Low micronutrient intake in nursing home residents, a cross-sectional study

Low intake of micronutrients is associated with health-related problems in nursing home residents. As their food intake is generally low, it is expected that their micronutrient intake will be low as well. The nutrient intake of 189 residents (mean age 85.0 years (SD: 7.4)) in five different Dutch nursing homes was measured based on 3-day direct observations of intake. Micronutrient intake, without supplementation, was calculated using the Dutch food composition table, and SPADE software was used to model habitual intake. Intake was compared to the estimated average requirement (EAR) or adequate intake (AI) as described in the Dutch dietary reference values. A low intake was defined as >10% not meeting the EAR or when the P50 (median) intake was below the AI. Vitamin A, thiamin, riboflavin, niacin, B6, folate, B12, C, D, E, copper, iron, zinc, calcium, iodine, magnesium, phosphorus, potassium, and selenium were investigated. Our data showed that vitamin and mineral intake was low for most assessed nutrients. An AI was only seen for vitamin B12 (men only), iodine (men only), and phosphorus. A total of 50% of the population had an intake below the EAR for riboflavin, vit B6, folate, and vitamin D. For reference values expressed in AI, P50 intake of vitamin E, calcium, iodine, magnesium, potassium, and selenium was below the AI. To conclude: micronutrient intake in nursing home residents is far too low in most of the nursing home population. A "food-first" approach could increase dietary intake, but supplements could be considered if the "food-first" approach is not successful.

Behavioral and Cognitive Problems as Determinants of Malnutrition in Long-Term Care Facilities, a Cross-Sectional and Prospective Study

OBJECTIVES

To investigate the cross-sectional and prospective associations between behavior and cognitive problems and malnutrition in long-term care facilities (LTCF).

DESIGN

Cross-sectional and prospective routine care cohort study.

SETTING

6874 Residents in Dutch LTCFs (period 2005-2020).

PARTICIPANTS

Data were obtained from the InterRAI-LTCF instrument. Cross-sectional analyses on prevalence of malnutrition at admission included 3722 residents. Prospective analyses studied incident malnutrition during stay (total follow-up time 7104 years) and included data of 1826 residents with first measurement on admission ('newly-admitted') and n=3152 with first measurement on average ~1 year after admission ('existing').

MEASUREMENTS

InterRAI scales for communication problems (CS), aggressive behavior (ABS), social engagement (RISE), depressive symptoms (DRS), cognitive performance (CPS) and the total number of behavior and cognitive problems were investigated as independent variables and malnutrition (ESPEN 2015 definition) as dependent variable in regression analyses. Results were stratified for gender and group 'newly-admitted' vs. 'existing'.

RESULTS

On admission, 9.5% of residents was malnourished. In men, low social engagement was associated with prevalence of malnutrition. In women, all behavior and cognitive problems except depression were associated with malnutrition in the unadjusted analyses, but this attenuated in the full model taking all problems into account. The incidence of malnutrition during stay amounted to 8.9%. No significant associations of behavior and cognitive problems with malnutrition incidence were seen in 'newly-admitted' male residents while in 'existing' male residents all determinants were significantly associated. In 'newly-admitted' female residents CS, ABS and CPS, and in 'existing' female residents CS, RISE, ABS and CPS were significantly associated with incident malnutrition. All associations slightly attenuated after adjustment. Malnutrition incidence increased with increasing number of combined behavior and cognitive problems.

CONCLUSION

Residents with behavior and cognitive problems are at an increased risk of being malnourished at admission, or becoming malnourished during stay in a LTCF, especially residents with multiple behavior and cognitive problems.

Maintenance interventions for overweight or obesity in children: a systematic review and meta-analysis

Childhood obesity is associated with significant health consequences. Although several intervention programmes for children result in weight loss or stabilization in the short-term, preventing relapse after treatment remains an important challenge. This systematic review summarizes the evidence about maintenance interventions after treatment in childhood obesity. Studies were identified by searching PubMed, Embase, Cochrane Library, Scopus, Web of Science, PsycINFO, CINAHL and SocINDEX. The primary outcome measure for this review was body mass index standard deviation score (BMI-Z-score). Data were pooled using quality effect models. Eleven studies (1,532 participants, age 2-18 years) were included, covering a wide range of maintenance approaches. Included studies varied widely in methodological quality. Pooled analysis showed that the BMI-Z-score of maintenance intervention participants remained stable, whereas control participants experienced a slight increase. No differences were observed regarding intensity and duration of therapy. A slight preference for 'face-to-face' versus 'on distance' interventions was shown. In summary, this review shows that, although there is limited quality data to recommend one maintenance intervention over another, continued treatment does have a stabilizing effect on BMI-Z-score. Considering the magnitude of the problem of childhood obesity, this is an important finding that highlights the need for further research on weight loss maintenance.

Validation of biomarkers of food intake-critical assessment of candidate biomarkers

Biomarkers of food intake (BFIs) are a promising tool for limiting misclassification in nutrition research where more subjective dietary assessment instruments are used. They may also be used to assess compliance to dietary guidelines or to a dietary intervention. Biomarkers therefore hold promise for direct and objective measurement of food intake. However, the number of comprehensively validated biomarkers of food intake is limited to just a few. Many new candidate biomarkers emerge from metabolic profiling studies and from advances in food chemistry. Furthermore, candidate food intake biomarkers may also be identified based on extensive literature reviews such as described in the guidelines for Biomarker of Food Intake Reviews (BFIRev). To systematically and critically assess the validity of candidate biomarkers of food intake, it is necessary to outline and streamline an optimal and reproducible validation process. A consensus-based procedure was used to provide and evaluate a set of the most important criteria for systematic validation of BFIs. As a result, a validation procedure was developed including eight criteria, plausibility, dose-response, time-response, robustness, reliability, stability, analytical performance, and inter-laboratory reproducibility. The validation has a dual purpose: (1) to estimate the current level of validation of candidate biomarkers of food intake based on an objective and systematic approach and (2) to pinpoint which additional studies are needed to provide full validation of each candidate biomarker of food intake. This position paper on biomarker of food intake validation outlines the second step of the BFIRev procedure but may also be used as such for validation of new candidate biomarkers identified, e.g., in food metabolomic studies.

Dairy shows different associations with abdominal and BMI-defined overweight: Cross-sectional analyses exploring a variety of dairy products

BACKGROUND AND AIMS

Previous studies have suggested weight-regulatory properties for several dairy nutrients, but population-based studies on dairy and body weight are inconclusive. We explored cross-sectional associations between dairy consumption and indicators of overweight.

METHODS AND RESULTS

We included 114,682 Dutch adults, aged ≥18 years. Dairy consumption was quantified by a food frequency questionnaire. Abdominal overweight was defined as waist circumference (WC) ≥88 cm (women) or ≥102 cm (men) (n = 37,391), overweight as BMI ≥25-30 kg/m² (n = 44,772) and obesity as BMI ≥30 kg/m² (n = 15,339). Associations were quantified by logistic (abdominal overweight, no/yes), multinomial logistic (BMI-defined overweight and obesity) and linear regression analyses (continuous measures of WC and BMI), and they were adjusted for relevant covariates. Total dairy showed a positive association with abdominal overweight (OR Q1 ref vs. Q5: 1.09; 95% CI: 1.04-1.14) and with BMI-defined overweight (OR Q5 1.13; 95% CI: 1.08-1.18) and obesity (OR Q5 1.09; 95% CI: 1.02-1.16). Skimmed, semi-skimmed and non-fermented dairy also showed positive associations with overweight categories. Full-fat dairy showed an inverse association with overweight and obesity (OR Q5 for obesity: 0.78; 95% CI: 0.73-0.83). Moreover, inverse associations were observed for yoghurt and custard and positive associations for milk, buttermilk, flavoured yoghurt drinks, cheese and cheese snacks. Fermented dairy, curd cheese and Dutch cheese did not show a consistent association with overweight categories.

CONCLUSIONS

Total, skimmed, semi-skimmed and non-fermented dairy; milk; buttermilk; flavoured yoghurt drinks; total cheese and cheese snacks showed a positive association with overweight categories, whereas full-fat dairy, custard and yoghurt showed an inverse association with overweight categories.

Development of a Dutch intervention for obese young children

The objective of this article is to provide insight in the five-step development process of the best evidence, best practice intervention for obese young children 'AanTafel!'. A set of requirements for intervention development was developed to guide the data inquiry: the use of theory, influencing factors, tailoring, multi-disciplinarity, duration/frequency and evaluation and monitoring. Step I retrieved evidence from clinical guidelines, followed by a systematic review with meta-analysis (Step II) and an extended literature review (Step III). Evidence was consistent with regard to parent-focus, targeting family level, including diet, physical activity and behaviour change techniques and tailoring to age. However, no evidence or inconsistent evidence emerged from the theory-basis, group-versus-individual sessions, face-to-face contact versus Internet-mediated contact, which disciplines to involve and how to involve them, as well as intervention duration and intensity. Hence, practice-based insights from parental interviews (Step IV) and involved therapists were added and subsequently integrated to the intervention 'AanTafel!' (Step V). 'AanTafel!' is a multi-component, multi-disciplinary, family-based, parent-focused, age-specific intervention, which is tailored to individual children and families with a duration of 1 year, and using a combination of individual and group sessions as well as a Web-based learning module. Changes in scientific working principles with regard to data collection, reporting and translation to guidelines are required. Practice and science may benefit from close collaboration in designing, implementing and evaluating interventions.

Association of Long-Term Adherence to the MIND Diet with Cognitive Function and Cognitive Decline in American Women

OBJECTIVES

There is increasing attention for dietary patterns as a potential strategy to prevent cognitive decline. We examined the association between adherence to a recently developed Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet with cognitive function and cognitive decline, taking into account the interaction between the apolipoprotein E ε4 genotype and the MIND diet.

DESIGN

Population-based prospective cohort study.

PARTICIPANTS

A total of 16,058 older women aged 70 and over from the Nurses' Health Study.

MEASUREMENTS

Dietary intake was assessed five times between 1984 and 1998 with a 116-item Food Frequency Questionnaire. The MIND score includes ten brain-healthy foods and five unhealthy foods. Cognition was assessed four times by telephone from 1995 to 2001 (baseline) with the Telephone Interview for Cognitive Status (TICS) and by calculating composite scores of verbal memory and global cognition. Linear regression modelling and linear mixed modelling were used to examine the associations of adherence to the MIND diet with average cognitive function and cognitive change over six years, respectively.

RESULTS

Greater long-term adherence to the MIND diet was associated with a better verbal memory score (multivariable-adjusted mean differences between extreme MIND quintiles=0.04 (95%CI 0.01-0.07), p-trend=0.006), but not with cognitive decline over 6 years in global cognition, verbal memory or TICS.

CONCLUSION

Long-term adherence to the MIND diet was moderately associated with better verbal memory in later life. Future studies should address this association within populations at greater risk of cognitive decline.

Habitual diet and diet quality in Irritable Bowel Syndrome: A case-control study

BACKGROUND

Diet is considered to be a key factor in symptom generation in Irritable Bowel Syndrome (IBS) and patients tend to exclude food products from their diet in pursue of symptom relief, which may impair diet quality.

METHODS

We evaluated habitual dietary intake in IBS patients with regard to nutrients and food products using an extensive food frequency questionnaire. One hundred ninety-four IBS patients were compared to 186 healthy controls using multiple logistic regression analysis. An overall diet quality score was calculated for each participant based on the criteria of the Dutch Healthy Diet (DHD) index.

KEY RESULTS

A lower DHD-score was found for IBS (mean [SD]: 52.9 [9.6]) vs controls (55.1 [9.2], P=.02). The diet of patients was lower in fibers (21 g vs 25 g per day, P=.002) and fructose (14 g vs 16 g, P=.033), while higher in total fat (37% vs 36% of total energy intake, P=.010) and added sugars (46 g vs 44 g, P=.029). Differences in daily intake of food products included lower consumption of apples (40 g vs 69 g, P<.001), pasta (28 vs 37 g, P=.029) and alcoholic beverages (130 g vs 193 g, P=.024) and higher consumption of processed meat (38 g vs 29 g, P<.001). Some of these findings correlated with gastrointestinal symptoms, showing differences between IBS subtypes.

CONCLUSIONS AND INFERENCES

Differences in habitual diet were described, showing lower diet quality in IBS patients compared to controls, with increased consumption of fat and lower intake of fibers and fructose. Our data support the importance of personalized and professional nutritional guidance of IBS patients.

Determinants of lifestyle behavior change to prevent type 2 diabetes in high-risk individuals

Background

Although there are many effective lifestyle interventions for type 2 diabetes (T2DM) prevention, insight into effective intervention pathways, especially of long-term interventions, is often lacking. This study aims to provide insight into the effective intervention pathways of the SLIMMER diabetes prevention intervention using mediation analyses.

Methods

In total, 240 participants at increased risk of T2DM were included in the analyses over 18 months. The intervention was a combined lifestyle intervention with a dietary and a physical activity (PA) component. The primary and secondary outcomes were change in fasting insulin (pmol/L) and change in body weight (kg) after 18 months, respectively. Firstly, in a multiple mediator model, we investigated whether significant changes in these outcomes were mediated by changes in dietary and PA behavior. Secondly, in multiple single mediator models, we investigated whether changes in dietary and PA behavior were mediated by changes in behavioral determinants and the participants’ psychological profile. The mediation analyses used linear regression models, where significance of indirect effects was calculated with bootstrapping.

Results

The effect of the intervention on decreased fasting insulin was 40% mediated by change in dietary and PA behavior, where dietary behavior was an independent mediator of the association (34%). The effect of the intervention on decreased body weight was 20% mediated by change in dietary and PA behavior, where PA behavior was an independent mediator (17%). The intervention significantly changed intake of fruit, fat from bread spread, and fiber from bread. Change in fruit intake was mediated by change in action control (combination of consciousness, self-control, and effort), motivation, self-efficacy, intention, and skills. Change in fat intake was mediated by change in action control and psychological profile. No mediators could be identified for change in fiber intake. The change in PA behavior was mediated by change in action control, motivation, and psychological profile.

Conclusion

The effect of the SLIMMER intervention on fasting insulin and body weight was mediated by changes in dietary and PA behavior, in distinct ways. These results indicate that changing dietary as well as PA behavior is important in T2DM prevention.

Electronic supplementary material

The online version of this article (doi:10.1186/s12966-017-0532-9) contains supplementary material, which is available to authorized users.

Effect and maintenance of the SLIMMER diabetes prevention lifestyle intervention in Dutch primary healthcare: a randomised controlled trial

BACKGROUND/OBJECTIVES

To assess the effectiveness of the SLIMMER combined dietary and physical activity lifestyle intervention on clinical and metabolic risk factors, dietary intake, physical activity, and quality of life after 12 months, and to investigate whether effects sustained six months after the active intervention period ended.

SUBJECTS/METHODS

SLIMMER was a randomised controlled intervention, implemented in Dutch primary healthcare. In total, 316 subjects aged 40-70 years with increased risk of type 2 diabetes were randomly allocated to the intervention group (10-month dietary and physical activity programme) or the control group (usual healthcare). All subjects underwent an oral glucose tolerance test and physical examination, and filled in questionnaires. Identical examinations were performed at baseline and after 12 and 18 months. Primary outcome was fasting insulin.

RESULTS

The intervention group showed significantly greater improvements in anthropometry and glucose metabolism. After 12 and 18 months, differences between intervention and control group were -2.7 kg (95% confidence interval (CI): -3.7; -1.7) and -2.5 kg (95% CI: -3.6; -1.4) for weight, and -12.1 pmol l-1 (95% CI: -19.6; -4.6) and -8.0 pmol l-1 (95% CI: -14.7; -0.53) for fasting insulin. Furthermore, dietary intake, physical activity, and quality of life improved significantly more in the intervention group than in the control group.

CONCLUSIONS

The Dutch SLIMMER lifestyle intervention is effective in the short and long term in improving clinical and metabolic risk factors, dietary intake, physical activity, and quality of life in subjects at high risk of diabetes.

Alcohol and red wine consumption, but not fruit, vegetables, fish or dairy products, are associated with less endothelial dysfunction and less low-grade inflammation: the Hoorn Study

Purpose

Endothelial dysfunction and low-grade inflammation are key phenomena in the pathobiology of cardiovascular disease (CVD). Their dietary modification might explain the observed reduction in CVD that has been associated with a healthy diet rich in fruit, vegetables and fish, low in dairy products and with moderate alcohol and red wine consumption. We investigated the associations between the above food groups and endothelial dysfunction and low-grade inflammation in a population-based cohort of Dutch elderly individuals.

Methods

Diet was measured by food frequency questionnaire (n = 801; women = 399; age 68.5 ± 7.2 years). Endothelial dysfunction was determined (1) by combining von Willebrand factor, and soluble intercellular adhesion molecule 1 (sICAM-1), vascular cell adhesion molecule 1, endothelial selectin and thrombomodulin, using Z-scores, into a biomarker score and (2) by flow-mediated vasodilation (FMD), and low-grade inflammation by combining C-reactive protein, serum amyloid A, interleukin 6, interleukin 8, tumour necrosis factor α and sICAM-1 into a biomarker score, with smaller FMD and higher scores representing more dysfunction and inflammation, respectively. We used linear regression analyses to adjust associations for sex, age, energy, glucose metabolism, body mass index, smoking, prior CVD, educational level, physical activity and each of the other food groups.

Results

Moderate [β (95% CI) −0.13 (−0.33; 0.07)] and high [−0.22 (−0.45; −0.003)] alcohol consumption, and red wine [−0.16 (−0.30; −0.01)] consumption, but none of the other food groups, were associated with a lower endothelial dysfunction biomarker score and a greater FMD. The associations for FMD were, however, not statistically significant. Only red wine consumption was associated with a lower low-grade inflammation biomarker score [−0.18 (−0.33; −0.04)].

Conclusions

Alcohol and red wine consumption may favourably influence processes involved in atherothrombosis.

Electronic supplementary material

The online version of this article (doi:10.1007/s00394-017-1420-4) contains supplementary material, which is available to authorized users.

Intake of different types of dairy and its prospective association with risk of type 2 diabetes: The Rotterdam Study

BACKGROUND AND AIMS

The prevalence of type 2 diabetes (T2DM) is increasing. Several studies have suggested a beneficial effect of several major dairy nutrients on insulin production and sensitivity. Conversely, harmful effects have been suggested as well. This study aimed to investigate the impact of the full-range of dairy products and its association with incidence T2DM in Dutch adults aged ≥55 years participating in the Rotterdam Study.

METHODS AND RESULTS

Dairy intake was assessed with a validated FFQ, including total, skimmed, semi-skimmed, full-fat, fermented, and non-fermented dairy, and subclasses of these product groups. Verified prevalent and incident diabetes were documented. Cox proportional hazards regression and spline regression were used to analyse data, adjusting for age, sex, alcohol, smoking, education, physical activity, body mass index, intake of total energy, energy-adjusted meat, and energy-adjusted fish intake. Median total dairy intake was 398 g/day (IQR 259-559 g/day). Through 9.5 ± 4.1 years of follow-up, 393 cases of incident T2DM were reported. Cox and spline regression did not point towards associations of total dairy consumption, dairy consumption based on fat content, non-fermented or fermented dairy consumption, or individual dairy product consumption with incident T2DM. The HR for total dairy intake and T2DM was 0.93 (95% CI: 0.70-1.23) in the upper quartile (P-for trend 0.76).

CONCLUSIONS

This prospective cohort study did not point towards an association between dairy consumption and T2DM.

Low vitamin D status is associated with more depressive symptoms in Dutch older adults

Purpose

The existence of vitamin D receptors in the brain points to a possible role of vitamin D in brain function. We examined the association of vitamin D status and vitamin D-related genetic make-up with depressive symptoms amongst 2839 Dutch older adults aged ≥65 years.

Methods

25-Hydroxyvitamin D (25(OH)D) was measured, and five ‘vitamin D-related genes’ were selected. Depressive symptoms were measured with the 15-point Geriatric Depression Scale. Results were expressed as the relative risk of the score of depressive symptoms by quartiles of 25(OH)D concentration or number of affected alleles, using the lowest quartile or minor allele group as reference.

Results

A clear cross-sectional and prospective association between serum 25(OH)D and depressive symptom score was observed. Fully adjusted models indicated a 22 % (RR 0.78, 95 % CI 0.68–0.89), 21 % (RR 0.79, 95 % CI 0.68–0.90), and 18 % (RR 0.82, 95 % CI 0.71–0.95) lower score of depressive symptoms in people in the second, third, and fourth 25(OH)D quartiles, when compared to people in the first quartile (P for trend <0.0001). After 2 years of daily 15 µg vitamin D supplementation, similar associations were observed. 25(OH)D concentrations did not significantly interact with the selected genes.

Conclusion

Low serum 25(OH)D was associated with higher depressive symptom scores. No interactions between 25(OH)D concentrations and vitamin D genetic make-up were observed. In view of the probability of reverse causation, we propose that the association should be further examined in prospective studies as well as in randomized controlled trials.

Electronic supplementary material

The online version of this article (doi:10.1007/s00394-015-0970-6) contains supplementary material, which is available to authorized users.

Review article: the association of diet with onset and relapse in patients with inflammatory bowel disease

BACKGROUND

The role of diet in inflammatory bowel disease (IBD) is supported by migration studies and increasing incidences in line with Westernisation.

AIM

To give a complete overview of studies associating habitual diet with the onset or relapses in ulcerative colitis (UC) or Crohn's disease (CD).

METHODS

A structured search in Pubmed, the Cochrane Library and EMBASE was performed using defined key words, including only full text papers in English language.

RESULTS

Forty-one studies were identified, investigating onset (n = 35), relapses (n = 5) or both (n = 1). Several studies reported high intake of sugar or sugar-containing foods (n = 7 UC, n = 12 CD), and low intake of fruits and/or vegetables (n = 5 UC, n = 10 CD) to be associated with an increased onset risk. However, these findings could not be confirmed by similar or higher numbers of other studies. A possible protective role was found for grain-derived products in CD onset, but results were inconsistent for dietary fibre in UC and CD and grain-derived products in UC. No definite conclusions could be drawn for unsaturated fatty acids (UFA), protein and energy intake due to limited and/or inconsistent results. Six studies reported on diet and relapse risk, of which only two (n = 1 UC, n = 1 CD) had a prospective follow-up.

CONCLUSIONS

The current evidence is not sufficient to draw firm conclusions on the role of specific food components or nutrients in the aetiology of IBD. Furthermore, large prospective studies into the role of habitual diet as a trigger of relapses are needed, to identify new therapeutic or preventive targets.

Satiety and energy intake after single and repeated exposure to gel-forming dietary fiber: post-ingestive effects

BACKGROUND

Viscous or gel-forming dietary fibers can increase satiety by a more firm texture and increased eating time. Effects of viscous or gel-forming fibers on satiety by post-ingestive mechanisms such as gastric emptying, hormonal signals, nutrient absorption or fermentation are unclear. Moreover, it is unclear whether the effects persist after repeated exposure.

OBJECTIVE

To investigate satiety and energy intake after single and repeated exposure to gelled fiber by post-ingestive mechanisms.

DESIGN

In a two-arm crossover design, 32 subjects (24 female subjects, 21±2 y, BMI 21.8±1.9 kg m(-2)) consumed test foods once daily for 15 consecutive days, with 2 weeks of washout. Test foods were isocaloric (0.5 MJ, 200 g) with either 10 g gel-forming pectin or 3 g gelatin and 2 g starch, matched for texture and eating time. Hourly satiety ratings, ad libitum energy intake and body weight were measured on days 1 (single exposure) and 15 (repeated exposure). In addition, hourly breath hydrogen, fasting glucose, insulin, leptin and short-chain fatty acids were measured.

RESULTS

Subjects rated hunger, desire to eat and prospective intake about 2% lower (P<0.015) and fullness higher (+1.4%; P=0.041) when they received pectin compared with control. This difference was similar after single and repeated exposure (P>0.64). After receiving pectin, energy intake was lower (-5.6%, P=0.012) and breath hydrogen was elevated (+12.6%, P=0.008) after single exposure, but not after repeated exposure. Fasting glucose concentrations were higher both after single and repeated exposure to pectin (+2.1%, P=0.019). Body weight and concentrations of insulin, leptin and short-chain fatty acids did not change during the study.

CONCLUSIONS

Gelled pectin can increase satiety and reduce energy intake by post-ingestive mechanisms. Although the effects were small, the effects on satiety were consistent over time, whereas the effects on energy intake reduction were not.

Consumption of sweet beverages and type 2 diabetes incidence in European adults: results from EPIC-InterAct

AIMS/HYPOTHESIS

Consumption of sugar-sweetened beverages has been shown, largely in American populations, to increase type 2 diabetes incidence. We aimed to evaluate the association of consumption of sweet beverages (juices and nectars, sugar-sweetened soft drinks and artificially sweetened soft drinks) with type 2 diabetes incidence in European adults.

METHODS

We established a case-cohort study including 12,403 incident type 2 diabetes cases and a stratified subcohort of 16,154 participants selected from eight European cohorts participating in the European Prospective Investigation into Cancer and Nutrition (EPIC) study. After exclusions, the final sample size included 11,684 incident cases and a subcohort of 15,374 participants. Cox proportional hazards regression models (modified for the case-cohort design) and random-effects meta-analyses were used to estimate the association between sweet beverage consumption (obtained from validated dietary questionnaires) and type 2 diabetes incidence.

RESULTS

In adjusted models, one 336 g (12 oz) daily increment in sugar-sweetened and artificially sweetened soft drink consumption was associated with HRs for type 2 diabetes of 1.22 (95% CI 1.09, 1.38) and 1.52 (95% CI 1.26, 1.83), respectively. After further adjustment for energy intake and BMI, the association of sugar-sweetened soft drinks with type 2 diabetes persisted (HR 1.18, 95% CI 1.06, 1.32), but the association of artificially sweetened soft drinks became statistically not significant (HR 1.11, 95% CI 0.95, 1.31). Juice and nectar consumption was not associated with type 2 diabetes incidence.

CONCLUSIONS/INTERPRETATION

This study corroborates the association between increased incidence of type 2 diabetes and high consumption of sugar-sweetened soft drinks in European adults.

Vitamin D: do we get enough? A discussion between vitamin D experts in order to make a step towards the harmonisation of dietary reference intakes for vitamin D across Europe

On September 29, 2011, acknowledged experts in the field of vitamin D, mainly European, were brought together in order to discuss the recent scientific advances in relation to vitamin D: the current requirements and associations with various health outcomes. In this article, the discussions resulting from the meeting are summarized.

INTRODUCTION

Several groups at risk for developing vitamin D insufficiency have been identified. Accordingly, reviews indicate that a significant percentage of the population worldwide have serum 25-hydroxyvitamin D levels below 50 nmol/l. In addition to the role of vitamin D in bone health, recent studies suggest that it may play a pivotal role in other systems, e.g., the cardiovascular system, pancreas, muscle, immune system and brain. Most evidence, however, is obtained from observational studies and yet inconclusive.

METHODS

To exchange and broaden knowledge on the requirements for vitamin D and its effect on various health outcomes, a workshop entitled "Vitamin D Expert Meeting: Do we get enough?", was organized.

RESULTS

Despite low vitamin D levels worldwide, consensus on the definition of deficiency is not yet reached. In order to define cut-off points for vitamin D whilst taking into account extraskeletal health effects, randomized controlled trials in these fields are warranted. The experts do emphasize that there is evidence to suggest an important role for vitamin D in the maintenance of optimal bone health at all ages and that vitamin D supplementation, in most studies co-administered with calcium, reduces fracture risk in the senior population.

CONCLUSION

To reach a serum 25-hydroxyvitamin D level of 50 nmol/l older adults aged ≥65 years are therefore recommended to meet a mean daily vitamin D intake of 20 μg (800 IU), which is best achieved with a supplement.

Regional differences of HFE (C282Y, H63D) allele frequencies in the Netherlands A model case illustrating the significance of genographics and prehistorical population migration

We investigated HFE C282Y and H63D allele frequencies in three Dutch towns in the Netherlands, as well as their association with cardiovascular disease (CVD) mortality. Study subjects were selected from participants of the Monitoring Project on Cardiovascular Disease Risk Factors in the Netherlands carried out in Amsterdam, Doetinchem and Maastricht among > 35000 subjects, 20-59 years of age. Mortality follow-up lasted 9 to 13 years. A random sample of the cohort (n = 1075) provided information on the total study population. The random sample and all CVD deaths (n = 301) were genotyped for the C282Y and H63D mutation. Adjusted hazard ratios (HR) for CVD mortality were calculated per genotype. C282Y allele frequencies differed significantly between the towns investigated (p = 0.017), whereas the allele frequencies of H63D were similar (p = 0.141) across towns. In Maastricht we found a C282Y allele frequency of 0.086 compared to 0.055 in Amsterdam and 0.054 in Doetinchem. C282Y and H63D heterozygosity did not predict fatal CVD in either men or women, whereas homozygosity for the H63D mutation increased fatal CVD in women (adjusted HR = 8.5; 95% CI = 2.3-31.1). The unexpected high C282Y allele frequency in Maastricht is in line with the recent evidence of a Celtic origin of citizens from the former southern Netherlands and with prehistorical population migrations revealed in the context of the international Genographic Project, a landmark study of prehistorical human migrations around the globe. We recommend that when designing national screening programmes and national registries for genetic disorders, potential regional prevalence differences should be taken into account.

Association between dietary meat consumption and incident type 2 diabetes: the EPIC-InterAct study

AIMS/HYPOTHESIS

A diet rich in meat has been reported to contribute to the risk of type 2 diabetes. The present study aims to investigate the association between meat consumption and incident type 2 diabetes in the EPIC-InterAct study, a large prospective case-cohort study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) study.

METHODS

During 11.7 years of follow-up, 12,403 incident cases of type 2 diabetes were identified among 340,234 adults from eight European countries. A centre-stratified random subsample of 16,835 individuals was selected in order to perform a case-cohort design. Prentice-weighted Cox regression analyses were used to estimate HR and 95% CI for incident diabetes according to meat consumption.

RESULTS

Overall, multivariate analyses showed significant positive associations with incident type 2 diabetes for increasing consumption of total meat (50 g increments: HR 1.08; 95% CI 1.05, 1.12), red meat (HR 1.08; 95% CI 1.03, 1.13) and processed meat (HR 1.12; 95% CI 1.05, 1.19), and a borderline positive association with meat iron intake. Effect modifications by sex and class of BMI were observed. In men, the results of the overall analyses were confirmed. In women, the association with total and red meat persisted, although attenuated, while an association with poultry consumption also emerged (HR 1.20; 95% CI 1.07, 1.34). These associations were not evident among obese participants.

CONCLUSIONS/INTERPRETATION

This prospective study confirms a positive association between high consumption of total and red meat and incident type 2 diabetes in a large cohort of European adults.

Alcohol consumption and risk of type 2 diabetes in European men and women: influence of beverage type and body size The EPIC-InterAct study

OBJECTIVE

To investigate the association between alcohol consumption and type 2 diabetes, and determine whether this is modified by sex, body mass index (BMI) and beverage type.

DESIGN

Multicentre prospective case-cohort study.

SETTING

Eight countries from the European Prospective Investigation into Cancer and Nutrition cohort.

SUBJECTS

A representative baseline sample of 16 154 participants and 12 403 incident cases of type 2 diabetes.

INTERVENTIONS

Alcohol consumption assessed using validated dietary questionnaires.

MAIN OUTCOME MEASURES

Occurrence of type 2 diabetes based on multiple sources (mainly self-reports), verified against medical information.

RESULTS

Amongst men, moderate alcohol consumption was nonsignificantly associated with a lower incidence of diabetes with a hazard ratio (HR) of 0.90 (95% CI: 0.78-1.05) for 6.1-12.0 versus 0.1-6.0 g day(-1) , adjusted for dietary and diabetes risk factors. However, the lowest risk was observed at higher intakes of 24.1-96.0 g day(-1) with an HR of 0.86 (95% CI: 0.75-0.98). Amongst women, moderate alcohol consumption was associated with a lower incidence of diabetes with a hazard ratio of 0.82 (95% CI: 0.72-0.92) for 6.1-12.0 g day(-1) (P interaction gender <0.01). The inverse association between alcohol consumption and diabetes was more pronounced amongst overweight (BMI ≥ 25 kg m(-2) ) than normal-weight men and women (P interaction < 0.05). Adjusting for waist and hip circumference did not alter the results for men, but attenuated the association for women (HR=0.90, 95% CI: 0.79-1.03 for 6.1-12.0 g day(-1) ). Wine consumption for men and fortified wine consumption for women were most strongly associated with a reduced risk of diabetes.

CONCLUSIONS

The results of this study show that moderate alcohol consumption is associated with a lower risk of type 2 diabetes amongst women only. However, this risk reduction is in part explained by fat distribution. The relation between alcohol consumption and type 2 diabetes was stronger for overweight than normal-weight women and men.

Fruit and vegetable intake and type 2 diabetes: EPIC-InterAct prospective study and meta-analysis

Fruit and vegetable intake (FVI) may reduce the risk of type 2 diabetes (T2D), but the epidemiological evidence is inconclusive. The aim of this study is to examine the prospective association of FVI with T2D and conduct an updated meta-analysis. In the European Prospective Investigation into Cancer-InterAct (EPIC-InterAct) prospective case-cohort study nested within eight European countries, a representative sample of 16,154 participants and 12,403 incident cases of T2D were identified from 340,234 individuals with 3.99 million person-years of follow-up. For the meta-analysis we identified prospective studies on FVI and T2D risk by systematic searches of MEDLINE and EMBASE until April 2011. In EPIC-InterAct, estimated FVI by dietary questionnaires varied more than twofold between countries. In adjusted analyses the hazard ratio (95% confidence interval) comparing the highest with lowest quartile of reported intake was 0.90 (0.80-1.01) for FVI; 0.89 (0.76-1.04) for fruit and 0.94 (0.84-1.05) for vegetables. Among FV subtypes, only root vegetables were inversely associated with diabetes 0.87 (0.77-0.99). In meta-analysis using pooled data from five studies including EPIC-InterAct, comparing the highest with lowest category for FVI was associated with a lower relative risk of diabetes (0.93 (0.87-1.00)). Fruit or vegetables separately were not associated with diabetes. Among FV subtypes, only green leafy vegetable (GLV) intake (relative risk: 0.84 (0.74-0.94)) was inversely associated with diabetes. Subtypes of vegetables, such as root vegetables or GLVs may be beneficial for the prevention of diabetes, while total FVI may exert a weaker overall effect.

Comparison of fatty acid proportions in serum cholesteryl esters among people with different glucose tolerance status: the CoDAM study

BACKGROUND AND AIM

Altered fatty acid patterns in blood may be associated with insulin resistance and related disorders. We investigated whether serum proportions of cholesteryl fatty acids and desaturase activity are associated with glucose tolerance status and insulin resistance.

METHODS AND RESULTS

Data were obtained from a cross-sectional study among 471 Dutch participants aged ≥40 years. Individual fatty acids in serum cholesteryl esters were determined and endogenous conversions by desaturases were estimated from product-to-precursor ratios. Proportions of fatty acids were compared among participants with normal glucose tolerance, impaired glucose metabolism and newly diagnosed type 2 diabetes. Partial Spearman correlation coefficients between fatty acids and homeostasis model assessment-insulin resistance (HOMA-IR) were calculated. Adjustments were made for lifestyle and nutritional factors. The proportions of total saturated, mono-unsaturated, trans- and poly-unsaturated fatty acids did not differ significantly between groups, but several individual fatty acids did; the proportions of C18:0 and C20:3n6 were higher, whereas those of C18:1n7 and C20:4n6 were lower in participants with type 2 diabetes compared with those with normal glucose tolerance. Activity of Δ5-desaturase, that is, ratio of C20:4n6 to C20:3n6, was lower (p < 0.01) in participants with type 2 diabetes (7.4) than with normal glucose tolerance (8.4). HOMA-IR was correlated positively with Δ9-desaturase activity (r = 0.11, p < 0.01) and inversely with Δ5-desaturase activity (r = -0.21, p < 0.01).

CONCLUSION

The observed lower Δ5-desaturase activity in participants with type 2 diabetes and its inverse association with HOMA-IR suggest that changes in fatty-acid metabolism may play a role in the aetiology of type 2 diabetes.

Shared genetic variance between the features of the metabolic syndrome: heritability studies

Heritability estimates of MetS range from approximately 10%-30%. The genetic variation that is shared among MetS features can be calculated by genetic correlation coefficients. The objective of this paper is to identify MetS feature as well as MetS related features which have much genetic variation in common, by reviewing the literature regarding genetic correlation coefficients. Identification of features, that have much genetic variation in common, may eventually facilitate the search for pleitropic genetic variants that may explain the clustering of MetS features. A PubMed search with the search terms "(metabolic syndrome OR insulin resistance syndrome) and (heritability OR genetic correlation OR pleiotropy)" was performed. Studies published before 7th July 2011, which presented genetic correlation coefficients between the different MetS features and genetic correlation coefficients of MetS and its features with adipose tissue-, pro-inflammatory and pro-thrombotic biomarkers were included. Nine twin and 19 family studies were included in the review. Genetic correlations varied, but were strongest between waist circumference and HOMA-IR (r(2): 0.36 to 0.79, median: 0.50), HDL cholesterol and triglycerides (r(2): -0.05 to -0.59, median -0.45), adiponectin and MetS (r(2): -0.32 to -0.43; median -0.38), adiponectin and insulin (r(2): -0.10 to -0.60; median -0.30) and between adiponectin and HDL-cholesterol (r(2): -0.22 to -0.51, median -0.29). In conclusion, heritability studies suggest that genetic pleiotropy exist especially between certain MetS features, as well as between MetS and adiponectin. Further research on actual genetic variants responsible for the genetic pleiotropy of these combinations will provide more insight into the etiology of MetS.

Genetic variants and the metabolic syndrome: a systematic review

Several candidate gene studies on the metabolic syndrome (MetS) have been conducted. However, for most single nucleotide polymorphisms (SNPs) no systematic review on their association with MetS exists. A systematic electronic literature search was conducted until the 2nd of June 2010, using HuGE Navigator. English language articles were selected. Only genes of which at least one SNP-MetS association was studied in an accumulative total population ≥ 4000 subjects were included. Meta-analyses were conducted on SNPs with three or more studies available in a generally healthy population. In total 88 studies on 25 genes were reviewed. Additionally, for nine SNPs in seven genes (GNB3, PPARG, TCF7L2, APOA5, APOC3, APOE, CETP) a meta-analysis was conducted. The minor allele of rs9939609 (FTO), rs7903146 (TCF7L2), C56G (APOA5), T1131C (APOA5), C482T (APOC3), C455T (APOC3) and 174G>C (IL6) were more prevalent in subjects with MetS, whereas the minor allele of Taq-1B (CETP) was less prevalent in subjects with the MetS. After having systematically reviewed the most studied SNP-MetS associations, we found evidence for an association with the MetS for eight SNPs, mostly located in genes involved in lipid metabolism.

Effects of dietary fibre on subjective appetite, energy intake and body weight: a systematic review of randomized controlled trials

Dietary fibres are believed to reduce subjective appetite, energy intake and body weight. However, different types of dietary fibre may affect these outcomes differently. The aim of this review was to systematically investigate the available literature on the relationship between dietary fibre types, appetite, acute and long-term energy intake, and body weight. Fibres were grouped according to chemical structure and physicochemical properties (viscosity, solubility and fermentability). Effect rates were calculated as the proportion of all fibre-control comparisons that reduced appetite (n = 58 comparisons), acute energy intake (n = 26), long-term energy intake (n = 38) or body weight (n = 66). For appetite, acute energy intake, long-term energy intake and body weight, there were clear differences in effect rates depending on chemical structure. Interestingly, fibres characterized as being more viscous (e.g. pectins, β-glucans and guar gum) reduced appetite more often than those less viscous fibres (59% vs. 14%), which also applied to acute energy intake (69% vs. 30%). Overall, effects on energy intake and body weight were relatively small, and distinct dose-response relationships were not observed. Short- and long-term effects of dietary fibres appear to differ and multiple mechanisms relating to their different physicochemical properties seem to interplay. This warrants further exploration.

Effect of a high monounsaturated fatty acids diet and a Mediterranean diet on serum lipids and insulin sensitivity in adults with mild abdominal obesity

BACKGROUND AND AIMS

Diets high in monounsaturated fatty acids (MUFA) such as a Mediterranean diet may reduce the risk of cardiovascular diseases by improving insulin sensitivity and serum lipids. Besides being high in MUFA, a Mediterranean diet also contains abundant plant foods, moderate wine and low amounts of meat and dairy products, which may also play a role. We compared the effects of a high MUFA-diet with a diet high in saturated fatty acids (SFA) and the additional effect of a Mediterranean diet on insulin sensitivity and serum lipids.

METHODS AND RESULTS

A randomized parallel controlled-feeding trial was performed, in 60 non-diabetics (40-65 y) with mild abdominal obesity. After a two week run-in diet high in SFA (19 energy-%), subjects were allocated to a high MUFA-diet (20 energy-%), a Mediterranean diet (MUFA 21 energy-%), or the high SFA-diet, for eight weeks. The high MUFA and the Mediterranean diet did not affect fasting insulin concentrations. The high MUFA-diet reduced total cholesterol (-0.41 mmol/L, 95% CI -0.74, -0.09) and LDL-cholesterol (-0.38 mmol/L, 95% CI -0.65, -0.11) compared with the high SFA-diet, but not triglyceride concentrations. The Mediterranean diet increased HDL-cholesterol concentrations (+0.09 mmol/L, 95% CI 0.0, 0.18) and reduced the ratio of total cholesterol/HDL-cholesterol (-0.39, 95% CI -0.62, -0.16) compared with the high MUFA-diet.

CONCLUSION

Replacing a high SFA-diet with a high MUFA or a Mediterranean diet did not affect insulin sensitivity, but improved serum lipids. The Mediterranean diet was most effective, it reduced total and LDL-cholesterol, and also increased HDL-cholesterol and reduced total cholesterol/HDL-cholesterol ratio.

Low-grade inflammation can partly explain the association between the metabolic syndrome and either coronary artery disease or severity of peripheral arterial disease: the CODAM study

BACKGROUND

Low-grade inflammation has been hypothesized to underlie the coronary artery disease (CAD) risk associated with the metabolic syndrome, but the evidence is not conclusive. For peripheral arterial disease (PAD; as measured by the ankle-arm index), this association has not been studied before. The aim was to study whether the association between the metabolic syndrome and CAD or the severity of PAD can be explained by low-grade inflammation.

METHODS

The Cohort study Diabetes and Atherosclerosis Maastricht population includes 574 subjects, with an increased risk of type 2 diabetes, of whom 560 were included in the analyses (343 males; age: 59.5 +/- 7.0 years). The inflammation markers that were measured were C-reactive protein, interleukin 6, soluble vascular cell adhesion molecule-1, soluble intercellular adhesion molecule-1 and serum amyloid A. All analyses were adjusted for age, sex and smoking.

RESULTS

Logistic regression showed that the metabolic syndrome was significantly associated with CAD [odds ratio (OR) = 1.86, 95% CI: 1.21; 2.84, P = 0.004]. Further adjustment for inflammatory status, as captured in a combination of the inflammation markers (using an averaged Z-score), resulted in significant associations of both the metabolic syndrome and inflammatory status with CAD [OR(metabolic syndrome) (95% CI) = 1.58 (1.01; 2.46), P = 0.044; OR(inflammation) (95% CI) = 1.59 (1.14; 2.21), P = 0.007]. Linear regression analysis showed similar results for the ankle-arm index.

CONCLUSIONS

The association between the metabolic syndrome, on the one hand, and prevalence of CAD or the severity of PAD, on the other, can be partly but not completely, 26% and 29% respectively, explained by low-grade inflammation.

Systematically missing confounders in individual participant data meta-analysis of observational cohort studies

One difficulty in performing meta-analyses of observational cohort studies is that the availability of confounders may vary between cohorts, so that some cohorts provide fully adjusted analyses while others only provide partially adjusted analyses. Commonly, analyses of the association between an exposure and disease either are restricted to cohorts with full confounder information, or use all cohorts but do not fully adjust for confounding. We propose using a bivariate random-effects meta-analysis model to use information from all available cohorts while still adjusting for all the potential confounders. Our method uses both the fully adjusted and the partially adjusted estimated effects in the cohorts with full confounder information, together with an estimate of their within-cohort correlation. The method is applied to estimate the association between fibrinogen level and coronary heart disease incidence using data from 154 012 participants in 31 cohorts.† Copyright © 2009 John Wiley & Sons, Ltd.

Changes in transferrin are related to changes in insulin resistance: the SLIM study

AIMS

To determine the effect of a lifestyle intervention on serum transferrin and ferritin levels and the relationship between changes in transferrin and ferritin and changes in glucose tolerance and insulin resistance.

METHODS

Randomized controlled lifestyle intervention directed at a healthy diet and increased physical activity in subjects with impaired glucose tolerance.

RESULTS

After 1 year, the change in ferritin levels in the intervention group as compared with the control group did not reach statistical significance (P = 0.06). Transferrin change was independently related to the change in homeostasis model assessment of insulin resistance and ferritin change was related to the change in 2-h free fatty acids.

CONCLUSIONS

Changes in insulin sensitivity and postprandial lipid metabolism are related to changes in iron metabolism.

[Finnish questionnaire reasonably good predictor of the incidence of diabetes in The Netherlands]

OBJECTIVE

To establish whether the Finnish diabetes risk score for predicting the incidence of diabetes (FINDRISK) is also valid in the Netherlands, and to choose cut-off points suitable for the Dutch situation.

DESIGN

. Descriptive.

METHOD

The FINDRISK was validated in 3 Dutch cohort studies by means of repeated glucose measurements: the Hoorn study (n=5434), the PREVEND study (n=2713) and part of the Maastricht cohort from the MORGEN study (n=863). The predictive value was evaluated using receiver operating characteristic (ROC) analyses. The risk categories were defined on the basis of sensitivity, specificity and positive predictive value.

RESULTS

The predictive value of the FINDRISK was best in the PREVEND cohort (area under the ROC curve 0.77) and was lower for the Hoorn study and the Maastricht cohort (area under the ROC-curve 0.71 for both). The scores were divided into three risk categories: low risk (score lower than 7), slightly increased risk (score 7-9) and increased risk (score so or higher). The percentage of persons with incident diabetes within about 5 years was < 6 in the low risk category, 6-14 in the category with slightly increased risk and 12-26 in the category with increased risk. 16-28% of the Dutch population studied had a score of 10 or higher.

CONCLUSION

The FINDRISK is a reasonably good predictor for incident diabetes in the Netherlands.

Impact of 3-year lifestyle intervention on postprandial glucose metabolism: the SLIM study

OBJECTIVE

To determine the effect of a 3-year diet and exercise lifestyle intervention, based on general public health recommendations, on glucose tolerance, insulin resistance and metabolic cardiovascular risk factors in Dutch subjects with impaired glucose tolerance (IGT).

METHODS

The study was a randomized controlled lifestyle intervention over 3 years. A total of 147 IGT subjects (75 male, 72 female) were randomized to the intervention (INT) group or control (CON) group; 106 subjects (52 INT, 54 CON) completed 3 years of intervention. Annually, glucose, insulin and free fatty acid (FFA) concentrations were determined fasting and after an oral glucose tolerance test. Measurements of body weight, serum lipids, blood pressure and maximal aerobic capacity were also performed.

RESULTS

Analysis of those who completed the 3-year trial, showed that the lifestyle intervention improved body weight (INT -1.08 +/- 4.30 kg; CON +0.16 +/- 4.91 kg, P = 0.01), homeostatis model assessment index for insulin resistance and 2-h FFA. Two-hour glucose concentrations improved in the INT group, the difference being most pronounced after 1 year, with a return to baseline values after 3 years, from 8.59 +/- 1.55 to 8.55 +/- 0.34 mm; in contrast, 2-h glucose deteriorated in the CON group-from 8.46 +/- 1.84 to 9.35 +/- 2.50 mm (P = 0.02). In the INT group, diabetes incidence was reduced by 58% (P = 0.025).

CONCLUSION

Our lifestyle intervention showed a sustained beneficial effect on 2-h glucose concentrations, insulin resistance and 2-h FFA, even after 3 years. Our lifestyle intervention is effective, but for implementation more information is needed about factors influencing adherence.

Paraoxonase 1 phenotype distribution and activity differs in subjects with newly diagnosed Type 2 diabetes (the CODAM Study)

AIMS

Paraoxonase 1 (PON1) is an antioxidant high-density lipoprotein-bound enzyme, which was recently found to be expressed in the islets of Langerhans. A substitution (Q/R) at position 192 results in enzymes with different activity. Oxidation has been implicated in the onset of diabetes, and it can be hypothesized that PON1 may have a protective effect on diabetes. Our aim was to compare PON1 activities and PON1 Q/R phenotypes in subjects with different degrees of glucose intolerance.

METHODS

We examined 566 members of the Cohort study of Diabetes and Atherosclerosis Maastricht (CoDAM), including subjects with normal glucose tolerance (NGT, n = 298), impaired glucose regulation (IGR, n = 128), newly diagnosed Type 2 diabetes (nDM, n = 78) and treated, that is to say known, Type 2 diabetes (kDM, n = 64). PON1 activity was measured in serum using paraoxon and diazoxon as substrates. The PON1 phenotype was determined using two-dimensional enzyme analysis.

RESULTS

The RR-phenotype was significantly more frequent in nDM compared with NGT subjects (14.1 vs. 6.0%, P = 0.05). Adjusted for the PON1 phenotype, subjects with nDM had significant lower PON1 activity towards paraoxon and diazoxon than subjects with NGT. Adjusted odds ratios comparing the RR-variant with the QQ-variant were 2.17 [95% confidence interval (CI): 0.90-5.24] for impaired glucose tolerance, 2.84 (95% CI: 1.03-7.83) for nDM, 2.13 (95% CI; 0.61-7.42) for kDM and 2.65 (95% CI: 1.10-6.40) for total diabetes mellitus.

CONCLUSIONS

An aberrant PON1 phenotype distribution and PON1 activity were observed in early diabetes. In addition, the higher state of oxidative stress may affect the future development of complications.

[The prevalence of the metabolic syndrome in the Netherlands: increased risk of cardiovascular diseases and diabetes mellitus type 2 in one quarter of persons under 60]

OBJECTIVE

To estimate the prevalence of the metabolic syndrome in the Netherlands in two populations in the age category 28-59 years and to compare this with the prevalence of hypercholesterolaemia in these populations.

DESIGN

Descriptive.

METHOD

Data from two Dutch population based studies were used: the 'Monitoring risicofactoren en gezondheid Nederland' (MORGEN) study ['Monitoring risk factors and health in the Netherlands' study] (1993-1995) and the 'Prevention of renal and vascular end-stage disease' (PREVEND) study (1998-1999). Subjects were identified as having the metabolic syndrome when they had at least three of the following five criteria according to the guideline of the 'National cholesterol education programme', 'Adult treatment panel III' (NCEP-2001): hyperglycaemia, low HDL-cholesterol level, hypertriglyceridaemia, hypertension or abdominal obesity. Final estimates were weighed according to the age- and sex distribution of the Dutch population during these survey years based on figures of the Dutch Central Bureau of Statistics.

RESULTS

On average, the prevalence of the metabolic syndrome was 14%, 19% in men and 12% in women in the MORGEN study, and 16% and 10% in men and women in the PREVEND study. The prevalence in subjects below 40 was 12% for men and 5% for women. The prevalence increased considerably with age. Among subjects with both abdominal obesity and hypertension the prevalence was 68%. Among subjects with 'hypertriglyceridaemic waist' the prevalence was 94%. The prevalence of the metabolic syndrome showed little overlap with the prevalence of hypercholesterolaemia (> or = 6.5 mmol/l). In total, 26% of the subjects had either the metabolic syndrome or high total cholesterol levels.

CONCLUSION

Approximately 1 million Dutch adults below 60 years of age had the metabolic syndrome in the 1990's. Based on the total prevalence of the metabolic syndrome and hypercholesterolaemia, one quarter of the Dutch population younger then 60 runs an increased risk of cardiovascular disease and type 2 diabetes mellitus.

The Emerging Risk Factors Collaboration: analysis of individual data on lipid, inflammatory and other markers in over 1.1 million participants in 104 prospective studies of cardiovascular diseases

Many long-term prospective studies have reported on associations of cardiovascular diseases with circulating lipid markers and/or inflammatory markers. Studies have not, however, generally been designed to provide reliable estimates under different circumstances and to correct for within-person variability. The Emerging Risk Factors Collaboration has established a central database on over 1.1 million participants from 104 prospective population-based studies, in which subsets have information on lipid and inflammatory markers, other characteristics, as well as major cardiovascular morbidity and cause-specific mortality. Information on repeat measurements on relevant characteristics has been collected in approximately 340,000 participants to enable estimation of and correction for within-person variability. Re-analysis of individual data will yield up to approximately 69,000 incident fatal or nonfatal first ever major cardiovascular outcomes recorded during about 11.7 million person years at risk. The primary analyses will involve age-specific regression models in people without known baseline cardiovascular disease in relation to fatal or nonfatal first ever coronary heart disease outcomes. This initiative will characterize more precisely and in greater detail than has previously been possible the shape and strength of the age- and sex-specific associations of several lipid and inflammatory markers with incident coronary heart disease outcomes (and, secondarily, with other incident cardiovascular outcomes) under a wide range of circumstances. It will, therefore, help to determine to what extent such associations are independent from possible confounding factors and to what extent such markers (separately and in combination) provide incremental predictive value.

Genetic variation in thioredoxin interacting protein (TXNIP) is associated with hypertriglyceridaemia and blood pressure in diabetes mellitus

AIMS

Thioredoxin interacting protein (TXNIP) is an attractive candidate gene for diabetes or diabetic dyslipidaemia, since TXNIP is the strongest glucose-responsive gene in pancreatic B-cells, TXNIP deficiency in a mouse model is associated with hyperlipidaemia and TXNIP is located in the 1q21-1q23 chromosomal Type 2 diabetes mellitus (DM) locus. We set out to investigate whether metabolic effects of TXNIP that were previously reported in a murine model are also relevant in human Type 2 DM.

METHODS

The frequency distribution of a 3' UTR single nucleotide polymorphism (SNP) in TXNIP was investigated in subjects with normal glucose tolerance (NGT; n = 379), impaired glucose tolerance (IGT; n = 228) and Type 2 DM (n = 230). Metabolic data were used to determine the effect of this SNP on parameters associated with lipid and glucose metabolism.

RESULTS

The frequency of the TXNIP variation did not differ between groups, but within the group of diabetic subjects, carriers of the TXNIP-T variant had 1.6-fold higher triglyceride concentrations (P = 0.015; n = 136) and a 5.5-mmHg higher diastolic blood pressure (P = 0.02; n = 212) than homozygous carriers of the common C-allele, whereas in non-diabetic subjects fasting glucose was 0.26 mmol/l lower (P = 0.002; n = 478) in carriers of the T-allele. Moreover, a significant interaction between plasma glucose concentrations and TXNIP polymorphism on plasma triglycerides was observed (P = 0.012; n = 544).

CONCLUSION

This is the first report to implicate TXNIP in a human disorder of energy metabolism, Type 2 diabetes. The effect of TXNIP on triglycerides is influenced by plasma glucose concentrations, suggesting that the biological relevance of TXNIP variations may be particularly relevant in recurrent episodes of hyperglycaemia.

Improvements in glucose tolerance and insulin sensitivity after lifestyle intervention are related to changes in serum fatty acid profile and desaturase activities: the SLIM study

AIMS/HYPOTHESIS

The aim of this study was to investigate whether lifestyle intervention-induced changes in serum fatty acid profile of cholesteryl esters and estimated desaturase activities are related to improvements in insulin sensitivity in subjects at risk of type 2 diabetes.

MATERIALS AND METHODS

In the Study on Lifestyle Intervention and Impaired Glucose Tolerance Maastricht (SLIM), 97 men and women with IGT were randomised to a combined diet and exercise programme (47 intervention) or a control group (50 control subjects). At baseline and after 1 year the following assessments were made: an OGTT, an exercise test to determine maximal aerobic capacity, anthropometry, and analysis of the serum fatty acid profile of cholesteryl esters.

RESULTS

The lifestyle programme was effective in reducing the intake of total and saturated fat, increasing physical activity, reducing obesity and improving insulin sensitivity and glucose tolerance. Regression analysis of the total population showed that an increase in the C20:4 n-6/C20:3 n-6 ratio (estimated Delta5-desaturase activity) and reductions in the C18:3 n-6/C18:2 n-6 ratio (estimated Delta6-desaturase activity) and the C16:1 n-7/C16:0 ratio (estimated Delta9-desaturase activity or stearoyl-CoA desaturase-1) were significantly associated with a decrease in homeostasis model assessment for insulin resistance. After adjustment for lifestyle changes (change in percentage body fat, aerobic capacity and saturated fat intake), these associations were partly reduced, but remained statistically significant.

CONCLUSIONS/INTERPRETATION

Lifestyle-induced changes in fatty acid profile of cholesteryl esters and desaturase activities were independently related to changes in insulin sensitivity in subjects at risk of type 2 diabetes.

Direct association of a promoter polymorphism in the CD36/FAT fatty acid transporter gene with Type 2 diabetes mellitus and insulin resistance

AIMS

The membrane-bound fatty acid transporter CD36/FAT may play a role in disturbed fatty acid handling as observed in the metabolic syndrome and Type 2 diabetes mellitus (T2DM). Genetic variation in the CD36 gene may contribute to the aetiology of diabetes.

METHODS

A population-based cohort in the Netherlands [age > 40 years and body mass index (BMI) > 25 kg/m2] of 675 subjects was phenotyped with respect to glucose metabolism with an oral glucose tolerance test and was genotyped for a known 478C-->T substitution and a C/T snp in the upstream promoter region (rs1527479) in the CD36 gene.

RESULTS

T2DM was more prevalent in the TT genotype than in the CC genotype. This was most pronounced in women and in subjects with a high BMI (BMI > 27 kg/m2). In addition, within the group of diabetic patients, the TT genotype was commoner in subjects with increased homeostasis model assessment (HOMA) index for insulin resistance. The 478C-->T substitution, previously found in the Japanese population, was not found in our caucasian population.

CONCLUSIONS

This is the first study to show a direct association of a CD36 snp with T2DM. Moreover, within the diabetic subjects, this CD36 snp was associated with insulin resistance (HOMA index).

Plasma fibrinogen level and the risk of major cardiovascular diseases and nonvascular mortality: an individual participant meta-analysis

CONTEXT

Plasma fibrinogen levels may be associated with the risk of coronary heart disease (CHD) and stroke.

OBJECTIVE

To assess the relationships of fibrinogen levels with risk of major vascular and with risk of nonvascular outcomes based on individual participant data.

DATA SOURCES

Relevant studies were identified by computer-assisted searches, hand searches of reference lists, and personal communication with relevant investigators.

STUDY SELECTION

All identified prospective studies were included with information available on baseline fibrinogen levels and details of subsequent major vascular morbidity and/or cause-specific mortality during at least 1 year of follow-up. Studies were excluded if they recruited participants on the basis of having had a previous history of cardiovascular disease; participants with known preexisting CHD or stroke were excluded.

DATA EXTRACTION

Individual records were provided on each of 154,211 participants in 31 prospective studies. During 1.38 million person-years of follow-up, there were 6944 first nonfatal myocardial infarctions or stroke events and 13,210 deaths. Cause-specific mortality was generally available. Analyses involved proportional hazards modeling with adjustment for confounding by known cardiovascular risk factors and for regression dilution bias.

DATA SYNTHESIS

Within each age group considered (40-59, 60-69, and > or =70 years), there was an approximately log-linear association with usual fibrinogen level for the risk of any CHD, any stroke, other vascular (eg, non-CHD, nonstroke) mortality, and nonvascular mortality. There was no evidence of a threshold within the range of usual fibrinogen level studied at any age. The age- and sex- adjusted hazard ratio per 1-g/L increase in usual fibrinogen level for CHD was 2.42 (95% confidence interval [CI], 2.24-2.60); stroke, 2.06 (95% CI, 1.83-2.33); other vascular mortality, 2.76 (95% CI, 2.28-3.35); and nonvascular mortality, 2.03 (95% CI, 1.90-2.18). The hazard ratios for CHD and stroke were reduced to about 1.8 after further adjustment for measured values of several established vascular risk factors. In a subset of 7011 participants with available C-reactive protein values, the findings for CHD were essentially unchanged following additional adjustment for C-reactive protein. The associations of fibrinogen level with CHD or stroke did not differ substantially according to sex, smoking, blood pressure, blood lipid levels, or several features of study design.

CONCLUSIONS

In this large individual participant meta-analysis, moderately strong associations were found between usual plasma fibrinogen level and the risks of CHD, stroke, other vascular mortality, and nonvascular mortality in a wide range of circumstances in healthy middle-aged adults. Assessment of any causal relevance of elevated fibrinogen levels to disease requires additional research.

Common variants in the ATP-sensitive K+ channel genes KCNJ11 (Kir6.2) and ABCC8 (SUR1) in relation to glucose intolerance: population-based studies and meta-analyses

AIMS

To evaluate the relation between common variants in the ATP-sensitive K+ channel genes and glucose intolerance.

METHODS

We conducted a meta-analysis of reported association studies in Caucasian populations for common variants in the ABCC8 (exons 16 and 18) and the KCNJ11 (E23K) gene and examined sources of heterogeneity in the results. The meta-analysis was based on 7768-10216 subjects (depending on the gene variant), and included two new population-based studies in the Netherlands with 725 cases and 742 controls.

RESULTS

For the KCNJ11 variant, the summary odds ratio (OR) for glucose intolerance was 1.12 (1.01-1.23, P=0.03) for the EK genotype and 1.44 (1.17-1.78, P=0.0007) for the KK genotype, as compared with the EE genotype. For the ABCC8 exon 16 variant, the OR was 1.06 (0.94-1.19, P=0.34) for ct and 0.93 (0.71-1.20, P=0.56) for tt, as compared with the cc genotype. For ABCC8 exon 18, the OR was 1.20 (0.97-1.49, P=0.10) for CT/TT, as compared with the CC genotype. Studies of the ABCC8 variants that were published first or had smaller sample sizes (for the exon 18 variant) showed stronger associations, which may indicate publication bias. For the ABCC8 exon 18 and the KCNJ11 variant, associations were stronger for studies of clinical diabetes than newly detected glucose intolerance. The population attributable risk for clinical Type 2 diabetes was 6.2% for the KCNJ11 KK genotype and 10.1% for the KCNJ11 EK and KK genotype combined.

CONCLUSIONS

The common KCNJ11 E23K gene variant, but not the ABCC8 exon 16 or exon 18 variant, was consistently associated with Type 2 diabetes.

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

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'.

Physical activity and stroke. A meta-analysis of observational data

BACKGROUND

Based on studies published so far, the protective effect of physical activity on stroke remains controversial. Specifically, there is a lack of insight into the sources of heterogeneity between studies.

METHODS

Meta-analysis of observational studies was used to quantify the relationship between physical activity and stroke and to explore sources of heterogeneity. In total, 31 relevant publications were included. Risk estimates and study characteristics were extracted from original studies and converted to a standard format for use in a central database.

RESULTS

Moderately intense physical activity compared with inactivity, showed a protective effect on total stroke for both occupational (RR = 0.64, 95% CI: 0.48-0.87) and leisure time physical activity (RR = 0.85, 95% CI: 0.78-0.93). High level occupational physical activity protected against ischaemic stroke compared with both moderate (RR = 0.77, 95% CI: 0.60-0.98) and inactive occupational levels (RR = 0.57, 95% CI: 0.43-0.77). High level compared with low level leisure time physical activity protected against total stroke (RR = 0.78, 95% CI: 0.71-0.85), haemorrhagic stroke (RR = 0.74, 95% CI: 0.57-0.96) as well as ischaemic stroke (RR = 0.79, 95% CI: 0.69-0.91). Studies conducted in Europe showed a stronger protective effect (RR = 0.47, 95% CI: 0.33-0.66) than studies conducted in the US (RR = 0.82, 95% CI: 0.75-0.90).

CONCLUSIONS

Lack of physical activity is a modifiable risk factor for both total stroke and stroke subtypes. Moderately intense physical activity is sufficient to achieve risk reduction.

The insulin receptor substrate-1 Gly972Arg polymorphism is not associated with Type 2 diabetes mellitus in two population-based studies

AIMS

The insulin receptor substrate-1 (IRS-1) gene is among the most frequently studied candidate genes for Type 2 diabetes, but findings have been inconsistent. This may have been due to generally small study sizes, or to interaction with body fatness as suggested by studies of insulin sensitivity. The aim of this study was to test the hypothesis that the IRS-1 Gly972Arg variant increases risk of Type 2 diabetes.

METHODS

We conducted two large population-based studies including a total of 725 cases and 742 control subjects, who were Caucasian Dutch men and women aged 40-70 years. We calculated odds ratios adjusted for body mass index, study centre, sex and age.

RESULTS

Carriers of the Arg allele did not have a higher prevalence of newly detected (OR 0.49, 95% CI 0.24-1.01) or treated (OR 0.71, 0.37-1.35) Type 2 diabetes in the first study, or a higher prevalence of glucose intolerance (OR 1.07, 0.71-1.59) in the second study. The summary odds ratio was 0.86 (0.62-1.17) for carrying the Arg allele as compared with the Gly/Gly genotype. Associations did not differ appreciably by degree of obesity. Also, the Arg variant was not associated with detrimental values for body mass index, waist circumference, plasma HDL-and total cholesterol or hypertension.

CONCLUSIONS

Our findings indicate that the IRS-1 Gly972Arg variant does not substantially increase risk of common Type 2 diabetes, or Type 2 diabetes in obese persons.

[Nutrition and health--unclear association between intake of vitamin E and the risk of coronary heart disease]

Vitamin E is a fat-soluble antioxidant and is possibly involved in the prevention of coronary heart disease by inhibiting oxidative modification of LDL cholesterol. The results of studies on the association between vitamin-E intake and coronary heart disease are inconsistent in observational studies and absent in large-scale intervention studies. This may be the consequence of confounding in observational studies and imperfections in the design of intervention trials. Another explanation is that vitamin E may only function protectively in the presence of sufficient co-antioxidants. At present, there is no evidence that vitamin E lowers the risk of coronary heart disease.

Subscapular skinfold thickness distinguishes between transient and persistent impaired glucose tolerance: Study on Lifestyle-Intervention and Impaired Glucose Tolerance Maastricht (SLIM)

AIMS

To assess whether adding anthropometric measurements to an oral glucose tolerance test (OGTT) can help to distinguish between transient and persistent impaired glucose tolerance (IGT).

METHODS

From the SLIM project (Study on Lifestyle-Intervention and IGT Maastricht), a study designed to evaluate whether diet and physical activity intervention can improve glucose tolerance in subjects at risk for diabetes, 108 subjects with IGT underwent a repeated OGTT 2-4 months after the initial OGTT. Following the second test, subjects were classified as transient IGT, or persistent IGT. Anthropometric measurements, including body mass index, waist and hip circumference, sagittal and transverse abdominal diameters and skinfold thickness measurements, were done during the second OGTT.

RESULTS

Persistent IGT was diagnosed in 47 subjects (44%), transient IGT in 40 (37%), impaired fasting glucose in eight subjects (7%), and diabetes in 13 cases (12%). Two-hour blood glucose levels at the initial OGTT and subscapular skinfold thickness were significantly higher in subjects with persistent IGT (2-h blood glucose 9.8+/-0.1 mmol/l vs. 10.2+/-0.1 mmol/l for transient IGT and persistent IGT, respectively; subscapular skinfold thickness 25.4+/-1.4 mm vs. 29.8+/-1.2 mm for transient IGT and persistent IGT, respectively). After adjustment for age, sex and family history of diabetes mellitus, logistic regression indicated that 2-h blood glucose level during the initial OGTT represented the strongest predictor of persistent IGT (P<0.02), followed by subscapular skinfold thickness (P<0.05). After adjustment for 2-h blood glucose levels during the first OGTT, subscapular skinfold thickness remained significantly associated with persistent IGT (odds ratio 1.84; P<0.05).

CONCLUSIONS

In addition to the 2-h blood glucose level, subscapular skinfold thickness was the best predictor of persistent IGT, suggesting that adding simple anthropometric measures to oral glucose tolerance testing may improve the distinction between persistent and transient glucose intolerance.

Gly972Arg variant in the insulin receptor substrate-1 gene and association with Type 2 diabetes: a meta-analysis of 27 studies

AIMS/HYPOTHESIS

Several case-control studies have examined the association between the Gly972Arg variant in the IRS-1 gene and Type 2 diabetes, but most had limited power and results could therefore be conflicting.

METHODS

We systematically reviewed the literature by means of a meta-analysis and investigated sources of heterogeneity in results of different studies.

RESULTS

The summary risk ratio, based on 3408 cases and 5419 control cases from 27 studies, was 1.25 (95% CI 1.05-1.48). The results, however, differed according to the type of study, method of verifying non-diabetic status of the control subjects, and age of the case subjects. Population-based studies reported lower odds ratios than hospital-based studies (OR 0.98, 95% CI 0.74-1.30 vs OR 1.43, 95% CI 1.17-1.74). Also, the diagnostic test to exclude diabetes amongst control subjects interacted with the association between the IRS-1 Gly972Arg variant and Type 2 diabetes (p=0.03). Finally, the odds ratio reduced with increasing age ( p=0.03).

CONCLUSION/INTERPRETATION

Overall, carriers of the 972Arg variant of the IRS-1 gene are at a 25% increased risk of having Type 2 diabetes compared with non-carriers. The odds ratios are generally higher in hospital-based studies, including relatively young, symptomatic, cases.