Glycemic Index, Glycemic Load and Dyslipidemia in Adolescents from Chiapas, Mexico.

Cardiovascular disease risk throughout the life course is increased by abnormal blood lipid levels in youth. The dietary glycemic index (GI) and glycemic load (GL) during adolescence might be related to abnormal blood lipids. This study aimed to analyze the association between dietary GI, GL and dyslipidemia in adolescents from two marginalized regions of Chiapas, Mexico. A cross-sectional study was conducted with 213 adolescents. Food intake was assessed using 24 h recalls. The association between dyslipidemia and dietary GI or GL was tested by using logistic regression models. Low HDL-c was the most prevalent risk factor (47.4%), followed by hypertriglyceridemia (25.4%). In this population, overall dietary GI was not associated with dyslipidemia. A high dietary GL was associated with 2.39 higher odds of low HDL-c (95% CI: 1.21-4.74) when compared to low GL. Female adolescents with high dietary GL had 3.20 higher odds of hypertriglyceridemia (95% CI: 1.03-9.88), whereas no association was found for males. No associations were observed between overall dietary GL and total cholesterol or LDL-c. In adolescents from urban and rural communities in Chiapas, a high dietary GL was associated with a detrimental effect on HDL-c. In female adolescents, high GL was associated with hypertriglyceridemia.

Sociodemographic inequalities in cardiovascular risk factors among adolescents from indigenous areas in Chiapas, Mexico.

This study was aimed to determine the prevalence of cardiovascular risk factors among different sociodemographic groups of adolescents from indigenous communities in Chiapas, Mexico. A cross-sectional prevalence study was performed in urban and rural communities in the Tzotzil-Tzeltal and Selva regions of Chiapas. A sample of 253 adolescents was studied, of whom 48% were girls and 52% were boys. A descriptive analysis of quantitative variables was performed using measures of central tendency and dispersion. The prevalence of cardiovascular risk factors stratified by sex, geographical area, years of schooling, and ethnicity of the mothers was estimated. The prevalence of cardiovascular risk factors was analyzed in relation to the sociodemographic characteristics of the study population. Low HDL-c (51%) was the predominant cardiovascular risk factor. Girls had a higher prevalence of abdominal obesity, hypertriglyceridemia, and borderline total cholesterol than boys. High diastolic blood pressure was more prevalent in boys. Adolescents from urban areas had a higher prevalence of overweight/obesity and insulin resistance than adolescents from rural areas. The prevalence of overweight/obesity and abdominal obesity was higher in adolescents whose mothers had ≥ 7 years of schooling compared with adolescents with less educated mothers. Differences by maternal ethnicity also influenced the prevalence of insulin resistance. Among the main findings, this study associated sociodemographic and geographical inequalities with cardiovascular risk factors. Promoting a healthy lifestyle for this young population is absolutely necessary to prevent cardiovascular diseases in adulthood.

Sociodemographic inequalities in cardiovascular risk factors among adolescents from indigenous areas in Chiapas, Mexico / Desigualdades sociodemográficas como factores de riesgo cardiovascular para adolescentes de zonas indígenas de Chiapas, México / Desigualdades sociodemográficas como fatores de risco cardiovascular para adolescentes de áreas indígenas de Chiapas, México

Abstract: This study was aimed to determine the prevalence of cardiovascular risk factors among different sociodemographic groups of adolescents from indigenous communities in Chiapas, Mexico. A cross-sectional prevalence study was performed in urban and rural communities in the Tzotzil-Tzeltal and Selva regions of Chiapas. A sample of 253 adolescents was studied, of whom 48% were girls and 52% were boys. A descriptive analysis of quantitative variables was performed using measures of central tendency and dispersion. The prevalence of cardiovascular risk factors stratified by sex, geographical area, years of schooling, and ethnicity of the mothers was estimated. The prevalence of cardiovascular risk factors was analyzed in relation to the sociodemographic characteristics of the study population. Low HDL-c (51%) was the predominant cardiovascular risk factor. Girls had a higher prevalence of abdominal obesity, hypertriglyceridemia, and borderline total cholesterol than boys. High diastolic blood pressure was more prevalent in boys. Adolescents from urban areas had a higher prevalence of overweight/obesity and insulin resistance than adolescents from rural areas. The prevalence of overweight/obesity and abdominal obesity was higher in adolescents whose mothers had ≥ 7 years of schooling compared with adolescents with less educated mothers. Differences by maternal ethnicity also influenced the prevalence of insulin resistance. Among the main findings, this study associated sociodemographic and geographical inequalities with cardiovascular risk factors. Promoting a healthy lifestyle for this young population is absolutely necessary to prevent cardiovascular diseases in adulthood.

Resumen: El objetivo de este estudio fue estimar la prevalencia de los factores de riesgo cardiovascular entre diferentes grupos sociodemográficos de adolescentes de comunidades indígenas de Chiapas, México. Se realizó un estudio transversal de prevalencia en comunidades urbanas y rurales de las regiones Tzotzil-Tzeltal y Selva, en Chiapas. Participó una muestra de 253 adolescentes, en la cual el 48% eran niñas y el 52% niños. Se realizó un análisis descriptivo de las variables cuantitativas utilizando medidas de tendencia central y dispersión. Se estimó la prevalencia de los factores de riesgo cardiovascular, estratificados por sexo, área geográfica, nivel de estudios y etnia de las madres. Se analizó la prevalencia de los factores de riesgo cardiovascular con relación a las características sociodemográficas de la población estudiada. El HDL-c bajo (51%) fue el factor de riesgo cardiovascular predominante. Se observó una mayor prevalencia de obesidad abdominal, hipertrigliceridemia y colesterol total en las niñas que en los niños. La alta presión arterial diastólica prevaleció en los niños. Los adolescentes del área urbana tuvieron una mayor prevalencia de sobrepeso/obesidad y resistencia a la insulina que los del área rural. La prevalencia de sobrepeso/obesidad y obesidad abdominal fue mayor en los adolescentes cuyas madres tenían nivel de estudios ≥ 7 años que aquellos cuyas madres tenían bajo nivel de estudios. Las diferencias en la etnicidad materna también influyeron en la prevalencia de resistencia a la insulina. Entre las principales conclusiones de este estudio, se destacan las desigualdades sociodemográficas y geográficas entre los factores de riesgo cardiovascular. La promoción de un estilo de vida saludable entre la población joven es lo indicado para prevenir las enfermedades cardiovasculares en la edad adulta.

Resumo: O objetivo deste estudo foi determinar a prevalência de fatores de risco cardiovascular entre diferentes grupos sociodemográficos de adolescentes de comunidades indígenas em Chiapas, México. Foi realizado um estudo transversal de prevalência em comunidades urbanas e rurais das regiões de Tzotzil-Tzeltal e Selva de Chiapas. Foi estudada uma amostra de 253 adolescentes, sendo 48% meninas e 52% meninos. Foi realizada uma análise descritiva das variáveis quantitativas por meio de medidas de tendência central e dispersão. Foram estimadas as prevalências de fatores de risco cardiovascular, estratificadas por sexo, área geográfica, escolaridade e etnia das mães. A prevalência dos fatores de risco cardiovascular foi analisada em relação às características sociodemográficas da população estudada. O HDL-c baixo (51%) foi o fator de risco cardiovascular predominante. Prevalências mais elevadas de obesidade abdominal, hipertrigliceridemia e colesterol total limítrofe foram mais observadas em meninas do que em meninos. A pressão arterial diastólica elevada prevaleceu nos meninos. Adolescentes da área urbana apresentaram prevalências de sobrepeso/obesidade e resistência à insulina maiores do que os da área rural. A prevalência de sobrepeso/obesidade e obesidade abdominal foi maior nos adolescentes cujas mães possuíam escolaridade ≥ 7 anos do que naqueles indivíduos cujas mães tinham baixa escolaridade. As diferenças de etnia das mães também foram observadas na prevalência de resistência à insulina. Dentre as principais conclusões, foram encontradas, neste estudo, desigualdades sociodemográficas e geográficas entre fatores de risco cardiovascular. Promover estilos de vida saudáveis entre a população jovem é o ideal para prevenir doenças cardiovasculares na vida adulta.

Refractive status of patients attending eye clinics of the Public Health System from Aguascalientes, Mexico

Purpose: This paper aims to evaluate the prevalence of REs in a clinic from Aguascalientes, Mexico by analysing clinical records from the local public health system. Refractive errors (REs) are quite common globally, but no data have been published regarding their frequency in clinics from Mexico. A priori, the frequency of ametropias should be high as admixture ancestry from this region is mainly European and Amerindian, the regions with high prevalence worldwide.MethodsThis cross-sectional study was conducted on 2195 subjects from records of public optometry services during the year 2018. Information obtained included age, gender, sphere, cylinder and axis. The prevalence of myopia, hyperopia and astigmatism was determined by gender and age groups in paediatric and adult patients. Chi-square testing was applied to determine significant differences in prevalence across age groups and gender. A p-value <0.05 was considered significant.ResultsIn subjects under 18 years of age, the prevalence of emmetropia, astigmatism, myopia and hyperopia was 20.1%, 51.1%, 7.0% and 11.8%, respectively. In adults, emmetropia was present at a frequency of 20.1%, while 57.1% presented astigmatism, 12.4% hyperopia and 8.6% presented myopia. A significant association was observed between the presence of REs and age and gender.ConclusionsIn this first report of prevalence of REs from western Mexico, astigmatism was the most prevalent RE in children, adolescents and adults while the least common was myopia. Important differences were found in prevalence in comparison to national and international reports. (AU)

Association of rs9939609-FTO with metabolic syndrome components among women from Mayan communities of Chiapas, Mexico.

BACKGROUND: Metabolic syndrome (MetS) is a complex cluster of risk factors, considered as a polygenic and multifactorial entity. The objective of this study was to determine the association of rs9939609-FTO polymorphism and MetS components in adult women of Mayan communities of Chiapas. METHODS: In a cross-sectional study, sociodemographic, anthropometric, clinical, and biochemical data were obtained from 291 adult women from three regions of Chiapas, Mexico. The prevalence of MetS and the allele and genotype frequencies of the rs9939609-FTO were estimated. Multivariate logistic regression models were used to assess the association of the single nucleotide polymorphism (SNP) with each of the MetS components. RESULTS: The MetS prevalence was 60%. We found a statistically significant association between rs9939609-FTO and hyperglycemia in the dominant model (OR 2.6; 95% CI 1.3-5.3; p = 0.007). CONCLUSIONS: Women from Mayan communities of Chiapas presented a high prevalence of MetS and a relevant association of the FTO variant with hyperglycemia. This is the first study carried out in these Mayan indigenous communities from Chiapas.

Refractive status of patients attending eye clinics of the Public Health System from Aguascalientes, Mexico.

PURPOSE: This paper aims to evaluate the prevalence of REs in a clinic from Aguascalientes, Mexico by analysing clinical records from the local public health system. Refractive errors (REs) are quite common globally, but no data have been published regarding their frequency in clinics from Mexico. A priori, the frequency of ametropias should be high as admixture ancestry from this region is mainly European and Amerindian, the regions with high prevalence worldwide. METHODS: This cross-sectional study was conducted on 2195 subjects from records of public optometry services during the year 2018. Information obtained included age, gender, sphere, cylinder and axis. The prevalence of myopia, hyperopia and astigmatism was determined by gender and age groups in paediatric and adult patients. Chi-square testing was applied to determine significant differences in prevalence across age groups and gender. A p-value <0.05 was considered significant. RESULTS: In subjects under 18 years of age, the prevalence of emmetropia, astigmatism, myopia and hyperopia was 20.1%, 51.1%, 7.0% and 11.8%, respectively. In adults, emmetropia was present at a frequency of 20.1%, while 57.1% presented astigmatism, 12.4% hyperopia and 8.6% presented myopia. A significant association was observed between the presence of REs and age and gender. CONCLUSIONS: In this first report of prevalence of REs from western Mexico, astigmatism was the most prevalent RE in children, adolescents and adults while the least common was myopia. Important differences were found in prevalence in comparison to national and international reports.

Intrauterine growth restriction and overweight, obesity, and stunting in adolescents of indigenous communities of Chiapas, Mexico.

BACKGROUND/OBJECTIVES: Intrauterine growth restriction (IUGR) and low-birth-weight (LBW) are determinant factors in the development of metabolic diseases in children and adolescents. To estimate the magnitude of the association between LBW and IUGR with stunting or obesity among adolescents of two indigenous regions of the southern State of Chiapas, Mexico. SUBJECTS/METHODS: We assessed a random sample of 303 adolescents selected from a birth cohort study (2003) conducted in three hospitals serving urban and rural communities of Tzotzil-Tzeltal and Selva regions of Chiapas, Mexico. Sociodemographic and anthropometric data from a sample of adolescents were correlated with their anthropometric data at birth (weight, length for age). Logistic regression models were fitted to estimate odds ratios (OR) with 95% confidence intervals to measure the magnitude of the association among the variables of interest. Models were adjusted for potential confounders. RESULTS: In all, 12% of the sample had LBW and 28.8% IUGR. In total, 29% of adolescents were overweight/obese and 21% were stunted. We found a statistically significant association between IUGR and a lower risk of being overweight/obese. A higher probability for stunting was observed for LBW and IUGR. CONCLUSIONS: Stunting and overweight/obesity prevalence in this population of adolescents was high and was associated with IUGR.

Dietary Carbohydrates and Insulin Resistance in Adolescents from Marginalized Areas of Chiapas, México.

Evidence of the role that dietary carbohydrates (total carbohydrates, dietary fiber, total sugars, dietary glycemic index (GI) and glycemic load (GL)) exerts on insulin levels in adolescents is controversial. Thus, the aim of this study was to assess the association between dietary carbohydrates and insulin resistance in adolescents from Chiapas, México. A cross-sectional study was conducted in 217 adolescents. Sociodemographic, anthropometric, dietary and biochemical data were obtained. Total carbohydrates, dietary fiber, total sugars, dietary GI and GL were calculated from 24 h recalls. Two validated cut-off points for the homeostasis model assessment of insulin resistance (HOMA-IR) were used as surrogates of insulin resistance. Fasting insulin levels ≥ 14.38 µU/mL were considered as abnormal. Multivariate logistic regression models were fitted to assess the association between tertiles of dietary carbohydrates and insulin resistance or hyperinsulinemia. In our study, adolescents with the highest dietary fiber intake had lower odds of HOMA-IR > 2.97 (OR = 0.34; 95% CI: 0.13-0.93) when adjusted for sex, age, body fat percentage and saturated fatty acids intake. No significant associations were found for the rest of the carbohydrate variables. In summary, high-fiber diets reduce the probability of insulin resistance in adolescents from marginalized areas of Chiapas, México.

Glycemic index, glycemic load, and metabolic syndrome in Mexican adolescents: a cross-sectional study from the NHNS-2012.

BACKGROUND: The role of dietary glycemic index (GI) and dietary glycemic load (GL) on metabolic syndrome (MetS) in youth populations remains unclear. The aim of the present study was to evaluate the association among dietary GI, dietary GL, and MetS and its components in Mexican adolescents. METHODS: This study was conducted within the framework of the National Health and Nutrition Survey 2012, a cross-sectional, probabilistic, population-based survey with a multistage stratified cluster sampling design. We analyzed a sample of 1346 subjects aged 12-19 years, representing 13,164,077 adolescents. Dietary habits were assessed through a validated semiquantitative food-frequency questionnaire. We assigned GI values using the International Tables of GI values. We defined MetS according to the International Diabetes Federation criteria developed for adolescents. Multiple logistic regression models were used to estimate odds ratios (ORs) and their 95% confidence intervals (CIs) to evaluate the association between categories of dietary GI and GL and the prevalence of MetS and its components. RESULTS: We observed no associations between dietary GI or GL and MetS prevalence. Female adolescents in the highest category of dietary GI had higher odds of abnormal blood pressure (OR = 3.66; 95% CI, 1.46-9.22; P for trend = 0.012). A high dietary GL was also associated with higher odds of abnormal blood pressure in female adolescents (OR = 5.67; 95% CI, 1.84-17.46; P for trend = 0.003). CONCLUSIONS: We found higher odds of abnormal blood pressure for female adolescents with a high dietary GI and dietary GL.

Glycemic index, glycemic load and invasive breast cancer incidence in postmenopausal women: The PREDIMED study.

The objective of this study was to evaluate the prospective associations between dietary glycemic index (GI) and glycemic load (GL) and the risk for invasive breast cancer incidence in postmenopausal women at high cardiovascular disease (CVD) risk. This study was conducted within the framework of the PREvención con DIeta MEDiterránea (PREDIMED) study, a nutritional intervention trial for primary cardiovascular prevention. We included 4010 women aged between 60 and 80 years who were initially free from breast cancer but at high risk for CVD disease. Dietary information was collected using a validated 137-item food frequency questionnaire. We assigned GI values using the International Tables of GI and GL values. Cases were ascertained through yearly consultation of medical records and through consultation of the National Death Index. Only cases confirmed by results from cytology tests or histological evaluation were included. We estimated multivariable-adjusted hazard ratios for invasive breast cancer risk across tertiles of energy-adjusted dietary GI/GL using Cox regression models. We repeated our analyses using yearly repeated measures of GI/GL intakes. No associations were found between baseline dietary GI/GL and invasive breast cancer incidence. The multivariable hazard ratio and 95% confidence interval (CI) for the top tertile of dietary GI was 1.02 (95% CI: 0.42-2.46) and for dietary GL was 1.00 (95% CI: 0.44-2.30) when compared with the bottom tertile. Repeated-measures analyses yielded similar results. In sensitivity analyses, no significant associations were observed for women with obesity or diabetes. Dietary GI and GL did not appear to be associated with an increased risk for invasive breast cancer in postmenopausal women at high CVD risk.

Dietary Glycemic Index and Glycemic Load Are Positively Associated with Risk of Developing Metabolic Syndrome in Middle-Aged and Elderly Adults.

OBJECTIVES: To evaluate how glycemic index (GI) and glycemic load (GL) are associated with the metabolic syndrome (MetS) and its features in middle-aged and elderly adults at high cardiovascular risk. DESIGN: Prospective, longitudinal, population-based cohort. SETTING: PREvención con DIeta MEDiterránea study. PARTICIPANTS: Men and women (N = 6,606) divided into three age groups (<65, 65-74, ≥75). MEASUREMENTS: Energy and nutrient intake was evaluated using a validated 137-item food frequency questionnaire. MetS and its features were defined in accordance with the criteria of the American Heart Association and National Heart, Lung, and Blood Institute. RESULTS: A positive association was observed between GI and MetS prevalence in the youngest and middle age groups for participants without diabetes mellitus, but no relationship was found for those with diabetes mellitus. During the median follow-up of 4.8 years, higher GI and GL were related to greater risk of MetS in the middle age group, independent of the presence of diabetes mellitus. Changes in dietary GI were associated with risk of developing the high fasting glucose component of the MetS in the oldest age category, and changes in dietary GL were associated with risk of developing abdominal obesity, hypertriglyceridemia, low high-density lipoprotein cholesterol, and high blood pressure in the youngest age category. CONCLUSION: Dietary GI and GL have a potential role in the development of MetS and associated clinical features, with particular age-dependent considerations.

Assessment of beverage intake and hydration status / Valoración de la ingesta de bebidas y el estado de hidratación

Water is the main constituent of the human body. It is involved in practically all its functions. It is particularly important for thermoregulation and in the physical and cognitive performance. Water balance reflects water intake and loss. Intake of water is done mainly through consumption of drinking water and beverages (70 to 80%) plus water containing foods (20 to 30%). Water loss is mainly due to excretion of water in urine, faeces and sweat. The interest in the type and quantity of beverage consumption is not new, and numerous approaches have been used to assess beverage intake, but the validity of these approaches has not been well established. There is no standardized questionnaire developed as a research tool for the evaluation of water intake in the general population. Sometimes, the information comes from different sources or from different methodological characteristics which raises problems of the comparability. In the European Union, current epidemiological studies that focus exclusively on beverage intake are scarce. Biomarkers of intake are able to objectively assess dietary intake/status without the bias of self-reported dietary intake errors and also overcome the problem of intra-individual diet variability. Furthermore, some methods of measuring dietary intake used biomarkers to validate the data it collects. Biological markers may offer advantages and be able to improve the estimates of dietary intake assessment, which impact into the statistical power of the study. There is a surprising paucity of studies that systematically examine the correlation of beverages intake and hydration biomarker in different populations. A pilot investigation was developed to evaluate the comparative validity and reliability of newly developed interactive multimedia (IMM) versions compared to validated paper-administered (PP) versions of the Hedrick et al. beverage questionnaire. The study showed that the IMM appears to be a valid and reliable measure to assess habitual beverage intake. Similar study was developed in China, but in this case, the use of Smartphone technology was employed for beverage assessment. Conclusion: The methodology for measuring beverage intake in population studies remains controversial. There are few validated and reproducible studies, so there is still lacking an ideal method (ie, short, easy to administer, inexpensive and accurate) in this regard. Clearly, this is an area of scientific interest that is still in development and seems to be very promising for improving health research (AU)

El agua es el principal constituyente del cuerpo humano. Está implicado en prácticamente la totalidad de sus funciones. Es especialmente importante en la termorregulación y en el rendimiento físico y cognitivo. El balance de agua refleja la ingesta y la pérdida de agua. La ingesta se realiza principalmente a través del consumo de agua potable y de bebidas (70 a 80%) más el agua que contienen los alimentos (20 a 30%). La pérdida de agua se realiza gracias a su excreción a través de la orina, las heces y el sudor. El interés por el tipo y la cantidad de bebidas consumidas no es nuevo, y numerosos enfoques se han utilizado para evaluarla, pero la validez de estos enfoques no se han establecido correctamente. Aún no existe, en población general, un cuestionario estandarizado desarrollado como herramienta de investigación para la evaluación de la ingesta de agua. El uso de información de diferentes fuentes y diferentes características metodológicas plantea problemas de comparabilidad entre estudios. En Europa los estudios epidemiológicos actuales que se centran exclusivamente en el consumo de bebidas son escasos. Los biomarcadores de ingesta permiten evaluar objetivamente la ingesta dietética sin el sesgo producido por los errores del auto-reporte. Además permiten superar el problema de la variabilidad intra-individual. Algunos métodos para medir ingesta alimentaria utilizan biomarcadores para validar los datos que recoge. Los marcadores biológicos ofrecen ventajas y son capaces de mejorar las estimaciones de la evaluación de ingesta dietética. Sin embargo, existen muy pocos estudios que examinen sistemáticamente la correlación entre la ingesta de bebidas y los biomarcadores de hidratación en diferentes poblaciones. Utilizando el cuestionario de bebidas de Hedrick y col. se realizó un estudio piloto para evaluar la validez y fiabilidad de un modelo multimedia interactivo (IMM) y para compararlo con una versión en papel-auto administrado (PP). El estudio mostró que el IMM parece ser un modelo válido y fiable para evaluar la ingesta de bebidas habitual. Un estudio similar se realizó en China, pero en este caso, se empleó para evaluar ingesta de bebidas la tecnología Smartphone. Conclusión: La metodología para valorar el consumo de bebidas en estudios poblacionales sigue siendo un tema controvertido. Existen pocos estudios validados y reproducibles, por lo que todavía no se dispone de un método ideal (corto, fácil de administrar, económico y preciso). Esta es un área de interés científico que aún está en desarrollo y que parece ser muy prometedora para mejorar las investigaciones en el área de la salud (AU)

Misreporting in nutritional surveys: methodological implications / Infradeclaración en las encuestas alimentarias: implicaciones metodológicas

The reliability of the information collected in dietary assessment can be affected by different factors. One of the main sources of error in dietary assessment is misreporting which encompass under- and overreporting. Underreporting of food intake is one of the major problems in the assessment of habitual dietary intake. Physical and psychosocial characteristics that are related to energy underreporting include sex, age, weight, BMI, fear of negative evaluation and dieting among others. At present, diverse reference methods are employed to verify the results of dietary assessment and double labelled water is used as the gold standard method. Underreporting affects the estimation of nutrient intake and also alters associations between diet and disease assessed in epidemiological studies. Therefore, underreporting has to be considered and addressed by researchers through development and improvement of dietary intake adjustment methods, and taking advantage of the new technologies for assessing dietary intake in order to minimize underreporting bias (AU)

La fiabilidad de la información recogida en la evaluación dietética puede verse afectada por diferentes factores. Una de las principales fuentes de error en la evaluación de la dieta es la declaración errónea de consumo de alimentos, que abarca la infradeclaración y sobredeclaración de la dieta. La infradeclaración de la ingesta de alimentos es uno de los principales problemas en la evaluación de la ingesta dietética habitual. Las características físicas y psicosociales que están relacionadas con la infradeclaración de energía incluyen el sexo, edad, peso, índice de masa corporal, el miedo a la evaluación negativa y estar bajo un régimen de dieta, entre otros. En la actualidad, se emplean diversos métodos de referencia para verificar los resultados de la evaluación dietética, no obstante, el método estándar es el agua doblemente marcada. La infradeclaración afecta a la estimación de la ingesta de nutrientes y también altera las asociaciones entre dieta y enfermedades en estudios epidemiológicos. Por lo tanto, la infradeclaración tiene que ser considerada y abordada por los investigadores a través del desarrollo y la mejora de los métodos de ajuste de la dieta y el aprovechamiento de las nuevas tecnologías para la evaluación de la ingesta dietética con el fin de minimizar el sesgo ocasionado por la infradeclaración (AU)

Assessment of beverage intake and hydration status.

UNLABELLED: Water is the main constituent of the human body. It is involved in practically all its functions. It is particularly important for thermoregulation and in the physical and cognitive performance. Water balance reflects water intake and loss. Intake of water is done mainly through consumption of drinking water and beverages (70 to 80%) plus water containing foods (20 to 30%). Water loss is mainly due to excretion of water in urine, faeces and sweat. The interest in the type and quantity of beverage consumption is not new, and numerous approaches have been used to assess beverage intake, but the validity of these approaches has not been well established. There is no standardized questionnaire developed as a research tool for the evaluation of water intake in the general population. Sometimes, the information comes from different sources or from different methodological characteristics which raises problems of the comparability. In the European Union, current epidemiological studies that focus exclusively on beverage intake are scarce. Biomarkers of intake are able to objectively assess dietary intake/status without the bias of self-reported dietary intake errors and also overcome the problem of intra-individual diet variability. Furthermore, some methods of measuring dietary intake used biomarkers to validate the data it collects. Biological markers may offer advantages and be able to improve the estimates of dietary intake assessment, which impact into the statistical power of the study. There is a surprising paucity of studies that systematically examine the correlation of beverages intake and hydration biomarker in different populations. A pilot investigation was developed to evaluate the comparative validity and reliability of newly developed interactive multimedia (IMM) versions compared to validated paper-administered (PP) versions of the Hedrick et al. beverage questionnaire. The study showed that the IMM appears to be a valid and reliable measure to assess habitual beverage intake. Similar study was developed in China, but in this case, the use of Smartphone technology was employed for beverage assessment. CONCLUSION: The methodology for measuring beverage intake in population studies remains controversial. There are few validated and reproducible studies, so there is still lacking an ideal method (ie, short, easy to administer, inexpensive and accurate) in this regard. Clearly, this is an area of scientific interest that is still in development and seems to be very promising for improving health research.

El agua es el principal constituyente del cuerpo humano. Está implicado en prácticamente la totalidad de sus funciones. Es especialmente importante en la termorregulación y en el rendimiento físico y cognitivo. El balance de agua refleja la ingesta y la pérdida de agua. La ingesta se realiza principalmente a través del consumo de agua potable y de bebidas (70 a 80%) más el agua que contienen los alimentos (20 a 30%). La pérdida de agua se realiza gracias a su excreción a través de la orina, las heces y el sudor. El interés por el tipo y la cantidad de bebidas consumidas no es nuevo, y numerosos enfoques se han utilizado para evaluarla, pero la validez de estos enfoques no se han establecido correctamente. Aún no existe, en población general, un cuestionario estandarizado desarrollado como herramienta de investigación para la evaluación de la ingesta de agua. El uso de información de diferentes fuentes y diferentes características metodológicas plantea problemas de comparabilidad entre estudios. En Europa los estudios epidemiológicos actuales que se centran exclusivamente en el consumo de bebidas son escasos. Los biomarcadores de ingesta permiten evaluar objetivamente la ingesta dietética sin el sesgo producido por los errores del auto-reporte. Además permiten superar el problema de la variabilidad intra-individual. Algunos métodos para medir ingesta alimentaria utilizan biomarcadores para validar los datos que recoge. Los marcadores biológicos ofrecen ventajas y son capaces de mejorar las estimaciones de la evaluación de ingesta dietética. Sin embargo, existen muy pocos estudios que examinen sistemáticamente la correlación entre la ingesta de bebidas y los biomarcadores de hidratación en diferentes poblaciones. Utilizando el cuestionario de bebidas de Hedrick y col. se realizó un estudio piloto para evaluar la validez y fiabilidad de un modelo multimedia interactivo (IMM) y para compararlo con una versión en papel-auto administrado (PP). El estudio mostró que el IMM parece ser un modelo válido y fiable para evaluar la ingesta de bebidas habitual. Un estudio similar se realizó en China, pero en este caso, se empleó para evaluar ingesta de bebidas la tecnología Smartphone. Conclusión: La metodología para valorar el consumo de bebidas en estudios poblacionales sigue siendo un tema controvertido. Existen pocos estudios validados y reproducibles, por lo que todavía no se dispone de un método ideal (corto, fácil de administrar, económico y preciso). Esta es un área de interés científico que aún está en desarrollo y que parece ser muy prometedora para mejorar las investigaciones en el área de la salud.

Misreporting in nutritional surveys: methodological implications.

The reliability of the information collected in dietary assessment can be affected by different factors. One of the main sources of error in dietary assessment is misreporting which encompass under- and overreporting. Underreporting of food intake is one of the major problems in the assessment of habitual dietary intake. Physical and psychosocial characteristics that are related to energy underreporting include sex, age, weight, BMI, fear of negative evaluation and dieting among others. At present, diverse reference methods are employed to verify the results of dietary assessment and double labelled water is used as the gold standard method. Underreporting affects the estimation of nutrient intake and also alters associations between diet and disease assessed in epidemiological studies. Therefore, underreporting has to be considered and addressed by researchers through development and improvement of dietary intake adjustment methods, and taking advantage of the new technologies for assessing dietary intake in order to minimize underreporting bias.

La fiabilidad de la información recogida en la evaluación dietética puede verse afectada por diferentes factores. Una de las principales fuentes de error en la evaluación de la dieta es la declaración errónea de consumo de alimentos, que abarca la infradeclaración y sobredeclaración de la dieta. La infradeclaración de la ingesta de alimentos es uno de los principales problemas en la evaluación de la ingesta dietética habitual. Las características físicas y psicosociales que están relacionadas con la infradeclaración de energía incluyen el sexo, edad, peso, índice de masa corporal, el miedo a la evaluación negativa y estar bajo un régimen de dieta, entre otros. En la actualidad, se emplean diversos métodos de referencia para verificar los resultados de la evaluación dietética, no obstante, el método estándar es el agua doblemente marcada. La infradeclaración afecta a la estimación de la ingesta de nutrientes y también altera las asociaciones entre dieta y enfermedades en estudios epidemiológicos. Por lo tanto, la infradeclaración tiene que ser considerada y abordada por los investigadores a través del desarrollo y la mejora de los métodos de ajuste de la dieta y el aprovechamiento de las nuevas tecnologías para la evaluación de la ingesta dietética con el fin de minimizar el sesgo ocasionado por la infradeclaración.

Dietary glycaemic index and glycaemic load in a rural elderly population (60-74 years of age) and their relationship with cardiovascular risk factors.

PURPOSE: To examine the association between dietary glycaemic index (GI) and dietary glycaemic load (GL) with cardiovascular disease (CVD) risk factors in a rural elderly population. METHODS: A cross-sectional study was conducted in 343 subjects (60-74 years) residing in a Spanish rural area (Priego de Córdoba). Subjects were selected using stratified random sampling. Food intake was assessed using a validated food frequency questionnaire (FFQ). We assigned GI values to each item of the FFQ to estimate dietary GI and GL. Multivariate linear regression models were fitted to assess the association between GI/GL with CVD risk factors (blood glucose, total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides, apolipoprotein A1, body mass index, waist circumference and blood pressure). The potential modifying effect of sex, smoking status, diabetes and medication has been explored. RESULTS: A statistically significant inverse association between dietary GI and blood glucose was found in the multivariate model (p = 0.029): for every 10 unit increment of GI, serum glucose levels decreased by 0.2 units. However, statistical significance was lost after controlling for diabetes or hypoglycaemic medication. In the crude model, dietary GL was associated with triglycerides (ß for every 10 GL units increase = 0.70, p = 0.005), but statistical significance was lost in the multivariate model (p = 0.508). No associations were found between dietary GI/GL and the rest of the variables studied. CONCLUSIONS: Neither dietary GI nor GL were associated with CVD risk factors in the study population of Priego de Córdoba. Results obtained suggest the necessity to consider the diagnosis of diabetes in these studies.

Valoración de la ingesta de bebidas y del estado de hidratación / Assessment of beverage intake and hydration status

Está implicada en prácticamente la totalidad de sus funciones. Es especialmente importante en la termorregulación y en el rendimiento físico y cognitivo. El balance de agua refleja la ingesta y la pérdida de agua. La ingesta se realiza principalmente a través del consumo de agua potable y de bebidas (70 a 80%) más el agua que contienen los alimentos (20 a 30%). La pérdida de agua se realiza gracias a su excreción a través de la orina, las heces y el sudor. El interés por el tipo y la cantidad de bebidas consumidas no es nuevo, y se han utilizado numerosos enfoques para evaluarla, pero la validez de estos enfoques no se ha establecido correctamente. Aún no existe, en población general, un cuestionario estandarizado desarrollado como herramienta de investigación para la evaluación de la ingesta de agua. El uso de información de diferentes fuentes y diferentes características metodológicas plantea problemas de comparabilidad entre estudios. En Europa son escasos los estudios epidemiológicos actuales que se centran exclusivamente en el consumo de bebidas. Los biomarcadores de ingesta permiten evaluar objetivamente la ingesta dietética sin el sesgo producido por los errores del auto-reporte. Además, permiten superar el problema de la variabilidad intra-individual. Algunos métodos para medir ingesta alimentaria utilizan biomarcadores para validar los datos que recogen. Los marcadores biológicos ofrecen ventajas y son capaces de mejorar las estimaciones de la evaluación de ingesta dietética. Sin embargo, existen muy pocos estudios que examinen sistemáticamente la correlación entre la ingesta de bebidas y los biomarcadores de hidratación en diferentes poblaciones. Utilizando el cuestionario de bebidas de Hedrick y col. se realizó un estudio piloto para evaluar la validez y fiabilidad de un modelo multimedia interactivo (IMM) y para compararlo con una versión en papel auto-administrado (PP). El estudio mostró que el IMM parece ser un modelo válido y fiable para evaluar la ingesta habitual de bebidas. Un estudio similar se realizó en China, pero, en este caso, se empleó para evaluar la ingesta de bebidas la tecnología Smartphone. Conclusión: La metodología para valorar el consumo de bebidas en estudios poblacionales sigue siendo un tema controvertido. Existen pocos estudios validados y reproducibles, por lo que todavía no se dispone de un método ideal (corto, fácil de administrar, económico y preciso). Esta es un área de interés científico que aún está en desarrollo y que parece ser muy prometedora para mejorar las investigaciones en el área de la salud (AU)

Water is the main constituent of the human body. It is involved in practically all its functions. It is particularly important for thermoregulation and in the physical and cognitive performance. Water balance reflects water intake and loss. Intake of water is done mainly through consumption of drinking water and beverages (70 to 80%) plus water containing foods (20 to 30%). Water loss is mainly due to excretion of water in urine, faeces and sweat. The interest in the type and quantity of beverage consumption is not new, and numerous approaches have been used to assess beverage intake, but the validity of these approaches has not been well established. There is no standardized questionnaire developed as a research tool for the evaluation of water intake in the general population. Sometimes, the information comes from different sources or from different methodological characteristics which raises problems of the comparability. In the European Union, current epidemiological studies that focus exclusively on beverage intake are scarce. Biomarkers of intake are able to objectively assess dietary intake/status without the bias of self-reported dietary intake errors and also overcome the problem of intra-individual diet variability. Furthermore, some methods of measuring dietary intake used biomarkers to validate the data it collects. Biological markers may offer advantages and be able to improve the estimates of dietary intake assessment, which impact into the statistical power of the study. There is a surprising paucity of studies that systematically examine the correlation of beverages intake and hydration biomarker in different populations. A pilot investigation was developed to evaluate the comparative validity and reliability of newly developed interactive multimedia (IMM) versions compared to validated paper-administered (PP) versions of the Hedrick et al. beverage questionnaire. The study showed that the IMM appears to be a valid and reliable measure to assess habitual beverage intake. Similar study was developed in China, but in this case, the use of Smartphone technology was employed for beverage assessment. Conclusion: The methodology for measuring beverage intake in population studies remains controversial. There are few validated and reproducible studies, so there is still lacking an ideal method (ie, short, easy to administer, inexpensive and accurate) in this regard. Clearly, this is an area of scientific interest that is still in development and seems to be very promising for improving health research (AU)

Infradeclaración en las encuestas alimentarias: implicaciones metodológicas / Misreporting in nutritional surveys: methodological implications

La fiabilidad de la información recogida en la evaluación dietética puede verse afectada por diferentes factores. Una de las principales fuentes de error en la evaluación dietética es la declaración errónea de consumo de alimentos, que abarca la infradeclaración y sobre-declaración de la dieta. La infradeclaración de la ingesta de alimentos es uno de los principales problemas en la evaluación de la ingesta dietética habitual. Las características físicas y psicosociales que están relacionadas con la infradeclaración de energía incluyen el sexo, la edad, el peso, el índice de masa corporal, el miedo a la evaluación negativa y estar bajo un régimen de dieta, entre otros. En la actualidad, se emplean diversos métodos de referencia para verificar los resultados de la evaluación dietética, no obstante, el método estándar es el agua doblemente marcada. La infradeclaración afecta a la estimación de la ingesta de nutrientes y también altera las asociaciones entre dieta y enfermedades en estudios epidemiológicos. Por lo tanto, la infradeclaración tiene que ser considerada y abordada por los investigadores a través del desarrollo y mejora de los métodos de ajuste de la dieta y el aprovechamiento de las nuevas tecnologías para la evaluación de la ingesta dietética con el fin de minimizar el sesgo ocasionado por la infradeclaración (AU)

The reliability of the information collected in dietary assessment can be affected by different factors. One of the main sources of error in dietary assessment is misreporting which encompass under- and overreporting. Underreporting of food intake is one of the major problems in the assessment of habitual dietary intake. Physical and psychosocial characteristics that are related to energy underreporting include sex, age, weight, BMI, fear of negative evaluation and dieting among others. At present, diverse reference methods are employed to verify the results of dietary assessment and double labelled water is used as the gold standard method. Underreporting affects the estimation of nutrient intake and also alters associations between diet and disease assessed in epidemiological studies. Therefore, underreporting has to be considered and addressed by researchers through development and improvement of dietary intake adjustment methods, and taking advantage of the new technologies for assessing dietary intake in order to minimize underreporting bias (AU)

Effect of a Mediterranean Diet Intervention on Dietary Glycemic Load and Dietary Glycemic Index: The PREDIMED Study.

Objective. To compare the one year effect of two dietary interventions with MeDiet on GL and GI in the PREDIMED trial. Methods. Participants were older subjects at high risk for cardiovascular disease. This analysis included 2866 nondiabetic subjects. Diet was assessed with a validated 137-item food frequency questionnaire (FFQ). The GI of each FFQ item was assigned by a 5-step methodology using the International Tables of GI and GL Values. Generalized linear models were fitted to assess the relationship between the intervention group and dietary GL and GI at one year of follow-up, using control group as reference. Results. Multivariate-adjusted models showed an inverse association between GL and MeDiet + extra virgin olive oil (EVOO) group: ß = -8.52 (95% CI: -10.83 to -6.20) and MeDiet + Nuts group: ß = -10.34 (95% CI: -12.69 to -8.00), when comparing with control group. Regarding GI, ß = -0.93 (95% CI: -1.38 to -0.49) for MeDiet + EVOO, ß = -1.06 (95% CI: -1.51 to -0.62) for MeDiet + Nuts when comparing with control group. Conclusion. Dietary intervention with MeDiet supplemented with EVOO or nuts lowers dietary GL and GI.

A high dietary glycemic index increases total mortality in a Mediterranean population at high cardiovascular risk.

OBJECTIVE: Different types of carbohydrates have diverse glycemic response, thus glycemic index (GI) and glycemic load (GL) are used to assess this variation. The impact of dietary GI and GL in all-cause mortality is unknown. The objective of this study was to estimate the association between dietary GI and GL and risk of all-cause mortality in the PREDIMED study. MATERIAL AND METHODS: The PREDIMED study is a randomized nutritional intervention trial for primary cardiovascular prevention based on community-dwelling men and women at high risk of cardiovascular disease. Dietary information was collected at baseline and yearly using a validated 137-item food frequency questionnaire (FFQ). We assigned GI values of each item by a 5-step methodology, using the International Tables of GI and GL Values. Deaths were ascertained through contact with families and general practitioners, review of medical records and consultation of the National Death Index. Cox regression models were used to estimate multivariable-adjusted hazard ratios (HR) and their 95% CI for mortality, according to quartiles of energy-adjusted dietary GI/GL. To assess repeated measures of exposure, we updated GI and GL intakes from the yearly FFQs and used Cox models with time-dependent exposures. RESULTS: We followed 3,583 non-diabetic subjects (4.7 years of follow-up, 123 deaths). As compared to participants in the lowest quartile of baseline dietary GI, those in the highest quartile showed an increased risk of all-cause mortality [HR = 2.15 (95% CI: 1.15-4.04); P for trend  = 0.012]. In the repeated-measures analyses using as exposure the yearly updated information on GI, we observed a similar association. Dietary GL was associated with all-cause mortality only when subjects were younger than 75 years. CONCLUSIONS: High dietary GI was positively associated with all-cause mortality in elderly population at high cardiovascular risk.