Clustering of dietary variables and other lifestyle factors (Dutch Nutritional Surveillance System)

Clustering of Mediterranean dietary patterns linked with health-related quality of life in adolescents: the EHDLA study

The aim of this cross-sectional study was to analyze the association between adherence to the Mediterranean diet (MedDiet) and its dietary components and health-related quality of life (HRQoL) in a sample of Spanish adolescents. A total sample of 634 adolescents was included (mean age: 13.96 ± 1.54 years; 56.9% girls). The Mediterranean Diet Quality Index in children and adolescents (KIDMED) and the KIDSCREEN-10 were used to assess adherence to the MedDiet and its components and HRQoL, respectively. Linear regression was applied to estimate the association between overall adherence to the MedDiet and HRQoL. Cluster analysis was used to establish subgroups according to different patterns of MedDiet component consumption. Higher overall adherence to the MedDiet was significantly associated with greater HRQoL (unstandardized beta coefficient [β] = 0.329; 95% CI: 0.108, 0.550; p = 0.004), even after adjustment for sociodemographic, physical and lifestyle covariates (β = 0.228; 95% CI: 0.007, 0.449; p = 0.043). When different clusters were established according to similar features of MedDiet component consumption, the cluster with a higher percentage of individuals who skipped breakfast had significantly lower scores on the HRQoL scale (p < 0.05)  Conclusions: Our findings highlight the relevance of considering the specific patterns of food group consumption and MedDiet-related behaviors and not just the overall measure of MedDiet adherence for promoting HRQoL in adolescents. What is Known: • Previous studies have shown that some lifestyle behaviors, such as dietary habits, could be associated with health-related quality of life. • According to our results, higher adherence to the Mediterranean diet pattern was associated with greater health-related quality of life in adolescents. What is New: • Skipping breakfast seems to have a crucial role in health-related quality of life among adolescents. • These results could lead to the development of more specific dietary strategies for increasing health-related quality of life in adolescents.

A hybrid data mining model for diagnosis of patients with clinical suspicion of dementia

BACKGROUND AND OBJECTIVE

Given the phenomenon of aging population, dementias arise as a complex health problem throughout the world. Several methods of machine learning have been applied to the task of predicting dementias. Given its diagnostic complexity, the great challenge lies in distinguishing patients with some type of dementia from healthy people. Particularly in the early stages, the diagnosis positively impacts the quality of life of both the patient and the family. This work presents a hybrid data mining model, involving the mining of texts integrated to the mining of structured data. This model aims to assist specialists in the diagnosis of patients with clinical suspicion of dementia.

METHODS

The experiments were conducted from a set of 605 medical records with 19 different attributes about patients with cognitive decline reports. Firstly, a new structured attribute was created from a text mining process. It was the result of clustering the patient's pathological history information stored in an unstructured textual attribute. Classification algorithms (naïve bayes, bayesian belief networks and decision trees) were applied to obtain Alzheimer's disease and mild cognitive impairment predictive models. Ensemble methods (Bagging, Boosting and Random Forests) were used in order to improve the accuracy of the generated models. These methods were applied in two datasets: one containing only the original structured data; the other containing the original structured data with the inclusion of the new attribute resulting from the text mining (hybrid model).

RESULTS

The models' accuracy metrics obtained from the two different datasets were compared. The results evidenced the greater effectiveness of the hybrid model in the diagnostic prediction for the pathologies of interest.

CONCLUSIONS

When analysing the different methods of classification and clustering used, the better rates related to the precision and sensitivity of the pathologies under study were obtained with hybrid models with support of ensemble methods.

The Design, Development and Evaluation of the Vegetarian Lifestyle Index on Dietary Patterns among Vegetarians and Non-Vegetarians

Traditionally, healthful diets and lifestyles have been examined only in relation to single nutrients, foods, or food groups in terms of dietary exposure. An alternative approach is to conceptualize an index based on vegetarian food pyramid guidelines as a measure of overall diet and lifestyle quality. Our objectives were to: (1) develop the Vegetarian Lifestyle Index (VLI); and (2) evaluate adherence to the Vegetarian Food Guide Pyramid (VFGP) among a low-risk population of Adventists. The index was based on the operationalization of 14 dietary and lifestyle components. All components were equally weighted. Higher score reflected greater adherence to the VFGP. The analytic sample (n = 90,057) comprised 47.7% non-vegetarians, 5.6% semi-, 10.1% pesco-, and 29.0% lacto-ovo-vegetarians, and 7.7% vegans, of which 1.1% were current smokers and 9.9% were alcohol consumers. Population mean VLI score was 7.43 (SD = 1.75) ranging from 1 to 12.5. Non-vegetarians (6.14; 95% confidence interval (CI), 6.06⁻6.21) had a significantly lower mean compared to semi- (7.31; 95% CI, 7.22⁻7.40), pesco- (7.41; 95% CI, 7.32⁻7.49), and lacto-ovo-vegetarians (8.16; 95% CI, 8.08⁻8.24), as well as vegans (8.88; 95% CI, 8.78⁻8.96). Vegetarians scored on average 1.18 to 2.73 more points than their non-vegetarian counterparts. Results demonstrate that the index has strong discriminant ability across distinct dietary patterns. Additionally, the VLI provides a useful measure of diet and lifestyle adherence to further refine vegetarian food pyramid guidelines.

Patterns and predictors of clustered risky health behaviors among adult survivors of childhood cancer: A report from the Childhood Cancer Survivor Study

BACKGROUND

Health complications related to childhood cancer may be influenced by risky health behaviors (RHBs), particularly when RHBs co-occur. To the authors' knowledge, only limited information is available describing how RHBs cluster among survivors of childhood cancer and their siblings and the risk factors for co-occurring RHBs.

METHODS

Latent class analysis was used to identify RHB clusters using longitudinal survey data regarding smoking, alcohol use, and physical activity from adult survivors (4184 survivors) and siblings (1598 siblings) in the Childhood Cancer Survivor Study. Generalized logistic regression was used to evaluate associations between demographic characteristics, treatment exposures, psychological distress, health conditions, and cluster membership.

RESULTS

Three RHB clusters were identified: a low-risk cluster, an insufficiently active cluster, and a high-risk cluster (tobacco and risky alcohol use and insufficient activity). Compared with siblings, survivors were more likely to be in the insufficiently active cluster (adjusted odds ratio [ORadj ], 1.17; 95% confidence interval [95% CI], 1.06-1.27) and were less likely to be in the high-risk cluster (ORadj , 0.79; 95% CI, 0.69-0.88). Risk factors for membership in the high-risk cluster included psychological distress (ORadj , 2.76; 95% CI, 1.98-3.86), low educational attainment (ORadj , 7.49; 95% CI, 5.15-10.88), income <$20,000 (ORadj , 2.62; 95% CI, 1.93-3.57), being divorced/separated or widowed (ORadj , 1.36; 95% CI, 1.03-1.79), and limb amputation (ORadj , 1.52; 95% CI, 1.03-2.24). Risk factors for the insufficiently active cluster included chronic health conditions, psychological distress, low education or income, being obese or overweight, female sex, nonwhite race/ethnicity, single marital status, cranial radiation, and cisplatin exposure.

CONCLUSIONS

RHBs co-occur in survivors of childhood cancer and their siblings. Economic and educational disadvantages and psychological distress should be considered in screening and interventions to reduce RHBs. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2747-2756. © 2016 American Cancer Society.

A generic coding approach for the examination of meal patterns

BACKGROUND

Meal pattern analysis can be complex because of the large variability in meal consumption. The use of aggregated, generic meal data may address some of these issues.

OBJECTIVE

The objective was to develop a meal coding system and use it to explore meal patterns.

DESIGN

Dietary data were used from the National Adult Nutrition Survey (2008-2010), which collected 4-d food diary information from 1500 healthy adults. Self-recorded meal types were listed for each food item. Common food group combinations were identified to generate a number of generic meals for each meal type: breakfast, light meals, main meals, snacks, and beverages. Mean nutritional compositions of the generic meals were determined and substituted into the data set to produce a generic meal data set. Statistical comparisons were performed against the original National Adult Nutrition Survey data. Principal component analysis was carried out by using these generic meals to identify meal patterns.

RESULTS

A total of 21,948 individual meals were reduced to 63 generic meals. Good agreement was seen for nutritional comparisons (original compared with generic data sets mean ± SD), such as fat (75.7 ± 29.4 and 71.7 ± 12.9 g, respectively, P = 0.243) and protein (83.3 ± 26.9 and 80.1 ± 13.4 g, respectively, P = 0.525). Similarly, Bland-Altman plots demonstrated good agreement (<5% outside limits of agreement) for many nutrients, including protein, saturated fat, and polyunsaturated fat. Twelve meal types were identified from the principal component analysis ranging in meal-type inclusion/exclusion, varying in energy-dense meals, and differing in the constituents of the meals.

CONCLUSIONS

A novel meal coding system was developed; dietary intake data were recoded by using generic meal consumption data. Analysis revealed that the generic meal coding system may be appropriate when examining nutrient intakes in the population. Furthermore, such a coding system was shown to be suitable for use in determining meal-based dietary patterns.

Capturing changes in dietary patterns among older adults: a latent class analysis of an ageing Irish cohort

OBJECTIVE

Data-driven approaches to dietary patterns are under-utilized; latent class analyses (LCA) are particularly rare. The present study used an LCA to identify subgroups of people with similar dietary patterns, explore changes in dietary patterns over a 10-year period and relate these dynamics to sociodemographic factors and health outcomes.

DESIGN

The 1998 baseline and 2008 follow-up of the Cork and Kerry Diabetes and Heart Disease Study. Diets were assessed with a standard FFQ. LCA, under the assumption of conditional independence, was used to identify mutually exclusive subgroups with different dietary patterns, based on food group consumption.

SETTING

Republic of Ireland.

SUBJECTS

Men and women aged 50-69 years at baseline (n 923) and at 10-year follow-up (n 320).

RESULTS

Three dietary classes emerged: Western, Healthy and Low-Energy. Significant differences in demographic, lifestyle and health outcomes were associated with class membership. Between baseline and follow-up most people remained 'stable' in their dietary class. Most of those who changed class moved to the Healthy class. Higher education was associated with transition to a healthy diet; lower education was associated with stability in an unhealthy pattern. Transition to a healthy diet was associated with higher CVD risk factors at baseline: respondents were significantly more likely to be smokers, centrally obese and to have hypertension (non-significant).

CONCLUSIONS

LCA is useful for exploring dietary patterns transitions. Understanding the predictors of longitudinal stability/transitions in dietary patterns will help target public health initiatives by identifying subgroups most/least likely to change and most/least likely to sustain a change.

Association of self-reported sleep duration with eating behaviors of American adults: NHANES 2005-2010

BACKGROUND

Published evidence suggests an inverse association between sleep duration and body weight status.

OBJECTIVE

We examined the association of sleep duration with eating behaviors reported by adult Americans to understand the relation between sleep duration and body weight status.

DESIGN

This cross-sectional study used sleep duration and dietary data from the continuous NHANES conducted from 2005 to 2010 (n = 15,199, age ≥20 y). Eating behaviors examined included the following: reporting of and energy from main meals (breakfast, lunch, and dinner) and snacks (before breakfast, after dinner, and after 2000 h), intermeal intervals, time of day of main meal reporting, and intakes of macronutrients and beverages. Multiple regression methods were used to examine the independent association of hours of sleep duration grouped as short (≤6 h), average (7-8 h), and long (≥9 h) with eating behavior outcomes.

RESULTS

Relative to average-duration sleepers, a smaller percentage of short-duration sleepers mentioned breakfast, lunch (women only), and dinner in the recall (P ≤ 0.04). They also reported a lower mean percentage of energy from main meals but higher energy from all snacks (P ≤ 0.0004) and after 2000 h (P = 0.03). Short-duration sleepers reported the earliest eating time of the first episode and the latest time of the last eating episode. Absolute amounts of sugar and caffeine and percentage of energy from beverages (women only) were higher in short-duration sleepers. However, the total number of eating episodes and energy intake were not related with sleep duration.

CONCLUSIONS

Short-duration sleepers began eating earlier and ended their eating later in the day, but despite the longer eating period, they did not report more eating events. Profiles of the relative contribution of main meals and snacks, at or after 2000 h eating, and beverages in short-duration sleepers were suggestive of eating behaviors that may increase energy intake, but 24-h energy intake did not differ among categories of sleep duration.

Adolescent time use clusters: a systematic review

PURPOSE

Recent research suggests that patterns or clusters of time use may affect health in ways that cannot be explained by the effect of individual behaviors alone. The aim of this research was to systematically review the literature examining adolescent time use clusters and associated correlates.

METHODS

Systematic searches of six online databases for relevant observational studies were conducted. At least two authors reviewed abstract and full text selection meeting eligibility criteria. Included studies were quality scored, had data extracted, and cluster types and cluster associations interpreted.

RESULTS

Nineteen studies were identified for inclusion, and 18 of them investigated cluster-correlate associations. Twenty-nine cluster types were identified, characterized by both individual (e.g., church) and co-occurring behaviors (e.g., physical activity and screen [technoactive]). Nineteen correlate categories were identified (e.g., socioeconomic and weight status). Consistent patterns of cluster-correlate association were found. For example, the technoactive cluster type is more likely to be male and to have low school orientation.

CONCLUSIONS

Despite the between-study differences, consistent cluster and cluster-correlate patterns were still evident. Cluster analysis of adolescent time use behaviors appears to be an emerging and useful classification technique, one which may have implications for targeted health-related interventions.

Translating health psychology into effective health communication: the american healthstyles audience segmentation project

This article presents a health lifestyle audience segmentation analysis based primarily on social cognitive theory. Two linked mail surveys were conducted among a representative group of US adults (N = 2967). Segmentation variables included data on five health behaviors (smoking, alcohol consumption, physical activity, nutrition and weight control), internal personal and social/ environmental variables associated with each of the health behaviors, as well as health value, sensation- seeking, life satisfaction and age. K-means classification analysis was employed; seven health lifestyles were identified. The majority of the health lifestyles are reliable, and as a whole, all demonstrate both discriminative, construct and predictive validity. The health-lifestyle audience segments are briefly profiled, and an argument is made that health- lifestyle segmentation, more than demographic or behavioral segmentation alone, can advance the goals of public health communication.

The use of cluster analysis to derive dietary patterns: methodological considerations, reproducibility, validity and the effect of energy mis-reporting

Over the last three decades, dietary pattern analysis has come to the forefront of nutritional epidemiology, where the combined effects of total diet on health can be examined. Two analytical approaches are commonly used: a priori and a posteriori. Cluster analysis is a commonly used a posteriori approach, where dietary patterns are derived based on differences in mean dietary intake separating individuals into mutually exclusive, non-overlapping groups. This review examines the literature on dietary patterns derived by cluster analysis in adult population groups, focusing, in particular, on methodological considerations, reproducibility, validity and the effect of energy mis-reporting. There is a wealth of research suggesting that the human diet can be described in terms of a limited number of eating patterns in healthy population groups using cluster analysis, where studies have accounted for differences in sex, age, socio-economic status, geographical area and weight status. Furthermore, patterns have been used to explore relationships with health and chronic diseases and more recently with nutritional biomarkers, suggesting that these patterns are biologically meaningful. Overall, it is apparent that consistent trends emerge when using cluster analysis to derive dietary patterns; however, future studies should focus on the inconsistencies in methodology and the effect of energy mis-reporting.

Clustering of lifestyle factors and association with overweight in adolescents of the Kiel Obesity Prevention Study

OBJECTIVE

To identify lifestyle clusters in adolescents and to characterize their association with overweight and obesity.

DESIGN

Cross-sectional and longitudinal data of the Kiel Obesity Prevention Study.

SETTING

Schools in Kiel, Germany.

SUBJECTS AND METHODS

Cross-sectional data of 1894 adolescents aged 14 years and 4-year longitudinal data of a subsample of 389 children aged 10 and 14 years. Self-reported data of physical activity, modes of commuting to school, media time, nutrition, alcohol consumption and smoking were used to identify lifestyle clusters with two-step cluster analysis. Obesity indices (height, weight, waist circumference and fat mass (FM)) were measured.

RESULTS

Three lifestyle clusters were identified: a 'low activity and low-risk behaviour' cluster (cluster 1: n 740, 39·1 %); a 'high media time and high-risk behaviour' cluster (cluster 2: n 498, 26·3 %); and a 'high activity and medium-risk behaviour' cluster (cluster 3: n 656, 34·6 %). Strictly speaking, none of these clusters was considered to be markedly healthy. The prevalence of overweight and obesity tended to be lower in cluster 3 (15·9 %) than in clusters 1 (20·4 %) and 2 (20·5 %; P = 0·053). Longitudinally, 4-year changes in FM were found to be lowest in cluster 2, but the 4-year incidence rate of obesity was lowest in cluster 3.

CONCLUSIONS

Explicit healthy lifestyles do not exist, but an active lifestyle reduces the incidence of obesity. In adolescents, health promotion should take into account the diversity of lifestyles and address specific lifestyle clusters.

Modeling the long term health outcomes and cost-effectiveness of two interventions promoting fruit and vegetable intake among schoolchildren

This study provides an example on how to assess the cost-effectiveness of a nation wide implementation of two school-based interventions promoting fruit and vegetable intake among primary schoolchildren in the Netherlands compared to 'no intervention' and to each other. Data collection using self-report questionnaires in both studies was conducted between 2003 and 2005. Effects of the intervention in terms of fruit and vegetable intake were assessed and epidemiological modeling (conducted in 2008) was used to estimate the number of disability-adjusted life years gained over the lifetime of all 10 years old in the Netherlands. We assumed 30% of the effect on consumption was permanent. Incremental cost effectiveness ratios (ICER) and net monetary benefits (NMB) were estimated and one-way and probabilistic sensitivity analyses were conducted. The ICER for the Pro Children intervention in comparison with no intervention was estimated at €5728/DALY and the ICER for the Schoolgruiten intervention in comparison with no intervention at €10,674/DALY. Using the Dutch per capita income as a decision threshold (€19,600) the probability that the Pro Children intervention was cost-effective in comparison with no intervention was 80% and that the Schoolgruiten intervention was cost-effective in comparison with no intervention was 68%. The Pro Children had a 70% chance of being dominant over the Schoolgruiten intervention in terms of cost-effectiveness. The current cost-effectiveness model shows that both the Pro Children intervention and the Schoolgruiten intervention were cost-effective in comparison with no intervention. Extensive sensitivity analyses showed that the conclusions were sensitive to the discount rate and the proportion of effects that remains lifelong.

A systematic review of studies on socioeconomic inequalities in dietary intakes associated with weight gain and overweight/obesity conducted among European adults

This Review examined socioeconomic inequalities in intakes of dietary factors associated with weight gain, overweight/obesity among adults in Europe. Literature searches of studies published between 1990 and 2007 examining socioeconomic position (SEP) and the consumption of energy, fat, fibre, fruit, vegetables, energy-rich drinks and meal patterns were conducted. Forty-seven articles met the inclusion criteria. The direction of associations between SEP and energy intakes were inconsistent. Approximately half the associations examined between SEP and fat intakes showed higher total fat intakes among socioeconomically disadvantaged groups. There was some evidence that these groups consume a diet lower in fibre. The most consistent evidence of dietary inequalities was for fruit and vegetable consumption; lower socioeconomic groups were less likely to consume fruit and vegetables. Differences in energy, fat and fibre intakes (when found) were small-to-moderate in magnitude; however, differences were moderate-to-large for fruit and vegetable intakes. Socioeconomic inequalities in the consumption of energy-rich drinks and meal patterns were relatively under-studied compared with other dietary factors. There were no regional or gender differences in the direction and magnitude of the inequalities in the dietary factors examined. The findings suggest that dietary behaviours may contribute to socioeconomic inequalities in overweight/obesity in Europe. However, there is only consistent evidence that fruit and vegetables may make an important contribution to inequalities in weight status across European regions.

Dietary patterns are associated with lower incidence of type 2 diabetes in middle-aged women: the Shanghai Women's Health Study

BACKGROUND

Data linking risk of type 2 diabetes (T2D) and dietary patterns in Chinese populations are scarce.

METHODS

A population-based prospective study of 64,191 middle-aged women in urban Shanghai, China, who were free of T2D and other chronic diseases at study recruitment, was conducted. Dietary intake, physical activity and anthropometric measurements were assessed through in-person interviews. Dietary patterns were assessed by using K-means cluster analysis. Cox regression model was used to evaluate the association of dietary patterns with the risk of T2D.

RESULTS

We identified three dietary clusters in this population. Cluster 1 (56.3%; N = 36,159) had the highest intake of staples, cluster 2 (40.4%: N = 25,948) had the highest intake of dairy milk, and cluster 3 (2.9%; N = 1843) had the highest energy intake. Participants in cluster 2 had lower prevalence of obesity, central obesity and hypertension at baseline. Using cluster 1 as the reference, participants in cluster 2 had a lower incidence of T2D after 6.9 years of follow-up [relative risk (RR) 0.78; 95% confidence interval (CI) 0.71-0.86]. The RR for the incidence of T2D for cluster 3 compared with cluster 1 was 1.05 (95% CI 0.81-1.35). The association was not modified by age category, body mass index category, waist-to-hip ratio category or exercise participation.

CONCLUSIONS

We identified and characterized dietary patterns in middle-aged Chinese women by using cluster analysis. We identified a dietary pattern low in staple foods and high in dairy milk, which was associated with lower risk of T2D. Study of dietary patterns will help elucidate links between diet and disease, and contribute to the development of healthy eating guidelines for health promotion.

How to find information on national food and nutrient consumption surveys across Europe: systematic literature review and questionnaires to selected country experts are both good strategies

The present research was conducted within the framework of the EURopean micronutrient RECommendations Aligned project. In order to identify the best practice in assessing nutrient intakes, a search strategy for collecting data from national food consumption surveys/studies in Europe was developed. Systematic literature searches were carried out on twenty-eight European and the four European Free Trade Association countries. A questionnaire was also sent to two to five experts in each country. Systematic reviews using PubMed yielded 12 703 abstracts that were reduced to 200 studies using inclusion and exclusion criteria. Similarly, a search of ministry web sites yielded 3033 hits, and subsequently reduced to nine surveys. Belgium, France, Germany, Ireland, Sweden, Spain and the United Kingdom were the countries with most data and Slovenia and Liechtenstein were those with the least. Seventy-eight expert questionnaires were obtained from all countries except for Liechtenstein, Luxembourg and Slovakia. Detailed results and references are given. A systematic search and questionnaires are equally good at identifying national surveys across countries. Literature searching provides globally accessible and objective information albeit limited, whereas the questionnaire provides information that, depending upon responders, can be more complete. A combination of both strategies is recommended.

Associations between food patterns defined by cluster analysis and colorectal cancer incidence in the NIH-AARP diet and health study

BACKGROUND/OBJECTIVES

To examine associations between food patterns, constructed with cluster analysis, and colorectal cancer incidence within the National Institutes of Health-AARP Diet and Health Study.

SUBJECTS/METHODS

A prospective cohort, aged 50-71 years at baseline in 1995-1996, followed until the end of 2000. Food patterns were constructed, separately in men (n=293,576) and women (n=198,730), with 181 food variables (daily intake frequency per 1000 kcal) from a food frequency questionnaire. Four large clusters were identified in men and three in women. Cox proportional hazards regression examined associations between patterns and cancer incidence.

RESULTS

In men, a vegetable and fruit pattern was associated with reduced colorectal cancer incidence (multivariate hazard ratio, HR: 0.85; 95% confidence interval, CI: 0.76, 0.94), when compared to less salutary food choices. Both the vegetable and fruit pattern and a fat-reduced foods pattern were associated with reduced rectal cancer incidence in men. In women, a similar vegetable and fruit pattern was associated with colorectal cancer protection (age-adjusted HR: 0.82; 95% CI: 0.70, 0.95), but the association was not statistically significant in multivariate analysis.

CONCLUSIONS

These results, together with findings from previous studies support the hypothesis that micronutrient dense, low-fat, high-fiber food patterns protect against colorectal cancer.

Dietary patterns among a national sample of British children aged 1 1/2-4 1/2 years

OBJECTIVE

Using a nationally representative sample, to identify groups among British children aged 1 1/2-4 1/2 years who report similar patterns of diet.

DESIGN

Nationally representative dietary survey, using 4 d weighed dietary records, of girls and boys aged 1 1/2-4 1/2 years living in private households in Great Britain in 1992-1993. Cluster analysis was used to aggregate individuals into diet groups.

SETTING

Great Britain.

PARTICIPANTS

Eight hundred and forty-eight boys and 827 girls.

RESULTS

Three clusters were identified for girls and three for boys. Among boys the most prevalent cluster was 'Healthy Diet' (52.3%), the second was 'Convenience Diet' (38.3%) and the third was 'Traditional Diet' (9.3%). Among girls, the most prevalent dietary cluster was 'Healthy Diet' (58.7%), followed by a 'Convenience Diet' (36.6%) and 'Traditional Diet' (4.3%). There were important differences in nutrient profile, sociodemographic and behavioural characteristics between clusters.

CONCLUSIONS

Cluster analysis identified three groups among both girls and boys which differed not only in terms of reported dietary intake, but also with respect to nutrient intake, social and behavioural characteristics. The groups identified could provide a useful basis for the development, monitoring and targeting of public health nutrition policy for pre-school children in the UK. Further research is needed on the consequences for chronic disease in the future for these children.

Health effects of quercetin: from antioxidant to nutraceutical

Quercetin, a member of the flavonoids family, is one of the most prominent dietary antioxidants. It is ubiquitously present in foods including vegetables, fruit, tea and wine as well as countless food supplements and is claimed to exert beneficial health effects. This includes protection against various diseases such as osteoporosis, certain forms of cancer, pulmonary and cardiovascular diseases but also against aging. Especially the ability of quercetin to scavenge highly reactive species such as peroxynitrite and the hydroxyl radical is suggested to be involved in these possible beneficial health effects. Consequently, numerous studies have been performed to gather scientific evidence for these beneficial health claims as well as data regarding the exact mechanism of action and possible toxicological aspects of this flavonoid. The purpose of this review is to evaluate these studies in order to elucidate the possible health-beneficial effects of the antioxidant quercetin. Firstly, the definitions as well as the most important aspects regarding free radicals, antioxidants and oxidative stress will be discussed as background information. Subsequently, the mechanism by which quercetin may operate as an antioxidant (tested in vitro) as well as the potential use of this antioxidant as a nutraceutical (tested both ex vivo and in vivo) will be discussed.

Health-related behaviours as predictors of mortality and morbidity in Australian Aborigines

OBJECTIVE

To examine predictors of coronary heart disease (CHD) and all-cause mortality in Aboriginal Australians.

METHOD

In 1988-89, a survey of Western Australian Aborigines (256 women, 258 men) aged 15-88 years documented diet, alcohol and smoking habits. Linkage to mortality and hospital admissions to the end of 2002 provided longitudinal data for modelling of coronary heart disease endpoints and all-cause mortality using Cox regression.

RESULTS

Coronary heart disease risk increased with smoking (HR 2.62, 95% CI: 1.19, 5.75), consumption of processed meats >once/week (HR 2.21, 95% CI: 1.05, 4.63), eggs >twice/week (HR 2.59, 95% CI: 1.11, 6.04) and using spreads on bread (HR 3.14. 95% CI: 1.03, 9.61). All-cause mortality risk was lower with exercise >once/week (HR 0.51, 95% CI 0.26, 1.05), increased in ex-drinkers (HR 3.66, 95% CI: 1.08, 12.47), heavy drinkers (HR 5.26, 95% CI: 1.46, 7.52) and with consumption of take away foods >nine times/month (HR 1.78, 95% CI 0.96, 3.29). Greater alcohol intake, smoking and adverse dietary choices clustered in 53% of men and 56% of women and increased risk of coronary heart disease (HR 2.1, 95% CI: 1.1, 4.0) and all-cause mortality (HR 2.3, 95% CI: 1.2, 4.2).

CONCLUSION

Lifestyle in Aboriginal Australians predicts coronary heart disease and all-cause mortality. Clustering of adverse behaviours is common and increases risk of coronary heart disease and death.

Patterns in sedentary and exercise behaviors and associations with overweight in 9-14-year-old boys and girls--a cross-sectional study

Background

Before starting interventions addressing energy-balance related behaviors, knowledge is needed about the prevalence of sedentary behaviors and low physical exercise, their interrelationships, possible gender differences. Therefore this study aimed to describe gender differences in sedentary and physical exercise behaviors and their association with overweight status in children from nine European countries. Additionally, to identify clusters of children sharing the same pattern regarding sedentary and physical exercise behavior and compare these groups regarding overweight status.

Methods

Cross-sectional study among 11-year-old children in nine countries (n = 12538). Self-administered questionnaires assessed the time spent on TV viewing during dinner and during the day, PC use and on physical exercise. The parents reported children's weight and height. Descriptive statistics, cluster analyses, and logistic regression analyses were used for data analyses.

Results

Boys spent more time on sedentary behaviors but also more on physical exercise than girls. High TV viewing and low exercise behavior independently increased the risk of being overweight. Based on the behaviors, five clusters were identified. Among boys, clear associations with being overweight were found, with the most unhealthy behavior pattern having the highest risks of being overweight. Among girls, high TV viewers and high PC users had increased risk of being overweight. In girls sedentary behaviors seemed more important than physical exercise with regard to overweight status.

Conclusion

Despite selective non-response on BMI and reliance on self-reports, the associations between clusters and overweight in boys were clear, and differences between boys and girls regarding the behaviors and risks for overweight are noteworthy. These differences need to be considered when developing tailored intervention strategies for prevention of overweight.

Dietary patterns in middle-aged Irish men and women defined by cluster analysis

Objectives:

To identify and characterise dietary patterns in a middle-aged Irish population sample and study associations between these patterns, sociodemographic and anthropometric variables and major risk factors for cardiovascular disease.

Design:

A cross-sectional study.

Subjects and methods:

A group of 1473 men and women were sampled from 17 general practice lists in the South of Ireland. A total of 1018 attended for screening, with a response rate of 69%. Participants completed a detailed health and lifestyle questionnaire and provided a fasting blood sample for glucose, lipids and homocysteine. Dietary intake was assessed using a standard food-frequency questionnaire adapted for use in the Irish population. The food-frequency questionnaire was a modification of that used in the UK arm of the European Prospective Investigation into Cancer study, which was based on that used in the US Nurses' Health Study. Dietary patterns were assessed primarily by K-means cluster analysis, following initial principal components analysis to identify the seeds.

Results:

Three dietary patterns were identified. These clusters corresponded to a traditional Irish diet, a prudent diet and a diet characterised by high consumption of alcoholic drinks and convenience foods. Cluster 1 (Traditional Diet) had the highest intakes of saturated fat (SFA), monounsaturated fat (MUFA) and percentage of total energy from fat, and the lowest polyunsaturated fat (PUFA) intake and ratio of polyunsaturated to saturated fat (P:S). Cluster 2 (Prudent Diet) was characterised by significantly higher intakes of fibre, PUFA, P:S ratio and antioxidant vitamins (vitamins C and E), and lower intakes of total fat, MUFA, SFA and cholesterol. Cluster 3 (Alcohol & Convenience Foods) had the highest intakes of alcohol, protein, cholesterol, vitamin B12, vitamin B6, folate, iron, phosphorus, selenium and zinc, and the lowest intakes of PUFA, vitamin A and antioxidant vitamins (vitamins C and E). There were significant differences between clusters in gender distribution, smoking status, physical activity, body mass index, waist circumference and serum homocysteine concentrations.

Conclusion:

In this general population sample, cluster analysis methods yielded two major dietary patterns: prudent and traditional. The prudent dietary pattern is associated with other health-seeking behaviours. Study of dietary patterns will help elucidate links between diet and disease and contribute to the development of healthy eating guidelines for health promotion.

Who eats four or more servings of fruit and vegetables per day? Multivariate classification tree analysis of data from the 1998 Survey of Lifestyle, Attitudes and Nutrition in the Republic of Ireland

Objective

To identify, using the novel application of multivariate classification trees, the socio-economic, sociodemographic and health-related lifestyle behaviour profile of adults who comply with the recommended 4 or more servings per day of fruit and vegetables.

Design

Cross-sectional 1998 Survey of Lifestyle, Attitudes and Nutrition.

Setting

Community-dwelling adults aged 18 years and over on the Republic of Ireland electoral register.

Subjects

Six thousand five hundred and thirty-nine (response rate 62%) adults responded to a self-administered postal questionnaire, including a semi-quantitative food-frequency questionnaire.

Results

The most important determining factor of compliance with the fruit and vegetable dietary recommendations was gender. A complex constellation of sociodemographic and socio-economic factors emerged for males whereas the important predictors of 4 or more servings of fruit and vegetable consumption among females were strongly socio-economic in nature. A separate algorithm was run to investigate the importance of health-related lifestyle and other dietary factors on compliance with the fruit and vegetable recommendations. Following an initial split on compliance with dairy recommendations, a combination of non-dietary behaviours showed a consistent pattern of healthier options more likely to lead to compliance with fruit and vegetable recommendations. There did, however, appear to be a compensatory element between the variables, particularly around smoking, suggesting the non-existence of an exclusive lifestyle for health risk.

Conclusions

Material and structural influences matter very much for females in respect to compliance with fruit and vegetable recommendations. For males, while these factors are important they appear to be mediated through other more socially contextual-type factors. Recognition of the role that each of these factors plays in influencing dietary habits of men and women has implications for the manner in which dietary strategies and policies are developed and implemented.

Comparative strategies for using cluster analysis to assess dietary patterns

OBJECTIVES

To characterize dietary patterns using two different cluster analysis strategies.

DESIGN

In this cross-sectional study, diet information was assessed by five 24-hour recalls collected over 10 months. All foods were classified into 24 food subgroups. Demographic, health, and anthropometric data were collected via home visit.

SUBJECTS

One hundred seventy-nine community-dwelling adults, aged 66 to 87 years, in rural Pennsylvania.

STATISTICAL ANALYSIS

Cluster analysis was performed.

RESULTS

The methods differed in the food subgroups that clustered together. Both methods produced clusters that had significant differences in overall diet quality as assessed by Healthy Eating Index (HEI) scores. The clusters with higher HEI scores contained significantly higher amounts of most micronutrients. Both methods consistently clustered subgroups with high energy contribution (eg, fats and oils and dairy desserts) with a lower HEI score. Clusters resulting from the percent energy method were less likely to differentiate fruit and vegetable subgroups. The higher diet quality dietary pattern derived from the number of servings method resulted in more favorable weight status.

CONCLUSIONS

Cluster analysis of food subgroups using two different methods on the same data yielded similarities and dissimilarities in dietary patterns. Dietary patterns characterized by the number of servings method of analysis provided stronger association with weight status and was more sensitive to fruit and vegetable intake with regard to a more healthful dietary pattern within this sample. Public health recommendations should evaluate the methodology used to derive dietary patterns.

Clustering of behavioural risk factors and their association with subjective health

OBJECTIVES

To describe the clustering of behavior-related risk factors in the adult population of the Autonomous Community of Madrid (Spain) and evaluate the association between the level of aggregation of these factors and suboptimal subjective health.

METHODS

Data were drawn from the Non-communicable Disease Risk-Factor Surveillance System (Sistema de Vigilancia de Factores de Riesgo asociados a Enfermedades No Transmisibles [SIVFRENT]). We studied the associations between smoking, high-risk alcohol consumption, leisure-time sedentariness and unbalanced diet in 16,043 persons aged 18-64 years and compared the observed against the expected proportions. Logistic regression was used to estimate the association between clustering of risk factors and suboptimal health (fair, poor and very poor).

RESULTS

Almost 20% of subjects had 3 or 4 risk factors simultaneously. Most combinations of 3 risk factors exceeded expectations and, in particular, 4 factor clustering yielded observed/expected quotients of 2.15 (95% confidence interval [CI]: 1.93-2.38) in men and 2.96 (95% CI, 2.46-3.46) in women. In both sexes, the individual factor most closely associated with the remaining risk factors was smoking. Aggregation of risk factors was more frequent among men, younger age groups and subjects with low educational level. Compared with persons with none of the 4 risk factors, those that simultaneously had 3 or 4 more frequently reported suboptimal subjective health (OR = 2.49; 95% CI, 1.59-3.90 in men and OR = 1.96; 95% CI, 1.29-2.97 in women).

CONCLUSIONS

Behavior-related risk factors tend to aggregate, and this accumulation is higher among men, younger age groups, and subjects with a low educational level. A greater level of clustering is associated with a higher frequency of suboptimal perceived health.

Polyphenols and disease risk in epidemiologic studies

Plant polyphenols, a large group of natural antioxidants, are serious candidates in explanations of the protective effects of vegetables and fruits against cancer and cardiovascular diseases. Epidemiologic studies are useful for evaluation of the human health effects of long-term exposure to physiologic concentrations of polyphenols, but reliable data on polyphenol contents of foods are still scarce. The aim of this review is to summarize available epidemiologic data on the health effects of polyphenols, focusing on the flavonoid subclasses of flavonols, flavones, and catechins and on lignans. Data obtained to date suggest beneficial effects of both flavonoids and lignans on cardiovascular diseases but not on cancer, with the possible exception of lung cancer. There is a need for more research on stroke and lung diseases such as asthma and chronic obstructive pulmonary disease. Most studies to date have included only flavonols and flavones. With data becoming available for other polyphenols, these compounds should be included in future studies. Careful design of prospective studies is important to offset some of the major drawbacks of epidemiologic studies, including residual confounding (by smoking and other dietary factors) and exposure assessment.

[Factors associated with dietary patterns in the urban Brazilian population]

This study evaluated factors associated with dietary patterns in the Brazilian population based on the Living Standards Survey conducted in the Northeast and Southeast regions of the country. Multi-stage probability sampling was employed to select the households, and for the present analysis 5,121 adults aged 20 to 50 years were included. Pregnant women and individuals reporting chronic health conditions were excluded. Through principal component analysis, two major family dietary patterns were identified: a mixed pattern, in which all groups and foods have approximately the same factor loading, and a second pattern based main1y on rice and beans, which was called a traditional diet. Weight and height were measured in the households, and food intake was based on a 21-item semi-quantitative family questionnaire. The Northeast (as compared to the Southeast) was negatively associated with the mixed pattern. Body mass index was positively associated with the mixed pattern, whereas leisure physical activity and Black skin color were negatively associated with the mixed pattern. Schooling and income levels explained most of the dietary variance, but after adjusting for education and income, region of residence remained significantly associated and was the third most important explanatory variable.

Socioeconomic status over the life course and stages of cigarette use: initiation, regular use, and cessation

STUDY OBJECTIVE

To investigate the association between multiple indicators of socioeconomic status (SES) over the life course and three stages of cigarette use: initiation, regular use, and cessation.

DESIGN

Prospective birth cohort study.

SETTING

Providence, Rhode Island.

PARTICIPANTS

Subjects (n=657) aged 30 to 39 were offspring of participants in the Brown University cohort of the United States National Collaborative Perinatal Project started in 1959.

MAIN RESULTS

A significantly increased risk of smoking initiation was observed among people from lower socioeconomic backgrounds. Low SES in childhood also increased the risk for progression to regular smoking, and was associated with a reduced likelihood of smoking cessation. Progression to regular smoking and smoking persistence were also associated with lower adult SES.

CONCLUSIONS

Socioeconomic conditions over the life course accumulate to produce increased rates of smoking uptake and reduced rates of cessation among lower SES people. Addressing SES gradients in smoking will require persistent and extended intervention over multiple life stages.

Association of education with dietary intake among young adults in the bi-ethnic Coronary Artery Risk Development in Young Adults (CARDIA) cohort

OBJECTIVE

To examine associations of changes in dietary intake with education in young black and white men and women.

DESIGN

The Coronary Artery Risk Development in Young Adults (CARDIA) study, a multi-centre population-based prospective study. Dietary intake data at baseline and year 7 were obtained from an extensive nutritionist-administered diet history questionnaire with 700 items developed for CARDIA.

SETTING

Participants were recruited in 1985-1986 from four sites: Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; and Oakland, California.

SUBJECTS

Participants were from a general community sample of 703 black men (BM), 1006 black women (BW), 963 white men (WM) and 1054 white women (WW) who were aged 18-30 years at baseline. Analyses here include data for baseline (1985-1986) and year 7 (1992-1993).

RESULTS

Most changes in dietary intake were observed among those with high education (>or=12 years) at both examinations. There was a significant decrease in intake of energy from saturated fat and cholesterol and a significant increase in energy from starch for each race-gender group (P<0.001). Regardless of education, taste was considered an important influence on food choice.

CONCLUSION

The inverse relationship of education with changes in saturated fat and cholesterol intakes suggests that national public health campaigns may have a greater impact among those with more education.

Diet quality and risk of neural tube defects

Many studies have examined the impact of single nutrients on neural tube defect (NTD) risk, particularly folate. The impact of dietary patterns or nutrients in combination has received much less attention. This study examines the association of diet quality with NTD risk, using food frequency data from a population-based case-control study of NTDs (n=454 cases and 462 controls). The diet quality score was based on low (<10th percentile among controls) versus high (>90th percentile) values for intakes of iron, vitamins B(6) and A, calcium, folate, and percentage of kilocalories from fat and from sweets (range=0-14). Women with a low score (i.e., <4, or <10th percentile) had an elevated risk of an NTD-affected pregnancy (odds ratio 1.6, 95% CI 1.0-2.6). Stratified analyses suggested that the effect may be restricted to certain groups of women who may be at greater nutritional risk (i.e., women who did not take vitamin supplements or regularly consume breakfast cereals before pregnancy).

Diversity of dietary patterns observed in the European Prospective Investigation into Cancer and Nutrition (EPIC) project

OBJECTIVE

To describe the diversity in dietary patterns existing across centres/regions participating in the European Prospective Investigation into Cancer and Nutrition (EPIC).

DESIGN AND SETTING

Single 24-hour dietary recall measurements were obtained by means of standardised face-to-face interviews using the EPIC-SOFT software. These have been used to present a graphic multi-dimensional comparison of the adjusted mean consumption of 22 food groups.

SUBJECTS

In total, 35 955 men and women, aged 35-74 years, participating in the EPIC nested calibration study.

RESULTS

Although wide differences were observed across centres, the countries participating in EPIC are characterised by specific dietary patterns. Overall, Italy and Greece have a dietary pattern characterised by plant foods (except potatoes) and a lower consumption of animal and processed foods, compared with the other EPIC countries. France and particularly Spain have more heterogeneous dietary patterns, with a relatively high consumption of both plant foods and animal products. Apart from characteristics specific to vegetarian groups, the UK 'health-conscious' group shares with the UK general population a relatively high consumption of tea, sauces, cakes, soft drinks (women), margarine and butter. In contrast, the diet in the Nordic countries, The Netherlands, Germany and the UK general population is relatively high in potatoes and animal, processed and sweetened/refined foods, with proportions varying across countries/centres. In these countries, consumption of vegetables and fruit is similar to, or below, the overall EPIC means, and is low for legumes and vegetable oils. Overall, dietary patterns were similar for men and women, although there were large gender differences for certain food groups.

CONCLUSIONS

There are considerable differences in food group consumption and dietary patterns among the EPIC study populations. This large heterogeneity should be an advantage when investigating the relationship between diet and cancer and formulating new aetiological hypotheses related to dietary patterns and disease.

Dietary patterns and nutrient intakes of 7-year-old children taking part in an atherosclerosis prevention project in Finland

OBJECTIVE

To evaluate the dietary patterns of 7-year-old children participating in an atherosclerosis prevention project and the relationship of those dietary patterns to nutrient intakes and serum cholesterol values.

DESIGN

In the randomized, prospective Special Turku Coronary Risk Factor Intervention Project (STRIP) 1,062 children were randomly assigned to an intervention group (n=540; low-saturated fat, low-cholesterol diet) or to a control group (n=522; unrestricted diet) at 7 months of age.

SUBJECTS/SETTINGS

The intervention families received, at 6-month intervals, individualized counseling that focused on the known environmental atherosclerosis risk factors and aimed at reducing children's saturated fat and cholesterol intake. Nutrition counseling was targeted at the child but, because of the young age of the children, was given to the parents. When children were 7 years old, food and nutrient intakes of 307 intervention and 323 control children were studied using 4-day food records.

STATISTICAL ANALYSES PERFORMED

K-means cluster analysis was used to classify children into 4 groups on the basis of similarity of food intake. Differences in nutrient intakes and serum lipid concentrations between children in the 4 food intake clusters were evaluated using Tukey's multiple comparison test.

RESULTS

Intervention children dominated the bread, skim milk, and margarine cluster and the cereals, rice, and pasta cluster whereas the 1.5%-fat milk and butter cluster included mainly control children. Saturated fat intake was nearest to the recommendations, that is 11.7% and 11.9% of energy, in the bread, skim milk, and margarine cluster and the cereals, rice, and pasta cluster, respectively. Children in the bread, skim milk, and margarine cluster had 20% to 27% higher fiber intakes (P<.001) whereas children in the sugar and sweets cluster had markedly higher sugar intakes than children in other clusters (P<.001). Serum cholesterol concentrations were lower in those clusters with high dietary ratios of polyunsaturated to saturated fat.

CONCLUSION

Detailed and repeated dietary counseling of parents, starting when children are aged 7 months, that aims at decreasing children's exposure to known nutrition risk factors for coronary heart disease modifies children's food patterns and nutrient intakes toward expected values.

Food intake patterns and body mass index in observational studies

OBJECTIVE

To review studies of patterns of food intake, as assessed by diet index, factor analysis or cluster analysis, and their associations with body mass index or obesity (BMI/Ob).

DESIGN

Systematic literature review MEDLINE search with crosscheck of references.

STUDIES

Thirty observational studies relating food intake patterns to anthropometric information were identified and reviewed. Food intake patterns were defined using a diet index, factor or cluster analysis in 12, nine and nine studies, respectively. Measures of body mass were made concurrently with the diet assessment in all studies, and only in a few cases were the primary outcomes related to BMI/Ob.

RESULTS

The food intake patterns identified could, in most factor or cluster analysis studies, be categorised as: (a) meat, fatty, sweet or energy dense foods; (b) vegetables, fruit, whole grain and low-fat foods; or (c) by high alcohol consumption. The diet indexes were designed to capture a high diversity and/or food combinations matching the recommendations. The relationships with BMI/Ob were inconsistent-ten studies found that intake patterns, which we categorised as fatty, sweet or energy dense were positively associated with BMI/Ob, while similar patterns in four other studies were negatively associated with BMI. The significant associations between diet index score and BMI/Ob were consistently negative, while the associations between factor scores or cluster membership and BMI/Ob were less clear in terms of food intake pattern. Men and women had similar food intake patterns, but food intake patterns were less often positively associated with BMI/Ob in women. In 11 studies, there were no significant associations between food intake pattern and BMI/Ob.

CONCLUSION

This review showed that no consistent associations could be identified between BMI or Ob and food intake patterns, derived from diet index, factor analysis or cluster analysis. However, the heterogeneity of food intake patterns identified by such analyses and the lack of gold standards for the application of these techniques hampers consistent analysis of a relation between food intake patterns and health.

Evaluation of dietary quality in relationship to nutritional and lifestyle factors in elderly people of the US Framingham Heart Study and the European SENECA study

OBJECTIVE

To evaluate dietary quality of European and American elderly subjects using different derivatives of dietary patterns (dietary scores and clusters) and to investigate the relationship of these approaches to nutritional and lifestyle factors.

DESIGN

Data from the cross-sectional SENECA baseline study and Framingham Heart Study (original cohort and offspring) were used for data analysis. Food intake data were summarised into dietary clusters and into dietary scores (Healthy Diet Indicator and Mediterranean Diet Score). These measures of dietary quality were then tested for associations with lifestyle factors and measures of nutritional status.

SUBJECTS/SETTING

The study population, aged 70-77 y, consisted of 828 subjects from Framingham, MA (USA) and 1282 subjects from the following European centres: Hamme, Belgium; Roskilde, Denmark; Padua, Italy; Culemborg, The Netherlands; Vila Franca de Xira, Portugal; Betanzos, Spain; and Yverdon, Burgdorf and Bellinzona, Switzerland.

RESULTS

Dietary intake varied widely across the European and American research centres. In general, Southern European centres and Framingham had higher mean diet scores, indicating a higher dietary quality, than Northern European centres (MD-scores: 4.2-4.4 vs 2.7-3.5). Cluster analysis identified the following five dietary patterns characterised by: (1) sugar and sugar products; (2) fish and grain; (3) meat, eggs and fat; (4) milk and fruit; and (5) alcohol intake. The meat, eggs and fat pattern had significantly lower average dietary quality, as measured with all three diet scores than all other groups except the alcohol group. The fish and grain group had significantly better Mediterranean diet scores than all other groups.

CONCLUSIONS

Dietary scores and dietary clusters are complementary measures to classify dietary quality. The associations with nutritional and lifestyle factors indicate the adequate categorisation into dietary quality groups.

SPONSORSHIP

European Union, US Department of Agriculture, Agriculture Research Service, under agreement (58-1950-9-001), Haak Bastiaanse-Kuneman Foundation.

Identification of groups who report similar patterns of diet among a representative national sample of British adults aged 65 years of age or more

OBJECTIVES

Using a national representative sample to identify groups within the UK male and female population over 65 years who report similar patterns of diet.

DESIGN

National representative dietary survey, using 4-day weighed dietary records of men and women aged over 65 years old and living in private households in Great Britain in 1994-1995. Cluster analysis was used to aggregate individuals into diet groups.

SETTING

United Kingdom.

SUBJECTS

558 women and 539 men.

MAIN OUTCOME MEASURES

Consumption of predefined food groups, nutrient intakes, socio-economic, demographic and behavioural characteristics.

RESULTS

Three large clusters comprising 86% of the male population and three large clusters comprising 83% of the female population were identified. Among men, the most prevalent cluster was a "mixed diet" with elements from a traditional diet and some elements from a healthy diet (48% of the male population); the second was a "healthy diet" (21% of the male population); and the third was a "traditional diet high in alcohol" (17% of the male population). Among women, the most prevalent diet was a "sweet traditional diet" (33% of the female population); the second was a "healthy diet" (32% of the female population); and the last was a "mixed diet" with elements of the traditional diet and the healthy diet (18% of the female population). There were important differences in average nutrient intakes, socio-demographic and behavioural characteristics across these diet clusters.

CONCLUSIONS

Cluster analysis identified three diet groups among men and three among women. These differed not only in terms of reported dietary intake, but also with respect to their nutrient content, social and behavioural profile. The groups identified could provide a useful basis for health promotion based upon the diet clusters.

Analytical approaches to food-based dietary guidelines in the European setting

OBJECTIVE

To show the effects of statistical approaches of data analysis to be used in the development of Food-Based Dietary Guidelines (FBDG).

SETTING

Databases from dietary surveys in 6 European countries.

RESULTS

Quantile analysis based on iron intake among adult women resulted in differences among European countries regarding (macro) nutrient intake and consumption of food groups. However, in all countries women in the highest quartile had a higher intake of energy and dietary fibre and a higher intake of most food groups. In developing FBDG adjustment of energy intake is recommended. Discriminant analyses showed that among Dutch women potatoes, red meat, sausages, offal, savoury snacks, eggs and total vegetables were found to be the most predictive for differences in iron intake. Relatively high correlations were observed for iron and dietary fibre and iron and (some) B-vitamins. Examples from cluster and factor analysis showed that this type of analysis considers the complexity of the dietary pattern and could also be a helpful instrument in the development of FBDG.

CONCLUSIONS

The use of a nutrient distribution can be used as a minimum approach in developing FBDG. More advanced methods can also be used in addition to set priorities for FBDG and to analyse complete dietary patterns.

Validation of a dietary pattern approach for evaluating nutritional risk: the Framingham Nutrition Studies

OBJECTIVE

To validate the use of cluster analysis for characterizing population dietary patterns.

DESIGN

Cluster analysis was applied to a food frequency questionnaire to define dietary patterns. Independent estimates of nutrient intake were derived from 3-day food records. Heart disease risk factors were assessed using standardized protocols in a clinic setting.

SETTING

Adult women (n = 1,828) participating in the Framingham Offspring-Spouse study.

STATISTICAL ANALYSES

Age-adjusted mean nutrient intakes were determined for each cluster. Analysis of covariance was used to evaluate pairwise differences in intake across clusters. Compliance with published recommendations was determined for selected heart disease risk factors. Differences in age-adjusted compliance across clusters were evaluated using logistic regression.

RESULTS

Cluster analysis identified 5 distinct dietary patterns characterized by unique food behaviors and significantly different nutrient intake profiles. Patterns rich in fruits, vegetables, grains, low-fat dairy, and lean protein foods resulted in higher nutrient density. Patterns rich in fatty foods, added fats, desserts, and sweets were less nutrient-dense. Women who consumed an Empty Calorie pattern were less likely to achieve compliance with clinical risk factor guidelines in contrast to most other groups of women.

CONCLUSIONS

Cluster analysis is a valid tool for evaluating nutrition risk by considering overall patterns and food behaviors. This is important because dietary patterns appear to be linked with other health-related behaviors that confer risk for chronic disease. Therefore, insight into dietary behaviors of distinct clusters within a population can help to design intervention strategies for prevention and management of chronic health conditions including obesity and cardiovascular disease.

Dietary patterns among a national random sample of British adults

STUDY OBJECTIVES

To identify groups within the UK male and female population who report similar patterns of diet.

DESIGN

National representative dietary survey, using seven day weighed dietary records, of men and women aged 16-64 years living in private households in Great Britain in 1986-7. Cluster analysis was used to aggregate participants into diet groups.

SETTING

Great Britain.

PARTICIPANTS

1087 men and 1110 women.

RESULTS

93% of men and 86% of women fell into one of four distinct diet groups. Among men the most prevalent diet group was "beer and convenience food" (34% of the male population); second was "traditional British diet" (18%); third was "healthier but sweet diet" (17.5%) and fourth was "healthier diet " (17%). Among women, the most prevalent diet group was " traditional British diet" (32%); second, was "healthy cosmopolitan diet" (25%); third was a "convenience food diet" (21%); and fourth was "healthier but sweet diet" (15%). There were important differences in nutrient profile, sociodemographic and behavioural characteristics between diet groups.

CONCLUSIONS

Cluster analysis identified four diet groups among men and four among women, which differed not only in terms of reported dietary intakes, but also with respect to nutrient, social and behavioural profiles. The groups identified could provide a useful basis for development, monitoring and targeting of public health nutrition policy in the UK.

The choice of a diet quality indicator to evaluate the nutritional health of populations

BACKGROUND

The USA and Canada both want to reduce social health inequalities in their population. These two countries have recently begun a process of harmonization of their nutrient recommendations.

OBJECTIVE

To develop a standardized indicator to measure the impact of these recommendations on the health of different social groups in North America. The authors have compared three of the methods currently used for measuring overall diet quality for a population.

DESIGN AND SETTING

The three methods, adjusted to the 1990 Canadian nutrition recommendations, were used to analyse the Québec Nutrition Survey data collected by Santé Québec in 1990.

RESULTS

The authors found that the indicator developed by Kennedy and collaborators works best for analysing the Québec data. Moreover, it allows comparisons with the USA. Some questions, such as whether or not to add calories from alcohol consumption to the model and whether the indicators should be adjusted to the different cultures and specific population groups remain unanswered.

CONCLUSIONS

In order to determine the role of nutrition in social health inequalities, it is important to develop standard indicators that are suitable for monitoring the relationship between dietary recommendations and eating habits.

Food patterns defined by cluster analysis and their utility as dietary exposure variables: a report from the Malmö Diet and Cancer Study

OBJECTIVE

To explore the utility of cluster analysis in defining complex dietary exposures, separately with two types of variables.

DESIGN

: A modified diet history method, combining a 7-day menu book and a 168-item questionnaire, assessed dietary habits. A standardized questionnaire collected information on sociodemographics, lifestyle and health history. Anthropometric information was obtained through direct measurements. The dietary information was collapsed into 43 generic food groups, and converted into variables indicating the per cent contribution of specific food groups to total energy intake. Food patterns were identified by the QUICK CLUSTER procedure in SPSS, in two separate analytical steps using unstandardized and standardized (Z-scores) clustering variables.

SETTING

: The Malmö Diet and Cancer (MDC) Study, a prospective study in the third largest city of Sweden, with baseline examinations from March 1991 to October 1996.

SUBJECTS

A random sample of 2206 men and 3151 women from the MDC cohort (n = 28 098).

RESULTS

Both variable types produced conceptually well separated clusters, confirmed with discriminant analysis. 'Healthy' and 'less healthy' food patterns were also identified with both types of variables. However, nutrient intake differences across clusters were greater, and the distribution of the number of individuals more even, with the unstandardized variables. Logistic regression indicated higher risks of past food habit change, underreporting of energy and higher body mass index (BMI) for individuals falling into 'healthy' food pattern clusters.

CONCLUSIONS

The utility in discriminating dietary exposures appears greater for unstandardized food group variables. Future studies on diet and cancer need to recognize the confounding factors associated with 'healthy' food patterns.

Food intake patterns and gallbladder disease in Mexican Americans

OBJECTIVE

Results of previous studies on diet and gallbladder disease (GBD), defined as having gallstones or having had surgery for gallstones, have been inconsistent. This research examined patterns of food intake in Mexican Americans and their associations with GBD.

DESIGN

Cross-sectional.

SUBJECTS

The study population included 4641 Mexican Americans aged 20-74 years who participated in the 1988-94 third National Health and Nutrition Examination Survey (NHANES III). GBD was diagnosed by ultrasound. Food intake patterns were identified by principal components analysis based on food frequency questionnaire responses. Component scores representing the level of intake of each pattern were categorized into quartiles, and prevalence odds ratios (POR) were estimated relative to the lowest quartile along with 95% confidence intervals (CI).

RESULTS

There were four distinct patterns in women (vegetable, high calorie, traditional, fruit) and three in men (vegetable, high calorie, traditional). After age adjustment, none were associated with GBD in women. However, men in the third (POR = 0.42, 95%CI 0.21-0.85) and fourth (POR = 0.53, 95%CI 0.28-1.01) quartiles of the traditional intake pattern were half as likely to have GBD as those in the lowest quartile.

CONCLUSIONS

These findings add to a growing literature suggesting dietary intake patterns can provide potentially useful and relevant information on diet-disease associations. Nevertheless, methods to do so require further development and validation.

Genetic and environmental influences on eating patterns of twins aged >/=50 y

BACKGROUND

Clinicians and researchers could benefit from a greater understanding of the role of genetic and environmental factors in human eating behavior.

OBJECTIVE

Our aim was to estimate the relative influence of genetic and environmental factors on habitual eating patterns in middle-aged and elderly men and women.

DESIGN

Male and female twins (n = 4640) aged >/=50 y completed a mailed version of the National Cancer Institute food-frequency questionnaire. Factor analysis was performed to identify eating patterns among respondents. Estimates of genetic, common environmental (shared by family members), and specific environmental (unique to an individual) influences were obtained for food use, serving size, and consumption frequency by comparing monozygotic and dizygotic twin-pair groups with structural equation analysis.

RESULTS

Two independent eating patterns were identified: the first consisted of items high in fat, salt, and sugar, and the second reflected healthful eating habits. Although the influence of environmental factors was larger, between 15% and 38% of the total variation in pattern 1 and between 33% and 40% in pattern 2 were explained by genetic influences. Models accounting for sex differences in genetic and environmental estimates fit the data significantly better for food use and serving size of foods in eating pattern 1 and for food use in eating pattern 2.

CONCLUSION

Although 60-85% of the variability in eating patterns was associated with environmental factors, genetic influences were also apparent and there was some evidence of sex specificity. These findings may be important in crafting dietary interventions and predicting adherence to these interventions.

Smoking, diet, and health behaviors among lead-exposed blue-collar workers

The objectives of the study were to compare dietary intake by smoking levels in blue-collar Israeli workers occupationally exposed to lead and thus identify additional areas for health-enhancing intervention in addition to smoking cessation. One hundred and eighty-seven male industrial employees who were exposed to lead through their work were screened at the worksite to evaluate health status and dietary intake. Smokers had higher intakes of fat, cholesterol, calcium, riboflavin, and vitamin E per day. They were consuming more meat and high-fat dairy products. Dose-response relationships were shown for fat and energy intake by smoking level. Thus, smoking is associated with other adverse health behaviors. When conducting epidemiologic or occupational studies, analyses should include adjustment for the fact that the lifestyles of smokers may also be unhealthy in other ways.