Effects of diet and exercise on metabolic syndrome and the underlying factors = Efectos de la dieta y el ejercicio sobre el síndrome metabólico y sus factores

Introducción. El número de personas que padecen síndrome metabólico ha incrementado a nivel mundial durante las últimas dos décadas. Existen numerosos estudios que tratan de comparar prevalencias según los diferentes criterios y estimaciones del riesgo metabólico. De ellos se puede concluir que el principal hallazgo ha sido recalcar la necesidad de una definición estándar universal. A pesar de estas discrepancias no hay lugar a duda sobre el problema de salud pública que esto conlleva. Se necesitan medidas y estrategias urgentes para prevenir y controlar esta emergente epidemia global y para ello se debe prestar especial atención a los cambios en el estilo de vida, fundamentalmente dieta y ejercicio. A pesar de todo, existe a día de hoy una importante controversia sobre el tipo de ejercicio más efectivo y su combinación con la dieta para conseguir mejoras en la salud. Objetivos. Estudiar los índices de riesgo metabólico empleados en la literatura científica y las terapias basadas en dieta y ejercicio para el tratamiento de los factores del síndrome metabólico en adultos con sobrepeso. Diseño de investigación. Los datos empleados en el análisis de esta tesis son, primeramente un estudio piloto, y posteriormente parte del estudio “Programas de Nutrición y Actividad Física para el tratamiento de la obesidad” (PRONAF). El estudio PRONAF es un proyecto consistente en un estudio clínico sobre programas de nutrición y actividad física para el sobrepeso y la obesidad, desarrollado en España durante varios años de intervenciones. Fue diseñado, en parte, para tratar de comparar protocolos de entrenamiento de resistencia, cargas y combinado en igualdad de volumen e intensidad, con el objetivo de evaluar su impacto en los factores de riesgo y la prevalencia del síndrome metabólico en personas con sobrepeso y obesidad. El diseño experimental es un control aleatorio y el protocolo incluye 3 modos de ejercicio (entrenamiento de resistencia, con cargas y combinado) y restricción dietética sobre diversas variables determinantes del estado de salud. Las principales variables para la investigación que comprende esta tesis fueron: actividad física habitual, marcadores de grasa corporal, niveles de insulina, glucosa, triglicéridos, colesterol total, colesterol HDL, colesterol LDL, presión arterial y parámetros relacionados con el ejercicio. Conclusiones. A) Los índices de riesgo metabólico estudiados presentan resultados contradictorios en relación al riesgo metabólico en un individuo, dependiendo de los métodos matemáticos empleados para el cálculo y de las variables introducidas, tanto en mujeres sanas como en adultos en sobrepeso. B) El protocolo de entrenamiento combinado (de cargas y de resistencia) junto con la dieta equilibrada propuesto en este estudio fue la mejor estrategia para la mejora del riesgo de síndrome metabólico en adultos con sobrepeso. C) Los protocolos de entrenamiento supervisado de resistencia, con cargas y combinado junto con la restricción nutricional, no obtuvieron mejoras sobre el perfil lipídico, más allá de los cambios conseguidos con el protocolo de dieta y recomendaciones generales de actividad física habitual en clínica, en adultos con sobrepeso. Background. Over the past two decades, a striking increase in the number of people with the MetS worldwide has taken place. Many studies compare prevalences using different criteria and metabolic risk estimation formulas, and perhaps their main achievement is to reinforce the need for a standardized international definition. Although these discrepancies, there is no doubt it is a public health problem. There is urgent need for strategies to prevent and manage the emerging global epidemic, special consideration should be given to behavioral and lifestyle, mainly diet and exercise. However, there is still controversy about the most effective type of exercise and diet combination to achieve improvements. Objectives. To study the metabolic risk scores used in the literature and the diet and exercise therapies for the treatment of the MetS factors in overweight adults. Research design. The data used in the analysis was collected firstly in a pilot study and lately, as a part of the “Programas de Nutrición y Actividad física para el tratamiento de la obesidad” study (PRONAF). The PRONAF Study is a clinical research project in nutrition and physical activity programs for overweight and obesity, carried out in Spain (2008-2011). Was designed, in part, to attempt to match the volume and intensity of endurance, strength and combined training protocols in order to evaluate their impact on risk factors and MetS prevalence in overweight and obese people. The design and protocol included three exercise modes (endurance, strength and combined training) and diet restriction, in a randomized controlled trial concerning diverse health status variables. The main variables under investigation were habitual physical activity, markers of body fat, fasting serum levels of insulin, glucose, triglycerides, total, LDL and HDL cholesterol, blood pressure and diet and exercise parameters. Main outcomes. A) The metabolic risk scores studied presented contradictory results in relation to the metabolic risk of an individual, depending on the mathematical method used and the variables included, both in healthy women and overweight adults. B) The protocol proposed for combination of strength and endurance training combined with a balance diet was the optimal strategy for the improvement of MetS risk in overweight adults. C) The intervention program of endurance, strength or combined supervised training protocol with diet restriction did not achieved further improvements in lipid profile than a habitual clinical practice protocol including dietary advice and standard physical activity recommendations, in overweight adults.

Myocardial and vascular dysfunction and exercise capacity in the metabolic syndrome

The metabolic syndrome (MS) is associated with cardiovascular risk exceeding that expected from atherosclerotic risk factors, but the mechanism of this association is unclear. We sought to determine the effects of the MS on myocardial and vascular function and cardiorespiratory fitness in 393 subjects with significant risk factors but no cardiovascular disease and negative stress echocardiographic findings. Myocardial function was assessed by global strain rate, strain, and regional systolic velocity (s(m)) and diastolic velocity (e(m)) using tissue Doppler imaging. Arterial compliance was assessed using the pulse pressure method, involving simultaneous radial applanation tonometry and echocardiographic measurement of stroke volume. Exercise capacity was measured by expired gas analysis. Significant and incremental variations in left ventricular systolic (s(m), global strain, and strain rate) and diastolic (e(m)) function were found according to the number of components of MS (p <0.001). MS contributed to reduced systolic and diastolic function even in those without left ventricular hypertrophy (p <0.01). A similar dose-response association was present between the number of components of the MS and exercise capacity (p <0.001) and arterial compliance. The global strain rate and em were independent predictors of exercise capacity. In conclusion, subclinical left ventricular dysfunction corresponded to the degree of metabolic burden, and these myocardial changes were associated with reduced cardiorespiratory fitness.' Subjects with MS who also have subclinical myocardial abnormalities and reduced cardiorespiratory fitness may have a higher risk of cardiovascular disease events and heart failure. (C) 2005 Elsevier Inc. All rights reserved.

Fat as an endocrine organ: Relationship to the metabolic syndrome

Obesity and the metabolic syndrome have both reached pandemic proportions. Together they have the potential to impact on the incidence and severity of cardiovascular pathologies, with grave implications for worldwide health care systems. The metabolic syndrome is characterized by visceral obesity, insulin resistance, hypertension, chronic inflammation, and thrombotic disorders contributing to endothelial dysfunction and, subsequently, to accelerated atherosclerosis. Obesity is a key component in development of the metabolic syndrome and it is becoming increasingly clear that a central factor in this is the production by adipose cells of bioactive substances that directly influence insulin sensitivity and vascular injury. In this paper, we review advances in the understanding of biologically active molecules collectively referred to as adipokines and how dysregulated production of these factors in obese states mediates the pathogenesis of obesity associated metabolic syndrome.

Butyrylcholinesterase: Association with the metabolic syndrome and identification of 2 gene loci affecting activity

Background: Plasma cholinesterase activity is known to be correlated with plasma triglycerides, HDL- and LDL-cholesterol, and other features of the metabolic syndrome. A role in triglyceride metabolism has been proposed. Genetic variants that decrease activity have been studied extensively, but the factors contributing to overall variation in the population are poorly understood. We studied plasma cholinesterase activity in a sample of 2200 adult twins to assess covariation with cardiovascular risk factors and components of the metabolic syndrome, to determine the degree of genetic effects on enzyme activity, and to search for quantitative trait loci affecting activity. Methods and Results: Cholinesterase activity was lower in women than in men before the age of 50, but increased to activity values similar to those in males after that age. There were highly significant correlations with variables associated with the metabolic syndrome: plasma triglyceride, HDL- and LDL-cholesterol, apolipoprotein B and E, urate, and insulin concentrations; gamma-glutamyltransferase and aspartate and alanine aminotransferase activities; body mass index; and blood pressure. The heritability of plasma cholinesterase activity was 65%. Linkage analysis with data from the dizygotic twin pairs showed suggestive linkage on chromosome 3 at the location of the cholinesterase WHO gene and also on chromosome 5. Conclusions: Our results confirm and extend the connection between cholinesterase, cardiovascular risk factors, and metabolic syndrome. They establish a substantial heritability for plasma cholinesterase activity that might be attributable to variation near the structural gene and at an independent locus. (c) 2006 American Association for Clinical Chemistry.

Dietary patterns and metabolic syndrome - a review of epidemiologic evidence

Metabolic syndrome is associated with increased risk of coronary heart disease and type 2 diabetes, and appears to be widely prevalent in both developed and developing countries. While lifestyle modification is recommended for management of the syndrome, the dietary pattern most beneficial for patients is yet to be ascertained. Original research papers from the Medline database were examined for dietary patterns that may be associated with the syndrome. Three large-scale epidemiological studies were found fitting our criteria. Dietary patterns high in fruit and vegetable content were generally found to be associated with lower prevalence of metabolic syndrome. Diet patterns with high meat intake were frequently associated with components of metabolic syndrome, particularly impaired glucose tolerance. High dairy intake was generally associated with reduced risk for components of metabolic syndrome with some inconsistency in the literature regarding risk of obesity. Minimally processed cereals appeared to be associated with decreased risk of metabolic syndrome, while highly processed cereals with high glycaemic index are associated with higher risk. Fried foods were noticeably absent from any dietary pattern associated with decreased prevalence of metabolic syndrome. The conclusion of this review is that no individual dietary component could be considered wholly responsible for the association of diet with metabolic syndrome. Rather it is the overall quality of the diet that appears to offer protection against lifestyle disease such as metabolic syndrome. Further research is required into conditions, such as overweight and obesity, which may influence the effect of diet on the development of metabolic syndrome.