groups. The control group received standard treatment according to guidelines, the intervention group additionally received pro-active counseling and self-monitoring (pedometer, weighing scale and/ or blood pressure device). After one year treatment effect on 179 participants was analyzed.ResultsSCORE risk assessment decreased 1.6% (95% CI 1.0–2.2) for the control group and 1.8% (1.2–2.4) for the intervention group, difference between groups was .2% (−.6–1.1). Most risk factors tended to improve in both groups. The number of visits was higher and visits took more time in the intervention group (4.9 (SD2.2) vs. 2.6 (SD1.5) visits p < .001 and 27 (P25 –P75:20–33) vs. 23 (P25 –P75:19–30) minutes/visit p = .048).ConclusionsIn both groups cardiovascular risk decreased significantly after one year of treatment by practice nurses. No additional effect of basing the pro-active counseling on self-monitoring was found, despite the extra time investment.Trial registrationtrialregister.nl NTR2188


American Journal of Preventive Medicine | 2009

Preventing Weight Gain

Nancy C. W. ter Bogt; Wanda J. E. Bemelmans; Frank W. Beltman; Jan Broer; Andries J. Smit; Klaas van der Meer

BACKGROUND Lifestyle interventions targeting prevention of weight gain may have better long-term success than when aimed at weight loss. Limited evidence exists about such an approach in the primary care setting. DESIGN An RTC was conducted. SETTING/PARTICIPANTS Participants were 457 overweight or obese patients (BMI=25-40 kg/m(2), mean age 56 years, 52% women) with either hypertension or dyslipidemia, or both, from 11 general practice locations in The Netherlands. INTERVENTION In the intervention group, four individual visits to a nurse practitioner (NP) and one feedback session by telephone were scheduled for lifestyle counseling with guidance of the NP using a standardized computerized software program. The control group received usual care from their general practitioner (GP). MAIN OUTCOME MEASURES Changes in body weight, waist circumference, blood pressure, and blood lipids after 1 year (dropout <10%). Data were collected in 2006 and 2007. Statistical analyses were conducted in 2007 and 2008. RESULTS There were more weight losers and stabilizers in the NP group than in the general practitioner usual care (GP-UC) group (77% vs 65%; p<0.05). In men, mean weight losses were 2.3% for the NP group and 0.1% for the GP-UC group (p<0.05). Significant reductions occurred also in waist circumference but not in blood pressure, blood lipids, and fasting glucose. In women, mean weight losses were in both groups 1.6%. In the NP group, obese people lost more weight (-3.0%) than the non-obese (-1.3%; p<0.05). CONCLUSIONS Standardized computer-guided counseling by NPs may be an effective strategy to support weight-gain prevention and weight loss in primary care, in the current trial, particularly among men. TRIAL REGISTRATION The study was registered with the Netherlands Trial Register (NTR), www.trialregister.nl, study no. TC 1365.


Clinical Chemistry and Laboratory Medicine | 2014

Skin autofluorescence as proxy of tissue AGE accumulation is dissociated from SCORE cardiovascular risk score, and remains so after 3 years.

Ans H Tiessen; Willemein Jager; Nancy C. W. ter Bogt; Frank W. Beltman; Klaas van der Meer; Jan Broer; Andries J. Smit

Abstract Background: Skin autofluorescence (SAF), as a proxy of AGE accumulation, is predictive of cardiovascular (CVD) complications in i.a. type 2 diabetes mellitus and renal failure, independently of most conventional CVD risk factors. The present exploratory substudy of the Groningen Overweight and Lifestyle (GOAL)-project addresses whether SAF is related to Systematic COronary Risk Evaluation (SCORE) risk estimation (% 10-year CVD-mortality risk) in overweight/obese persons in primary care, without diabetes/renal disease, and if after 3-year treatment of risk factors (change in, Δ) SAF is related to ΔSCORE. Methods: In a sample of 65 participants from the GOAL study, with a body mass index (BMI) >25–40 kg/m2, hypertension and/or dyslipidemia, but without diabetes/renal disease, SAF and CVD risk factors were measured at baseline, and after 3 years of lifestyle and pharmaceutical treatment. Results: At baseline, the mean SCORE risk estimation was 3.1±2.6%, mean SAF 2.04±0.5AU. In multivariate analysis SAF was strongly related to age, but not to other risk factors/SCORE. After 3 years ΔSAF was 0.34±0.45 AU (p<0.001). ΔSAF was negatively related to Δbodyweight but not to ΔSCORE%, or its components. At follow-up, SAF was higher in 11 patients with a history of CVD compared to 54 persons without CVD (p=0.002). Conclusions: Baseline and 3-year-Δ SAF are not related to (Δ)SCORE, or its components, except age, in the studied population. ΔSAF was negatively related to Δweight. As 3-year SAF was higher in persons with CVD, these results support a larger study on SAF to assess its contribution to conventional risk factors/SCORE in predicting CVD in overweight persons with low-intermediate cardiovascular risk.

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Andries J. Smit

University Medical Center Groningen

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Klaas van der Meer

University Medical Center Groningen

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Frank W. Beltman

University Medical Center Groningen

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Nancy C. W. ter Bogt

University Medical Center Groningen

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Ans H Tiessen

University Medical Center Groningen

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Jf May

University of Groningen

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Edith J. M. Feskens

Wageningen University and Research Centre

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E.J.M. Feskens

Wageningen University and Research Centre

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