On the interpretation of differences between groups for compositional data

Social polices are designed using information collected in surveys; such as the Catalan TimeUse survey. Accurate comparisons of time use data among population groups are commonlyanalysed using statistical methods. The total daily time expended on different activities by asingle person is equal to 24 hours. Because this type of data are compositional, its sample spacehas particular properties that statistical methods should respect. The critical points required tointerpret differences between groups are provided and described in terms of log-ratio methods.These techniques facilitate the interpretation of the relative differences detected in multivariateand univariate analysis

Log-ratio methods in mixture models for compositional data sets

When traditional methods are applied to compositional data misleading and incoherent results could be obtained. Finite mixtures of multivariate distributions are becoming increasingly important nowadays. In this paper, traditional strategies to fit a mixture model into compositional data sets are revisited and the major difficulties are detailed. A new proposal using a mixture of distributions defined on orthonormal log-ratio coordinates is introduced. A real data set analysis is presented to illustrate and compare the different methodologies

Aflojamiento séptico o aséptico de la prótesis total de cadera. Evaluación diagnóstica mediante gammagrafía con tecnecio, galio y leucocitos marcados con indio-111. Estudio comparativo

Resumen. Los autores han estudiado 28 pacientes portadores de prótesis total de cadera dolorosa en los que se sospechaba su infección. En todos los casos se efectuó una valoración clínico-radiológica, una gammagrafía con MDP-Tc 99m y Ga 67, usados secuencialmente, y después una gammagrafia con L-In 111. El diagnóstico de infección se basó en la clínica, la valoración quirúrgica, la anatomía patológica y los cultivos positivos. En 21 casos se descartó la infección. Las gammagrafies con Ga 67 y con L-ln 111 fueron normales en 19 ocasiones y patológicas en las dos restantes. La gammagrafía con MDP-Tc 99m fue normal en 15 casos y patológica en los seis restantes. En siete casos se demostró la infección periprotésica. La gammagrafía con L-ln 111 fue positiva en todos ellos, mientras que el Ga 67fue negativo en dos casos y el MDP-Tc 99m lo fue en tres casos. La sensibilidad, especificidad v flabilidad fueron, respectivamente: MDP-Tc 99m: 57,7, 71,4 v 67,8 por 100; Ga 67: 71,4, 90,4y 85,7por 100; L-ln 111: 100, 90,4y 92,8por 100. Los valores predictivos positivos y negativos para la exploración con leucocitos marcados alcanzaron cifras de 77,7 y 100 por 100, respectivamente, no superadas por el resto de pruebas. Los autores consideran que los resultados conseguidos confieren una superioridad a la gammagrafía con leucocitos marcados con ln-111-oxina sobre el resto de trazadores en el diagnostico diferencial entre aflojamiento séptico y aséptico de la prótesis total de cadera, y recomiendan su utilización tras la gammagrafía ósea convencion

The Conners Continuous Performance Test CPT3 ™ : Is it a reliable marker to predict neurocognitive dysfunction in Myalgic encephalomyelitis/chronic fatigue syndrome?

The main objective is to delimit the cognitive dysfunction associated with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) in adult patients by applying the Continuous Performance Test (CPT3 ™). Additionally, provide empirical evidence on the usefulness of this computerized neuropsychological test to assess ME/CFS. The final sample (n = 225; 158 Patients/67 Healthy controls) were recruited in a Central Sensitization Syndromes (CSS) specialized unit in a tertiary hospital. All participants were administered this neuropsychological test. There were significant differences between ME/CFS and healthy controls in all the main measures of CPT3 ™. Mainly, patients had a worse indicator of inattentiveness, sustained attention, vigilance, impulsivity, slow reaction time, and more atypical T-scores, which is associated with a likelihood of having a disorder characterized by attention deficits, such as Attention Deficit Hyperactivity Disorder (ADHD). In addition, relevant correlations were obtained between the CPT3 ™ variables in the patient's group. The most discriminative indicators of ME/CFS patients were Variability and Hit Reaction Time, both measures of response speed. The CPT3 ™ is a helpful tool to discriminate neurocognitive impairments from attention and response speed in ME/CFS patients, and it could be used as a marker of ME/CFS severity for diagnosing or monitoring this disease

Human development index, children's health-related quality of life and movement behaviors:a compositional data analysis

PURPOSE: Health-related quality of life has been related to physical activity, sedentary behavior, and sleep among children from developed nations. These relationships have rarely been assessed in developing nations, nor have behaviors been considered in their true context, as mutually exclusive and exhaustive parts of the movement behavior composition. This study aimed to explore whether children's health-related quality of life is related to their movement behavior composition and if the relationship differs according to human development index.METHODS: Children aged 9-11 years (n = 5855), from the 12-nation cross-sectional observational International Study of Childhood Obesity, Lifestyle and the Environment 2011-2013, self-reported their health-related quality of life (KIDSCREEN-10). Daily movement behaviors were from 24-h, 7-day accelerometry. Isometric log-ratio mixed-effect linear models were used to calculate estimates for difference in health-related quality of life for the reallocation of time between daily movement behaviors.RESULTS: Children from countries of higher human development index reported stronger positive relationships between health-related quality of life and moderate-to-vigorous physical activity, relative to the remaining behaviors (r = 0.75, p = 0.005) than those from lower human development index countries. In the very high human development index strata alone, health-related quality of life was significantly related to the movement behavior composition (p = 0.005), with moderate-to-vigorous physical activity (relative to remaining behaviors) being positively associated with health-related quality of life.CONCLUSIONS: The relationship between children's health-related quality of life and their movement behaviors is moderated by their country's human development index. This should be considered when 24-h movement behavior guidelines are developed for children around the world.</p

The Effect of Physical Activity and High Body Mass Index on Health-Related Quality of Life in Individuals with Metabolic Syndrome

[EN] The main objective of this study was to examine the relationship between the level of physical activity (PA) and the degree of obesity with health-related quality of life (HRQoL) in individuals with metabolic syndrome (MetS) who participated in the Predimed-Plus study. A total of 6875 subjects between 55 and 75 years of age with MetS were selected and randomized in 23 Spanish centers. Subjects were classified according to categories of body mass index (BMI). PA was measured with the validated Registre Gironi del Cor (REGICOR) questionnaire and subjects were classified according to their PA level (light, moderate, vigorous) and the HRQoL was measured with the validated short-form 36 (SF-36) questionnaire. By using the ANOVA model, we found a positive and statistically significant association between the level of PA and the HRQoL (aggregated physical and mental dimensions p < 0.001), but a negative association with higher BMI in aggregated physical dimensions p < 0.001. Furthermore, women obtained lower scores compared with men, more five points in all fields of SF-36. Therefore, it is essential to promote PA and body weight control from primary care consultations to improve HRQoL, paying special attention to the differences that sex incurs.SIThe Predimed-Plus trial was supported by the Spanish government’s official funding agency for biomedical research, ISCIII, through the Fondo de Investigación para la Salud (FIS), which is co-funded by the European Regional Development Fund (three coordinated FIS projects led by Jordi Salas-Salvadó and Josep Vidal, including the following projects: PI13/00673, PI13/00492, PI13/00272, PI13/01123, PI13/00462, PI13/00233, PI13/02184, PI13/00728, PI13/01090, PI13/01056, PI14/01722, PI14/0147, PI14/00636, PI14/00972, PI14/00618, PI14/00696, PI14/01206, PI14/01919, PI14/00853, PI14/01374, PI16/00473, PI16/00662, PI16/01873, PI16/01094, PI16/00501, PI16/00533, PI16/00381, PI16/00366, PI16/01522, PI16/01120, PI17/00764, PI17/01183, PI17/00855, PI17/01347, PI17/00525, PI17/01827, PI17/00532, PI17/00215, PI17/01441, PI17/00508, PI17/01732, PI17/00926, PI19/00957, PI19/00386, PI19/00309, PI19/01032, PI19/00576, PI19/00017, PI19/01226, PI19/00781, PI19/01560, PI19/01,332), the Special Action Project entitled: Implementación y evaluación de una intervención intensiva sobre la actividad física Cohorte PREDIMED-PLUS grant to Jordi Salas-Salvadó, the European Research Council (Advanced Research Grant 2013–2018; 340918) grant to Miguel Ángel Martínez-Gonzalez, the Recercaixa grant to Jordi Salas-Salvadó (2013ACUP00194), grants from the Consejería de Salud de la Junta de Andalucía (PI0458/2013; PS0358/2016; PI0137/2018), the PROMETEO/2017/017 grant from the Generalitat Valenciana, the SEMERGEN grant and FEDER funds (CB06/03 and CB12/03), Olga Castaner is funded by the JR17/00,022 grant, ISCIII. Christopher Papandreou is supported by a postdoctoral fellowship granted by the Autonomous Government of Catalonia (PERIS 2016–2020 Incorporació de Científics i Tecnòlegs, SLT002/0016/00,428). María Rosa Bernal-Lopez was supported by “Miguel Servet Type I” program (CP15/00028) from the ISCIII-Madrid (Spain), cofinanced by the Fondo Europeo de Desarrollo Regional-FEDER, Ignacio M.Giménez-Alba is supported by a FPU predoctoral contract (reference FPU18/01703) from the Ministerio de Ciencia, Innovación y Universidades, Spain

Dietary diversity and Depression: Cross-sectional and longitudinal analyses in Spanish adult population with Metabolic Syndrome. Findings from PREDIMED-PLUS Trial.

Objective: To examine the cross-sectional and longitudinal (2-year follow-up) associations between Dietary Diversity (DD) and depressive symptoms. Design: An energy-adjusted Dietary Diversity Score (DDS) was assessed using a validated food-frequency questionnaire and was categorized into quartiles (Q). The variety in each food group was classified into 4 categories of diversity (C). Depressive symptoms were assessed with Beck Depression Inventory-II (Beck II) questionnaire and depression cases defined as physician-diagnosed or Beck II>=18. Linear and logistic regression models were used. Setting: Spanish older adults with Metabolic Syndrome. Participants: A total of 6625 adults aged (55-75 years) from the PREDIMED-Plus study with overweight or obesity and MetS. Results: Total DDS was inversely and statistically significantly associated with depression in the cross-sectional analysis conducted; Odds Ratio (OR) Q4 vs Q1= 0.76 (95% confidence interval (CI): 0.64, 0.90). This was driven by high diversity compared to low diversity (C3 vs. C1) of vegetables [OR (95%CI) = 0.75 (0.57, 0.93)], cereals [OR (95%CI) = 0.72 (0.56-0.94)] and proteins [OR (95%CI) = 0.27 (0.11, 0.62)]. In the longitudinal analysis, there was no significant association between the baseline DDS and changes in depressive symptoms after 2 y- of follow-up, except for DD in vegetables C4 vs C1= [β (95%CI) = 0.70 (0.05, 1.35)]. Conclusions: According to our results, DD is associated with the presence of depressive symptoms but eating more diverse does not seem to reduce the risk of future depression. Additional longitudinal studies (with longer follow-up period) are needed to confirm these findings

Effect of a nutritional intervention based on an energy-reduced Mediterranean diet on environmental impact

[EN]To estimate the environmental impact of a dietary intervention based on an energy-reduced Mediterranean diet (MedDiet) after one year of follow-up. Methods Baseline and 1-year follow-up data were used for 5800 participants aged 55–75 years with metabolic syndrome in the PREDIMED-Plus study. Food intake was estimated through a validated semiquantitative food consumption frequency questionnaire, and adherence to the MedDiet was estimated through the Diet Score. Using the EAT-Lancet Commission tables we assessed the influence of dietary intake on environmental impact (through five indicators: greenhouse gas emissions (GHG), land use, energy used, acidification and potential eutrophication). Using multivariable linear regression models, the association between the intervention and changes in each of the environmental factors was assessed. Mediation analyses were carried out to estimate to what extent changes in each of 2 components of the intervention, namely adherence to the MedDiet and caloric reduction, were responsible for the observed reductions in environmental impact. Results We observed a significant reduction in the intervention group compared to the control group in acidification levels (−13.3 vs. -9.9 g SO2-eq), eutrophication (−5.4 vs. -4.0 g PO4-eq) and land use (−2.7 vs. -1.8 m2). Adherence to the MedDiet partially mediated the association between intervention and reduction of acidification by 15 %, eutrophication by 10 % and land use by 10 %. Caloric reduction partially mediated the association with the same factors by 55 %, 51 % and 38 % respectively. In addition, adherence to the MedDiet fully mediated the association between intervention and reduction in GHG emissions by 56 % and energy use by 53 %.SIPublicación en abierto financiada por el Consorcio de Bibliotecas Universitarias de Castilla y León (BUCLE), con cargo al Programa Operativo 2014ES16RFOP009 FEDER 2014-2020 DE CASTILLA Y LEÓN, Actuación:20007-CL - Apoyo Consorcio BUCL

Dietary diversity and nutritional adequacy among an older Spanish population with metabolic syndrome in the PREDIMED-Plus study: a cross-sectional analysis

Dietary guidelines emphasize the importance of a varied diet to provide an adequate nutrient intake. However, an older age is often associated with consumption of monotonous diets that can be nutritionally inadequate, increasing the risk for the development or progression of diet-related chronic diseases, such as metabolic syndrome (MetS). To assess the association between dietary diversity (DD) and nutrient intake adequacy and to identify demographic variables associated with DD, we cross-sectionally analyzed baseline data from the PREDIMED-Plus trial: 6587 Spanish adults aged 55-75 years, with overweight/obesity who also had MetS. An energy-adjusted dietary diversity score (DDS) was calculated using a 143-item validated semi-quantitative food frequency questionnaire (FFQ). Nutrient inadequacy was defined as an intake below 2/3 of the dietary reference intake (DRI) forat least four of 17 nutrients proposed by the Institute of Medicine (IOM). Logistic regression models were used to evaluate the association between DDS and the risk of nutritionally inadequate intakes. In the higher DDS quartile there were more women and less current smokers. Compared with subjects in the highest DDS quartile, those in the lowest DDS quartile had a higher risk of inadequate nutrient intake: odds ratio (OR) = 28.56 (95% confidence interval (CI) 20.80-39.21). When we estimated food varietyfor each of the food groups, participants in the lowest quartile had a higher risk of inadequate nutrient intake for the groups of vegetables, OR = 14.03 (95% CI 10.55-18.65), fruits OR = 11.62 (95% CI 6.81-19.81), dairy products OR = 6.54 (95% CI 4.64-9.22) and protein foods OR = 6.60 (95% CI 1.96-22.24). As DDS decreased, the risk of inadequate nutrients intake rose. Given the impact of nutrient intake adequacy on the prevention of non-communicable diseases, health policies should focus on the promotion of a healthy varied diet, specifically promoting the intake of vegetables and fruit among population groups with lower DDS such as men, smokers or widow(er)s