Methods for the dietary assessment of adult kidney stone formers: a scoping review

BACKGROUND

Kidney stones are a frequent and potentially severe condition, affecting 5-10% of the European population. Causes are multifactorial, diet in particular plays a major role in the formation and management of kidney stones. The aim of this scoping review is to assess the methods used to study the diet of adult kidney stone formers.

METHODS

We conducted a systematic search in Medline Ovid SP, Embase, Cinahl, Cochrane (CENTRAL), Web of Sciences databases on June 10th, 2020. Self-report methods (such as food frequency questionnaires or 24-h dietary recalls), objective nutritional biomarkers and controlled diets were considered. We analyzed the selected publications based on the origin of participants, study design and dietary assessment methods used.

RESULTS

We screened 871 publications and included 162 of them. Most studies included participants from North America and Europe and were observational. Short and cost-effective tools such as food frequency questionnaires and other questionnaires were the most frequently used. Moreover, food diary was a frequently selected method to study the diet of kidney stone formers. New technologies (e.g. online questionnaires, phone applications, connected tools) were rarely used.

CONCLUSION

Accurate reporting of the methods used in nutritional studies is of key importance to interpret results and build evidence. Assessing long-term dietary intake is still a challenge for nutritional epidemiology. A combination of self-report methods with objective dietary biomarkers and new technologies probably represents the best way forward.

Bayesian Copula Density Deconvolution for Zero-Inflated Data in Nutritional Epidemiology

Estimating the marginal and joint densities of the long-term average intakes of different dietary components is an important problem in nutritional epidemiology. Since these variables cannot be directly measured, data are usually collected in the form of 24-hour recalls of the intakes, which show marked patterns of conditional heteroscedasticity. Significantly compounding the challenges, the recalls for episodically consumed dietary components also include exact zeros. The problem of estimating the density of the latent long-time intakes from their observed measurement error contaminated proxies is then a problem of deconvolution of densities with zero-inflated data. We propose a Bayesian semiparametric solution to the problem, building on a novel hierarchical latent variable framework that translates the problem to one involving continuous surrogates only. Crucial to accommodating important aspects of the problem, we then design a copula based approach to model the involved joint distributions, adopting different modeling strategies for the marginals of the different dietary components. We design efficient Markov chain Monte Carlo algorithms for posterior inference and illustrate the efficacy of the proposed method through simulation experiments. Applied to our motivating nutritional epidemiology problems, compared to other approaches, our method provides more realistic estimates of the consumption patterns of episodically consumed dietary components.

Dietary inflammatory index scores are associated with atherogenic risk in Brazilian schoolchildren

OBJECTIVE

To investigate the association between the Children's Dietary Inflammatory Index (C-DIITM) scores and atherogenic risk in Brazilian schoolchildren.

DESIGN

A cross-sectional representative study. Three 24-h dietary recalls were performed to evaluate food consumption and to calculate C-DII scores. Blood samples were collected for the lipid profile analysis (serum total cholesterol (TC), HDL-cholesterol, LDL-cholesterol, VLDL-cholesterol and triglycerides (TAG)) and to determine atherogenic indexes (Castelli risk indexes I and II, lipoprotein combined index (LCI), and atherogenic index of plasma and atherogenic coefficient (AC)). A semi-structured questionnaire was used to obtain sociodemographic characteristics and screen time. Body fat was assessed by dual-energy X-ray absorptiometry. We compared the distributions of outcomes by C-DII categories using multivariable linear regression.

SETTING

Viçosa, Minas Gerais, Brazil.

PARTICIPANTS

Three hundred seventy-eight children between the ages of 8 and 9 years.

RESULTS

The mean C-DII score was 0·60 ± 0·94, and the prevalence of dyslipidaemia was 70 %. Children with hypercholesterolaemia and hypertriglyceridaemia had higher C-DII scores. The C-DII was directly associated with atherogenic risk. Every 1 sd of C-DII was associated with a 0·07 (0·01, 0·13), 1·94 (0·20, 3·67), 0·06 (0·002, 0·12) and 0·12 (0·02, 0·22) units higher TC:HDL cholesterol ratio, LCI, AC and accumulation of altered dyslipidaemia markers (high TC + high LDL-cholesterol + high TAG + low HDL-cholesterol), respectively.

CONCLUSIONS

Dietary inflammatory potential, as estimated by the C-DII, is directly associated with atherogenic risk in Brazilian schoolchildren. This results reinforce the importance of effective nutritional policies to promote healthy eating habits and improve children's lipid profiles.

Diet scores and prediction of general and abdominal obesity in the Melbourne collaborative cohort study

OBJECTIVE

To ascertain which of the Alternative Healthy Eating Index (AHEI) 2010, Dietary Inflammatory Index (DII®) and Mediterranean Diet Score (MDS) best predicted BMI and waist-to-hip circumference ratio (WHR).

DESIGN

Body size was measured at baseline (1990-1994) and in 2003-2007. Diet was assessed at baseline using a FFQ, along with age, sex, socio-economic status, smoking, alcohol drinking, physical activity and country of birth. Regression coefficients and 95 % CI for the association of baseline dietary scores with follow-up BMI and WHR were generated using multivariable linear regression, adjusting for baseline body size, confounders and energy intake.

SETTING

Population-based cohort in Melbourne, Australia.

PARTICIPANTS

Included were data from 11 030 men and 16 774 women aged 40-69 years at baseline.

RESULTS

Median (IQR) follow-up was 11·6 (10·7-12·8) years. BMI and WHR at follow-up were associated with baseline DII® (Q5 v. Q1 (BMI 0·41, 95 % CI 0·21, 0·61) and WHR 0·009, 95 % CI 0·006, 0·013)) and AHEI (Q5 v. Q1 (BMI -0·51, 95 % CI -0·68, -0·35) and WHR -0·011, 95 % CI -0·013, -0·008)). WHR, but not BMI, at follow-up was associated with baseline MDS (Group 3 most Mediterranean v. G1 (BMI -0·05, 95 % CI -0·23, 0·13) and WHR -0·004, 95 % CI -0·007, -0·001)). Based on Akaike's Information Criterion and Bayesian Information Criterion statistics, AHEI was a stronger predictor of body size than the other diet scores.

CONCLUSIONS

Poor quality or pro-inflammatory diets predicted overall and central obesity. The AHEI may provide the best way to assess the obesogenic potential of diet.

Prevalence and predictors of vitamin D deficiency in a nationally representative sample of Australian Aboriginal and Torres Strait Islander adults

Vitamin D deficiency (serum 25-hydroxyvitamin D (25(OH)D) concentration <50 nmol/l) is recognised as a public health problem globally. The present study details the prevalence and predictors of vitamin D deficiency in a nationally representative sample (n 3250) of Australian Aboriginal and Torres Strait Islander adults aged ≥18 years. We used data from the 2012-2013 Australian Aboriginal and Torres Strait Islander Health Survey (AATSIHS). Serum 25(OH)D concentrations were measured by liquid chromatography-tandem MS. Survey-weighted logistic regression models were used to determine the independent predictors of vitamin D deficiency. Approximately 27 % of adult AATSIHS participants were vitamin D deficient. Vitamin D deficiency was more prevalent in remote areas (39 %) than in non-remote areas (23 %). Independent predictors of vitamin D deficiency included assessment during winter (men, adjusted OR (aOR) 5·7; 95 % CI 2·2, 14·6; women, aOR 2·2; 95 % CI 1·3, 3·8) and spring (men, aOR 3·3; 95 % CI 1·4, 7·5; women, aOR 2·6; 95 % CI 1·5, 4·5) compared with summer, and obesity (men, aOR 2·6; 95 % CI 1·2, 5·4; women, aOR 4·3; 95 % CI 2·8, 6·8) compared with healthy weight. Statistically significant associations were evident for current smokers (men only, aOR 2·0; 95 % CI 1·2, 3·4), remote-dwelling women (aOR 2·0; 95 % CI 1·4, 2·9) and university-educated women (aOR 2·4; 95 % CI 1·2, 4·8). Given the high prevalence of vitamin D deficiency in this population, strategies to maintain adequate vitamin D status through safe sun exposure and dietary approaches are needed.

Moment estimation method of parameters in additive measurement error model

BACKGROUND

In nutritional epidemiology, covariates in some studies such as the EPIC are prone to measurement error. Estimation of unknown parameters in most measurement error models for food frequency questionnaire (FFQ) and nutrient biomarkers requires replicated measurements. But, the EPIC-InterAct Study did not collect replicated measurements for FFQ or 24-hour dietary recalls (24HR). The method of correcting measurement error in this case is worth studying.

METHODS

A moment method is applied to estimate unknown parameters of the proposed error model with correlated errors between biased measurements of FFQ and 24HR. Then, correction factor and reliability ratio of each error-prone nutrient can be obtained correspondingly. Afterwards, regression calibration (RC) under a Cox model is used to correct measurement error of nutrients of interest in the EPIC-InterAct data.

RESULTS

Compared to the naive estimation, estimation results for dietary intakes could be very different when we take measurement error into consideration. Using RC as the correction method, hazard ratios (HR) of vegetable plus fruit, fat and energy for males become 1.01 (95% CI 0.75-1.35), 1.30 (95% CI 1.12-1.51) and 1.16 (95% CI 1.04-1.28), respectively, and HR of energy for females becomes 0.99 (95% CI 0.91-1.08). These HRs are greatly different from those by naive estimation.

CONCLUSIONS

Although there is no repeated measurement for FFQ and 24HR, we can still estimate all unknown parameters in our proposed error model under four assumptions and then correct measurement error in nutrients of interest in EPIC-InterAct Study by RC for avoiding some misleading results from naive estimation.

Knowledge, attitude and behaviour of university students regarding salt and iodine: a multicentre cross-sectional study in six countries in Europe and Asia

Background

Strategies to reduce salt intake are encouraged to be implemented in parallel with those that aim to ensure iodine adequacy at the population level. The aim of the present study was to assess and compare knowledge, attitudes and behaviours related to salt and iodine among students in Europe and Asia.

Methods

A multicentre cross-sectional study was conducted with 2459 university students in total (42.7% males, median age 21 years) from four countries in Europe and two countries in Asia. Data were collected with the use of a self-administered questionnaire, and univariate and multivariate statistical analyses were performed to explore any association between variables.

Results

Only 6.5% of all participants knew the correct salt recommendations. Nearly a quarter of them (24.4%) found salt recommendations confusing and/or contradictory. There were significant differences between European and Asian participants, with those from Europe being better informed about salt recommendations, but significantly less knowledgeable about iodine. The reported frequency of use of salt and salt-containing sauces either at the table or for cooking, as well as knowledge about ways to reduce salt intake among those who indicated to make conscious efforts to do so, differed significantly between countries. Significant differences between countries were also observed with respect to the type of salt used, with about one third of all participants (34%) not being aware of the kind of salt they used.

Conclusion

The results of this survey highlight serious salt- and iodine-related knowledge gaps among university students in Europe and Asia. Raising awareness and conducting information campaigns is needed to promote changes in behaviour that would result in a reduction of salt intake and conscious use of iodised salt at the individual level.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13690-021-00593-5.

Frequency of consumption of balanced meals, bodyweight gain and incident risk of glucose intolerance in Japanese men and women: A cohort study

AIMS/INTRODUCTION

This cohort study assessed the risk for bodyweight gain and development of glucose intolerance based on the frequency of consumption of balanced meals including grain, fish or meat and vegetables.

MATERIALS AND METHODS

The participants (8,573 men, 3,327 women) were employees of a company in Japan. A self-administered questionnaire was used to evaluate the frequency of balanced meal consumption. Bodyweight changes and the incidence of glucose intolerance (glycated hemoglobin >6.0%) during the 3-year follow-up period were determined through annual health examinations.

RESULTS

The mean bodyweight change over a period of 3 years was 0.78 kg for men and 0.84 kg for women. A lower frequency of balanced meals was associated with a higher bodyweight gain for men (P for trend = 0.004), but not for women. During the study, 464 men and 115 women developed glucose intolerance. Overall, the frequency of balanced meals was not associated with the risk of glucose intolerance in either sex. However, the interaction between the frequency of balanced meals and degree of obesity had a significant effect on the incidence of glucose intolerance in men (P = 0.005), with less frequent consumption of balanced meals being associated with a higher risk for glucose intolerance among men with a BMI ≥25.0 kg/m2 (P for trend = 0.007).

CONCLUSIONS

A higher frequency of balanced meals, including grain, fish or meat and vegetable dishes - important components of healthy Japanese food - was associated with a lower risk of glucose intolerance in obese men, but not in non-obese men and women.

Breastfeeding and Childhood Dental Caries: Results from a Socially Diverse Birth Cohort Study

Previous studies showed that prolonged breastfeeding increases the risk of caries. However, the observed associations were mainly based on non-European populations, and important confounding and mediating factors like socioeconomic position (SEP) and diet were often neglected. The aim of this study was to investigate the role of breastfeeding and bottle-feeding practices on dental caries during childhood while accounting for SEP, ethnic background, and sugar intake. This study was part of the Generation R Study, a prospective multiethnic cohort study conducted in Rotterdam, The Netherlands. In total, 4,146 children were included in the analyses. Information about feeding practices was derived from delivery reports and questionnaires during infancy. Caries was measured via intraoral photographs at the age of 6 years and defined as decayed, missing, and filled teeth (dmft). Negative binomial hurdle regression analyses were used to study the associations between several infant feeding practices and childhood caries. The prevalence of dental caries at the age of 6 years was 27.9% (n = 1,158). Prolonged breastfeeding (for >12 months) was associated with dental caries (OR 1.35, 95% CI 1.04-1.74) and the number of teeth affected by dental caries (RR 1.27, 95% CI 1.03-1.56). Furthermore, nocturnal bottle-feeding was associated with dental caries (OR 1.52, 95% CI 1.20-1.93). All associations were independent of family SEP, ethnic background, and sugar intake. Results from this Dutch cohort study confirmed the previously observed associations between prolonged breastfeeding and nocturnal bottle-feeding and the increased risk of childhood dental caries, even after proper adjustments for indicators of SEP, ethnic background, and sugar intake. Future studies are encouraged to elaborate further on possible explanations for the observed relationships. Healthcare professionals should be aware and advise caregivers about the potential risk of prolonged breastfeeding on caries development by applying the current recommendations on breastfeeding, oral hygiene, and feeding frequency.

Correlates of a southern diet pattern in a national cohort study of blacks and whites: the REasons for Geographic And Racial Differences in Stroke (REGARDS) study

The Southern dietary pattern, derived within the REasons for Geographic And Racial Differences in Stroke (REGARDS) cohort, is characterised by high consumption of added fats, fried food, organ meats, processed meats and sugar-sweetened beverages and is associated with increased risk of several chronic diseases. The aim of the present study was to identify characteristics of individuals with high adherence to this dietary pattern. We analysed data from REGARDS, a national cohort of 30 239 black and white adults ≥45 years of age living in the USA. Dietary data were collected using the Block 98 FFQ. Multivariable linear regression was used to calculate standardised beta coefficients across all covariates for the entire sample and stratified by race and region. We included 16 781 participants with complete dietary data. Among these, 34·6 % were black, 45·6 % male, 55·2 % resided in stroke belt region and the average age was 65 years. Black race was the factor with the largest magnitude of association with the Southern dietary pattern (Δ = 0·76 sd, P < 0·0001). Large differences in Southern dietary pattern adherence were observed between black participants and white participants in the stroke belt and non-belt (stroke belt Δ = 0·75 sd, non-belt Δ = 0·77 sd). There was a high consumption of the Southern dietary pattern in the US black population, regardless of other factors, underlying our previous findings showing the substantial contribution of this dietary pattern to racial disparities in incident hypertension and stroke.

The dietary inflammatory index is associated with anti- and pro-inflammatory adipokines in Brazilian schoolchildren

PURPOSE

To investigate the relationship of Children's Dietary Inflammatory Index (C-DII™) scores with body fat distribution and serum adipokines in Brazilian schoolchildren.

METHODS

This population-based cross-sectional study enrolled 378 schoolchildren aged 8 and 9 years from Viçosa, Minas Gerais, Brazil. Food consumption was assessed using three 24-h dietary recalls from which C-DII scores were calculated. Serum adipokines [adiponectin, leptin, retinal-binding protein 4 (RBP4), and chemerin] were analyzed in blood samples. Sociodemographic characteristics and sedentary behavior were assessed using a semi-structured questionnaire. Total, truncal, android and gynoid body fat were evaluated by dual-energy X-ray absorptiometry (DXA). We compared the distributions of adiposity measures and serum adipokines by C-DII categories with linear regression, adjusting for potential confounders.

RESULTS

The mean sample C-DII was 0.59 ± 0.94 and ranged from - 2.16 to + 2.75. The C-DII was not associated with central and total body fat. However, the C-DII was modestly inversely associated with adiponectin and RBP4, and modestly directly associated with chemerin. These results remained significant after adjusting for body fat. Every 1 SD of C-DII was related, respectively, to a - 0.8 (- 1.5, - 0.03) and to a - 0.1 (- 0.2, - 0.05) units lower mean of adiponectin and RBP4, and to 7.2 (0.3, 14.1) units higher of chemerin.

CONCLUSION

Higher C-DII score was modestly inversely and directly associated with anti- and pro-inflammatory adipokines, respectively, in Brazilian children. The development of public health policies is needed to promote healthy eating habits during childhood to prevent the early onset of systemic inflammation and ill health effects later in life.

Alcohol consumption and risk of cardiovascular disease, cancer and mortality: a prospective cohort study

Background

Studies regarding whether light to moderate alcohol consumption is associated with a lower risk of cardiovascular diseases (CVD) have generated mixed results. Further, few studies have examined the potential impact of alcohol consumption on diverse disease outcomes simultaneously. We aimed to prospectively study the dose-response association between alcohol consumption and risk of CVD, cancer, and mortality.

Methods

This study included 83,732 adult Chinese participants, free of CVD and cancer at baseline. Participants were categorized into 6 groups based on self-report alcohol consumption: 0, 1–25, 26–150, 151–350, 351–750, and > 750 g alcohol/wk. Incident cases of CVD, cancers, and mortality were confirmed by medical records. Hazard ratios (HRs) for the composite risk of these three outcomes, and each individual outcome, were calculated using Cox proportional hazard model.

Results

During a median follow-up of 10.0 years, there were 6411 incident cases of CVD, 2947 cancers and 6646 deaths. We observed a J-shaped relation between alcohol intake and risk of CVD, cancer, and mortality, with the lowest risk at 25 g/wk., which is equivalent to ~ 2 servings/wk. Compared to consuming 1–25 g/wk., the adjusted HR for composite outcomes was 1.38 (95% confidence interval (CI):1.29–1.49) for non-drinker, 1.15 (95% CI: 1.04–1.27) for 26–150 g/wk., 1.22 (95% CI: 1.10–1.34) for 151–350 g/wk., 1.33 (95% CI: 1.21–1.46) for 351–750 g/wk., and 1.57 (95% CI: 1.30–1.90) for > 750 g/wk., after adjusting for age, sex, lifestyle, social economic status, and medication use.

Conclusions

Light alcohol consumption at ~ 25 g/wk was associated with lower risk of CVD, cancer, and mortality than none or higher consumption in Chinese adults.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12937-021-00671-y.

Association of self-reported moderate vegetable juice intake with small decline in kidney function in a five-year prospective study

OBJECTIVES

Although consumption of vegetable and 100% fruit juices are an acceptable alternative for vegetable and fruit intake, information about their actual effects on kidney function is sparse. The aim of this study was to determine the association between the consumption of vegetable and fruit juices and changes in kidney function in a Japanese population over a 5-y period.

METHODS

In this prospective study, we analyzed 2755 Japanese (742 men and 2013 women) individuals who participated in both the baseline and follow-up surveys in the Daiko study (a study within the Japan Multi-Institutional Collaborative Cohort study). Estimated glomerular filtration rate (eGFR) was calculated by age, sex, and serum creatinine level. For each beverage, we categorized all participants into four groups-rare (rarely consumed), low (≤2 cups/wk), moderate (3-4 cups/wk), or frequent (≥5 cups/wk) consumers of the beverage-based on a food frequency questionnaire.

RESULTS

The mean baseline and follow-up eGFR (SD) were 82.4 (14.6) and 72.2 (12.6), respectively. In fully adjusted regression analyses, moderate consumption of vegetable juice was associated a lower decline in eGFR compared with the rare consumption group (β = -1.30; P = 0.01). Moreover, stratified analyses revealed that this significant association remained in those who were young, female, non-obese, normotensive, smoked cigarettes, consumed alcohol, or exercised. However, no significant association was found in analyses for fruit juices.

CONCLUSIONS

This 5-y prospective study suggested an association between self-reported moderate consumption of vegetable juice and changes (possibly smaller decline) in kidney function in a relatively healthy Japanese population.

[Method of dietary nutritional status assessment and its application in cohort study of nutritional epidemiology]

Minimizing the burden on study subjects and assessing the general dietary nutritional status as accurately as possible are the basis of a nutritional epidemiological cohort study in the general population. While introducing the main dietary nutrition assessment methods, this paper manly describes the basic contents and principles for the development of food frequency questionnaire, and briefly illustrates the problems and solutions for the development of area specific food frequency questionnaires by taking the example of Tianjin Chronic Low-grade Systemic Inflammation and Health (TCLSIH) cohort study. Finally, discusses preliminarily the necessity and possibility of developing a national food frequency questionnaire.

High consumption of ultra-processed food may double the risk of subclinical coronary atherosclerosis: the Aragon Workers' Health Study (AWHS)

BACKGROUND

Ultra-processed food (UPF) consumption, which is increasing worldwide, has recently been associated with an increased risk of death and cardiovascular disease. We aimed to assess whether consumption of UPF is directly associated with subclinical coronary atherosclerosis in middle-aged men.

METHODS

A computed tomography scan was performed on 1876 men from the Aragon Workers' Health Study, recruited from January 2011 to December 2014, to assess coronary calcium. All participants were free of coronary heart disease. Dietary intake was collected by a validated 136-item semi-quantitative food frequency questionnaire. UPF was defined according to the NOVA classification. Associations between consumption of total energy-adjusted UPF and Coronary Calcium Agatston Score (CACS)-categorized into CACS of 0, > 0 and < 100, and ≥ 100-were cross-sectionally assessed by generalized ordered logistic regression adjusted for main confounders.

RESULTS

No coronary calcium was detected in 60.2% of the participants, whereas 10.2% had a CACS ≥ 100. A significant dose-response association was observed between energy-adjusted UPF consumption and the risk of having a CACS ≥ 100, when compared with those in the lowest CACS categories (CACS of 0 together with CACS > 0 and < 100). The fully adjusted ORs (95% CI) of having a CACS ≥ 100 across quartiles of energy-adjusted UPF consumption (approximately 100 g/day in the lowest quartile (ref.) and 500 g/day in the highest) were 1.00 (ref.), 1.50 (0.93, 2.42), 1.56 (0.96, 2.52), and 2.00 (1.26, 3.16), p trend .005.

CONCLUSION

In this middle-aged worker's sample, approximately 500 g/day of UPF consumption was associated with a 2-fold greater prevalence of subclinical coronary atherosclerosis than consuming only 100 g/day, independently of total energy intake and other well-established cardiovascular risk factors.

Development and validation of a quantitative food frequency questionnaire to assess dietary intake among Lebanese adults

BACKGROUND

The food frequency questionnaire (FFQ) is the most frequently used method to assess dietary intake in epidemiological studies evaluating diet-disease association. The objective of this study was to validate a FFQ for use among Lebanese adults by evaluating various facets of validity and reproducibility.

METHODS

The quantitative 164-items FFQ was validated against the average of six 24-h dietary recalls (DRs) in a sample of 238 Lebanese adults. Reproducibility of the FFQ was assessed by administering it twice within 1 month' time interval.

RESULTS

Positive statistically significant Pearson correlations were observed in most macro and micronutrients between the FFQ and the six 24-h DRs, ranging from 0.16 to 0.65, with two thirds of the correlation coefficients exceeding 0.3. Energy, gender, and age-adjusted statistically significant Pearson correlation coefficients ranged from 0.14 to 0.64, with two thirds of the coefficients exceeding 0.2. Intakes from the FFQ were mostly higher than those of the 24-h DRs. Mean percent difference between nutrient intakes from both dietary methods decreased remarkably after using energy-adjusted mean intakes. Values were acceptable to good for all macronutrients and several micronutrients. Cross-classification analysis revealed that around 64.3 to 83.9% of participants were classified into the same and adjacent quartile whereas grossly misclassified proportions ranged from 3.7 to 12.2%. Weighted kappa values ranged from 0.02 to 0.36 with most of them exceeding 0.2. In indirect validity analysis, key nutrient mean intakes estimated from the six 24-h DRs were significantly positively associated with tertiles of food groups derived from the FFQ. Bland Altman plots showed that the majority of data points fell within the limits of agreement (LOA) for all nutrients. As for reproducibility analysis, ICC values were all statistically significant ranging from 0.645 to 0.959 and Bland Altman plots confirmed these results.

CONCLUSIONS

Based on various aspects of validity and reproducibility, and an extensive range of statistical tests, the present FFQ developed for a Lebanese community is an acceptable tool for dietary assessment and is useful for evaluating diet-disease associations in future studies.

A new self-administered semi-quantitative food frequency questionnaire to estimate nutrient intake among Italian adults: development design and validation process

Food Frequency Questionnaires (FFQs) are valuable research tools in nutritional epidemiology. This study aimed to develop and validate a new semi-quantitative FFQ, specifically designed for the Italian population and best fitted for self-administration. During the development process, we adapted to Italian needs the validated FFQ proposed by the Fred Hutchinson Cancer Research Center, revising food items, food frequency scale, portion sizes, and time frame. To assess the validity of the proposed FFQ, we compared the estimated daily intake using FFQ with the mean of 3-day food diaries and one 24-hour recall (considered as reference method). The validation process was conducted among a cohort of 51 healthy subjects enrolled in a clinical trial. Four statistical tests were applied on 23 estimated nutrient intakes. Spearman's coefficients ranged from 0.223 (sodium) to 0.748 (alcohol) and were good (≥0.50) and acceptable (0.20-0.49) for 7 and 16 nutrients, respectively. Cross classification showed a good agreement (≥50% in the same tertile or ≤10% in the opposite tertile) for 7 nutrients. The weighted Cohen's kappa values indicated an acceptable outcome (0.20-0.60) for 13 nutrients. Bland Altman plots did not show heteroscedasticity in the error terms, despite the presence of a bias. Our study provided a new Italian semi-quantitative FFQ for self-administration with an acceptable validation level. Its definitive release requires additional refinements and efforts.

Associations between major dietary patterns and anxiety in middle-aged adults in eastern China

OBJECTIVE

The current study aimed to evaluate the association of major dietary patterns with anxiety in middle-aged adults in eastern China.

DESIGN

Dietary intake was assessed using a semi-quantitative FFQ. Binary logistic regression analysis was used to estimate OR and 95 % CI for anxiety according to quartiles of each dietary pattern score.

SETTING

Evidence regarding the relationship between dietary patterns and anxiety in the Chinese population is scarce.

PARTICIPANTS

The study participants were 1360 Chinese adults aged 45-59 years, who participated in a health survey at the time of periodic check-up in the city of Linyi, Shandong Province, China.

RESULTS

Four major dietary patterns were identified by factor analysis: traditional Chinese, western, grains-vegetables and high-salt diets. After adjusting for potential confounders, participants in the highest quartile of the western pattern had greater odds for anxiety, compared with those in the lowest quartile (OR 1·35, 95 % CI 1·000, 3·086, P < 0·05). In contrast, participants in the highest quartile of the grains-vegetables pattern had lower odds for anxiety than did those in the lowest quartile (OR 0·78, 95 % CI 0·574, 1·000, P < 0·05). Moreover, no significant associations were observed between the traditional Chinese and high-salt patterns and the risk of anxiety.

CONCLUSIONS

Our findings indicate that the western pattern is associated with an increased risk, and the grains-vegetables pattern is associated with a decreased risk of anxiety.

Validation of a food frequency questionnaire as a tool for assessing dietary intake in cardiovascular disease research and surveillance in Bangladesh

BACKGROUND

Cardiovascular disease (CVD) has emerged as a major public health concern in Bangladesh. Diet is an established risk factor for CVD but a tool to assess dietary intake in Bangladesh is lacking. This study aimed to validate a food frequency questionnaire (FFQ) using the 24-h dietary recall method and corresponding nutritional biological markers among rural and urban populations of Bangladesh.

METHOD

Participants of both genders aged 18-60 years were included in the analysis (total n = 146, rural n = 94 and urban n = 52). Two FFQs of 166 items were administered three-months apart, during which time three 24-h dietary recalls were also completed. Participants were asked to recall their frequency of consumption over the preceding 3 months. Urine and blood samples were collected for comparison between FFQ-estimates of nutrients and their corresponding biomarkers. Methods were compared using unadjusted, energy-adjusted, de-attenuated correlation coefficients, 95% limits of agreement (LOA) and quartile classification.

RESULTS

Fair to moderate agreement for ranking energy, macro and micronutrients into quartiles was observed (weighted k value ranged from 0.22 to 0.58; p < 0.001 for unadjusted data) except for vitamin D (weighted k - 0.05) and zinc (weighted k 0.09). Correlation coefficients of crude energy, macronutrients and common micronutrients including vitamin E, thiamine, riboflavin, niacin, pyridoxine, folate, iron, magnesium, phosphorus, potassium, and sodium were moderately good, ranging from 0.42 to 0.78; p < 0.001 but only fair for vitamin A, β carotene and calcium (0.31 to 0.38; p < 0.001) and poor for vitamin D and zinc (0.02 and 0.16; p = ns, respectively). Energy-adjusted correlations were generally lower except for fat and vitamin E, and in range of - 0.017 (for calcium) to 0.686 (for fat). De-attenuated correlations were higher than unadjusted and energy- adjusted, and significant for all nutrients except for vitamin D (0.017) to 0.801 (for carbohydrate). The Bland Altman tests demonstrated that most of the coefficients were positive which indicated that FFQ provided a greater overestimation at higher intakes. More than one in three participants appeared to overestimate their food consumption based on the ratio of energy intake to basal metabolic rate cut points suggested by Goldberg. Absolute intake of macronutrients was 1.5 times higher and for micronutrients it ranged from 1.07 (sodium) to 26 times (Zinc). FFQ estimates correlated well for sodium (0.32; p < 0.001), and vitamin D (0.20; p = 0.017) with their corresponding biomarkers and iron (0.25; p = 0.003) with serum ferritin for unadjusted data. Folate, iron (with haemoglobin) and total protein showed inverse association; and fat and potassium showed poor correlation with their corresponding biomarkers for unadjusted data. However, folate showed significant positive correlation (0.189; p = 0.025) with biomarker after energy adjustment.

CONCLUSION

Although FFQ showed overestimation for absolute intake in comparison with 24-h recalls, the validation study demonstrated acceptable agreement for ranking dietary intakes from FFQ with 24-h recall methods and some biomarkers and therefore could be considered as a tool to measure dietary intake for research and CVD risk factors surveillance in Bangladesh. The instrument may not be appropriate for monitoring population adherence to recommended intakes because of the overestimation.

Mendel's laws, Mendelian randomization and causal inference in observational data: substantive and nomenclatural issues

We respond to criticisms of Mendelian randomization (MR) by Mukamal, Stampfer and Rimm (MSR). MSR consider that MR is receiving too much attention and should be renamed. We explain how MR links to Mendel's laws, the origin of the name and our lack of concern regarding nomenclature. We address MSR's substantive points regarding MR of alcohol and cardiovascular disease, an issue on which they dispute the MR findings. We demonstrate that their strictures with respect to population stratification, confounding, weak instrument bias, pleiotropy and confounding have been addressed, and summarise how the field has advanced in relation to the issues they raise. We agree with MSR that "the hard problem of conducting high-quality, reproducible epidemiology" should be addressed by epidemiologists. However we see more evidence of confrontation of this issue within MR, as opposed to conventional observational epidemiology, within which the same methods that have demonstrably failed in the past are simply rolled out into new areas, leaving their previous failures unexamined.

Assessing diet in European populations using national dietary surveys

The WHO encourages countries to conduct national dietary surveys (NDS) to inform preventative policies targeting malnutrition and noncommunicable diseases. Previous reviews have found inadequate nutrient intakes and survey provision across Europe. This research is the first to provide an updated review of NDS provision within the whole WHO European Region, across the lifecourse, with reference to disadvantaged groups, obesity and nutrients of concern. Over a third of WHO European countries, mainly Central and Eastern European countries (CEEC), had no identifiable NDS. Where countries reported nutrient intakes, poor WHO recommended nutrient intake attainment was Europe-wide across the lifecourse, particularly in CEEC. Lower educated individuals had poorer diet quality. However, heterogeneity in age group sampled, dietary assessment method, nutrient composition database and under-reporting hindered inter-country comparisons. Average population trans fatty acid intakes below WHO recommended limits may hide inequalities in disadvantaged groups; legislative bans may help alleviate this. There were few associations between NDS-derived consumed food portion size (FPS) and BMI. However, consumed FPS was greater than on-pack serving-size in the majority of foods studied. This review illustrates how NDS can generate information on diet, nutrient intakes and the food environment. However, to enable valid inter-country comparisons, countries should be encouraged to conduct and report harmonised NDS, particularly in the age groups sampled, dietary assessment methodology, nutrient range, underpinning food composition database and treatment of under-reporters. This will aid effective, coordinated policy development that can have a real impact on dietary improvement, on a population and subgroup level, throughout Europe.

Design and validation of a food frequency questionnaire (FFQ) for the nutritional evaluation of food intake in the Peruvian Amazon

BACKGROUND

Food frequency questionnaires (FFQs) are dietary surveys widely used in studies of nutritional epidemiology because they are inexpensive, easy to complete and provide significant information on dietary intake over a long period of time. FFQs should be written specifically for each study group since diet may be influenced by ethnicity, culture, economic status and environmental factors. The aim of the authors on this work was to design and validate a food frequency questionnaire for the Peruvian Amazon population.

METHODS

Three hundred three individuals were selected and completed three 24-h recalls (R24). Two FFQs were conducted on two different occasions (FFQ.1 and FFQ.2). The validity of the FFQ was evaluated by comparing the relationship between the average daily nutrient intake estimated by the FFQs and that obtained by the three R24. The reproducibility was measured by comparing the mean nutrient intake of the two FFQs carried out. The correlations were assessed using the Pearson correlation coefficient, the intraclass correlation coefficient (ICC), the Lin correlation coefficient (CCC) and the Bland-Altman plot.

RESULTS

The results obtained to establish the validity showed a high correlation, with an average Pearson's correlation coefficient of 0.70, a CCI of 0.65 and a CCC of 0.60. Approximately 60% of the nutrients had a CCC above 0.60. In terms of reproducibility, better results were obtained, with an average Pearson's correlation coefficient of 0.67, 0.64 for CCI and 0.58 for CCC.

CONCLUSIONS

The correlation coefficients show good validity and reproducibility, and therefore, the FFQ we have developed may be considered a useful and valid tool to estimate the dietary intake of the Peruvian Amazon population.

The association of dietary patterns and carotid intima-media thickness: A synthesis of current evidence

AIMS

Dietary pattern (DP) analysis has emerged as a holistic method to understand the effects of food intake on health outcomes. Though dietary intake has been associated with cardiovascular disease, the association of DPs and carotid intima-media thickness (CIMT), a robust early marker of cardiovascular disease progression has not been comprehensively investigated. This study systematically explores the association of a posteriori and a priori DPs and CIMT.

DATA SYNTHESIS

Through a systematic search of MEDLINE, CINAHL, and Web of Science, twenty studies that derived DPs using a posteriori or a priori methods with CIMT as an outcome were included. Four cross-sectional studies and 1 cohort paper reported a statistically significant association between increased consumption of 'unhealthy' foods (i.e processed meat, soda drinks and refined grain) and increased CIMT. While four cross-sectional studies reported a statistically significant association of DPs characterized by increased consumption of 'healthy' foods (i.e fruit and vegetables, fish) and decreased CIMT. DPs derived from each study varied depending on derivation method, study design and use of dietary data collection method.

CONCLUSION

Findings from this review are generally supportive of a trend between DPs with higher consumption of 'healthy' foods and lower consumption of 'unhealthy' foods and decreased CIMT; however, the association was largely not statistically significant. Evidence was overwhelmingly heterogeneous due to differences seen in DPs based on location and culture, sample characteristics and adjustment for confounders. Long-term prospective observational and interventional studies with standardized sample selection and dietary data collection are needed to significantly establish the role of DPs on CIMT.

Associations of sugar intake with anthropometrics in children from ages 2 until 8 years in the EU Childhood Obesity Project

PURPOSE

We determined the association of total sugar intake with body weight and fat mass in children on an energy-equivalent basis and potential changes in the association from 2 to 8 years of age.

METHODS

Data were available from the Childhood Obesity Project Trial initiated in 2002. Sugar intake was measured by 3-day weighed food protocols at 2, 3, 4, 5, 6, and 8 years of age. Body mass index (BMI) and fat mass index (FMI) were available at the same time points. To investigate the association of sugar intake with anthropometrics over time, linear mixed models were applied. Odds ratios for having a high BMI or FMI (above one standard deviation) were estimated by logistic random-effects models. To control for total energy intake, the residual method was chosen and models were additionally adjusted for total energy intake.

RESULTS

Data were available for 809 children with in total 2846 observations. In an isocaloric model, an increase of 100 kcal from sugar per day was significantly associated with lower zBMI (- 0.033; 95% CI -0.061, - 0.005) and zFMI (- 0.050; 95% CI - 0.089, - 0.011). In addition, a 100 kcal higher sugar intake was related to lower odds of having a high zBMI (OR 0.743; 95% CI 0.611, 0.903).

CONCLUSION

This study provides no indication that increased total sugar intake positively affects BMI on an energy-equivalent basis. Whether the negative association of sugar is due to physiological effects or points more to macronutrient preferences or a reporting bias (lower sugar intake) in children with higher BMI can be debated.

CLINICAL TRIAL REGISTRY

ClinicalTrials.gov Identifier: NCT00338689; Registered: June 19, 2006. URL: http://clinicaltrials.gov/ct2/show/NCT00338689?term=NCT00338689&rank=1 .

Association between dietary patterns and chronic kidney disease in a middle-aged Chinese population

OBJECTIVE

To explore the relationship between dietary patterns and risk of chronic kidney disease (CKD) in Chinese adults aged 45-59 years.

DESIGN

Dietary data were collected using a semi-quantitative FFQ. Factor analysis was used to identify the major dietary patterns. Logistic regression models were applied to clarify the association between dietary patterns and the risk of CKD.

SETTING

The present study population was a part of the population-based Nutrition and Health Study performed in the city of Hangzhou, Zhejiang Province, eastern China.

PARTICIPANTS

A total of 2437 eligible participants (45-59 years) were enrolled in the present cross-sectional study from June 2015 to December 2016.

RESULTS

Three major dietary patterns were identified: 'traditional southern Chinese', 'Western' and 'grains-vegetables' patterns, collectively accounting for 25·6 % of variance in the diet. After adjustment for potential confounders, participants in the highest quartile of the Western pattern had greater odds for CKD (OR = 1·83, 95 % CI 1·21, 2·81; P < 0·05) than those in the lowest quartile. Compared with the lowest quartile of the grains-vegetables pattern, the highest quartile had lower odds for CKD (OR = 0·84, 95 % CI 0·77, 0·93; P < 0·05). In addition, there was no significant association between the traditional southern Chinese pattern and risk of CKD (P > 0·05).

CONCLUSIONS

Our results suggest that the Western pattern is associated with an increased risk, whereas the grains-vegetables pattern is associated with a reduced risk for CKD. These findings can guide dietary interventions for the prevention of CKD in a middle-aged Chinese population.