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Heiner Boeing

Publications and source records attributed to Heiner Boeing.

At least 91 records · Page 5Linked to original sources
PubMed2004

Association of nut and seed intake with colorectal cancer risk in the European Prospective Investigation into Cancer and Nutrition.

A link between unsaturated fatty acids or phytonutrients and reduced risk of colorectal cancer has been suggested. However, the effects of higher intake of dietary sources of these nutrients, such as the nuts and seeds food group, are less clear. The objective of this study was to determine the effects of nut and seed intake on colorectal cancer risk within the European Prospective Investigation into Cancer and Nutrition study, a large prospective cohort study involving 10 European countries. Total nut and seed intake was determined from country-specific dietary questionnaires. The data set included 478,040 subjects (141,988 men, 336,052 women) with a total of 855 (327 men, 528 women) colon and 474 (215 men, 259 women) rectal cancer cases. A multivariate Cox proportional hazards model, stratified by center and controlled for fruit intake, dietary fiber, energy, height, weight, sex, age, physical activity, and smoking, was used. The data show no association between higher intake of nuts and seeds and risk of colorectal, colon, and rectal cancers in men and women combined, but a significant inverse association was observed in subgroup analyses for colon cancer in women at the highest (>6.2 g/d) versus the lowest (nonconsumers; hazard ratio, 0.69; 95% confidence interval, 0.50-0.95) category of intake and for the linear effect of log-transformed intake (hazard ratio, 0.89; 95% confidence interval, 0.80-0.98), with no associations in men. It is not evident from this data why there may be a stronger association in women or why it may be limited to the colon, suggesting that much further research is necessary.

Adult↗
PubMed2003

Smoking and the risk of gastric cancer in the European Prospective Investigation Into Cancer and Nutrition (EPIC).

Smoking has recently been recognised as causally associated with the development of gastric cancer (GC). However, evidence on the effect by sex, duration and intensity of smoking, anatomic subsite and cessation of smoking is limited. Our objective was to assess the relation between tobacco use and GC incidence in the European Prospective Investigation into Cancer and Nutrition (EPIC). We studied data from 521,468 individuals recruited from 10 European countries taking part in the EPIC study. Participants completed lifestyle questionnaires that included questions on lifetime consumption of tobacco and diet in 1991-1998. Participants were followed until September 2002, and during that period 305 cases of stomach cancer were identified. After exclusions, 274 were eligible for the analysis, using the Cox proportional hazard model. After adjustment for educational level, consumption of fresh fruit, vegetables and preserved meat, alcohol intake and body mass index (BMI), there was a significant association between cigarette smoking and gastric cancer risk: the hazard ratio (HR) for ever smokers was 1.45 (95% confidence interval [CI] = 1.08-1.94). The HR of current cigarette smoking was 1.73 (95% CI = 1.06-2.83) in males and 1.87 (95% CI = 1.12-3.12) in females. Hazard ratios increased with intensity and duration of cigarette smoked. A significant decrease of risk was observed after 10 years of quitting smoking. A preliminary analysis of 121 cases with identified anatomic site showed that current cigarette smokers had a higher HR of GC in the cardia (HR = 4.10) than in the distal part of the stomach (HR = 1.94). In this cohort, 17.6 % (95% CI = 10.5-29.5 %) of GC cases may be attributable to smoking. Findings from this large study support the causal relation between smoking and gastric cancer in this European population. Stomach cancer should be added to the burden of diseases caused by smoking.

Adult↗
PubMed2003

Risk of hypertension among women in the EPIC-Potsdam Study: comparison of relative risk estimates for exploratory and hypothesis-oriented dietary patterns.

Analysis of dietary patterns is considered a useful approach to the examination of diet-disease associations. This study examined the risk of incident hypertension associated with dietary patterns in 8,552 women in the EPIC (European Prospective Investigation into Cancer and Nutrition)-Potsdam Study. The baseline examination was carried out between 1994 and 1998. During 2-4 years of follow-up (through May 15, 2002), 123 incident hypertension cases were verified by medical records. Two exploratory dietary patterns, a "traditional cooking" pattern (meat, cooked vegetables, sauce, potatoes, and poultry) and a "fruits and vegetables" pattern (fruits, raw vegetables, and vegetable oil), were identified by exploratory factor analysis and confirmed by confirmatory factor analysis. Additionally, a hypothesis-oriented pattern based on the Dietary Approaches to Stop Hypertension (DASH) Study was defined (fruits, vegetables, and milk products). Patterns' associations with disease risk were estimated by Cox regression. While no significant associations were observed for the traditional cooking pattern or the fruits and vegetables pattern after adjustment for potential confounders, women in the third quartile of the DASH pattern were at lower risk than women in the lowest quartile (hazard rate ratio = 0.51, 95% confidence interval: 0.29, 0.89). These results suggest that this hypothesis-oriented pattern might play an important role in the risk of hypertension.

Adult↗
PubMed2003

Dietary fibre in food and protection against colorectal cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC): an observational study.

BACKGROUND: Dietary fibre is thought to protect against colorectal cancer but this view has been challenged by recent prospective and intervention studies that showed no protective effect. METHODS: We prospectively examined the association between dietary fibre intake and incidence of colorectal cancer in 519978 individuals aged 25-70 years taking part in the EPIC study, recruited from ten European countries. Participants completed a dietary questionnaire in 1992-98 and were followed up for cancer incidence. Relative risk estimates were obtained from fibre intake, categorised by sex-specific, cohort-wide quintiles, and from linear models relating the hazard ratio to fibre intake expressed as a continuous variable. FINDINGS: Follow-up consisted of 1939011 person-years, and data for 1065 reported cases of colorectal cancer were included in the analysis. Dietary fibre in foods was inversely related to incidence of large bowel cancer (adjusted relative risk 0.75 [95% CI 0.59-0.95] for the highest versus lowest quintile of intake), the protective effect being greatest for the left side of the colon, and least for the rectum. After calibration with more detailed dietary data, the adjusted relative risk for the highest versus lowest quintile of fibre from food intake was 0.58 (0.41-0.85). No food source of fibre was significantly more protective than others, and non-food supplement sources of fibre were not investigated. INTERPRETATION: In populations with low average intake of dietary fibre, an approximate doubling of total fibre intake from foods could reduce the risk of colorectal cancer by 40%.

Adult↗
PubMed2003

Adiponectin and protection against type 2 diabetes mellitus.

Adiponectin is an adipocyte-derived peptide, which has anti-inflammatory and insulin-sensitising properties. We designed a nested case-control study to assess whether baseline adiponectin concentrations in plasma are independently associated with risk of type 2 diabetes. We found that adiponectin concentrations in plasma were lower among individuals who later developed type 2 diabetes than among controls (mean 5.34 microg/mL [SD 3.49] vs 6.87 microg/mL [4.58], p<0.0001). High concentrations of adiponectin were associated with a substantially reduced relative risk of type 2 diabetes after adjustment for age, sex, waist-to-hip ratio, body-mass index, smoking, exercise, alcohol consumption, education, and glycosylated haemoglobin A(1c) (odds ratio 4th vs 1st quartile 0.3 [95% CI 0.2-0.7], p=0.0051). We conclude that adiponectin is independently associated with a reduced risk of type 2 diabetes in apparently healthy individuals.

Adiponectin↗
PubMed2003

Trends in cigarette smoking in the German centers of the European Prospective Investigation into Cancer and Nutrition (EPIC): the influence of the educational level.

BACKGROUND: Several studies in Germany and other European countries have already shown smoking prevalence to be related to education. This study was aimed to investigate time trends in smoking habits in the German cohorts Heidelberg and Potsdam of the European Prospective Investigation into Cancer and Nutrition (EPIC) according to sex, birth cohort, and level of education. METHODS: Within EPIC, 25,546 and 27,548 participants were recruited in Heidelberg and Potsdam, respectively. Data on smoking were collected by means of a computer-guided interview during the baseline examination between 1994 and 1998. For each birth cohort smoking prevalence and mean number of cigarettes smoked per day at different ages were calculated. Odds ratios and 95% confidence interval for associations between smoking prevalence and educational level were computed by using logistic regression. RESULTS: Smoking prevalence was higher among men than among women, with a smaller difference in younger birth cohorts. Between 1950 and 1960, smoking prevalence among women in the Heidelberg cohort rose sharply (from 12.8% to 51.8% in the least educated group). This strong increase was delayed by 10 years in the Potsdam cohort. Men and women in Heidelberg smoked more cigarettes per day than their counterparts in Potsdam, but in both study centers less educated subjects smoked more than subjects with a higher education. CONCLUSIONS: Smoking patterns in the Potsdam and Heidelberg cohorts are quite similar with respect to prevalence and years of lifetime smoking. Since an increasing difference between smoking prevalence of less and high educated individuals is observable, programs on smoking cessation should especially concentrate on persons of lower educational level.

Adult↗
PubMed2003

Relation among alcohol dehydrogenase 2 polymorphism, alcohol consumption, and levels of gamma-glutamyltransferase.

In human beings, alcohol is metabolized primarily by alcohol dehydrogenase 2 (ADH2) and acetaldehyde dehydrogenase 2 (ALDH2). Whereas polymorphisms of the ALDH2 are common in Asian persons, polymorphisms of the ADH2 seem to be more important in Caucasian individuals. The aim of this study was to assess the relation among ADH2 polymorphism, alcohol consumption, and levels of gamma-glutamyltransferase (GGT). The question was examined among 1,663 subjects (736 men and 927 women) participating in a national representative health and nutrition survey (VERA substudy of the German National Nutrition Survey). Alcohol consumption was assessed through responses to a semiquantitative food frequency questionnaire (FFQ), and the ADH2 restriction fragment length polymorphism (RFLP) Mae III and GGT levels were analyzed from frozen serum samples. The relations between the polymorphism and alcohol consumption and between alcohol consumption and GGT levels according to the polymorphism were assessed with the use of descriptive statistics and contingency table analysis. Of the subjects studied, 2.8% were homozygous or heterozygous for the ADH2*2 allele, and high levels of alcohol consumption (>20 g/day) were less common among these subjects (8.5%) than among subjects with the ADH2*1 allele (19.9%). Median levels of GGT increased with increasing levels of alcohol consumption. This increase tended to be stronger among subjects with the ADH2*2 allele than among other subjects, although differences were not statistically significant (P value for interaction=.1) given the small number of subjects with the polymorphism. These results are consistent with the hypothesis that subjects with the ADH2*2 allele, on the one hand, might tend to drink less alcohol but, on the other hand, might be at increased risk of alcohol-related effects on the liver with consumption of larger amounts of alcohol. However, this hypothesis needs to be evaluated among larger population samples.

Adult↗
PubMed2003

An approach to construct simplified measures of dietary patterns from exploratory factor analysis.

Exploratory factor analysis might work well in elucidating the major dietary patterns prevailing in specific study populations. However, patterns extracted in one study population and their associations with disease risk cannot be reproduced with this data-specific method in other study populations. To construct less population-dependent pattern variables of similar content as original exploratory patterns, we proposed to derive so-called simplified pattern variables. They represent the sum of the unweighted standardised food variables which loaded high at the pattern of interest. Data from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study suggest that these simplified pattern variables might adequately approximate factor analysis-based dietary patterns. A simplified pattern variable based on the six highest loading food variables showed a correlation >0.95 with the originally derived factor score, which consisted of forty-seven food variables. Moreover, simplified pattern variables might adequately approximate patterns across different study populations. A simplified pattern variable showed similar factor loadings, ranging from 0.34 to 0.52, as well as similar associations with nutrient intake as a 'western' pattern originally reported from an US study population. These simplified pattern variables can subsequently be used to study pattern associations with disease risk, especially in multi-centre studies. It is therefore an approach that might overcome one of the most frequently claimed limitations of factor analyses applied in epidemiology: their non-comparable risk estimates.

Diet↗
PubMed2003

Evaluating the potential health gain of the World Health Organization's recommendation concerning vegetable and fruit consumption.

OBJECTIVE: The World Health Organization (WHO) recommends a daily intake of at least 400 g of vegetables and fruit. The aim of this paper was to evaluate the public health benefit of meeting this WHO recommendation by applying a statistical method that combines estimated intake distributions and simulated intake changes. DESIGN AND SETTING: The benefit of an increased consumption of vegetables and fruit was quantified by the preventable proportion of diseases. This proportion was estimated by a general formula derived in the paper that incorporates individual relative risks. Three different strategies of increasing usual intake were simulated and compared. The first strategy assumes that all individuals increase their intake by the same amount, the second assumes a constant increase among low consumers, and the third simulates individual increments necessary to meet the WHO recommendation. Calculations were made for three different scenarios with varying relative risks. RESULTS: The third simulation strategy turned out to be the most appropriate one to quantify the potential health gain of the current dietary recommendation. Applying this strategy to prevent cancer, the proportion of preventable cases was country-specific. Estimates for France and Sweden were 21.9% and 19.3%, respectively, which are somewhat lower than the non-specific figure published by the World Cancer Research Fund. CONCLUSIONS: To improve estimates of the preventable proportion of diseases, the estimation formula presented here can be applied. Its application requires intake data to estimate the initial intake distribution in the population and to simulate adequate dietary changes.

Diet Surveys↗
PubMed2003

Portion size adds limited information on variance in food intake of participants in the EPIC-Potsdam study.

Food-frequency questionnaire (FFQ) data should reflect interindividual variation and therefore measure variance in intake among populations. We conducted this analysis to evaluate the relevance of separate portion size questions to the interindividual variation in food intake. The contribution of portion size questions to the variance in food intake was quantified and compared with the variance when group-specific portion sizes would be assigned, using 26,764 FFQ of the European Investigation into Cancer and Nutrition (EPIC)-Potsdam Study. Groups were defined according to gender, age (<50 y, >/=50 y) or body mass index (BMI) (<26 kg/m(2), >/=26 kg/m(2)). The FFQ inquired about both consumption frequency and portion size. Linear regression models for each food item were fit with intake (g/d) as dependent variables and frequency of intake as independent variables. The mean coefficient of determination (R(2)) for the different food items explained by frequency only was 84.0% (71.2-95.7%). The R(2) for gender-, age- and BMI-specific frequencies of intake did not markedly alter the overall results. We conclude that the omission of individual portion size information would probably result in a notable reduction of interindividual variance. However, to reduce the respondents' burden and to increase data completeness in self-administration in large epidemiologic studies, the assignment of a constant portion size seems to be adequate. The variance was not increased markedly when constant gender-, age- and BMI-specific portion sizes were applied, thus supporting the assignment of an overall portion size.

Age Distribution↗
PubMed2003

Quantity and quality of dietary fat, carbohydrate, and fiber intake in the German EPIC cohorts.

AIM: This evaluation aims to describe the quantity and quality of dietary fat, carbohydrate and fiber intake in both German cohorts participating in the European Prospective Investigation into Cancer and Nutrition (EPIC). METHODS: Estimates are based on standardized computer-guided 24-hour dietary recalls from 1,078 women and 1,013 men in Heidelberg and 898 women and 1,032 men in Potsdam. In a subsample, plasma phospholipid (PL) fatty acids were analyzed as well. RESULTS: Adjusted mean dietary intake estimates demonstrated that the contribution of fat as well as n-6 and n-3 polyunsaturated fatty acids (PUFA) to the total daily energy intake was higher in both women and men of EPIC-Potsdam compared to EPIC-Heidelberg. Surprisingly, the dietary n-6/n-3 PUFA ratio was lower in the Potsdam cohort. These results were confirmed by means of the PL fatty acid pattern. Besides the higher contribution of polysaccharides to total energy intake in EPIC-Heidelberg, women of the Heidelberg cohort revealed a significantly lower contribution of mono- and disaccharides (sucrose) to total energy intake. Although total fiber intake data were similar in both cohorts, analysis by food groups showed differences in dietary fiber intake originating from the food groups cereals, fruits and potatoes. CONCLUSION: The results demonstrate distinct differences in the dietary fat, carbohydrate and fiber intake between both German EPIC cohorts, which contribute to the exposure variation in the whole of EPIC.

Adult↗
PubMed2003

Inflammatory cytokines and the risk to develop type 2 diabetes: results of the prospective population-based European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam Study.

A subclinical inflammatory reaction has been shown to precede the onset of type 2 (non-insulin-dependent) diabetes. We therefore examined prospectively the effects of the central inflammatory cytokines interleukin (IL)-1beta, IL-6, and tumor necrosis factor-alpha (TNF-alpha) on the development of type 2 diabetes. We designed a nested case-control study within the prospective population-based European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study including 27,548 individuals. Case subjects were defined to be those who were free of type 2 diabetes at baseline and subsequently developed type 2 diabetes during a 2.3-year follow-up period. A total of 192 cases of incident type 2 diabetes were identified and matched with 384 non-disease-developing control subjects. IL-6 and TNF-alpha levels were found to be elevated in participants with incident type 2 diabetes, whereas IL-1beta plasma levels did not differ between the groups. Analysis of single cytokines revealed IL-6 as an independent predictor of type 2 diabetes after adjustment for age, sex, BMI, waist-to-hip ratio (WHR), sports, smoking status, educational attainment, alcohol consumption, and HbA(1c) (4th vs. the 1st quartile: odds ratio [OR] 2.6, 95% CI 1.2-5.5). The association between TNF-alpha and future type 2 diabetes was no longer significant after adjustment for BMI or WHR. Interestingly, combined analysis of the cytokines revealed a significant interaction between IL-1beta and IL-6. In the fully adjusted model, participants with detectable levels of IL-1beta and elevated levels of IL-6 had an independently increased risk to develop type 2 diabetes (3.3, 1.7-6.8), whereas individuals with increased concentrations of IL-6 but undetectable levels of IL-1beta had no significantly increased risk, both compared with the low-level reference group. These results were confirmed in an analysis including only individuals with HbA(1c) <5.8% at baseline. Our data suggest that the pattern of circulating inflammatory cytokines modifies the risk for type 2 diabetes. In particular, a combined elevation of IL-1beta and IL-6, rather than the isolated elevation of IL-6 alone, independently increases the risk of type 2 diabetes. These data strongly support the hypothesis that a subclinical inflammatory reaction has a role in the pathogenesis of type 2 diabetes.

Adult↗
PubMed2003

Group level validation of protein intakes estimated by 24-hour diet recall and dietary questionnaires against 24-hour urinary nitrogen in the European Prospective Investigation into Cancer and Nutrition (EPIC) calibration study.

A calibration approach was developed to correct for systematic between-cohort dietary measurement errors in the European Prospective Investigation into Cancer and Nutrition (EPIC), a large multicenter cohort study. To validate the 24-h diet recalls (24-HDRs) as reference measurements for between-cohort calibration, we estimated the agreement between center mean nitrogen (N) and total energy intakes and mean 24-h urinary N. Similar analyses using N and energy intake data from different dietary questionnaires (DQs) used at study baseline were conducted to estimate the effect of the calibration approach. This study was conducted between 1995 and 1999, and involved 1103 volunteers of both genders from 12 centers participating in European Prospective Investigation into Cancer and Nutrition. Pearson's correlation coefficients were weighted for study center sample size. When both genders were considered together (n = 22), the correlation coefficients between the center mean log-transformed urinary estimates and the center mean log-transformed dietary N estimates from the 24-HDRs were 0.86 and 0.94 after exclusion of outliers. The corresponding correlation with the DQs was 0.53. When center mean total energy intakes were regressed on center mean urinary N, the correlation remained slightly higher with 24-HDRs (0.91; 0.95 after exclusion of outliers) than DQs (0.86). When stratified by gender, these correlations were systematically higher in men than women with both dietary methods. The beta regression coefficients were not significantly different from 1 when mean N (or total energy intakes) from 24-HDR or DQ were regressed on urinary estimates, except with N from 24-HDRs in men and, in most cases, after adjustment for age, body mass index, and sex with both genders together. This suggests that overall the systematic bias across centers is of uniform magnitude. Although relatively high correlations were observed between urinary N and both dietary methods in men, the errors in DQs tend to vary in both directions (under- and over-reporting) in contrast with 24-HDRs in women. This observation may have implications on the dietary measurement error characteristics and support the potential benefit of between-cohort calibration.

Calibration↗
PubMed2002

Standardization of dietary intake measurements by nonlinear calibration using short-term reference data.

Statistical analysis of pooled dietary intake data in multicenter and multiethnic studies is often hampered by lack of comparability due to application of different food frequency questionnaires (FFQs). To remove this deficiency, dietary intake measurements should be standardized. This paper presents a standardization procedure based on nonlinear calibration, which aims to approximate the usual intake distribution estimated by reference measurements. The method can be applied in studies with repeated standardized reference measurements that can refer to time periods different from that of the FFQ. It was developed especially for short-term reference assessment methods, such as 24-hour recalls, diet records, and biomarkers. Similar to linear calibration, the proposed method does not change the rankings of subjects in each center or group; therefore, it maintains the within-center validity of the FFQ data. In contrast to linear calibration, the mixture of nonlinearly calibrated intake measurements from different centers or groups corresponds to the mixture of usual intake expected from the reference measurements. This paper illustrates this property of achieving high between-center validity by using macronutrient intake data from the 1995-1996 European Prospective Investigation into Cancer and Nutrition-Potsdam validation study. Here, the proposed method is compared with three linear calibration methods.

Calibration↗
PubMed2002

Behavioral changes in observational and intervention studies.

Changes of diet and other lifestyle factors are often highly recommended, but evidence for the effectiveness of behavioral changes in adult lives is limited. In the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam study, we investigated the reasons for and the direction of dietary changes as well as factors that are associated with the self-report of a change in diet. About 47% of the 27,548 cohort members reported a dietary change within the first 2 y of the follow-up. Detailed analysis of the type of change showed that public health recommendations are clearly understood. More vegetables and fruit and less fat are the most reported changes. Investigations into the reasons for dietary changes showed that in most instances and in ever shorter intervals, dietary recommendations resulting from progress in science are reinforced or partly modified. The health-conscious individuals in a population try to put these health messages into practice by modifying their behavior; these are the individuals who are particularly attracted to participate in scientifically oriented prospective studies and therefore are likely to be recruited by and retained in these studies. Behavioral changes over time may indicate dietary changes that are related to health and weight problems. The consideration of dietary changes during prospective data collection, therefore, is an important issue in the design and analysis of longitudinal studies-both cohort and intervention studies. Cohort studies in which dietary changes are adequately measured can contribute substantially to the evidence for health benefits resulting from changes in diet.

Adult↗
PubMed2002

Food groups as predictors for short-term weight changes in men and women of the EPIC-Potsdam cohort.

This study examined the effect of food group intake on subsequent 2-y weight change. Food-frequency questionnaire-based food intake data of 17,369 nonsmoking subjects of the European Prospective Investigation into Cancer and Nutrition (EPIC)-Potsdam cohort were examined in their relation to a subsequent weight change. Dietary data, collected from 1994 to 1998, were grouped into 24 food groups. Weight change per year follow-up was the outcome of interest; large weight gain was defined as > or =2 kg; small weight gain as > or =1 kg to <2 kg; large weight loss as < or = -2 kg; small weight loss as < or = -1 kg to > -2 kg and weight maintenance as +/- 1 kg. For each food group, a separate polytomous logistic regression model with stable weight as the reference group was constructed, controlling for age, body mass index, previous weight change, and behavioral and lifestyle factors. Odds ratios (OR) and 95% confidence intervals (CI) estimated the increase in risk associated with each 100 g/d increment in food group intake. In women, consumption of high energy, high fat food groups significantly predicted large weight gain, e.g., fats (OR = 1.75; 95% CI, 1.01-3.06), sauces (OR = 2.12; 95% CI, 1.17-3.82) and meat (OR = 1.36; 95% CI, 1.04-1.79), and the consumption of cereals predicted large weight loss (OR = 1.43; 95% CI, 1.09-1.88). In men, intake of high energy, high sugar foods, i.e., sweets, was significantly predictive of large weight gain (OR = 1.48; 95% CI, 1.03-2.13). Our data show that a diet rich in high fat and high energy foods predicts short-term weight gain even if controlled for many potential confounding factors.

Adult↗
PubMed2002

The effect of differences in measurement procedure on the comparability of blood pressure estimates in multi-centre studies.

The procedures for obtaining blood pressure measurements, and their quality of performance, should be similar between epidemiological studies to allow a valid comparison of blood pressure distribution and prevalence of hypertension between study populations. However, considerable methodological variation currently exists as there are several international guidelines on blood pressure measurement and a standard method of measurement has not yet been agreed. This paper reviews the literature in order quantitatively to define systematic differences between blood pressure measurements resulting from differences in arm used, body position, number of measurements, verbal communication, cuff size applied and measuring device used. The results were applied to differences in procedure between European Prospective Investigation into Cancer and Nutrition (EPIC) study centres, showing that blood pressure measurements may systematically differ between centres by as much as 10 mmHg for procedural reasons alone. For most reviewed methodological differences, it was possible to at least estimate a range of systematic error. There are, however, additional possible causes of systematic variation, for example arm position, postprandial hypotension and diurnal blood pressure variation, that could not be taken into account. It may be possible to make only a partial correction for the systematic inter-centre variation of the EPIC blood pressure measurements. This study highlights the importance of standardized protocols for blood pressure measurements in epidemiological studies.

Blood Pressure↗