The internal validity of a dietary pattern analysis. The Framingham Nutrition Studies

A Structural Equation Modelling Approach to Examine the Mediating Effect of Stress on Diet in Culturally Diverse Women of Childbearing Age

Background: Stress has been shown to be associated with poor nutrition among young women. However, studies around the topic have major limitations in their methodologies and the role of confounding factors within this association remains unclear in the literature. Objective: To investigate the associations between stress and dietary quality/patterns in a culturally diverse population of childbearing-aged women. Methods: A secondary analysis of data from two studies conducted in UK and Lebanon was performed using Structural Equation Modelling (SEM) to explore the role of country context, socio-economic status, and physical variables. Participants were healthy women of childbearing age (n = 493). Variables measured were dietary intake, stress, physical activity, sociodemographic variables, and Body Mass Index. These were included in the SEM analysis to examine the mediating effect of stress. Results: The results showed that, among all variables, only country had a significant effect on dietary quality and patterns through the mediatory effect of stress. Participants from Lebanon were found to have higher stress levels compared to participants from the UK, and this contributed to a lower adherence to a Mediterranean diet. Conclusions: This study shows that for women of childbearing age, having a good diet quality/pattern is dependent on stress levels and country context.

Effects of a brief intervention based on Acceptance and Commitment Therapy versus usual care for cardiac rehabilitation patients with coronary heart disease (ACTonHEART): a randomised controlled trial

OBJECTIVES

The main objective of the study is to investigate the short-term efficacy of Acceptance and Commitment Therapy (ACT) on the simultaneous modification of biological indicators of risk and psychological well-being in patients with coronary heart disease attending cardiac rehabilitation (CR).

DESIGN

This was a two-arm randomised controlled trial comparing a brief, manualised, ACT-based intervention with usual care (UC).

SETTING

The study was conducted in an outpatient CR unit in Italy. Data collection took place from January 2016 to July 2017.

PARTICIPANTS

Ninety-two patients were enrolled and randomised, following an unbalanced randomisation ratio of 2:1 to the ACT group (n=59) and the control group (n=33). Eighty-five patients completed the ACT (n=54) and the UC (n=31) interventions and were analysed.

INTERVENTIONS

The control group received UC, a 6 weeks multidisciplinary outpatient CR programme, encompassing exercise training, educational counselling and medical examinations. The experimental group, in addition to UC, participated in the Acceptance and Commitment Therapy on HEART disease (ACTonHEART) intervention encompassing three group sessions based on ACT.

OUTCOMES

The primary outcomes were Low Density Lipoproteins (LDL)cholesterol, resting systolic blood pressure, body mass index (BMI) and psychological well-being measured by the Psychological General Well-Being Index (PGWBI). Outcome measures were assessed at baseline and at the end of CR.

RESULTS

Based on linear mixed models, no significant group × time interaction was observed for either the primary outcomes (β, 95% CI: PGWBI =-1.13, -6.40 to -4.14; LDL cholesterol =-2.13, -11.02 to -6.76; systolic blood pressure =-0.50, -10.76 to -9.76; diastolic blood pressure =-2.73, -10.12 to -4.65; BMI =-0.16, -1.83 to -1.51, all p values >0.05) or the secondary outcomes (all p values >0.05). A significant time effect was found for the PGWBI total (beta=4.72; p=0.03).

CONCLUSIONS

Although analyses revealed null findings, the results can inform the design of future ACT-based CR interventions and can help researchers to strike a balance between the idealised implementation of an ACT intervention and the structural limitations of existing CR programmes.

TRIAL REGISTRATION NUMBER

NCT01909102.

Dietary patterns of 5-year-old children and their correlates: findings from a multi-ethnic Asian cohort

There is limited data on the dietary patterns of 5-year-old children in Asia. The study examined childhood dietary patterns and their maternal and child correlates in a multi-ethnic Asian cohort. Based on caregiver-reported 1-month quantitative FFQ of 777 children from the Growing Up in Singapore Towards healthy Outcomes cohort, cluster analysis identified two mutually exclusive clusters. Children in the 'Unhealthy' cluster (43·9 %) consumed more fries, processed meat, biscuits and ice cream, and less fish, fruits and vegetables compared with those in the 'Healthy' cluster (56·1 %). Children with mothers of lower educational attainment had twice the odds of being assigned to the 'Unhealthy' cluster (adjusted OR (95 % CI) = 2·19 (95 % CI 1·49-3·24)). Children of Malay and Indian ethnicities had higher odds of being assigned to the 'Unhealthy' cluster (adjusted OR = 25·46 (95 % CI 15·40, 42·10) and 4·03 (95 % CI 2·68-6·06), respectively), relative to Chinese ethnicity. In conclusion, this study identified two dietary patterns in children, labelled as the 'Unhealthy' and 'Healthy' clusters. Mothers' educational attainment and ethnicity were two correlates that were associated with the children's assignments to the clusters. These findings can assist in informing health promotion programmes targeted at Asian children.

'Energy-Dense, High-SFA and Low-Fiber' Dietary Pattern Lowered Adiponectin but Not Leptin Concentration of Breast Cancer Survivors

Dietary pattern (DP) and its relationship with disease biomarkers have received recognition in nutritional epidemiology investigations. However, DP relationships with adipokines (i.e., adiponectin and leptin) among breast cancer survivors remain unclear. Therefore, we assessed relationships between DP and high-molecular weight (HMW) adiponectin and leptin concentration among breast cancer survivors. This cross-sectional study involved 128 breast cancer survivors who attended the oncology outpatient clinic at two main government hospitals in the East Coast of Peninsular Malaysia. The serum concentration of HMW adiponectin and leptin were measured using enzyme-linked immunosorbent assay (ELISA) kits. A reduced rank regression method was used to analyze DP. Relationships between DP with HMW adiponectin and leptin were examined using regression models. The findings show that with every 1-unit increase in the ‘energy-dense, high-SFA, low-fiber’ DP z-score, there was a reduction by 0.41 μg/mL in HMW adiponectin which was independent of age, BMI, education level, occupation status, cancer stage, and duration since diagnosis. A similar relationship with leptin concentration was not observed. In conclusion, the ‘energy-dense, high-saturated fat and low-fiber’ DP, which is characterized by high intake levels of sugar-sweetened drinks and fat-based spreads but low intake of fruits and vegetables, is an unhealthy dietary pattern and unfavorable for HMW adiponectin concentration, but not for leptin. These findings could serve as a basis in developing specific preventive strategies that are tailored to the growing population of breast cancer survivors.

Maternal diet patterns during early pregnancy in relation to neonatal outcomes

BACKGROUND

Research has established that maternal diet influences fetal growth and preterm birth, but most studies only evaluate single nutrients. Relations between dietary patterns and neonatal outcomes are understudied.

OBJECTIVE

We evaluated associations of neonatal outcomes with maternal diet patterns derived using 3 a priori diet scores [Alternative Healthy Eating Index-2010 (AHEI-2010), alternate Mediterranean diet score (aMed), and Dietary Approaches to Stop Hypertension (DASH)] as well as principal components analysis (PCA).

METHODS

We studied 1948 women from the Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies-Singletons, a racially diverse multisite cohort of pregnant women in the USA (2009-2013). Diet in the past 3 mo was assessed using a self-administered FFQ at 8-13 weeks of gestation. Birthweight was abstracted from medical records and neonatal anthropometry measured postdelivery using standardized protocols.

RESULTS

All 3 a priori scores were significantly associated with increased birthweight, and aMed was also associated with reduced odds of low birthweight [quartile 4 versus 1: ORadj = 0.42; 95% CI: 0.18, 1.00 (P-trend = 0.02)]. Greater aMed and DASH scores were significantly associated with increased length [aMed: quartile 4 versus 1: 0.54 cm; 95% CI: 0.10, 0.99 (P-trend = 0.006); DASH: quartile 4 versus 1: 0.62 cm; 95% CI: 0.25, 0.99 (P-trend = 0.006)] and upper arm length. Neither diet pattern derived from PCA was significantly associated with birthweight.

CONCLUSION

Among mostly low-risk pregnant women, pre- and early pregnancy healthful diet quality indices, particularly the aMed score, were associated with larger neonatal size across the entire birthweight distribution. In the absence of generally accepted pregnancy-specific diet quality scores, these results provide evidence for an association between maternal diet patterns and neonatal outcomes.

Secular trend in dietary patterns of Iranian adults from 2006 to 2017: Tehran lipid and glucose study

BACKGROUND

Based on data regarding nutrition transition in the Middle East and North Africa, this study aim to investigate the general structure and secular trend of dietary patterns reported from the Tehran Lipid and Glucose Study (TLGS) and adherence to these dietary patterns among Iranian population from 2006 till 2017.

METHODS

We investigated on four examination waves of TLGS, including wave 1 (2006-2008), wave 2 (2009-2011), wave 3 (2012-2014), and wave 4 (2015-2017), using a validated and reliable food frequency questionnaire. Generalized Estimating Equations was used to assess secular trends in anthropometric, biochemical, and dietary variables across the study period. To identify general structure and secular trend of dietary patterns during each waves, principle component analysis (PCA) and K-mean cluster analysis were used, respectively.

RESULTS

After adjusting for potential confounders including age, sex, body mass index, and total energy intake, the carbohydrate and protein intake gradually increased and the total fat intake decreased during study period (P-value< 0.001), although total energy intake remained stable. During the study period, participants consumed noticeably less refined grains, solid fat, dairy products, and simple sugars. Snack and dessert consumption increased and meat intakes showed no significant changes during a decade (all P-values< 0.001). Three dietary patterns extracted using PCA, included: Healthy dietary pattern characterized by higher intakes of vegetable, fruit, dairy products, liquid oil, nuts and seeds, and honey and jam; Western dietary pattern featured by refined grain, solid fat, meat, snack and dessert, potato, and soft drink, and the Mixed dietary pattern, highlighted by tea and coffee, and simple sugar. Based on cluster analysis, 27.8% of participants in wave 4 followed a Western dietary pattern, and 34.1% followed the Mixed dietary pattern. The Healthy dietary pattern was stable among the study population during the last decade.

CONCLUSIONS

The structure and the type of foods that participants preferred to eat changed since 2006, a new secular trend in dietary patterns, including a stability of Healthy dietary pattern, a decline of the Western dietary pattern and an increase in the Mixed dietary pattern was obsereved in our investigation.

A Priori and a Posteriori Dietary Patterns in Women of Childbearing Age in the UK

Poor diet quality is a major cause of maternal obesity. We aimed to investigate a priori and a-posteriori derived dietary patterns in childbearing-aged women in UK. An online survey assessed food intake, physical activity (PA), anthropometry and socio-demographics. An a priori defined diet quality was determined via Mediterranean diet (MD) adherence score and Exploratory Factor Analysis (EFA) derived dietary patterns (DPs). Multiple linear regression explored associations between DPs with anthropometric measures, PA and socio-demographics. Participants (n = 123) had low-to-medium MD adherence (average MD-score: 4.0 (2.0)). Age was positively associated with higher MD adherence (X2 (2) = 13.14, p = 0.01). EFA revealed three DPs: 'fruits, nuts, vegetables and legumes' ("Vegetarian-style" DP); 'sweets, cereals, dairy products and potatoes' ("Dairy, sweets and starchy foods" DP); and 'eggs, seafood and meats' ("Protein-rich" DP). "Vegetarian-style" DP was positively associated with higher maternal educational level (p < 0.01) and PA (p = 0.01), but negatively with white ethnicity (p < 0.01). "Dairy, sweets and starchy foods" DP was positively associated with white ethnicity (p = 0.03) and negatively with age (p = 0.03). "Protein-rich" DP was positively associated with age (p < 0.001) and negatively with PA (p = 0.01). A poor diet quality was found among childbearing-aged women; notably in the younger age category, those of white ethnicity, that were more physically inactive and with a lower socioeconomic background.

Ethnic differences in maternal diet in pregnancy and infant eczema

BACKGROUND

The global prevalence of childhood eczema has increased over the last few decades, with a marked increase in high-income countries. Differences in prevalence of childhood eczema between countries and ethnicities suggest that genetic and early modifiable environmental factors, such as dietary intake, may underlie this observation. To investigate the association between pregnancy diet and infant eczema in a consortium of prospective Canadian birth cohorts predominantly comprised of white Europeans and South Asians.

METHODS

We evaluated the association of maternal dietary patterns reported during pregnancy (assessed at 24-28 weeks gestation using a semi-quantitiative food-frequency questionnaire) with parent-reported physician-diagnosed infant eczema at 1-year from 2,160 mother-infant pairs. Using three dietary patterns ("Western", "plant-based", and "Balanced") previously derived in this cohort using principal component analysis, we used multivariable logistic regression to determine the association of these dietary patterns with infant eczema, adjusted for potential confounders.

RESULTS

We observed a lower odds of eczema in the full sample combining white Europeans and South Asians with greater adherence to a plant-based (OR = 0.65; 95% CI: 0.55, 0.76; <0.001) and Western dietary pattern (OR = 0.73; 95% CI: 0.60, 0.89; P<0.01), after adjusting for other known predictors of eczema, including ethnicity, which was not significant. No associations were observed for the balanced diet. An interaction between the Western diet and ethnicity was observed (P<0.001). Following stratification by ethnicity, a protective association between the plant-based diet and infant eczema was confirmed in both white Europeans (OR = 0.59; 95% CI: 0.47, 0.74; P<0.001) and South Asians (OR = 0.77; 95% CI: 0.61, 0.97; P = 0.025). In white Europeans only, a Western diet was associated with a lower odds of infant eczema (OR = 0.69; 95% CI: 0.56, 0.87; P = 0.001) while a balanced diet increased the odds of infant eczema (OR = 1.23; 95% CI: 1.02, 1.49; P = 0.03). Beyond a plant-based diet, no significant associations with other dietary patterns were observed in South Asians.

CONCLUSION

A plant-based diet during pregnancy is associated with a lowered odds of infant eczema at 1 year in all participants. Future studies of the components of plant-based diet which underlie the lower risk of eczema are needed.

Using Cluster Analysis to Identify Subgroups of College Students at Increased Risk for Cardiovascular Disease

BACKGROUND AND PURPOSE

 To examine the co-occurrence of cardiovascular risk factors and cluster subgroups of college students for cardiovascular risks.

METHODS

A cross sectional descriptive study was conducted using co-occurrence patterns and hierarchical clustering analysis in 158 college students.

RESULTS

The top co-occurring cardiovascular risk factors were overweight/obese and hypertension (10.8%, n = 17). Of the total 34 risk factors that co-occurred, 30 of them involved being overweight/obese. A six-cluster-solution was obtained, two clusters displayed elevated levels of lifetime and 30-year cardiovascular disease risks.

CONCLUSIONS

The hierarchical cluster analysis identified that single White males with a family history of heart disease, overweight/obese, hypertensive or diabetes, and occasionally (weekly) consumed red meat, take antihypertensive medication, and hyperlipidemia were considered the higher risk group compared to other subgroups.

College Students' Perception of Current and Projected 30-Year Cardiovascular Disease Risk Using Cluster Analysis with Internal Validation

Cardiovascular risk factors in young adults at a national level are less than ideal specifically for hypercholesterolemia, hypertension, and diabetes. Explore college students' perception of their 30-year cardiovascular disease (CVD) risk using cluster analysis technique with internal validation. This is a descriptive and cross-sectional study. A total of 133 college students, aged 20-36 with no known history of CVD, were recruited and used to perform cluster analysis with internal validation. The mean age of the sample was 24.85 and predominately female (59.5%). The mean score for perception of cardiovascular risk factors was 21.20 ranging from 12 to 34 points on a Likert scale. The mean score for the 30-year CVD risk assessment was 5.23 ranging from 1 to 22%. Five clusters emerged from the cluster analysis. However, two of the clusters, the highest risk with moderate perception and low risk and lowest perception, were identified as areas for potential intervention as there were discrepancies between subjects' perceived risk and their actual 30-year risk. The national data and literature has indicated a lack of awareness of CVD risk among this population which our study also concurred. Identifying the discrepancies between the perceived and projected CVD risk are useful for researchers and clinicians such as nurses to take the initiative to focus on and begin to intervene in this population to reduce potential adverse events of CVD.

Hypothesis and data-driven dietary patterns and colorectal Cancer survival: findings from Newfoundland and Labrador colorectal Cancer cohort

Background

Dietary patterns are commonly used in epidemiological research, yet there have been few studies assessing if and how research results may vary across dietary patterns. This study aimed to estimate the risk of mortality/recurrence/metastasis using different dietary patterns and comparison amongst the patterns.

Methods

Dietary patterns were identified by Cluster Analysis (CA), Principal Component Analysis (PCA), Alternate Mediterranean Diet score (altMED), Recommended Food Score (RFS) and Dietary Inflammatory Index (DII) scores using a 169-item food frequency questionnaire.

Five hundred thirty-two colorectal cancer patients diagnosed between 1999 and 2003 in Newfoundland were followed-up until 2010. Overall Mortality (OM) and combined Mortality, Recurrence or Metastasis (cMRM) were identified. Comparisons were made with adjusted Cox proportional Hazards Ratios (HRs), correlation coefficients and the distributions of individuals in defined clusters by quartiles of factor and index scores.

Results

One hundred and seventy cases died from all causes and 29 had a cancer recurrence/metastasis during follow-up. Processed meats as classified by PCA (HR 1.82; 95% confidence interval (CI) 1.07–3.09), clusters characterized by meat and dairy products (HR 2.19; 95% CI 1.03–4.67) and total grains, sugar, soft drinks (HR 1.95; 95% CI 1.13–3.37) were associated with a higher risk of cMRM. Poor adherence to AltMED increased the risk of all-cause OM (HR 1.62; 95% CI 1.04–2.56). Prudent vegetable, high sugar pattern, RFS and DII had no significant association with both OM and cMRM.

Conclusion

Estimation of OM and cMRM varied across dietary patterns which is attributed to the differences in the foundation of each pattern.

Electronic supplementary material

The online version of this article (10.1186/s12937-018-0362-x) contains supplementary material, which is available to authorized users.

Patterns of Protein Food Intake Are Associated with Nutrient Adequacy in the General French Adult Population

Protein food intake appears to partially structure dietary patterns, as most current emergent diets (e.g., vegetarian and flexitarian) can be described according to their levels of specific protein sources. However, few data are available on dietary protein patterns in the general population and their association with nutrient adequacy. Based on protein food intake data concerning 1678 adults from a representative French national dietary survey, and non-negative-matrix factorization followed by cluster analysis, we were able to identify distinctive dietary protein patterns and compare their nutrient adequacy (using PANDiet probabilistic scoring). The findings revealed eight patterns that clearly discriminate protein intakes and were characterized by the intakes of one or more specific protein foods: ‘Processed meat’, ‘Poultry’, ‘Pork’, ‘Traditional’, ‘Milk’, ‘Take-away’, ‘Beef’ and ‘Fish’. ‘Fish eaters’ and ‘Milk drinkers’ had the highest overall nutrient adequacy, whereas that of ‘Pork’ and ‘Take-away eaters’ was the lowest. Nutrient adequacy could often be accounted for by the characteristics of the food contributing to protein intake: ‘Meat eaters’ had high probability of adequacy for iron and zinc, for example. We concluded that protein patterns constitute strong elements in the background structure of the dietary intake and are associated with the nutrient profile that they convey.

Association between dietary protein intake and type 2 diabetes varies by dietary pattern

BACKGROUND

Epidemiological studies have demonstrated that high total protein intake was related to type 2 diabetes mellitus (T2DM) risks. However, few studies considered the impact of dietary pattern.

OBJECTIVE

We examined the associations between protein intake and T2DM in different dietary patterns.

METHODS

We used the demographic and dietary information of adults aged 18-75 years from the China Health and Nutrition Survey (2009), consisting of 4113 women and 4580 men. Dietary data was collected by using 24-h recalls combined with a food inventory for 3 consecutive days. Cluster analysis was used to classify subjects into groups, as determined by major sources of protein. Logistic regression models were used to calculate odds ratios (OR) and 95% confidence interval (95% CI) of T2DM according to the energy-adjusted protein intake.

RESULTS

All participants were divided into three patterns according to the dietary source of protein (legumes and seafood, red meat, refined grains). Overall, plant protein intake was significantly and inversely associated with T2DM. In the subgroup analysis by dietary patterns, extreme quartile of plant protein intake was also inversely related to T2DM in the "legumes and seafood" group [OR = 0.58, 95% CI (0.33-0.96)]. Total protein intake and animal protein intake were positively related to T2DM in the "red meat" group [OR: 3.12 (1.65-5.91) and 3.48 (1.87-6.60), respectively]. However, the association of animal protein intake was reversed in the "refined grains" group [OR = 0.55, 95% CI 0.32-0.89].

CONCLUSIONS

The association between protein intake and T2DM varies by dietary pattern. Dietary pattern may be considered into the recommendation of protein intake for diabetes prevention.

Sociodemographic factors are associated with dietary patterns in Mexican schoolchildren

OBJECTIVE

Childhood obesity has increased rapidly in Mexico, along with changes in the food environment. However, little is known about the dietary patterns (DP) of Mexican children. We aimed to characterize the DP of schoolchildren and to analyse their associations with sociodemographic factors.

DESIGN

Cross-sectional analysis. Dietary and sociodemographic information was obtained, including a single 24 h recall, socio-economic status (SES), geographic region, area of residence and ethnicity. DP were defined with cluster analysis (using k-means). Multinomial logistic regression models, adjusted for the survey design, were used to assess associations between DP and sociodemographic variables.

SETTING

2012 Mexican National Health and Nutrition Survey (ENSANUT-2012).

SUBJECTS

Schoolchildren (n 2751) aged 5-11 years who participated in ENSANUT-2012.

RESULTS

Four DP were identified: 'Traditional', 'Industrialized', 'Varied' and 'Modern'. Reported energy intake (mean (sd)) was lowest in the 'Traditional' and highest in the 'Industrialized' DP (7037 (3707) kJ/d (1682 (886) kcal/d) v. 8427 (3753) kJ/d (2014 (897) kcal/d), respectively, P<0·05). Significant differences in fat and fibre intakes were seen across DP. Non-indigenous v. indigenous children were 22·0 times (95 % CI 5·1, 93·6) more likely to have a 'Modern' rather than 'Traditional' DP. Relative likelihood of having an 'Industrialized' rather than 'Traditional' DP was 6·2 (95 % CI 3·9, 9·9) among schoolchildren from high SES v. low SES.

CONCLUSIONS

Among Mexican schoolchildren, DP were associated with sociodemographic variables. Non-indigenous children were significantly more likely to consume a 'Modern' than a 'Traditional' DP. Children with higher SES were more likely to have an 'Industrialized' pattern. It is necessary to consider dietary characteristics in the different sociodemographic strata when dietary interventions are designed.

Dietary patterns: a literature review of the methodological characteristics of the main step of the multivariate analyzes

OBJECTIVE

To describe the solutions adopted in the multiple steps of the use of multivariate techniques to obtain a dietary pattern (DP) concerning: the objective of the studies, the selection of the method for measuring food intake, the criteria for grouping the foods, the number of food groups used, the number of DP obtained, and the nomenclature criteria.

METHODS

The articles were selected from MEDLINE and Lilacs scientific databases using the following keywords: "dietary patterns" versus "factor analysis"; "principal components analysis"; "cluster analysis" and "reduced regression rank." The initial search resulted in 1,752 articles. After inclusion and exclusion criteria, 189 publications were selected.

RESULTS

The following aspects were relevant among the studies: the prevalence of the principal component analysis (PCA); the prevalence of the use of 4 to 5 DPs in the studies of association with health outcomes; the use of 30 or more food groups from the food frequency questionnaire (FFQ); the prevalence of studies that associated DPs with health outcomes and socioeconomic factors; and the heterogeneity of criteria used throughout the analytical stages of the multivariate techniques.

CONCLUSION

The heterogeneity between the publications concentrates on the criteria for food grouping, the nomenclature, and the number of dietary patterns calculated, which varied depending on the number of food groups present in these analyses. To understand, apply, and explore in full, the multivariate techniques has become necessary in order to improve the reliability of the results and, consequently, to improve the relationships with health outcomes and socioeconomic factors.

Dietary Patterns and Cardio-metabolic Risk in a Population of Guatemalan Young Adults

Background

Latin America is facing an increasing burden of nutrition-related non-communicable disease. Little is known about dietary patterns in Guatemalan adults and how dietary patterns are associated with cardio-metabolic disease (CMD) risk.

Methods

This analysis is based on data from a 2002–04 follow-up study of the INCAP Nutrition Supplementation Trial Longitudinal Cohort. Diet data were collected using a validated, semi-quantitative food frequency questionnaire. We derived dietary patterns using principal components analysis. CMD risk was assessed by anthropometry (body mass index, waist circumference), biochemistry (fasting blood glucose and lipids), and clinical (blood pressure) measures. We used sex-stratified multivariable log binomial models to test associations between dietary pattern tertile and CMD risk factors. The sample included 1428 participants (681 men and 747 women) ages 25–43 years.

Results

We derived three dietary patterns (traditional, meat-based modern, and starch-based modern), collectively explaining 24.2% of variance in the diet. Dietary patterns were not associated with most CMD risk factors; however, higher starch-based modern tertiles were associated with increased prevalence of low highdensity lipoprotein cholesterol (HDL-c) in men (Prevalence Ratio (PR) 1.17, 95% Confidence Interval (CI) 1.01, 1.20 for tertile 2; PR 1.20, 95% CI 1.00, 1.44 for tertile 3; p trend 0.04). Higher traditional tertiles were associated with increased prevalence of abdominal obesity in women (PR 1.24, 95% CI 1.07, 1.43 for tertile 2; PR 1.19, 95% CI 1.02, 1.39 for tertile 3; p trend 0.02) but marginally significant reduced prevalence of low HDL-c in men (PR 0.88, 95% CI 0.76, 1.00 for tertile 2; PR 0.85, 95% CI 0.72, 1.00 for tertile 3; p trend 0.05).

Conclusion

Our findings suggest the presence of two ‘modern' dietary patterns in Guatemala – one of which was associated with increased prevalence of low HDL-c in men. The association between the traditional dietary pattern and some CMD risk factors may vary by sex.

Electronic supplementary material

The online version of this article (doi:10.1186/s40795-017-0188-5) contains supplementary material, which is available to authorized users.

Dietary Patterns Among Overweight and Obese African-American Women Living in the Rural South

INTRODUCTION

Obesity and chronic diseases disproportionately affect African-American women in the rural South (US) and may be influenced by adherence to a typical Southern-style diet. There is a need to examine dietary patterns of this population and to determine if consumption of nutritionally rich foods like nuts is associated with consumption of other nutritious foods. The objectives of this study were to identify (1) dietary patterns of overweight/obese African-American women in the rural South; (2) the role that nuts play in the diet; (3) and adherence to federal food group recommendations across dietary patterns.

METHODS

Secondary data analysis of two baseline 24-h dietary recalls was performed on 383 overweight/obese African-American women enrolled in a weight loss intervention in Alabama and Mississippi between 2011 and 2013. Cluster analysis identified dietary patterns. t tests and chi-square tests tested demographic and dietary differences across clusters. The proportion of women in each cluster who met federal recommendations for fruit, vegetable, nuts, added sugar, and sodium intake was calculated.

RESULTS

Two dietary patterns were found. Nut intake frequency was higher in cluster 2 (P < .001), which was characterized by a higher intake frequency of fruits and vegetables, but high mean daily intake of added sugar (12.26 ± 7.67 tsp) and sodium (2800 ± 881 mg). Ninety-two percent of participants in this cluster consumed red/processed meats daily.

CONCLUSION

Even among women in this population who consume a more plant-based dietary pattern containing nuts, there is still a need to decrease intake of added sugar, sodium, and red meat.

Dietary protein is associated with musculoskeletal health independently of dietary pattern: the Framingham Third Generation Study

Background: Above-average dietary protein, as a single nutrient, improves musculoskeletal health. Evaluating the link between dietary protein and musculoskeletal health from a whole-diet perspective is important, as dietary guidelines focus on dietary patterns.Objective: We examined the prospective association of novel dietary protein food clusters (derived from established dietary pattern techniques) with appendicular lean mass (ALM), quadriceps strength (QS), and bone mineral density (BMD) in 2986 men and women, aged 19-72 y, from the Framingham Third Generation Study.Design: Total protein intake was estimated by food-frequency questionnaire in 2002-2005. A cluster analysis was used to classify participants into mutually exclusive groups, which were determined by using the percentage of contribution of food intake to overall protein intake. General linear modeling was used to 1) estimate the association between protein intake (grams per day) and BMD, ALM, appendicular lean mass normalized for height (ALM/ht²), and QS (2008-2011) and to 2) calculate adjusted least-squares mean outcomes across quartiles of protein (grams per day) and protein food clusters.Results: The mean ± SD age of subjects was 40 ± 9 y; 82% of participants met the Recommended Daily Allowance (0.8 g · kg body weight^-1 · d^-1). The following 6 dietary protein food clusters were identified: fast food and full-fat dairy, fish, red meat, chicken, low-fat milk, and legumes. BMD was not different across quartiles of protein intake (P-trend range = 0.32-0.82); but significant positive trends were observed for ALM, ALM/ht² (P < 0.001), and QS (P = 0.0028). Individuals in the lowest quartile of total protein intake (quartile 1) had significantly lower ALM, ALM/ht², and QS than did those in the higher quartiles of intake (quartiles 2-4; (P ranges = 0.0001-0.003, 0.0007-0.003, and 0.009-0.05, respectively). However, there were no associations between protein clusters and any musculoskeletal outcome in adjusted models.Conclusions: In a protein-replete cohort of adults, dietary protein is associated with ALM and QS but not with BMD. In this study, dietary protein food patterns do not provide further insight into beneficial protein effects on muscle outcomes.

Development of a Novel Six-Month Nutrition Intervention for a Randomized Trial in Older Men with Mobility Limitations

OBJECTIVES

Nutrition impacts the development of sarcopenia and protein intake is an important modulator of skeletal muscle mass loss in older people. The Optimizing Protein Intake in Older Men with Mobility Limitation (OPTIMEN) Trial was designed to assess the independent and combined effects of higher protein intake and a promyogenic agent, testosterone, on lean body mass, muscle strength and physical function in older men with mobility disability. The purpose of this paper is to describe the experimental design and nutrition intervention, including techniques used by research dietitians to develop and deliver energy and protein-specific meals to the homes of community-dwelling participants. Strategies to enhance long-term dietary compliance are detailed.

DESIGN

Randomized, double-blind, placebo-controlled six-month intervention trial.

SETTING

Participants were recruited from Boston MA USA and surrounding communities.

PARTICIPANTS

Older men who were mobility-limited (Short Physical Performance Battery (SPPB) 3-10) and consuming less protein (<0.83 g/kg/day) were recruited for this study.

INTERVENTION

Here we report the successful implementation of a double-blind, placebo-controlled, parallel group, randomized controlled trial with a 6-month intervention period among community-living men, age 65 years and older with a mobility limitation. A controlled feeding plan was used to deliver required energy intakes and prescribed protein quantities of 0.8 or 1.3 grams/kilogram/day (g/kg/d) in three meals plus snacks and supplements. A 2x2 factorial design was used to assess the effects of protein level alone and in combination with testosterone (vs. placebo) on changes in lean body mass (primary outcome), muscle strength, and physical function.

RESULTS

A total of 154 men met the eligibility criteria; 112 completed a 2-week run-in period designed to evaluate compliance with the nutrition intervention. Of these, 92 subjects met compliance eligibility criteria and agreed to be randomized; 85% completed the full trial. The study successfully delivered three meals per day to subjects, with a high degree of compliance and subject satisfaction. Overall self-reported compliance rates were 80% and 93% for the meals and supplements, respectively. Details of compliance strategies are discussed.

CONCLUSION

This community-based study design may serve as a model for longer-term nutritional interventions requiring monitoring of dietary compliance in a home-based feeding and supplementation trial.

Bone Mineral Density and Protein-Derived Food Clusters from the Framingham Offspring Study

BACKGROUND

Dietary protein is beneficial to bone health; however, dietary patterns of protein intake and their relationship with bone mineral density (BMD) have not been evaluated.

OBJECTIVE

To examine the relationship of dietary protein food clusters with BMD at the femoral neck, trochanter, total femur, and lumbar spine among middle-aged and older men and women.

DESIGN

Cross-sectional study.

PARTICIPANTS AND SETTING

Two thousand seven hundred fifty-eight community-dwelling individuals from the Framingham Offspring Study.

METHODS

BMD was measured by Lunar DPX-L (Lunar Radiation Corporation) in 1996-2001. Dietary intakes were estimated using the Willett food frequency questionnaire in either 1995-1998 or 1998-2001, and the exam closest to a participant's BMD measurement was used. Cluster analysis (FASTCLUS procedure, k-means method) was used to classify participants into groups, determined by major sources of protein. Generalized linear regression was used to compare adjusted least-squares mean BMD across protein food clusters for all pairwise comparisons.

RESULTS

From 2,758 participants (44% men; mean age 61±9 years, range=29 to 86 years), five protein food clusters were identified (chicken, fish, processed foods, red meat, and low-fat milk). Three of these food clusters showed associations with BMD. The red meat protein food cluster presented with significantly lower femoral neck BMD compared with the low-fat milk cluster (red meat 0.898±0.005 g/cm(2) vs low-fat milk 0.919±0.007 g/cm(2); P=0.04). Further, the processed foods protein cluster presented with significantly lower femoral neck BMD compared with the low-fat milk cluster (processed foods 0.897±0.004 g/cm(2) vs low-fat milk 0.919±0.007 g/cm(2); P=0.02). A similar, yet nonsignificant, trend was observed for other BMD sites examined.

CONCLUSIONS

Diets with the greatest proportion of protein intake from red meat and processed foods may not be as beneficial to the skeleton compared with dietary patterns where the highest proportion of protein is derived from low-fat milk.

Effect of energy under-reporting on secular trends of dietary patterns in a mediterranean population

BACKGROUND

Diet is an important factor in the prevention of chronic diseases. Analysis of secular trends of dietary patterns can be biased by energy under-reporting. Therefore, the objective of the present study was to analyse the impact of energy under-reporting on dietary patterns and secular trends in dietary patterns defined by cluster analysis.

DESIGN AND METHODS

Two cross-sectional population-based surveys were conducted in Spain, in 2000 and 2005, with 3058 and 6352 participants, respectively, aged 25 to 74 years. Validated questionnaire was used to collect dietary data. Cluster analysis was run separately for all participants, plausible energy reporters (PER), and energy under-reporters (EUR) to define dietary patterns.

RESULTS

Three clusters, "healthy", "mixed" and "western", were identified for both surveys. The "mixed" cluster was the predominant cluster in both surveys. Excluding EUR reduced the proportion of the "mixed" cluster up to 6.40% in the 2000 survey; this caused secular trend increase in the prevalence of the "mixed" pattern. Cross-classification analysis of all participants and PER' data showed substantial agreement in cluster assignments: 68.7% in 2000 and 84.4% in 2005. Excluding EUR did not cause meaningful (≥ 15%) changes in the "healthy" pattern. It provoked changes in consumption of some food groups in the "mixed" and "western" patterns: mainly decreases of unhealthy foods within the 2000 and increases of unhealthy foods within the 2005 surveys. Secular trend effects of EUR were similar to those within the 2005 survey. Excluding EUR reversed the direction of secular trends in consumption of several food groups in PER in the "mixed" and "western" patterns.

CONCLUSIONS

EUR affected distribution of participants between dietary patterns within and between surveys, secular trends in food group consumption and amount of food consumed in all, but not in the "healthy" pattern. Our findings emphasize threats from energy under-reporting in dietary data analysis.

A posteriori dietary patterns: how many patterns to retain?

Principal component analysis (PCA) and cluster analysis are used frequently to derive dietary patterns. Decisions on how many patterns to extract are primarily based on subjective criteria, whereas different solutions vary in their food-group composition and perhaps association with disease outcome. Literature on reliability of dietary patterns is scarce, and previous studies validated only 1 preselected solution. Therefore, we assessed reliability of different pattern solutions ranging from 2 to 6 patterns, derived from the aforementioned methods. A validated food frequency questionnaire was administered at baseline (1993-1997) to 39,678 participants in the European Prospective Investigation into Cancer and Nutrition-The Netherlands (EPIC-NL) cohort. Food items were grouped into 31 food groups for dietary pattern analysis. The cohort was randomly divided into 2 halves, and dietary pattern solutions derived in 1 sample through PCA were replicated through confirmatory factor analysis in sample 2. For cluster analysis, cluster stability and split-half reproducibility were assessed for various solutions. With PCA, we found the 3-component solution to be best replicated, although all solutions contained ≥1 poorly confirmed component. No quantitative criterion was in agreement with the results. Associations with disease outcome (coronary heart disease) differed between the component solutions. For all cluster solutions, stability was excellent and deviations between samples was negligible, indicating good reproducibility. All quantitative criteria identified the 2-cluster solution as optimal. Associations with disease outcome were comparable for different cluster solutions. In conclusion, reliability of obtained dietary patterns differed considerably for different solutions using PCA, whereas cluster analysis derived generally stable, reproducible clusters across different solutions. Quantitative criteria for determining the number of patterns to retain were valuable for cluster analysis but not for PCA. Associations with disease risk were influenced by the number of patterns that are retained, especially when using PCA. Therefore, studies on associations between dietary patterns and disease risk should report reasons to choose the number of retained patterns.

The ACTonHEART study: rationale and design of a randomized controlled clinical trial comparing a brief intervention based on Acceptance and Commitment Therapy to usual secondary prevention care of coronary heart disease

BACKGROUND

Modifiable risk factors, including life-style habits and psychological variables, have been increasingly demonstrated to have an important role in influencing morbidity and mortality in cardiovascular patients, and to account for approximately 90% of the population risk for cardiac events.Acceptance and Commitment Therapy (ACT) has shown effectiveness in promoting healthy behaviors, and improving psychological well-being in patients with chronic physical conditions. Moreover, a first application of an acceptance-based program in cardiac patients has revealed high treatment satisfaction and initial evidences of effectiveness in increasing heart-healthy behaviour. However, no clinical trial to date has evaluated the efficacy of an acceptance-based program for the modification of cardiovascular risk factors and the improvement of psychological well-being, compared to usual secondary prevention care.

METHODS

Approximately 168 patients will be recruited from an outpatient cardiac rehabilitation unit and randomly assigned to receive usual care or usual care + a brief ACT-based intervention. The ACT group will be administered five group therapy sessions integrating educational topics on heart-healthy behaviours with acceptance and mindfulness skills. Participants will be assessed at baseline, six weeks later (post treatment for the ACT condition), at six and twelve months follow-up.A partially-nested design will be used to balance effects due to clustering of participants into small therapy groups. Primary outcome measures will include biological indicators of cardiovascular risk and self-reported psychological well-being. Treatment effects will be tested via multilevel modeling after which the mediational role of psychological flexibility will be evaluated.

DISCUSSION

The ACTonHEART study is the first randomized clinical trial designed to evaluate the efficacy of a brief group-administered, ACT-based program to promote health behavior change and psychological well-being among cardiac patients. Results will address the effectiveness of a brief treatment created to simultaneously impact multiple cardiovascular risk factors. Conducted in the context of clinical practice, this trial will potentially offer empirical support to alternative interventions to improve quality of life and reduce mortality and morbidity rates among cardiac patients.

TRIAL REGISTRATION

clinicaltrials.gov/ (NCT01909102).

Evaluation of methodologies for assessing the overall diet: dietary quality scores and dietary pattern analysis

This paper aims to describe different approaches for studying the overall diet with advantages and limitations. Studies of the overall diet have emerged because the relationship between dietary intake and health is very complex with all kinds of interactions. These cannot be captured well by studying single dietary components. Three main approaches to study the overall diet can be distinguished. The first method is researcher-defined scores or indices of diet quality. These are usually based on guidelines for a healthy diet or on diets known to be healthy. The second approach, using principal component or cluster analysis, is driven by the underlying dietary data. In principal component analysis, scales are derived based on the underlying relationships between food groups, whereas in cluster analysis, subgroups of the population are created with people that cluster together based on their dietary intake. A third approach includes methods that are driven by a combination of biological pathways and the underlying dietary data. Reduced rank regression defines linear combinations of food intakes that maximally explain nutrient intakes or intermediate markers of disease. Decision tree analysis identifies subgroups of a population whose members share dietary characteristics that influence (intermediate markers of) disease. It is concluded that all approaches have advantages and limitations and essentially answer different questions. The third approach is still more in an exploration phase, but seems to have great potential with complementary value. More insight into the utility of conducting studies on the overall diet can be gained if more attention is given to methodological issues.

Dietary Patterns and the Metabolic Syndrome in Obese and Non-obese Framingham Women**

OBJECTIVES

To examine the relationship between habitual dietary patterns and the metabolic syndrome (MetS) in women and to identify foci for preventive nutrition interventions.

RESEARCH METHODS AND PROCEDURES

Dietary patterns, nutrient intake, cardiovascular disease (CVD), and MetS risk factors were characterized in 1615 Framingham Offspring-Spouse Study (FOS) women. Dietary pattern subgroups were compared for MetS prevalence and CVD risk factor status using logistic regression and analysis of covariance. Analyses were performed overall in women and stratified on obesity status; multivariate models controlled for age, apolipoprotein E (APOE) genotypes, and CVD risk factors.

RESULTS

Food and nutrient profiles and overall nutritional risk of five non-overlapping habitual dietary patterns of women were identified including Heart Healthier, Lighter Eating, Wine and Moderate Eating, Higher Fat, and Empty Calories. Rates of hypertension and low high-density lipoprotein levels were high in non-obese women, but individual MetS risk factor levels were substantially increased in obese women. Overall MetS risk varied by dietary pattern and obesity status, independently of APOE and CVD risk factors. Compared with obese or non-obese women and women overall with other dietary patterns, MetS was highest in those with the Empty Calorie pattern (contrast p value: p<0.05).

DISCUSSION

This research shows the independent relationship between habitual dietary patterns and MetS risk in FOS women and the influence of obesity status. High overall MetS risk and the varying prevalence of individual MetS risk factors in female subgroups emphasize the importance of preventive nutrition interventions and suggest potential benefits of targeted behavior change in both obese and non-obese women by dietary pattern.

Dietary Patterns and the Risk of Colorectal Cancer

Diet and lifestyle play a significant role in the development of colorectal cancer, but the full complexity of the association is not yet understood. Dietary pattern analysis is an important new technique that may help to elucidate the relationship. This review examines the most common techniques for extrapolating dietary patterns and reviews dietary pattern/colorectal cancer studies published between September 2011 and August 2012. The studies reviewed are consistent with prior research but include a more diverse international population. Results from investigations using a priori dietary patterns (i.e., diet quality scores) and a posteriori methods, which identify existing eating patterns (i.e., principal component analysis), continue to support the benefits of a plant-based diet with some dairy as a means to lower the risk of colorectal cancer, whereas a diet high in meats, refined grains, and added sugar appears to increase risk. The association between colorectal cancer and alcohol remains unclear.

Dietary patterns of women are associated with incident abdominal obesity but not metabolic syndrome

Data on the relationship between empirical dietary patterns and metabolic syndrome (MetS) and its components in prospective study designs are limited. In addition, demographic and lifestyle determinants of MetS may modify the association between dietary patterns and the syndrome. We prospectively examined the relationship between empirically derived patterns and MetS and MetS components among 1146 women in the Framingham Offspring/Spouse cohort. They were aged 25-77 y with BMI ≥18.5 kg/m(2) and free of cardiovascular disease, diabetes, cancer, and MetS at baseline, and followed for a mean of 7 y. Five dietary patterns, Heart Healthier, Lighter Eating, Wine and Moderate Eating, Higher Fat, and Empty Calorie, were previously identified using cluster analysis from food intake collected using a FFQ. After adjusting for potential confounders, we observed lower odds for abdominal obesity for Higher Fat [OR = 0.48 (95% CI: 0.25, 0.91)] and Wine and Moderate Eating clusters [OR = 0.28 (95% CI: 0.11, 0.72)] compared with the Empty Calorie cluster. Additional adjustment for BMI somewhat attenuated these OR [Higher Fat OR = 0.52 (95% CI: 0.27, 1.00); Wine and Moderate Eating OR = 0.34 (95% CI: 0.13, 0.89)]. None of the clusters was associated with MetS or other MetS components. Baseline smoking status and age did not modify the relation between dietary patterns and MetS. The Higher Fat and Wine and Moderate Eating patterns showed an inverse association with abdominal obesity; certain foods might be targeted in these habitual patterns to achieve optimal dietary patterns for MetS prevention.

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.

Stability of the Framingham Nutritional Risk Score and its component nutrients over 8 years: the Framingham Nutrition Studies

BACKGROUND/OBJECTIVES

Diet quality indices are increasingly used in nutrition epidemiology as dietary exposures in relation to health outcomes. However, literature on the long-term stability of these indices is limited. We aimed to assess the stability of the validated Framingham Nutritional Risk Score (FNRS) and its component nutrients over 8 years, as well as the validity of the follow-up FNRS.

SUBJECTS/METHODS

Framingham Offspring/Spouse Study women and men (n=1734) aged 22-76 years were evaluated over 8 years. Individuals' nutrient intake and nutritional risk scores were assessed using 3-day dietary records administered at baseline (1984-1988) and at follow-up (1992-1996). Agreement between baseline and follow-up FNRS and nutrient intakes was evaluated by Bland-Altman method; stability was assessed using intra-class correlation (ICC) and weighted Kappa statistics. The effect of diet quality (as assessed by the FNRS) on cardiometabolic risk factors was evaluated using analysis of covariance.

RESULTS

Modest changes from baseline (15%) were observed in nutrient intake. The stability coefficients for the FNRS (ICC: women, 0.49; men, 0.46; P<0.0001) and many nutrients (ICC 0.3) were moderate. Over half of the women and men (58%) remained in the same or contiguous baseline and follow-up quartile of the FNRS and few (3-4%) shifted >1 quartile. The FNRS was directly associated with body mass index in women (P<0.01) and high-density lipoprotein cholesterol among both women (P<0.001) and men (P<0.01).

CONCLUSIONS

The FNRS and its constituent nutrients remained relatively stable over 8 years of follow-up. The stability of diet quality has implications for prospective epidemiological investigations.

Dietary patterns are associated with disease risk among participants in the Women's Health Initiative Observational Study

Coronary heart disease (CHD) is the leading cause of death in women. A nested case-control study tested whether dietary patterns predicted CHD events among 1224 participants in the Women's Health Initiative-Observational Study (WHI-OS) with centrally confirmed CHD, fatal or nonfatal myocardial infarct compared to 1224 WHI-OS controls matched for age, enrollment date, race/ethnicity, and absence of CHD at baseline or follow-up. The first six principal components explained >75% of variation in dietary intakes and K-mean analysis based on these six components produced three clusters. Diet cluster 1 was rich in carbohydrate, vegetable protein, fiber, dietary vitamin K, folate, carotenoids, α-linolenic acid [18:3(n-3)], linoleic acid [18:2(n-6)], and supplemental calcium and vitamin D. Diet cluster 2 was rich in total and animal protein, arachidonic acid [20:4(n-6)], DHA [22:6(n-3)], vitamin D, and calcium. Diet cluster 3 was rich in energy, total fat, and trans fatty acids (all P < 0.01). Conditional logistic regression analysis demonstrated diet cluster 1 was associated with lower CHD risk than diet cluster 2 (reference group) adjusted for smoking, education, and physical activity [OR = 0.79 (95% CI = 0.64, 0.99); P = 0.038]. This difference was not significant after adjustment for BMI and systolic blood pressure. Diet cluster 3 was associated with higher CHD risk than diet cluster 2 [OR = 1.28 (95% CI = 1.04, 1.57); P = 0.019], but this difference did not remain significant after adjustment for smoking, education, and physical activity. Within this WHI-OS cohort, distinct dietary patterns may be associated with subsequent CHD outcomes.

Dietary patterns and bone mineral status in young adults: the Northern Ireland Young Hearts Project

Studies of individual nutrients or foods have revealed much about dietary influences on bone. Multiple food or nutrient approaches, such as dietary pattern analysis, could offer further insight but research is limited and largely confined to older adults. We examined the relationship between dietary patterns, obtained by a posteriori and a priori methods, and bone mineral status (BMS; collective term for bone mineral content (BMC) and bone mineral density (BMD)) in young adults (20-25 years; n 489). Diet was assessed by 7 d diet history and BMD and BMC were determined at the lumbar spine and femoral neck (FN). A posteriori dietary patterns were derived using principal component analysis (PCA) and three a priori dietary quality scores were applied (dietary diversity score (DDS), nutritional risk score and Mediterranean diet score). For the PCA-derived dietary patterns, women in the top compared to the bottom fifth of the 'Nuts and Meat' pattern had greater FN BMD by 0·074 g/cm(2) (P = 0·049) and FN BMC by 0·40 g (P = 0·034) after adjustment for confounders. Similarly, men in the top compared to the bottom fifth of the 'Refined' pattern had lower FN BMC by 0·41 g (P = 0·049). For the a priori DDS, women in the top compared to the bottom third had lower FN BMD by 0·05 g/cm(2) after adjustments (P = 0·052), but no other relationships with BMS were identified. In conclusion, adherence to a 'Nuts and Meat' dietary pattern may be associated with greater BMS in young women and a 'Refined' dietary pattern may be detrimental for bone health in young men.

Food pattern analysis over time: unhealthful eating trajectories predict obesity

BACKGROUND

Analysis of dietary patterns is prominent in nutrition literatures, yet few studies have taken advantage of multiple repeated measurements to understand the nature of individual-level changes over time in food choice, or the relation between these changes and body mass index (BMI).

OBJECTIVE

To investigate changes in eating patterns at the individual level across three exam periods, and to prospectively examine the relation of eating trajectories to BMI at the cohort level.

DESIGN

The study included 3418 participants at baseline. Clinically measured BMI and dietary intake were assessed during three exam periods between 1991 and 2001 using a validated food frequency questionnaire. An individual's eating trajectory across exam periods was analyzed using sequence analysis, and then used to estimate outcomes of continuous BMI and categorical obesity status. Ordinary least squares regression models with robust standard errors were adjusted for socio-economic and demographic confounders, baseline BMI and baseline eating.

RESULTS

A total of 66.2% (n=1614) of participants change their diet pattern during the study period, 33.8% (n=823) remain stable. After accounting for potential confounders, an unhealthful trajectory is significantly associated with a 0.42 kg m(-2) increase in BMI (confidence interval (CI): 0.1, 0.7). Those with an unhealthful trajectory are 1.79 times more likely to be overweight (relative risk ratio, 95% CI: 1.1, 2.8) and 2.4 times more likely to be obese (relative risk ratio, 95% CI: 1.3, 4.4). Moreover, a number of specific diet transitions between exams are predictive of weight gain or loss.

CONCLUSION

Contextualizing an individual's current eating behaviors with an eye towards diet history may be an important boon in the reduction of obesity. Although it may not be realistic for many people to shift from the least to most healthful diet, results from this study suggest that consistent movement in an overall healthier direction is associated with less weight gain.

Sociodemographic and lifestyle characteristics in relation to dietary patterns among young Brazilian adults

OBJECTIVE

To identify dietary patterns among young adults and the relationships with socio-economic, demographic and lifestyle characteristics.

DESIGN

Population-based, cross-sectional analysis of a cohort study. Food intake was assessed by a frequency questionnaire, and dietary patterns were identified using principal components analysis.

SETTING

Southern Brazil.

SUBJECTS

A total of 4202 men and women aged 23 years, who participated in the 1982 Pelotas Birth Cohort Study.

RESULTS

Five dietary patterns were identified: common Brazilian, processed food, vegetable/fruit, dairy/dessert and tubers/pasta. Subjects who had low own or maternal educational levels, low social position or who were always poor throughout life had high adherence to the common Brazilian dietary pattern. In contrast, the processed food pattern was more likely to be followed by those belonging to middle and high social position and who were never poor. Men and smokers showed high adherence to the processed food and common Brazilian dietary patterns. Vegetable/fruit pattern was more likely to be followed by women and subjects engaged in physical activity. Women also showed high adherence to the dairy/dessert pattern.

CONCLUSIONS

Our study among young Brazilian adults has identified distinct dietary patterns that are clearly influenced by socio-economic and lifestyle characteristics, which have important policy implications in a country with marked social and economic inequalities.

Diet quality, physical activity, smoking status, and weight fluctuation are associated with weight change in women and men

The effect of diet quality on weight change, relative to other body weight determinants, is insufficiently understood. Furthermore, research on long-term weight change in U.S. adults is limited. We evaluated prospectively patterns and predictors of weight change in Framingham Offspring/Spouse (FOS) women and men (n = 1515) aged > or =30 y with BMI > or = 18.5 kg/m2 and without cardiovascular disease, diabetes, and cancer at baseline over a 16-y period. Diet quality was assessed using the validated Framingham Nutritional Risk Score. In women, older age (P < 0.0001) and physical activity (P < 0.05) were associated with lower weight gain. Diet quality interacted with former smoking status (P-interaction = 0.02); former smokers with lower diet quality gained an additional 5.2 kg compared with those with higher diet quality (multivariable-adjusted P-trend = 0.06). Among men, older age (P < 0.0001) and current smoking (P < 0.01) were associated with lower weight gain, and weight fluctuation (P < 0.01) and former smoking status (P < 0.0001) were associated with greater weight gain. Age was the strongest predictor of weight change in both women (partial R(2) = 11%) and men (partial R(2) = 8.6%). Normal- and overweight women gained more than obese women (P < 0.05) and younger adults gained more weight than older adults (P < 0.0001). Patterns and predictors of weight change differ by sex. Age in both sexes and physical activity among women as well as weight fluctuation and smoking status in men were stronger predictors of weight change than diet quality among FOS adults. Women who stopped smoking over follow-up and had poor diet quality gained the most weight. Preventive interventions need to be sex-specific and consider lifestyle factors.

Analysis of dietary patterns in epidemiological researchThis paper is one of a selection of papers published in the CSCN–CSNS 2009 Conference, entitled Are dietary patterns the best way to make nutrition recommendations for chronic disease prevention?

Dietary patterns have been used to summarize diet consumption and to evaluate how diet is associated with diseases in epidemiological research. However, there are many issues surrounding both the use and interpretation of dietary patterns. These issues include how to collect, summarize, and create dietary patterns, as well as how to interpret the results. Because labels are given arbitrarily to dietary patterns to help characterize the pattern in a meaningful way, it is often not clear from the literature as to the consistency of results among studies. Additionally, the utilization of dietary patterns as a tool for public health messages is a topic that is unresolved. These issues are discussed in this paper.

Cross-sectional association of dietary patterns with insulin-resistant phenotypes among adults without diabetes in the Framingham Offspring Study

Cluster analysis is a valuable tool for exploring the health consequences of consuming different dietary patterns. We used this approach to examine the cross-sectional relationship between dietary patterns and insulin-resistant phenotypes, including waist circumference, BMI, fasting insulin, 2 h post-challenge insulin, insulin sensitivity index (ISI0,120), HDL-cholesterol, TAG and blood pressure, using data from the fifth examination cycle of the Framingham Offspring Study. Among 2875 participants without diabetes, we identified four dietary patterns based on the predominant sources of energy: 'Fruits, Reduced Fat Dairy and Whole Grains', 'Refined Grains and Sweets', 'Beer' and 'Soda'. After adjusting for multiple comparisons and potential confounders, compared with the 'Fruits, Reduced Fat Dairy and Whole Grains' pattern, the 'Refined Grains and Sweets' pattern had significantly higher mean waist circumference (92.4 v. 90.5 cm; P = 0.008) and BMI (27.3 v. 26.6 kg/m2; P = 0.02); the 'Soda' pattern had significantly higher mean fasting insulin concentration (31.3 v. 28.0 microU/ml; P < or = 0.001); the 'Beer' pattern had significantly higher mean HDL-cholesterol concentration (1.46 v. 1.31 mmol/l; P < 0.001). No associations were observed between dietary patterns and ISI0,120, TAG, and systolic or diastolic blood pressure. Our findings suggest that consumption of a diet rich in fruits, vegetables, whole grains and reduced-fat dairy protects against insulin-resistant phenotypes and displacing these healthy choices with refined grains, high-fat dairy, sweet baked foods, candy and sugar-sweetened soda may promote insulin-resistant phenotypes.

Validity of dietary patterns to assess nutrient intake adequacy

The purpose of the present study was to conduct a systematic review of the literature on the value of the methods used to assess dietary patterns for measuring nutrient intake adequacy in the population. Systematic review on Pubmed database up to April 2008. The search included specific key words and MeSH terms. No language limit was set. Only studies that compared food patterns with nutrient intake adequacy or nutrient biomarkers were included in the analysis. The search resulted in 1504 articles. The inclusion and exclusion criteria limited the selection to thirty articles. Nineteen studies evaluated the usefulness of the dietary patterns, eithera prioridefined (thirteen studies), or defined by factor analysis (four studies) or by cluster analysis (two studies), but only nine of them tested their validity (foura prioridefined and foura posterioridefined). Diet indices showed moderate to good validity results for measuring the adequacy of intakes for α-carotene, β-carotene, vitamin C, vitamin B6, Ca, folic acid, Fe and Mg. The factor analysis approach showed moderate to good validity correlations with the adequacy of intake of α-carotene, β-carotene, lutein, lycopene, vitamin C, vitamin B6and folic acid. Vitamin B12and vitamin E are the micronutrients with less probability of being adequately assessed with dietary patternsa prioriora posterioridefined. Diet indices are tools with fair to moderate validity to assess micronutrient intake adequacy.

Mothers of young children cluster into 4 groups based on psychographic food decision influencers

This study explored how mothers grouped into clusters according to multiple psychographic food decision influencers and how the clusters differed in nutrient intake and nutrient content of their household food supply. Mothers (n = 201) completed a survey assessing basic demographic characteristics, food shopping and meal preparation activities, self and spouse employment, exposure to formal food or nutrition education, education level and occupation, weight status, nutrition and food preparation knowledge and skill, family member health and nutrition status, food decision influencer constructs, and dietary intake. In addition, an in-home inventory of 100 participants' household food supplies was conducted. Four distinct clusters presented when 26 psychographic food choice influencers were evaluated. These clusters appear to be valid and robust classifications of mothers in that they discriminated well on the psychographic variables used to construct the clusters as well as numerous other variables not used in the cluster analysis. In addition, the clusters appear to transcend demographic variables that often segment audiences (eg, race, mother's age, socioeconomic status), thereby adding a new dimension to the way in which this audience can be characterized. Furthermore, psychographically defined clusters predicted dietary quality. This study demonstrates that mothers are not a homogenous group and need to have their unique characteristics taken into consideration when designing strategies to promote health. These results can help health practitioners better understand factors affecting food decisions and tailor interventions to better meet the needs of mothers.

Dietary glycemic index, glycemic load, and risk of cancer: a prospective cohort study

Previous studies have provided limited evidence for a harmful effect of high glycemic index and dietary glycemic load on cancer. The authors analyzed associations among glycemic index, glycemic load, and risk of cancer in women and men in the National Institutes of Health-AARP Diet and Health Study. Published glycemic index values were assigned to 225 foods/food groups. Glycemic load was calculated by multiplying the glycemic index, carbohydrate content, and intake frequency of individual foods reported on a food frequency questionnaire. From 1995 through 2003, the authors identified 15,215 and 33,203 cancer cases in women and men, respectively. Cox proportional hazards models were used to estimate multivariate relative risks and 95% confidence intervals. For women and men, respectively, the relative risks for total cancer for high versus low glycemic index were 1.03 (P(trend)=0.217) and 1.04 (P(trend)=0.012) and, for glycemic load, were 0.90 (P(trend)=0.024) and 0.93 (P(trend)=0.01). Associations with total cancer held only among the overweight for glycemic index and among those of healthy weight for glycemic load. These findings suggest that glycemic index and glycemic load are not strong predictors of cancer incidence. The direction and small magnitude of associations might be explained by the manner in which high glycemic index and glycemic load track with overall diet and lifestyle patterns.

Obesogenic clusters: multidimensional adolescent obesity-related behaviors in the U.S

BACKGROUND

Diet, physical activity, and psychosocial factors are independent and potentially interactive obesity determinants, but few studies have explored complex behavior patterns.

PURPOSE

The purpose of this study is to examine obesity-related behavior patterning and identify high-risk adolescent groups.

METHODS

Cluster analysis identified groups with shared behavior patterns in the National Longitudinal Study of Adolescent Health (1995 and 1996, ages 11-21; N = 9,251). Descriptive and multivariate regression analyses compared sociodemographics and prevalent and incident obesity across clusters.

RESULTS

Seven and six clusters in males and females, respectively, represented behavior patterns such as School Clubs & Sports, Sedentary Behaviors, Dieters, and Junk Food & Low Activity. Sociodemographics varied across clusters. Compared to School Clubs & Sports clusters, adjusted odds of prevalent and incident obesity were higher for most clusters in females but not males.

CONCLUSIONS

Cluster analysis identified several obesogenic behavior patterns, highlighting areas for future research and potential avenues for interventions that target broad lifestyle factors.

Dietary patterns and health and nutrition outcomes in men living with HIV infection

BACKGROUND

Nutritional status is an important determinant of HIV outcomes.

OBJECTIVE

We assessed the association between dietary patterns identified by cluster analysis and change in body mass index (BMI; in kg/m(2)), CD4 count, and viral load (VL).

DESIGN

HIV-positive adult male subjects (n = 348) with a BMI >or= 20.5 were evaluated by biochemical, body composition, and dietary data. Cluster analysis was performed on 41 designated food groups derived from 3-d food records. Dietary clusters were compared for sociodemographic, nutrient intake, and clinical outcomes. Multivariate linear regression assessed associations between dietary clusters and change in BMI, CD4 count, and VL.

RESULTS

We observed 3 dietary patterns: juice and soda; fast food and fruit drinks; and fruit, vegetable, and low-fat dairy. Subjects in the fast food and fruit drinks pattern had the lowest fiber intake, highest VL, and lowest CD4 count and had a lower income than did subjects in the other 2 clusters. Subjects in the fruit, vegetable, and low-fat dairy diet pattern had higher intakes of protein, fiber, and micronutrients and the highest BMI and CD4 count. Subjects in the juice and soda pattern had higher energy intakes and lowest BMI. On average, the fast food and fruit drinks cluster and fruit, vegetable, and low-fat dairy cluster gained 0.33 (P = 0.06) and 0.42 (P = 0.02), respectively, more in BMI than the juice and soda cluster across the study interval in a multivariate model.

CONCLUSIONS

In a cohort of HIV-positive men, we identified 3 distinct dietary patterns; each pattern was associated with specific nutrition, demographic, and HIV-related variables.

Performance of a method for identifying the unique dietary patterns of adult women and men: the Framingham nutrition studies

BACKGROUND

Identification of population dietary patterns has been recommended by experts as a key to developing innovative and targeted nutrition interventions and achieving long-term dietary behavior changes for health promotion and chronic disease risk reduction. Essential in this task is the evaluation of methods to accurately identify these unique dietary patterns.

OBJECTIVE

To evaluate the validity and test the performance of a method for classifying adult men and women into one of five a priori dietary patterns.

DESIGN

The first examination of Framingham Nutrition Studies took place between 1984 and 1987 and included 1,828 women and 1,666 men who completed the Framingham semi-quantitative food frequency questionnaire. Five unique dietary patterns for each sex were identified. Here we used Fisher's discriminant functions to create classification algorithms for identifying the dietary patterns of new individuals. Its validity and performance was evaluated using a variety of statistical tools.

RESULTS

The new Framingham Dietary Pattern algorithm classified about 80% of women or men correctly and kappa statistics exceeded 0.70. The cluster-specific sensitivities ranged from 0.70 to 1.00 and specificities were all >0.88. The pooled conditional c statistics were 0.95 and 0.96 for women and men, respectively. Overall, we can be confident that our methodology offers a valid identification of male and female dietary patterns when applied in practice.

CONCLUSIONS

The Framingham Dietary Pattern technique is a valid and reliable method for identifying the unique dietary behavior of adults. Our approach can also be used to guide the development and evaluation of other composite dietary quality indices.

Under-reporting of energy intake is more prevalent in a healthy dietary pattern cluster

The aim of the present study was to determine whether under-reporting rates vary between dietary pattern clusters. Subjects were sixty-five Brazilian women. During 3 weeks, anthropometric data were collected, total energy expenditure (TEE) was determined by the doubly labelled water method and diet was measured. Energy intake (EI) and the daily frequency of consumption per 1000 kJ of twenty-two food groups were obtained from a FFQ. These frequencies were entered into a cluster analysis procedure in order to obtain dietary patterns. Under-reporters were defined as those who did not lose more than 1 kg of body weight during the study and presented EI:TEE less than 0.82. Three dietary pattern clusters were identified and named according to their most recurrent food groups: sweet foods (SW), starchy foods (ST) and healthy (H). Subjects from the healthy cluster had the lowest mean EI:TEE (SW = 0.86, ST = 0.71 and H = 0.58; P = 0.003) and EI - TEE (SW = - 0.49 MJ, ST = - 3.20 MJ and H = - 5.08 MJ; P = 0.008). The proportion of under-reporters was 45.2 (95 % CI 35.5, 55.0) % in the SW cluster; 58.3 (95 % CI 48.6, 68.0) % in the ST cluster and 70.0 (95 % CI 61.0, 79) % in the H cluster (P = 0.34). Thus, in Brazilian women, under-reporting of EI is not uniformly distributed among dietary pattern clusters and tends to be more severe among subjects from the healthy cluster. This cluster is more consistent with both dietary guidelines and with what lay individuals usually consider 'healthy eating'.

Maternal dietary omega fatty acid intake and auditory brainstem-evoked potentials in Mexican infants born at term: cluster analysis

OBJECTIVE

To identify biological and socioeconomic factors associated with the neurological development of Mexican infants born at term, as measured by brainstem auditory-evoked potentials (BAEPs).

SUBJECTS AND METHODS

We conducted a cohort study among 76 women with low risk pregnancies recruited in their third trimester of pregnancy and followed their infants until 12 months of age. BAEP tests were conducted on the infants before 3 months of age during physiologic sleep, using 100 msec bipolar clicks. Maternal dietary intake was evaluated by food frequency questionnaire. Two BAEP groups (short latency, long latency) were identified by cluster analysis. The association between BAEP group and maternal PUFAs was estimated using logistic regression models adjusted for socioeconomic and biological factors.

RESULTS

Short latency BAEPs were associated with a maternal diet rich in arachidonic acid (OR=3.63, 95% CI 1.23-10.67) after adjusting for age (in days) sex, head circumference and gestational age but was not significantly associated to a maternal diet rich in docosahexaenoic acid (DHA).

CONCLUSIONS

Our results suggest the importance of arachidonic acid intake during pregnancy for short latency BAEPs and adequate fetal myelination.