Prevalence and costs of malnutrition in hospitalized patients; the PREDyCES Study.

BACKGROUND AND AIMS: The main objective of the PREDyCES study was twofold. First, to analyse the prevalence of hospital malnutrition in Spain, both at admission and at discharge, and second, to estimate the hospital costs associated with disease-related malnutrition. METHODS: The study was a nationwide, cross-sectional, observational, multicentre study in routine clinical practice, which assessed the prevalence of hospital malnutrition both at patient admission and discharge using NRS-2002. A study extension analysed the incidence of complications associated with malnutrition, excess hospital stay and healthcare costs associated with hospital malnutrition. RESULTS: Malnutrition was observed in 23.7% of patients according to NRS-2002. Multivariate analysis revealed that age, gender, presence of malignant disease, diabetes mellitus, dysphagia and polymedication were the main factors associated with the presence of malnutrition. Malnutrition was associated with an increase in length of hospital stay, especially in patients admitted without malnutrition but who presented malnutrition at discharge (15.2 vs. 8.0 days, p < 0.001), with an associated additional cost of €5,829 per patient. CONCLUSION: In Spanish hospitals, almost one in four patients is malnourished. This condition is associated with increased length of hospital stay and associated costs, especially in patients developing malnutrition during hospitalization. Systematic screening for malnutrition should be generalised in order to implement nutritional interventions with well-known effectiveness.

Prevalence and costs of malnutrition in hospitalized patients; the PREDyCES® Study / Prevalencia y costes de la malnutrición en pacientes hospitalizados; estudio PREDyCES®

Background and aims: The main objective of the PREDyCES® study was twofold. First, to analyse the prevalence of hospital malnutrition in Spain, both at admission and at discharge, and second, to estimate the hospital costs associated with disease-related malnutrition. Methods: The study was a nationwide, cross-sectional, observational, multicentre study in routine clinical practice, which assessed the prevalence of hospital malnutrition both at patient admission and discharge using NRS-2002®. A study extension analysed the incidence of complications associated with malnutrition, excess hospital stay and healthcare costs associated with hospital malnutrition. Results: Malnutrition was observed in 23.7% of patients according to NRS-2002®. Multivariate analysis revealed that age, gender, presence of malignant disease, diabetes mellitus, dysphagia and polymedication were the main factors associated with the presence of malnutrition. Malnutrition was associated with an increase in length of hospital stay, especially in patients admitted without malnutrition but who presented malnutrition at discharge (15.2 vs. 8.0 days, p < 0.001), with an associated additional cost of €5,829 per patient. Conclusion: In Spanish hospitals, almost one in four patients is malnourished. This condition is associated with increased length of hospital stay and associated costs, especially in patients developing malnutrition during hospitalization. Systematic screening for malnutrition should be generalised in order to implement nutritional interventions with well-known effectiveness (AU)

Justificación y objetivos: El estudio PREDyCES® tuvo dos objetivos principales. Primero, analizar la prevalencia de desnutrición hospitalaria (DH) en España tanto al ingreso como al alta, y segundo, estimar sus costes asociados. Métodos: Estudio nacional, transversal, observacional, multicéntrico, en condiciones de práctica clínica habitual que evaluó la presencia de desnutrición hospitalaria al ingreso y al alta mediante el NRS-2002®. Una extensión del estudio analizó la incidencia de complicaciones asociadas a la desnutrición, el exceso de estancia hospitalaria y los costes sanitarios asociados a la DH. Resultados: La prevalencia de desnutrición observada según el NRS-2002® fue del 23.7%. El análisis multivariante mostró que la edad, el género, la presencia de enfermedad oncológica, diabetes mellitus, disfagia y la polimedicación fueron los factores principales que se asociaron a la presencia de desnutrición. La DH se asoció a un incremento de la estancia hospitalaria, especialmente en aquellos pacientes que ingresaron sin desnutrición y que presentaron desnutrición al alta (15.2 vs 8.0 días; p < 0.001), con un coste adicional asociado de 5.829€ por paciente. Conclusiones: Uno de cada cuatro pacientes en los hospitales españoles se encuentra desnutrido. Esta condición se asocia a un exceso de estancia hospitalaria y costes asociados, especialmente en pacientes que se desnutren durante su hospitalización. Se debería generalizar el cribado nutricional sistemático con el objetivo de implementar intervenciones nutricionales de conocida eficacia (AU)

The burden of hospital malnutrition in Spain: methods and development of the PREDyCES® study / El coste de la desnutrición hospitalaria en España: método y desarrollo del estudio PREDyCES®

It is well known that hospital malnutrition is ahighly prevalent condition associated to increase morbidity and mortality as well as related healthcarecosts. Although previous studies have already measured the prevalence and/or costs of hospital nutrition in our country, their local focus (at regionalor even hospital level) make that the true prevalence and economic impact of hospital malnutrition for the National Health System remain unknown inSpain. The PREDyCES® (Prevalence of hospitalmal nutrition and associated costs in Spain) study was aimed to assess the prevalence of hospital malnutrition in Spain and to estimate related costs.Some aspects made this study unique: a) It was the first study in a representative sample of hospitals ofSpain; b) different measures to assess hospital malnutrition (NRS2002, MNA as well as anthropometric and biochemical markers) where used both at admission and discharge and, c) the economic consequences of malnutrition where estimated using the perspective of the Spanish National Health System (AU)

Es bien sabido que la desnutrición hospitalaria es un proceso altamente prevalente asociado al aumento de la morbilidad y mortalidad, así como a elevados costes sanitarios. Aunque estudios previos han medido la prevalencia y/o los costes de la nutrición hospitalaria en nuestro país, su enfoque local(regional o incluso a nivel hospitalario) hacen que la verdadera prevalencia e impacto económico de la desnutrición hospitalaria para el Sistema Nacional de Salud sean aún desconocidos en España. El objetivo del estudio PREDyCES®(Prevalencia de la Desnutrición hospitalaria y los Costes asociados en ESpaña) fue evaluar la prevalencia de la desnutrición hospitalaria en España y estimar sus costes asociados.Algunos aspectos de este estudio lo hicieron singular: a) Fue el primer estudio de este tipo con una muestra representativa de los hospitales de España, b) se utilizaron diferente medidas para evaluar la desnutrición hospitalaria (NRS 2002,MNA, así como marcadores antropométricos y bioquímicos)tanto en el momento del ingreso como al alta hospitalaria y, c)se estimaron las consecuencias económicas de la desnutrición desde la perspectiva del Sistema Nacional de Salud español (AU)

The burden of hospital malnutrition in Spain: methods and development of the PREDyCES® study.

It is well known that hospital malnutrition is a highly prevalent condition associated to increase morbidity and mortality as well as related healthcare costs. Although previous studies have already measured the prevalence and/or costs of hospital nutrition in our country, their local focus (at regional or even hospital level) make that the true prevalence and economic impact of hospital malnutrition for the National Health System remain unknown in Spain. The PREDyCES® (Prevalence of hospital malnutrition and associated costs in Spain) study was aimed to assess the prevalence of hospital malnutrition in Spain and to estimate related costs. Some aspects made this study unique: a) It was the first study in a representative sample of hospitals of Spain; b) different measures to assess hospital malnutrition (NRS2002, MNA as well as anthropometric and biochemical markers) where used both at admission and discharge and, c) the economic consequences of malnutrition where estimated using the perspective of the Spanish National Health System.

Dietary calcium and body mass index in a Mediterranean population.

This cross-sectional study evaluated the association between daily calcium intake and body mass index (BMI) in 647 subjects from Reus, Spain. 261 men and 313 women, aged 18 to 70 years, were randomly selected from the population census. Food intake was quantified by the 24-hour recall method, for three non-consecutive days including one holiday. Weight and height were measured. The study sample was divided into quartiles of calcium intake adjusted for age, energy, and total fat and fiber intake in both men and women. Average calcium intake was low (557.6 +/- 234.0 mg/day). Calcium intake was significantly (p < 0.0001) and positively associated with energy intake (r = 0.50 for men; r = 0.49 for women; p < 0.0001) and dietary fiber consumption (r = 0.27 for men; r = 0.25 for women; p < 0.0001). After adjusting for age, energy intake, fat intake, and dietary fiber, the odds ratio of being in the highest quartile of BMI was significantly reduced in the highest quartile of calcium intake [men: 0.63 (0.30-1.29); women: 0.36 (0.17-0.79)] compared to the lowest quartile in both sexes. We conclude that our study showed a negative relationship between calcium intake and BMI in a Mediterranean community.

Subcutaneous adipose tissue cytokine production is not responsible for the restoration of systemic inflammation markers during weight loss.

CONTEXT: It has been suggested that weight loss can improve systemic inflammation associated with obesity by decreasing the adipose production of pro-inflammatory cytokines. This suggestion, however, remains controversial. OBJECTIVE: To analyse the effect of weight loss on peripheral inflammatory markers and subcutaneous adipocytokine production. DESIGN: Patients were studied at baseline, at the end of the weight loss period, and after 2 weeks of weight stabilisation. SUBJECTS: Nineteen morbid obese non-diabetic patients and 20 lean control subjects. INTERVENTION: During the weight loss period patients followed a 6-week low-calorie diet. MEASUREMENTS: Plasma levels of inflammatory markers, maximal in vitro whole-blood cytokine production, subcutaneous adipose tissue expression and content of several cytokines. RESULTS: Obese subjects had higher circulating levels of C reactive protein (CRP), serum amyloid A (SAA), interleukin IL-6, IL-1 and soluble tumor necrosis factor receptors (sTNFR). Weight loss was associated with a significant decrease in CRP, SAA, leucocytes and plasma IL-6. Maximal in vitro cytokine production of IL-1 and sTNFR1 increased during this period. Weight loss did not induce significant changes in the adipose concentrations of IL-6, IL-1 or sTNF-receptors. However, adipose expression of IL-6, IL-1, TNFalpha, membrane cofactor protein-1 and adiponectin increased at the end of the weight loss period. During weight maintenance, circulating inflammatory parameters increased and in some cases returned to baseline. CONCLUSIONS: A low-calorie diet is associated with an improvement in the systemic inflammatory status. This seems to be due to energy restriction rather than to adipose mass loss, since inflammatory levels return to baseline soon after weight stabilisation. Furthermore, a negative energy balance and fat mobilisation are associated with increased subcutaneous cytokine adipose expression.

C-reactive protein, adiposity and cardiovascular risk factors in a Mediterranean population.

BACKGROUND: Understanding the distribution of high-sensitivity C-reactive protein (CRP) and its relations with classic cardiovascular risk factors in specific populations is important for further diagnostic use. METHODS: We studied 1,157 adult subjects (652 women and 505 men) participating in the Health Study of Catalonia. CRP concentrations were measured with a high-sensitivity turbidimetric assay. RESULTS: Median levels of CRP were 1.57 mg/l and 25% of both men and women had CRP values >3 mg/l. No differences were observed between men and women even after adjustment for age and body mass index (BMI). After patients with CRP values above the 97.5th percentile (n = 31) had been excluded, CRP concentrations increased significantly with increasing levels of cardiovascular risk factors in both men and women. Men and women with metabolic syndrome showed significantly higher levels of CRP than their counterparts, even after adjustment for BMI and age. In a multiple regression analysis, BMI, triglycerides and fasting glucose were independent predictors of CRP in women and together explained 42% of its variance. In men, CRP was independently and positively associated to waist circumference, smoking, diastolic blood pressure, uric acid and triglycerides, and negatively associated to HDL-cholesterol. Altogether these variables explained 51% of its variability. CONCLUSIONS: The present study describes, for the first time, CRP concentrations in a sample that is representative of a Spanish Mediterranean community. CRP distribution and correlates are very similar to those reported previously in spite of the different lifestyle and nutritional habits, and the lower rates of cardiovascular diseases in our population.

[Nutrient content and health effects of nuts]. / Composición nutritiva y efectos sobre la salud de los frutos secos.

Nuts are foods with a high energy density, due in part to its small water content. They also present a low saturated fat content (<7%) but a high unsaturated fat contribution (40-60%). They represent one of the richest sources of dietary fiber, which is basically of the insoluble type. The effects of nut intake on health have been widely studied. Several prospective epidemiological studies performed on large cohorts have consistently shown that regular consumption of small amounts of nuts is negatively related to the risk of cardiovascular disease and to the risk of cardiovascular or all-cause mortality. From these studies can be concluded that regular consumption of small amounts of nuts leads to a 30-50% reduction in the risk of cardiovascular disease. Additionally, intervention studies have shown a positive effect of nut intake on lipid profile with significant reductions in total and LDL cholesterol levels and small or null effects on the HDL fraction. More recently, some studies have focused on the effect of nuts on body weight. At present, no evidences support a detrimental effect of nut consumption on body weight. On the contrary some weight loss studies suggest a beneficial effect of nut intake on body weight regulation.

Composición nutritiva y efectos sobre la salud de los frutos secos / Nutrient content and health effects of nuts

Los frutos secos son alimentos caracterizados por una alta densidad energética debida en parte a su escaso contenido hídrico. Además, presentan un bajo contenido en grasa saturada (<7 por ciento) y un elevado aporte de grasa insaturada (40-60 por ciento). Constituyen también una de las fuentes más ricas de fibra dietética, fundamentalmente insoluble. Se ha estudiado ampliamente cuales son los efectos que la ingestión de frutos secos tiene sobre la salud. Diversos estudios epidemiológicos prospectivos realizados sobre amplias cohortes han mostrado consistentemente una relación negativa entre el consumo regular de pequeñas cantidades de frutos secos y el riesgo de enfermedad cardiovascular o el riesgo de mortalidad de origen cardiovascular y de mortalidad por todas las causas. El análisis de estos estudios refleja que el consumo regular de pequeñas cantidades de frutos secos reduce el riesgo de enfermedad cardiovascular en un 30-50 por ciento. Los estudios de intervención demuestran que la toma regular de suplementos de frutos secos mejora el perfil lipídico, reduciendo significativamente los niveles de colesterol total y colesterol LDL con escaso o nulo efecto sobre las HDL. El efecto de los frutos secos sobre el peso corporal ha sido también recientemente estudiado. Hasta el momento no existen evidencias de un aumento de peso corporal asociado al consumo de estos alimentos y, sin embargo, algunos estudios de pérdida ponderal sugieren un posible efecto beneficioso en la regulación del peso corporal

Nut consumption, body weight and insulin resistance.

The beneficial effects of nuts on cardiovascular health are well known. However, since nuts provide a high caloric and fat content, some concern exists regarding a potential detrimental effect on body weight and insulin resistance. The current data available did not support such a negative effect of nut consumption on the short term or when nuts are included on diets that meet energy needs. Furthermore, there is some intriguing evidence that nuts can help to regulate body weight and protect against type II diabetes. This, however, still has to be proved and more research is needed to address the specific effects of nuts on satiety, energy balance, body weight and insulin resistance.

Potential uses and benefits of phytosterols in diet: present situation and future directions.

Over the past decade, the possibility of using phytosterols as ingredients in functional foods has led to numerous research studies in relation to their ability to reduce blood cholesterol. Many different types of carriers have been tested, with good results. The main conclusion is that the effective doses were between 1.5 and 3g/day, leading to reductions between 8% and 15% in LDL-cholesterol. The principal mechanism of action is based on interference with the solubilisation of the cholesterol in the intestinal micelles and, thus, absorption is reduced. Work has also been done on the optimal pattern of administration, and it has been found that ingesting phytosterols in a single dose per day or between meals are equally effective methods. The only side effect is that they can interfere with the absorption of carotenoids, but this can be compensated for in the diet or by adding these compounds in appropriate carriers. It has also been reported that phytosterols have anticancer properties and act as immune system modulators. There are several possible future lines of research: alternative sources with a high phytosterol content must be found, industrial processes must be implemented which minimise their loss, phytosterols must be included in food composition tables, the potential of the different types of phytosterols must be discerned, the genetic bases of their action must be elucidated, synergic effects with other compounds must be studied, side effects must be minimised, and the effects of long-term treatment must be defined precisely.

[The teaching of nutrition at medical schools:current situation]. / La enseñanza de la nutrición en las facultades de Medicina: situación actual.

BACKGROUND: Although doctors, students and teachers all coincide in acknowledging the need for an appropriate knowledge of human nutrition in order to practice medicine, the inclusion of this discipline in the undergraduate curriculum has been rather scant. Until a few years ago, there were only two medical schools in Spain with a compulsory course in nutrition as part of the syllabus. GOAL: An attempt will be made to assess the current status of the teaching of nutrition within the syllabuses for a degree in Medicine and Surgery at Spanish universities. MATERIALS: The syllabuses of 27 Faculties of Medicine in Spain have been consulted to find out: 1) if there are specific subjects on nutrition, feeding and/or dietetics, 2) if these subjects are compulsory or optional, and 3) if there are specific issues from this area included within other subjects. RESULTS: The results of the query show that 7 schools (approximately 25% of the total) teach a compulsory subject on nutrition or dietetics whereas 17 have at least one optional subject in this field, particularly during the second or specialization stage, with a mean content worth 4.5 credits. Furthermore, 3 of the schools offer both compulsory and optional courses simultaneously. Within the course material of the core subjects included in the second stage of the degree, the subjects of Endocrinology, Metabolism and Paediatrics seem to be the ones most commonly including clinical nutrition topics, generally with a very small relative weight. CONCLUSIONS: The results obtained show an increasing interest in the creation of distinctive subjects for nutrition and/or dietetics. Nonetheless, this is still mainly an optional subject and the integration of human nutrition into the syllabus for core subjects seems insufficient for its to be considered a good alternative.

Intralipid/heparin infusion suppresses serum leptin in humans.

BACKGROUND/AIM: Our previous studies showed that administration of dexamethasone plus food increased serum leptin levels 100% more than dexamethasone alone. We hypothesized that this increase in leptin from the meal could result directly from the provision of fuel metabolites rather than from the meal-induced rise in insulin. In the current study, we tested the effect of an i.v. lipid fuel source (Intralipid 20%/heparin) that would incur only a modest increase in insulin. This study was undertaken because the role of lipid in the regulation of human leptin levels has been controversial, with differing effects reported: stimulatory, inhibitory, or no effect at all. METHODS: In order to evaluate how lipids affect serum leptin in humans, we administered the following to seven lean, healthy, fasting subjects: (i) Intralipid 20% at 0.83 ml/kg.h plus heparin (800 IE/h) infused i.v. for 7 h (LIPID), (ii) LIPID with one initial pulse of insulin (0.09 U/kg) given s.c. (LIPID+INS), (iii) LIPID with dexamethasone (2 mg i.v. push) given at the start of the infusion (LIPID+DEX), and (iv) LIPID with insulin plus dexamethasone (LIPID+INS+DEX). Control trials in another 14 subjects matched hormonal conditions but lacked the LIPID infusion. Blood levels were collected over 8 h for determination of free fatty acids (FFA), glucose, insulin, and leptin under each experimental condition. RESULTS: Over the 420 min of LIPID infusion, FFA levels rose four-fold from 0.28+/-0.05 mmol/l to 0.99+/-0.05 mmol/l. Serum leptin levels were suppressed by 10-20% in the LIPID condition as compared with control (no LIPID) between 90 min (P=0.008) and 360 min (P=0.045). LIPID+DEX did not increase leptin. A pulse of insulin (INS) increased serum insulin levels to 49.9+/-6.1 U/ml at 90 min and increased serum leptin by 21.3+/-6.6% at 480 min (P=0.054). LIPID decreased leptin in the face of this insulin-induced increase (LIPID+INS), between 360 min (P=0.017) and 420 min (P=0.003), with a 23% suppressive effect at 420 min. LIPID+DEX elevated leptin levels by 112.5+/-35.8% at 480 min (P=0.037), however, the Intralipid/heparin infusion did not blunt the rise of leptin under these conditions. CONCLUSIONS: These data showed that Intralipid/heparin: (i) are not sufficient to trigger the effect of dexamethasone on leptin, (ii) have an acute inhibitory effect on both fasting and insulin-stimulated leptin levels, and (iii) that this inhibitory effect cannot reverse the strong stimulatory effect of dexamethasone and insulin on serum leptin.

TNFalpha expression of subcutaneous adipose tissue in obese and morbid obese females: relationship to adipocyte LPL activity and leptin synthesis.

INTRODUCTION: Tumor necrosis factor (TNFalpha) has been invoked as an adipostat. Accordingly, the adipose tissue expression of TNFalpha has been shown to be proportional to the degree of adiposity. The regulatory role of TNFalpha in obesity may be controlled by several mechanisms. These include the inhibitory effect on LPL activity, the mediation on glucose homeostasis or the effect on leptin. To assess the role of TNFalpha in obesity we measured adipocyte TNFalpha expression in 96 females with a wide range of adiposity and with or without type 2 diabetes. We analysed the relationship between TNFalpha expression, adipocyte LPL activity, insulin resistance and leptin in this population. RESULTS: The TNFalpha and leptin expression of the adipose tissue in obese and morbid obese patients were significantly higher than in controls. Obese and morbid obese patients had slightly higher levels of LPL activity, but these differences were not significant. We observed a significant relationship between adipose TNFalpha expression and body mass index (r=0.35, P<0.001). TNFalpha expression was negatively related to LPL activity (r=-0.28, P<0.05) and positively related to leptin expression (r=0.35, P<0.001). CONCLUSION: Our results indicate that obese women, even those with morbid obesity, over-express TNFalpha in subcutaneous adipose tissue in proportion to the magnitude of the fat depot and independently of the presence of type 2 diabetes. The TNFalpha system may be a homeostatic mechanism that prevents further fat deposition by regulating LPL activity and leptin production.

[Role of lipid intake in obesity]. / Papel de la ingesta lipídica en la obesidad.

It is a commonly accepted fact that the fat in our diet plays an important role in the onset and maintenance of obesity. The excess consumption of energy associated with a high intake of fat and the greater metabolic efficiency in its use are the mechanisms suggested to support the relationship between dietary fat and adiposity. Nonetheless, the epidemiological evidence in favour of lipid intake as a promoter of obesity is not conclusive. Intervention studies, on the other hand, consistently show that there is a modest decrease in weight associated with low fat diets ad libitum, which seems to be explained by the reduction in the intake associated with such an intervention. However, this effect on weight is not maintained over time as considerable reductions in the intake of lipids in the long term seem to have no or minimal effects on corporal adiposity. It has been consistently proven that the restriction of total calories leads to greater weight losses than those achieved exclusively with fat restrictions and, on the other hand, there is very little evidence that low-fat diets per se lead to a weight loss regardless of the calorie restriction. Finally, it must be remembered that low-fat diets rich in carbohydrates are not without undesirable side effects, particularly on cardiovascular risk factors. In conclusion, a change in habits leading to an overall restriction in calories and the promotion of physical activity is a much more desirable strategy in the treatment and prevention of obesity than the apparently promising restriction of lipids in isolation.

Papel de la ingesta lipídica en la obesidad / Role of lipid intake obesity

Es un hecho comúnmente aceptado que la grasa de la deita desempeña un importante papel en el desarrollo y mantenimiento de la obesidad. El sobreconsumo energé- tico asociado a los aportes elevados de grasa y la mayor eficiencia metabólica en su utilización son los mecanismos sugeridos para apoyar la relación entre grasa dieté- tica y adiposidad. Sin embargo, las evidencias epidemiológicas a favor de la ingesta lipídica como promotora de la obesidad no resultan definitivas. Por otra parte, los estudios de intervención demuestran consistentemente una disminución modesta de peso asociada a dietas bajas en grasa ad libitum que parece explicarse por la reducción en la ingesta asociada a tal intervención. Sin embargo, este efecto sobre el peso no se mantiene en el tiempo ya que a largo plazo reducciones importantes en el aporte lipídico parecen ejercer efectos nimios o nulos sobre la adiposidad corporal. Es un hecho consistentemente probado que la restricción de calorías totales induce pérdidas de peso superiores a las conseguidas mediante la restricción lipídica exclusiva y, en cambio, existen muy pocas evidencias de que las dietas bajas en grasa per se conduzcan a la reducción ponderal con independencia de la restricción calórica. Finalmente, debe tenerse en cuenta que las dietas bajas en grasa y ricas en carbohidratos tampoco están exentas de efectos indeseables, especialmente sobre los factores de riesgo cardiovascular. En conclusión, la modificación de hábitos conducente a la restricción calórica global y la promoción de actividad física resulta una estrategia mucho más deseable que la tan prometedora restricción lipídica aislada en el tratamiento y prevención de la obesidad (AU)

It is a commonly accepted fact that the fat in our diet plays an important role in the onset and maintenance of obesity. The excess consumption of energy associated with a high intake of fat and the greater metabolic efficiency in its use are the mechanisms suggested to support the relationship between dietary fat and adiposity. Nonetheless, the epidemiological evidence in favour of lipid intake as a promoter of obesity is not conclusive. Intervention studies, on the other hand, consistently show that there is a modest decrease in weight associated with low fat diets ad libitum, which seems to be explained by the reduction in the intake associated with such an intervention. However, this effect on weight is not maintained over time as considerable reductions in the intake of lipids in the long term seem to have no or minimal effects on corporal adiposity. It has been consistently proven that the restriction of total calories leads to greater weight losses than those achieved exclusively with fat restrictions and, on the other hand, there is very little evidence that low-fat diets per se lead to a weight loss regardless of the calorie restriction. Finally, it must be remembered that low-fat diets rich in carbohydrates are not without undesirable side effects, particularly on cardiovascular risk factors. In conclusion, a change in habits leading to an overall restriction in calories and the promotion of physical activity is a much more desirable strategy in the treatment and prevention of obesity than the apparently promising restriction of lipids in isolation (AU)

The metabolic puzzle during the evolution of HIV infection.

Abnormalities in energy, protein, lipid and glucose metabolism have been described in HIV patients since the beginning of the epidemic. With the new antiretroviral agents, nutritional status and survival have improved dramatically. However, since these therapies were introduced, there have been more descriptions of metabolic abnormalities, some of which were similar to and others of which were in conflict with those reported in previous years. This paper reviews the complexity of the metabolic abnormalities in HIV infections before and after the introduction of highly active antiretroviral therapy, and discusses such etiopathogenic mechanisms as secondary infections, antiretroviral drugs and persistent immune activation, which may be involved in these derangements.

Leptin concentrations do not correlate with fat mass nor with metabolic risk factors in morbidly obese females.

AIMS: To investigate the determinants of leptinemia in a cohort of morbid obese females compared to those of normal weight and mild-to-moderate obesity, and the relationships between leptin and metabolic derangements associated with obesity. METHODS: Recruited females were: moderately obese [n=44; body mass index (BMI) 25-40 kg/m2], morbidly obese (n=34; BMI > or = 40 kg/m2) and normal weight volunteers (n=12; BMI 19-25 kg/m2). Fat mass assessed by bioelectrical impedance and fat distribution by waist-to-hip ratio (WHR) were determined in all subjects. Biochemical determinations included plasma leptin, lipoprotein profile, fasting insulin and cortisol. RESULTS: Plasma leptin values were significantly increased in morbid obese patients (54.95 +/- 1.8 ng/ml) compared to those moderately obese (30.2 +/- 1.7 ng/ml; p<0.001) and to controls (9.77 +/- 1.4 ng/ml; p<0.001). Fat and age-adjusted leptin values were not different between groups. When subjects with a BMI <40 kg/m2 were considered, plasma leptin was significantly and positively related to anthropometric variables (BMI, percentage body fat and WHR), total cholesterol, LDL-cholesterol, plasma triglycerides, AST, ALT and uric acid; and negatively with HDL-cholesterol. In contrast, when morbidly obese patients were analyzed separately, no relationships were observed between leptin concentrations and BMI, percentage of adiposity or biochemical variables. For obese patients no significant differences were observed in the adjusted leptin values with respect to the presence of diabetes, dyslipidemia or hypertension. CONCLUSIONS: In morbidly obese women, the plasma leptin concentrations, although increased, do not reflect the amount of adipose stores, and as such, factors other than simply adiposity need to be invoked to explain the variation in leptin values.

Cytokine-driven inflammatory response is associated with the hypermetabolism of AIDS patients with opportunistic infections.

BACKGROUND: To assess a possible role of systemic inflammation in the resting metabolic response in AIDS patients with active secondary infections. METHODS: Fifty-two patients with AIDS-defined criteria and concomitant active infections and 19 healthy subjects were studied. Measurements were as follows: body composition assessed by bioelectrical impedance; resting energy expenditure (REE) by 30-minute indirect calorimetry; cytokine concentrations (IL-6, IFNalpha, TNFalpha, sTNF-R1) by ELISA; C-reactive protein (CRP), erythrocyte sedimentation rate, fibrinogen, and nutritional parameters by standard techniques. RESULTS: REE adjusted for fat-free mass (REEFFM) was significantly increased in AIDS patients despite 39% of them not being hypermetabolic. The patients were undernourished and were found to have increased levels of acute-phase proteins and increased concentrations of IL-6 and sTNF-R1 relative to controls. REE parameters were positively related to CRP, ESR, ferritin, IL-6, and sTNF-R1 and negatively related to albumin, prealbumin, and transferrin. CRP was an independent predictor of REEFFM in AIDS patients and explained 25% of its variability. Patients with severe inflammation (CRP > or = 37 mg/dL) were significantly hypermetabolic with respect to patients without inflammation (CRP < 6 mg/dL) and had higher levels of IL-6 and sTNF-R1 and lower levels of albumin and prealbumin. Although no significant differences were observed with respect to the infection type, patients with tuberculosis and Pneumocystis carinii infections had higher resting metabolic and inflammatory responses, whereas patients with recurrent bacterial pneumonia were normometabolic and had lower levels of inflammatory markers. CONCLUSIONS: Resting hypermetabolism observed in AIDS patients with concurrent active infections is related to the presence and severity of systemic cytokine-driven inflammatory response, which could reflect the type of secondary infection.

Plasma acyl-estrone levels are altered in obese women.

A group of obese women (BMI>27 kg/m2; N=73) was studied together with lean controls (BMI <27 kg/m2; N=25). Three groups were defined by the compliance with: BMI lower than 27 kg/m2, glycaemia lower than 5.5 mM and insulinaemia lower than 0.2 nM (controls, group 1, N=19). The subjects with BMI>27 kg/m2, glucose >5.5 mM and insulin >0.2 nM constituted group 3 (N=41), and those with BMI>27 with glycaemia and/or insulinaemia lower than the limits set constituted group 2 (N=32). The women in group 3 had higher fat content, BMI and fat-free mass than those in group 2 and the controls. There were no changes in most plasma parameters, such as free estrone and beta-estradiol. Leptin levels were higher in groups 2 and 3 than in controls. In controls, leptin and acyl-estrone levels were well correlated with BMI and fat content; this correlation was not found in groups 2 and 3 for acyl-estrone, although it was found for leptin. Acyl-estrone levels were lower than expected in most obese women when compared to those of controls, suggesting an altered availability or function of this hormone. In obese women, acyl-estrone levels -and probably function- are lower than expected, contrasting with maintained leptin-BMI correlations. The role of insulin in the control of body weight, perhaps through acyl estrone-mediated effects, should be re-evaluated.