Association of plasma manganese levels with chronic renal failure.

Manganese (Mn) is an essential trace element involved in the formation of bone and in amino acid, lipid and carbohydrate metabolism. Mn excess may be neurotoxic to humans, affecting specific areas of the central nervous system. However, relatively little is known about its physiological and/or toxicological effects, and very few data are available concerning the role of Mn in chronic renal failure (CRF). This paper describes a 12-month study of the evolution of plasma Mn levels in predialysis patients with CRF and the relationship with energy and macronutrient intake. The participants in this trial were 64 patients with CRF in predialysis and 62 healthy controls. Plasma levels of creatinine, urea, uric acid, total protein and Mn were measured. The glomerular filtration rate (GFR) was calculated using the Cockcroft-Gault index. The CRF patients had higher plasma levels of creatinine, urea, uric acid and Mn and a lower GFR than the controls. Plasma Mn was positively correlated with creatinine, plasma urea and plasma uric acid and was negatively correlated with the GFR and the intake of energy and macronutrients. In conclusion, CRF in predialysis patients is associated with increases in circulating levels of Mn.

Exposure to bis(maltolato)oxovanadium(IV) increases levels of hepcidin mRNA and impairs the homeostasis of iron but not that of manganese.

The aim of this study was to examine whether alterations in iron homeostasis, caused by exposure to vanadium, are related to changes in the gene expression of hepatic hepcidin. Two groups of rats were examined: control and vanadium-exposed. Vanadium, as bis(maltolato)oxovanadium(IV) was supplied in the drinking water. The experiment had a duration of five weeks. Iron and manganese were measured in excreta, serum and tissues. Leptin, ferritin, IL-1ß, IL-6, TNF-α, red blood cells, haemoglobin and haematocrit were determined. Protein carbonyl group levels and hepcidin gene expression were determined in the liver. In the vanadium-exposed rats, iron absorption, serum iron and leptin and all haematological parameters decreased. Levels of IL-6, TNF-α and ferritin in serum and of iron in the liver, spleen and heart increased. In the liver, levels of protein carbonyl groups and hepcidin mRNA were also higher in the vanadium-exposed group. Exposure to vanadium did not modify manganese homeostasis. The results obtained from this study provide the first evidence that bis(maltolato)oxovanadium(IV) produces an increase in the gene expression of the hepcidin, possibly caused by an inflammatory process. Both factors could be the cause of alterations in Fe homeostasis and the appearance of anaemia. However, Mn homeostasis was not affected.

Changes in iron metabolism and oxidative status in STZ-induced diabetic rats treated with bis(maltolato) oxovanadium (IV) as an antidiabetic agent.

The role of vanadium as a micronutrient and hypoglycaemic agent has yet to be fully clarified. The present study was undertaken to investigate changes in the metabolism of iron and in antioxidant defences of diabetic STZ rats following treatment with vanadium. Four groups were examined: control; diabetic; diabetic treated with 1 mgV/day; and Diabetic treated with 3 mgV/day. The vanadium was supplied in drinking water as bis(maltolato) oxovanadium (IV) (BMOV). The experiment had a duration of five weeks. Iron was measured in food, faeces, urine, serum, muscle, kidney, liver, spleen, and femur. Superoxide dismutase, catalase, NAD(P)H: quinone-oxidoreductase-1 (NQO1) activity, and protein carbonyl group levels in the liver were determined. In the diabetic rats, higher levels of Fe absorbed, Fe content in kidney, muscle, and femur, and NQO1 activity were recorded, together with decreased catalase activity, in comparison with the control rats. In the rats treated with 3 mgV/day, there was a significant decrease in fasting glycaemia, Fe content in the liver, spleen, and heart, catalase activity, and levels of protein carbonyl groups in comparison with the diabetic group. In conclusion BMOV was a dose-dependent hypoglycaemic agent. Treatment with 3 mgV/day provoked increased Fe deposits in the tissues, which promoted a protein oxidative damage in the liver.

Iron: protector or risk factor for cardiovascular disease? Still controversial.

Iron is the second most abundant metal in the Earth's crust. Despite being present in trace amounts, it is an essential trace element for the human body, although it can also be toxic due to oxidative stress generation by the Fenton reaction, causing organic biomolecule oxidation. This process is the basis of numerous pathologies, including cardiovascular diseases (CVD). The relationship between iron and cardiovascular disease was proposed in 1981 by Jerome Sullivan. Since then, numerous epidemiological studies have been conducted to test this hypothesis. The aim of this review is to present the main findings of the chief epidemiological studies published during the last 32 years, since Sullivan formulated his iron hypothesis, suggesting that this element might act as a risk factor for cardiovascular disease. We have analyzed 55 studies, of which 27 supported the iron hypothesis, 20 found no evidence to support it and eight were contrary to the iron hypothesis. Our results suggest that there is not a high level of evidence which supports the hypothesis that the iron may be associated with CVD. Despite the large number of studies published to date, the role of iron in cardiovascular disease still generates a fair amount of debate, due to a marked disparity in results.

Accumulation of scandium in plasma in patients with chronic renal failure.

Scandium (Sc) is an element with many industrial applications, but relatively little is known about its physiological and/or toxicological effects, and very little data are available concerning the role of Sc in chronic renal failure (CRF). This paper examines the changes in plasma levels of Sc in predialysis patients with CRF and the relationship with blood parameters. The participants in this trial were 48 patients with CRF in predialysis and 53 healthy controls. Erythrocyte, haemoglobin, and haematocrit counts in blood were determined, and levels of creatinine, urea, uric acid, albumin, total protein and Sc were measured in plasma. The glomerular filtration rate (GFR) was calculated using the Cockcroft-Gault index. The CRF patients were found to have higher plasma levels of creatinine, urea, uric acid, albumin, total protein, and Sc and a lower GFR than that the controls. Scandium in plasma was positively correlated with creatinine and plasma urea and negatively correlated with GFR, haemoglobin, and haematocrit and was associated with the risk of lower levels of erythrocytes, haemoglobin, and haematocrit. CRF was associated with increases in the circulating levels of scandium.

Valores de referencia para la exposición a los riesgos psicosociales en la polbaicón Asalariada en España / No disponible

No disponible

Toenail cerium levels and risk of a first acute myocardial infarction: the EURAMIC and heavy metals study.

The association between cerium status and risk of first acute myocardial infarction (AMI) was examined in a case-control study in 10 centres from Europe and Israel. Cerium in toenails was assessed by neutron activation analysis in 684 cases and 724 controls aged 70 years or younger. Mean concentrations of cerium were 186 and 173 microg/kg in cases and controls, respectively. Cerium was positively associated with low socio-economic status, smoking, mercury, zinc and scandium (p0.001). Cases had significantly higher levels of cerium than controls after adjustment for age and centre (case-control ratio 1.074; 95% CI 1.002-1.151) and increased in further adjustment for other cardiovascular risk factors 1.085; 95% CI 1.025-1.149. The risk after adjustment for age and centre was higher with increasing cerium levels (p for trend=0.02). After adjustment for BMI, history of hypertension, smoking, alcohol intake, diabetes, family history of CHD, beta-carotene, lycopene, alpha-tocopherol, selenium, mercury and scandium, the OR for the highest quintile was 1.43 (95% CI 0.85-2.41; p-trend 0.08). When we applied this same model in non-smokers the odds ratios in the 4th and 5th quintiles of cerium as compared with the lowest were 2.09 (95% CI 1.05-4.16) and 2.81 (95% CI 1.21-6.52), respectively, p-trend 0.011. Our results suggest that toenail cerium levels may be associated with an increased risk of AMI, but more research is warranted to shed further light and fully understand the plausibility and public health implications of these findings.

Low toenail chromium concentration and increased risk of nonfatal myocardial infarction.

Chromium intake may increase insulin sensitivity, glucose tolerance, and the ratio of high density lipoprotein cholesterol to low density lipoprotein cholesterol. However, the epidemiologic evidence on the association between chromium and cardiovascular disease is very limited. To determine whether low toenail chromium concentrations were associated with risk of nonfatal myocardial infarction, the authors conducted an incident, population-based, case-control study in eight European countries and Israel in 1991-1992. Cases (n = 684) were men with a first diagnosis of myocardial infarction recruited from the coronary units of participating hospitals. Controls (n = 724) were men selected randomly from population registers (five study centers) or through other sources, such as hospitalized patients (three centers), general practitioners' practices (one center), or relatives or friends of cases (one center). Toenail chromium concentration was assessed by neutron activation analysis. Average toenail chromium concentrations were 1.10 mug/g in cases (95% confidence interval: 1.01, 1.18) and 1.30 mug/g in controls (95% CI: 1.21, 1.40). Multivariate odds ratios for quintiles 2-5 were 0.82 (95% CI: 0.52, 1.31), 0.68 (95% CI: 0.43, 1.08), 0.60 (95% CI: 0.37, 0.97), and 0.59 (95% CI: 0.37, 0.95). Toenail chromium concentration was inversely associated with the risk of a first myocardial infarction in men. These results add to an increasing body of evidence that points to the importance of chromium for cardiovascular health.

Readmission rate as an indicator of hospital performance: the case of Spain.

OBJECTIVES: Hospital readmission rate is currently used as a quality of care indicator, although its validity has not been established. Our aims were to identify the frequency and characteristics of potential avoidable readmissions and to compare the assessment of quality of care derived from readmission rate with other measure of quality (judgment of experts). DESIGN: cross-sectional observational study; SETTING: acute care hospital located in Marbella, South of Spain; STUDY PARTICIPANTS: random sample of patients readmitted at the hospital within six months from discharge (n = 363); INTERVENTIONS: review of clinical records by a pair of observers to assess the causes of readmissions and their potential avoidability; MAIN MEASURES: logistic regression analysis to identify the variables from the databases of hospital discharges which are related to avoidability of readmissions. Determination of sensitivity and specificity of different definitions of readmission rate to detect avoidable situations. RESULTS: Nineteen percent of readmissions were considered potentially avoidable. Variables related to readmission avoidability were (i) time elapsed between index admission and readmission and (ii) difference in diagnoses of both episodes. None of the definitions of readmission rate used in this study provided adequate values of sensitivity and specificity in the identification of potentially avoidable readmissions. CONCLUSIONS: Most readmissions in our hospital were unavoidable. Thus, readmission rate might not be considered a valid indicator of quality of care.

Vegetable consumption and carotenoids in plasma and adipose tissue in Malaga, Spain.

OBJECTIVE: To study relationships between habitual dietary intake, adipose tissue concentrations of alpha-carotene, beta-carotene and lycopene, and plasma concentrations of alpha- and beta-carotene. DESIGN: Cross-sectional study including assessment of food habits by a food frequency questionnaire and 48-hour recall and determination of carotenoid concentrations in adipose tissue and plasma. SUBJECTS: 51 women (mean age of 62 years) from the control group of the European Community Multicentre Study on Antioxidants, Myocardial Infarction, and Breast Cancer (EURAMIC), Málaga, Spain. RESULTS: In adipose tissue, beta-carotene was correlated with consumption of green pepper (r = 0.36; p < 0.05) and lycopene with total fruit/vegetable intake (r = 0.28; p < 0.05), green pepper (r = 0.31; p < 0.05), and carrot (r = 0.25; p < 0.10). In plasma, beta-carotene was correlated with total fruit/vegetable intake (r = 0.29; p < 0.10), lettuce (r = 0.34; p < 0.05), tomato (r = 0.26; p < 0.10), and lycopene with total fruit/vegetable intake (r = 0.27; p < 0.10). Age-, BMI- and waist circumference-adjusted regression coefficients for the regression of logn-transformed adipose and plasma concentrations on consumption of specific fruits and vegetables (per 100 g/day) were calculated. In adipose tissue, coefficients were: 1.50 (p < 0.05) for alpha-carotene/carrot; 1.90 (p < 0.10) and 0.51 (p < 0.10) for beta-carotene/green pepper and lettuce; 2.02 (p < 0.05), 1.25 (p < 0.05) and 0.18 (p < 0.05) for lycopene/green pepper, carrot and total fruit/vegetable intake. In plasma, coefficients were 1.14 (p < 0.05) and 0.21 (p < 0.05) for beta-carotene/lettuce and total fruit/vegetable intake. CONCLUSIONS: Consumption of fruit and vegetables could be linked directly to carotenoid concentrations in adipose tissue and plasma. Although associations with individual food items are related to their carotenoid contents, the absorption and distribution of carotenoids needs more attention to improve their usefulness as biomarkers of exposure.

Mercury, fish oils, and the risk of myocardial infarction.

BACKGROUND: It has been suggested that mercury, a highly reactive heavy metal with no known physiologic activity, increases the risk of cardiovascular disease. Because fish intake is a major source of exposure to mercury, the mercury content of fish may counteract the beneficial effects of its n-3 fatty acids. METHODS: In a case-control study conducted in eight European countries and Israel, we evaluated the joint association of mercury levels in toenail clippings and docosahexaenoic acid (C22:6n-3, or DHA) levels in adipose tissue with the risk of a first myocardial infarction among men. The patients were 684 men with a first diagnosis of myocardial infarction. The controls were 724 men selected to be representative of the same populations. RESULTS: The average toenail mercury level in controls was 0.25 microg per gram. After adjustment for the DHA level and coronary risk factors, the mercury levels in the patients were 15 percent higher than those in controls (95 percent confidence interval, 5 to 25 percent). The risk-factor-adjusted odds ratio for myocardial infarction associated with the highest as compared with the lowest quintile of mercury was 2.16 (95 percent confidence interval, 1.09 to 4.29; P for trend=0.006). After adjustment for the mercury level, the DHA level was inversely associated with the risk of myocardial infarction (odds ratio for the highest vs. the lowest quintile, 0.59; 95 percent confidence interval, 0.30 to 1.19; P for trend=0.02). CONCLUSIONS: The toenail mercury level was directly associated with the risk of myocardial infarction, and the adipose-tissue DHA level was inversely associated with the risk. High mercury content may diminish the cardioprotective effect of fish intake.

[Analysis of the causes and potential avoidability of readmissions in an acute patients' hospital]. / Análisis de las causas de los reingresos en un hospital de agudos y su evitabilidad potencial.

BACKGROUND: Rates of hospital readmissions are used as indicators of quality of health care. Yet specific causes of readmissions have not been sufficiently studied and an unified definition of such an indicator is lacking. Our goal was to determine the causes and potential avoidability of readmissions in our hospital and to identify a suitable definition of this indicator. DESIGN: Cross sectional study. SETTING: Hospital Costa del Sol (Marbella, Málaga). Subjects of study: Random sample of hospital discharges followed by a new admission within the next 6 months (n = 363). INTERVENTIONS: Determination of the causes and potential avoidability of readmissions, by means of a peer-review of medical records. Descriptive and logistic regression analysis of the variables contained in the Minimum Basic Data Set (MBDS) and related to the avoidability of readmissions. RESULTS: 19% (95% CI: 15.0-23.0) of hospital readmissions within 6 months after hospital discharge were attributed to potentially avoidable situations if the applied medical care had been modified during the previous episode. This figure reached 37% (95% CI: 27.4-47.3) for surgical services, 13% (95% CI: 8.7-17.6) for medical services and 12% (95% CI: 2.9-20.6) for obstetrics. The MBDS variables related to the potential avoidability of readmissions were, for the whole hospital, 1) the shorter interval from the previous discharge and 2) the difference of diagnosis between both episodes. CONCLUSIONS: Most hospital readmissions are due to non-avoidable situations if the applied medical care had been modified during the previous episode. In order to detect potentially avoidable situations, definitions of readmission rates should only include early readmissions with a chief diagnosis other than that in the previous admission.

Análisis de las causas de los reingresos en un hospital de agudos y su evitabilidad potencial / Analysis of the causes and potential avoidability of readmissions in an acute patients' hospital

FUNDAMENTO: Las tasas de reingresos hospitalarios se utilizan como indicadores de calidad asistencial, aunque las causas de éstos no están suficientemente estudiadas ni existe una definición unificada del indicador. Nos planteamos determinar las causas y potencial evitabilidad de los reingresos en nuestro centro e identificar su definición más adecuada. PACIENTES Y MÉTODOS: Estudio observacional transversal. Ámbito: Hospital Costa del Sol (Marbella, Málaga). Sujetos de estudio: muestra aleatoria de reingresos en 6 meses del alta (n = 363).Instrumentalización: determinación de las causas y potencial evitabilidad de los reingresos mediante revisión de historias clínicas por pares de observadores. Análisis descriptivo y de regresión logística sobre las variables del Conjunto Mínimo Básico de Datos (CMBD) que se relacionan con la evitabilidad de los reingresos. RESULTADOS: El 19 por ciento (intervalo de confianza [IC] del 95 por ciento, 15,0-23,0) de los reingresos hospitalarios en 6 meses del alta se atribuyeron a situaciones potencialmente evitables de haberse modificado los cuidados aplicados durante el episodio previo. Este porcentaje alcanzó el 37 por ciento (IC del 95 por ciento, 27,4-47,3) para servicios quirúrgicos, el 13 por ciento (IC del 95 por ciento, 8,7-17,6) para servicios médicos y el 12 por ciento (IC del 95 por ciento, 2,9-20,6) para obstetricia. Las variables relacionadas con la potencial evitabilidad de los reingresos fueron, en el conjunto del hospital, la menor duración del plazo desde el alta previa y la diferencia de diagnóstico entre ambos episodios.CONCLUSIONES: La mayor parte de los reingresos hospitalarios se deben a situaciones no evitables mediante la modificación de los cuidados aplicados durante el ingreso previo. Las definiciones de tasas de reingresos deberían incluir solamente los reingresos tempranos y con un diagnóstico principal diferente al del ingreso previo, con el fin de detectar fundamentalmente situaciones potencialmente evitables (AU)

Association between toenail scandium levels and risk of acute myocardial infarction in European men: the EURAMIC and Heavy Metals Study.

The association between scandium status and risk of acute myocardial infarction (MI) was examined in a multicentre case control study in 10 centres from Europe and Israel. Scandium in toenails was assessed in 684 cases and 724 controls less than 70 years of age. Mean concentrations of toenail scandium were 6.74 micro/kg in cases and 7.75 microg/kg in controls. Scandium among controls, adjusted for age and centre was positively associated with concentrations of lycopene and oleic acid in adipose tissue (P = 0.002 for both nutrients). Pearson correlations adjusted for age and centre were significant (P < 0.05) between scandium and lycopene (r = 0.08), zinc (r = 0.08), mercury (r = 0.18) and oleic acid (r = 0.21). Overall, cases had lower levels of scandium than controls after adjustment for age and centre (case control ratio, 0.87; 95% CI 0.79-0.96). This association persisted after adjustment for other cardiovascular risk factors (case-control ratio 0.88; 95% CI, 0.79-0.98). The risk of MI at high scandium levels was reduced after adjustment for age and centre (P-trend = 0.04). Further adjustments for BMI, history of hypertension, smoking, alcohol intake, diabetes, family history of CHD, alpha-tocopherol, beta-carotene, lycopene, selenium and mercury slightly attenuated this trend (P = 0.055). Our results suggest that toenail scandium level is associated with a reduced risk of acute MI, but we are uncertain whether this element can really play a protective role in the development of CHD. Without an identified plausible mechanism, these results should be regarded as preliminary and should be tested in future studies.