Competency assessment of residents of Intensive Care Medicine through a simulation-based objective structured clinical evaluation (OSCE). A multicenter observational study.

OBJECTIVES: The current official model of training in Intensive Care Medicine (ICM) in Spain is based on exposure to experiences through clinical rotations. The main objective was to determine the level of competency (I novice to V independent practitioner) achieved by the residents at the end of the 3rd year of training (R3) in ICM through a simulation-based OSCE. Secondary objectives were: (1) To identify gaps in performance, and (2) To investigate the reliability and feasibility of conducting simulation-based assessment at multiple sites. DESIGN: Observational multicenter study. SETTING: Thirteen Spanish ICU Departments. PARTICIPANTS: Thirty six R3. INTERVENTION: The participants performed on five, 15-min, high-fidelity crisis scenarios in four simulation centers. The performances were video recorded for later scoring by trained raters. MAIN VARIABLES OF INTEREST: Via a Delphi technique, an independent panel of expert intensivists identified critical essential performance elements (CEPE) for each scenario to define the levels of competency. RESULTS: A total of 176 performances were analyzed. The internal consistency of the check-lists were adequate (KR-20 range 0.64-0.79). Inter-rater reliability was strong [median Intraclass Correlation Coefficient across scenarios: 0.89 (0.65-0.97)]. Competency levels achieved by R3 were: Level I (18.8%), II (35.2%), III (42.6%), IV/V (3.4%). Overall, a great heterogeneity in performance was observed. CONCLUSION: The expected level of competency after one year in the ICU was achieved only in half of the performances. A more evidence-based educational approach is needed. Multiple center simulation-based assessment showed feasibility and reliability as an evaluation method of competency. TRIAL REGISTRATION: COBALIDATION. NCT04278976. (https://register. CLINICALTRIALS: gov).

Competency assessment of residents of Intensive Care Medicine through a simulation-based objective structured clinical evaluation (OSCE). A multicenter observational study / Evaluación del nivel de competencia de residentes de Medicina Intensiva mediante una evaluación clínica, objetiva y estructurada basada en simulación (ECOE). Estudio multicéntrico observacional

Objectives The current official model of training in Intensive Care Medicine (ICM) in Spain is based on exposure to experiences through clinical rotations. The main objective was to determine the level of competency (I novice to V independent practitioner) achieved by the residents at the end of the 3rd year of training (R3) in ICM through a simulation-based OSCE. Secondary objectives were: (1) To identify gaps in performance, and (2) To investigate the reliability and feasibility of conducting simulation-based assessment at multiple sites. Design Observational multicenter study. Setting Thirteen Spanish ICU Departments. Participants Thirty six R3. Intervention The participants performed on five, 15-min, high-fidelity crisis scenarios in four simulation centers. The performances were video recorded for later scoring by trained raters. Main variables of interes Via a Delphi technique, an independent panel of expert intensivists identified critical essential performance elements (CEPE) for each scenario to define the levels of competency. Results A total of 176 performances were analyzed. The internal consistency of the check-lists were adequate (KR-20 range 0.64–0.79). Inter-rater reliability was strong [median Intraclass Correlation Coefficient across scenarios: 0.89 (0.65–0.97)]. Competency levels achieved by R3 were: Level I (18.8%), II (35.2%), III (42.6%), IV/V (3.4%). Overall, a great heterogeneity in performance was observed. Conclusio The expected level of competency after one year in the ICU was achieved only in half of the performances. A more evidence-based educational approach is needed. Multiple center simulation-based assessment showed feasibility and reliability as an evaluation method of competency (AU)

Objetivos El modelo de formación en medicina intensiva (MI) en España se basa en la experiencia adquirida durante una serie de rotaciones programadas por diferentes áreas clínicas. El objetivo principal del estudio fue determinar el nivel de competencia (I principiante – V autónomo) de los residentes de MI al finalizar el tercer año de residencia (R3) mediante una ECOE basada en simulación. Objetivos secundarios: 1) identificar brechas en el desempeño; 2) investigar la fiabilidad y validez de una ECOE simulada multicéntrica como método de evaluación. Diseño Estudio multicéntrico observacional. Ámbito Trece servicios españoles de Medicina Intensiva. Participantes Treinta y seis R3. Intervención Los 36 R3 participaron en cinco escenarios clínicos simulados de 15 minutos de duración en cuatro centros de simulación. Las actuaciones se grabaron en video y posteriormente se calificaron por pares de expertos. Variables de interés principales Un panel de intensivistas expertos seleccionó mediante el método Delphi los elementos críticos esenciales de cada escenario para definir los niveles de competencia. Resultados La consistencia interna de los listados de verificación fue adecuada (KR-20:0,64-0,79). La fiabilidad interjueces fue elevada (coeficiente de correlación intraclase [mediana]: 0,89 [0,65-0,97]). Los niveles de competencia conseguidos fueron: nivel I (18,8%), II (35,2%), III (42,6%), IV/V (3,4%). Globalmente, se observó una gran heterogeneidad en el desempeño. Conclusión El nivel de competencia esperado se logró únicamente en la mitad de las actuaciones. Se necesita un modelo de formación más basado en objetivos y evidencias. La evaluación mediante escenarios simulados en múltiples centros demostró ser factible y fiable (AU)

Acceptance and validity of the methods used to implement a competency based medical education programme in an Intensive Care Department of a teaching referral center.

OBJECTIVES: 1. To determine the satisfaction of tutors and residents with a specific methodology used to implement CoBaTrICE. 2. To determine the reliability and validity of the global rating scales designed ad hoc to assess the performance of the residents for training purposes. DESIGN: Prospective cohort study. PARTICIPANTS: All the residents and tutors of the ICU Department of the Hospital Universitario y Politécnico la Fe de Valencia. INTERVENTION: CoBaTrICE implementation started in March 2016, it was based on: (1) Training the tutors in feedback techniques; (2) Performing multiple objective and structured work based assessments to achieve the competences of the program; and (3) The use of an electronic portfolio to promote learning reflection and to collect the evidence that learning was taking place. METHODS: The acceptance of CoBaTrICE was explored through a satisfaction survey conducted after 9 months of implementation of the training program. The 15 residents and 5 tutors of the ICU Department were asked about the methodology of the formative assessments, the quality of the feedback, self-learning regulation and the electronic portfolio usefulness. The validity of the global rating scales was assessed through the tests alfa de Cronbach, reliability and generalizability indexes, and intraclass correlation coefficient. RESULTS: The implementation of CoBaTrICE was satisfactory in all the dimensions studied. The global rating scales used for formative purposes showed reliability and validity. CONCLUSIONS: The methodology used to implement CoBaTrICE was highly valued by tutors and residents. The global rating scales used for formative purposes showed reliability and validity.

Impact of model fat emulsions on sensory perception using repeated spoon to spoon ingestion.

Eating is a dynamic behaviour, in which food interacts with the mechanical and physiological environment of the mouth. This dynamic interaction changes the oral surfaces leaving particles of food and building up a film on the oral surfaces, which may impact on the temporal perception during the eating experience. The effect of repeated spoon to spoon ingestion of oil in water emulsion products (2%-50% w/w oil) was evaluated using descriptive in-mouth and after swallowing sensory attributes. Descriptive sensory analysis indicated that fatty mouthfeel and afterfeel perception (measured post swallowing) increased with the number of spoonfuls for emulsions containing 50% fat. This effect is likely due to the build-up of oil droplet layers deposited on the mouth surfaces. There was an enhancement of fatty afterfeel intensity for 50% fat emulsions containing the more lipophilic aroma ethylhexanoate compared to ethyl butanoate, indicating a cross-modal interaction. No increase in these attributes from spoon to spoon was observed for the low oil emulsions; since most of the oil in the emulsion was swallowed and very little oil was likely to be left in the mouth. Sweetness perception increased as fat level increased in the emulsion due to an increase in the effective concentration of sugar in the aqueous phase. However, the sweetness perceived did not change from spoon to spoon, suggesting that any oil-droplets deposited on the oral surfaces did not form a complete barrier, restricting access of the sucrose to the taste buds. This study highlights the importance of measuring the dynamic nature of eating and demonstrated change in sensory perception occurring with repeated ingestion of model emulsions, which was likely due to a change in mouth environment.

Initial experience of use of tolvaptan in critically ill patients with fluid overload.

WHAT IS KNOWN AND OBJECTIVE: Positive volume balance is related with high mortality in critically ill patients. We describe our experience in the use of tolvaptan in patients with fluid overload. CASE SUMMARY: Six patients in the recovery phase from septic shock were included. All patients achieved an increase in diuresis after the first day, with a median fluid balance variation of -2362 (-485 to -3447) mL. At the end of treatment, median fluid balance variation was -9080 (-26,784 to -4395) mL. WHAT IS NEW AND CONCLUSION: Tolvaptan could be an option in critically ill patients with fluid overload and resistant or not treatable with conventional diuretics.

Macrophages are novel sites of expression and regulation of retinol binding protein-4 (RBP4).

Obesity is linked to a low-level chronic inflammatory state that may contribute to the development of associated metabolic complications. Retinol-binding protein 4 (RBP4) is an adipokine associated with parameters of obesity including insulin resistance indices, body mass index, waist circumference, lipid profile, and recently, with circulating inflammatory factors. Due to the infiltration of adipose tissue in obesity by macrophages derived from circulating monocytes and, on the other hand, the existence of a close genetic relationship between adipocytes and macrophages, we decided to examine if RBP4 is expressed in monocytes and/or primary human macrophages. While we did not detect expression of RBP4 in undifferentiated monocytes, RBP4 expression became evident during the differentiation of monocytes into macrophages and was highest in differentiated macrophages. Once we demonstrated the expression of RBP4 in macrophages, we checked if RBP4 expression could be regulated by inflammatory stimuli such as tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), or the endotoxin lipopolysaccharide (LPS). We observed that while RBP4 expression was strongly inhibited by TNF-alpha and LPS, it was not affected by IL-6. Our results highlight the complexity behind the regulation of this adipokine and demonstrate that RBP4 expression in macrophages could be modulated by inflammatory stimuli.

Adult subjects with Prader-Willi syndrome show more low-grade systemic inflammation than matched obese subjects.

AIM: Adult subjects with Prader-Willi syndrome (PWS) may show several conditions that are associated with an activation of innate immunity such as obesity, deficient GH secretion or hypogonadism. Our aim was to study whether obese adult PWS subjects show an additional low-grade systemic inflammation (LGSI) in relation to obese adult non-PWS subjects and lean healthy control subjects before and after a standardized liquid meal. METHODS: Seven obese adult PWS subjects, 7 matched obese non-PWS subjects and 7 lean healthy control subjects were studied for 6 h from the administration of a standard liquid meal. RESULTS: Compared to non-PWS, PWS subjects showed higher plasma concentrations of C-reactive protein (CRP) (p=0.030), complement component C3 (p=0.018), interleukin(IL)-18 (p=0.048), and IL-6 (p=0.041) that persisted post-prandially elevated for CRP (p<0.0001), C3 (p=0.015), and IL-18 (p=0.003). Tumor necrosis factor(TNF)-alpha did not differ between the 3 groups. These results were independent from IGF-I levels, homeostasis model assessment index, and body mass index (BMI). In male subjects with PWS, testosterone levels correlated to IL-18 (r=-0,646, p=0.041). CONCLUSIONS: Compared to matched non-PWS subjects, the obese PWS subjects in this study showed an additional LGSI that persisted postprandially and was independent from BMI, insulin resistance, and deficient GH secretion. However, in PWS males, high IL-18 levels were related to low testosterone concentrations.

Effect of weight loss induced by gastric bypass on proinflammatory interleukin-18, soluble tumour necrosis factor-alpha receptors, C-reactive protein and adiponectin in morbidly obese patients.

OBJECTIVE: Interleukin-18 (IL-18) is a potent proinflammatory cytokine whose role in human obesity has recently been suggested. The aim of our study was to analyse in morbidly obese patients undergoing gastric bypass, the relationship of IL-18 with insulin resistance and with proinflammatory cytokines (tumour necrosis factor-alpha receptors, sTNFR), C-reactive protein (CRP) and with adiponectin. DESIGN: Observational and prospective study. PATIENTS: Sixty-five morbidly obese patients, aged 45 +/- 8.9 years, were studied before and 12 months after gastric bypass. MEASUREMENTS: We analysed plasma concentrations of IL-18, sTNFR, CRP and adiponectin. RESULTS: Plasma concentrations of sTNFR2, IL-18 and CRP were decreased and adiponectin significantly increased after bypass surgery. In the multiple regression analysis, preoperative values of IL-18 remained significantly associated with preoperative triglycerides (beta = 0.47, P = 0.005) and TNFR2 (beta = 0.47, P = 0.004). R(2) for the model = 0.38. Postoperative IL-18 concentrations in the multiple regression analysis were significantly associated with postoperative homeostasis model assessment of insulin resistance (HOMA-IR) (beta = 0.092, P = 0.019) and triglycerides (beta = 0.40, P = 0.036). R(2) for the model = 0.46. IL-18 did not correlate with body mass index, fat mass, fat-free mass or body fat. No relationship was either found between adiponectin and IL-18, TNFR1 and -2 and CRP. CONCLUSIONS: Massive weight loss induced by gastric bypass reduces IL-18, TNFR2 and CRP. IL-18 might be a marker of the chronic inflammatory process underlying insulin resistance but its lack of association with anthropometric and body composition parameters does not support a major secretion by human adipocytes. IL-18 and sTNFR1 and -2 do not play a main role in the inhibition of the secretion of adiponectin.

Lower heart rate variability is associated with higher plasma concentrations of IL-6 in type 1 diabetes.

OBJECTIVE: In type 1 diabetes, cardiovascular autonomic neuropathy (CAN) is associated with cardiovascular risk factors related to insulin resistance, which in turn are associated with low-grade systemic inflammation. Reduced heart rate variability (HRV) is considered one of the first indicators of CAN. Since the autonomic nervous system interacts with systemic inflammation, we evaluated CAN to study its possible association with low-grade systemic inflammation. DESIGN: Cross-sectional study of a group of 120 subjects diagnosed with type 1 diabetes mellitus 14 years before. METHODS: Information recorded: 1) clinical characteristics: sex, age, body mass index, waist-to-hip ratio (WHR), blood pressure (BP), smoking, alcohol intake, insulin dose, HbA1c, and lipid profile; 2) plasma levels of soluble fractions of tumour necrosis factor alpha receptors 1 and 2, IL-6, and C-reactive protein; 3) insulin resistance by estimation of the glucose disposal rate (eGDR); and 4) tests for CAN: HRV in response to deep breathing (E/I ratio), HRV in response to the Valsalva maneuver, and changes in systolic BP responding to standing. RESULTS: A significant negative correlation was found between E/I ratio and plasma concentrations of IL-6 (r=-0.244, P=0.032), which remained significant after adjusting for potential confounding factors (age, sex, HbA1c, WHR, diastolic BP, triglycerides, HDL-cholesterol, retinopathy, nephropathy, peripheral neuropathy, insulin dose, and smoking; r=-0.231, P=0.039). No other significant associations were found between inflammation-related proteins, tests for CAN, and eGDR. CONCLUSIONS: These findings suggest a link between low-grade inflammation and early alterations of CAN in type 1 diabetes and may be of importance in the pathogenesis of CAN and/or its clinical implications.

IL-18: relationship with anthropometry, body composition parameters, leptin and arterial hypertension.

OBJECTIVE: Interleukin-18 (IL-18) is a potent pro-inflammatory cytokine with potential atherogenic properties whose role in human obesity has been recently suggested. The aim of our study was to analyze the physiologic distribution of IL-18 among sexes and all decades of the adult life in a healthy population randomly selected and to study its relationship with anthropometric, body composition measurements and leptin concentrations. We also studied the relationship of IL-18 with smoking and arterial hypertension, known risk factors implicated in atherogenesis. MATERIALS AND METHODS: One hundred and thirty four men and 127 healthy women were included in the study. Plasma concentrations of IL-18 and leptin were determined in all subjects. Body composition was evaluated by bioelectrical impedanciometry. RESULTS: IL-18 was distributed similarly in men and women and throughout decades. No significant differences were found in IL-18 between obese and normal-weight men and women according to their body mass index and body fat content. Higher IL-18 concentrations were found in subjects with arterial hypertension. In the bivariate correlation analysis only waist to hip ratio correlated weakly with IL-18 in the whole population (r=0.12, p=0.04). In the multiple regression analysis the relationship between IL-18 and waist to hip ratio lost significance after adjusting for age, sex and body mass index. However, IL-18 remained associated with arterial hypertension (adjusted r2=0.25, p=0.023). CONCLUSIONS: The lack of correlation between IL-18 with anthropometric, body composition variables and leptin in our healthy population argues against a role of this cytokine in obesity. Moreover, our findings suggest the implication of this interleukin in the atherogenic process induced by arterial hypertension.

Antibiotic prescription for community-acquired pneumonia in the intensive care unit: impact of adherence to Infectious Diseases Society of America guidelines on survival.

BACKGROUND: The purpose of our study was to analyze prognostic factors associated with mortality for patients with severe community-acquired pneumonia (CAP). METHODS: We conducted a prospective multicenter study including all patients with CAP admitted to the intensive care unit during a 15-month period in 33 Spanish hospitals. Admission data and data on the evolution of the disease were recorded. Multivariate analysis was performed using the SPSS statistical package (SPSS). RESULTS: A total of 529 patients with severe CAP were enrolled; the mean age (+/-SD) was 59.9+/-16.1 years, and the mean Acute Physiology and Chronic Health Evaluation (APACHE) II score (+/-SD) was 18.9+/-7.4. Overall mortality among patients in the intensive case unit was 27.9% (148 patients). The rate of adherence to Infectious Diseases Society of America (IDSA) guidelines was 57.8%. Significantly higher mortality was documented among patients with nonadherence to treatment (33.2% vs. 24.2%). Multivariate analysis identified age (odds ratio [OR], 1.7), APACHE II score (OR, 4.1), nonadherence to IDSA guidelines (OR, 1.6), and immunocompromise (OR, 1.9) as the variables present at admission to the intensive care unit that were independently associated with death in the intensive care unit. In 15 (75%) of 20 cases of Pseudomonas aeruginosa infection, the antimicrobial treatment at admission was inadequate (including 8 of 15 cases involving patients with adherence to IDSA guidelines). Chronic obstructive pulmonary disease (OR, 17.9), malignancy (OR, 11.0), previous antibiotic exposure (OR, 6.2), and radiographic findings demonstrating rapid spread of disease (OR, 3.9) were associated with P. aeruginosa pneumonia. CONCLUSIONS: Better adherence to IDSA guidelines would help to improve survival among patients with severe CAP. Pseudomonas coverage should be considered for patients with chronic obstructive pulmonary disease, malignancy, or recent antibiotic exposure.

The tumour necrosis factor (TNF)-alpha system is activated in accordance with pulse pressure in normotensive subjects with type 1 diabetes mellitus.

OBJECTIVE: Pulse pressure (PP) and inflammation are important predictors of cardiovascular disease (CVD), even in the normotensive. The age-related increase in PP can be diagnosed up to 20 years earlier in subjects with type 1 diabetes mellitus (T1DM) than in the general population. Some evidence suggests that PP can stimulate inflammation. Our aim was to study the relationship between PP and plasma inflammatory proteins in normotensive subjects with T1DM. DESIGN: This was a cross-sectional study of a group of normotensive (<140/80 mmHg) subjects diagnosed with T1DM 14 years before. None of them had clinically proven CVD or inflammatory conditions or were on antiplatelet, antihypertensive, anti-inflammatory or lipid-lowering treatment. METHODS: The following information was recorded: sex, age, body-mass index (BMI), waist-to-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), PP, mean blood pressure (MBP), smoking, alcohol intake, insulin dose, lipid profile, HbA1c, microvascular complications, and plasma concentrations of soluble receptor types 1 and 2 of tumour necrosis factor (TNF)-alpha (sTNFR1 and sTNFR2, respectively), interleukin-6, C-reactive protein, adiponectin and leptin. RESULTS: A total of 112 subjects were evaluated (aged 27.4+/-6.6 years, 52.7% women, BMI: 20.4+/-2.7 kg/m2, WHR: 0.82+/-0.09, SBP: 112+/-12 mmHg, DBP: 68+/-9 mmHg, PP: 45+/-9 mmHg, MBP: 82+/-9 mmHg, HbA1c: 8.2% (7.3-9.0%), 41.1% microvascular complications). After adjusting for potential confounders, only inflammatory markers of the TNF-alpha system correlated significantly with PP (Pearson correlation coefficient between sTNFR1 and PP: r = 0.215, P = 0.030; and between PP and sTNFR2: r = 0.238, P = 0.020). CONCLUSION: In normotensive subjects with T1DM after 14 years of diagnosis, the activation of the TNF-alpha system is positively associated with PP levels. This finding might suggest a pathogenic role of the TNF-alpha system in the development of cardiovascular disease in T1DM.

Diabetic neuropathy is associated with activation of the TNF-alpha system in subjects with type 1 diabetes mellitus.

OBJECTIVE: The development of diabetic neuropathy (DN) is predicted by cardiovascular risk factors associated with insulin resistance. As inflammation seems to be implicated in the pathogenesis of insulin resistance, we investigated whether subjects with type 1 diabetes mellitus (T1DM) and DN have an increase in plasma concentrations of inflammatory proteins involved in insulin resistance. DESIGN: Cross-sectional. Patients One hundred twenty subjects, all diagnosed with T1DM 14 years before. MEASUREMENTS: (1) Sex, age, body mass index, waist-to-hip ratio (WHR), blood pressure, smoking, alcohol intake, insulin dose, HbA1c and lipid profile; (2) DN (peripheral and cardiac autonomic), retinopathy and nephropathy; (3) plasma concentrations of soluble fractions of tumour necrosis factor alpha receptors 1 and 2 (sTNFR1 and sTNFR2), interleukin-6, high-sensitive C-reactive protein, adiponectin and leptin; and (4) insulin resistance (by way of a mathematical estimation of the glucose disposal rate - eGDR-). RESULTS: Thirty-six subjects had DN and 84 did not. Subjects with DN received higher insulin doses (57.6 +/- 16.7 vs. 49.2 +/- 15.0 IU/day; P = 0.008) and had higher WHR (0.85 +/- 0.07 vs. 0.81 +/- 0.10; P = 0.007) and HbA1c values (8.5 (7.6-9.6) vs. 7.7 (7.3-8.9)%; P = 0.049) than subjects without DN. They also had higher values of sTNFR1 (2.42 +/- 0.60 vs. 1.96 +/- 0.66 microg/l; P = 0.001) and sTNFR2 (4.73 +/- 1.33 vs. 4.14 +/- 1.09 microg/l; P = 0.015), and were more insulin resistant (eGDR values: 7.28 (5.83-8.03) vs. 8.30 (7.17-9.03) mg kg(-1) min(-1); P = 0.003). The relationship between DN and either sTNFR1 or sTNFR2 remained essentially unchanged after adjusting for several confounders, including glycaemic control, WHR, lipid profile, blood pressure and other microvascular complications (OR for sTNFR1: 2.592 (1.222-5.498), P = 0.013; OR for sTNFR2: 2.124 (1.258-3.587), P = 0.005). CONCLUSIONS: The activity of the TNF-alpha system is increased in subjects with type 1 diabetes mellitus and diabetic neuropathy, regardless of their glycaemic control and cardiovascular risk factors associated with insulin resistance. These results suggest that TNF-alpha may play a pathogenic role in the development of diabetic neuropathy.

Tumour necrosis factor receptors (TNFRs) in Type 2 diabetes. Analysis of soluble plasma fractions and genetic variations of TNFR2 gene in a case-control study.

AIMS: We have studied the relationships between soluble fractions of tumour necrosis factor receptors (sTNFR1 and sTNFR2) in Type 2 diabetes (DM2) and its chronic microvascular complications. Likewise, we have analysed the genetic susceptibility of 196T > G exon6/CA-repeat intron 4 mutations in the TNFR2 gene in this population. METHODS: A case-control study was conducted to examine the role of sTNFRs in 345 DM2 patients and 173 healthy subjects. The mutations were studied in all healthy subjects and in a subset of 232 patients. RESULTS: sTNFRs levels were similar in healthy and DM2 patients. A positive correlation between age and both sTNFRs was observed in healthy subjects. In DM2 patients, sTNFR1 showed a positive correlation with age, systolic blood pressure and leptin levels (r = 0.53, P < 0.0001; r = 0.28, P = 0.005; r = 0.46, P < 0.0001, respectively) and sTNFR2 was positively correlated with age, triglycerides and leptin levels (r = 0.34, P < 0.0001; r = 0.21, P < 0.0001; r = 0.28, P = 0.002, respectively). Patients with micro- or macroalbuminuria showed higher plasma levels of sTNFR1 and sTNFR2 than normoalbuminuric patients, after adjusting for confounding variables (B = 0.85, P = 0.022, 95% CI: 0.12-1.58 for sTNFR1 and B = 1.50, P < 0.001, 95% CI: 0.67-2.33 for sTNFR2). In DM2 patients, TT-exon 6 homozygous showed lower levels of sTNFR1 [2,4 (1.1) vs. 3.4 (1.2) ng/ml], and the CA273-allele tracked with elevated plasma HDL-cholesterol [1.8 (0.7), 1.4 (0.3) and 1.3 (0.3) mm, for CA273/273, CA273/- and CA-/-, respectively]. No association was seen with other analysed variables. CONCLUSIONS: Our findings suggest that chronic TNF activation may have some pathogenic role in diabetic nephropathy in DM2 patients. Genetic variations in exon 6/intron 4 of the TNFR2 gene do not predispose to a major risk for DM2 or its microvascular complications.

Smoking, fat mass and activation of the tumor necrosis factor-alpha pathway.

OBJECTIVE: Obesity may be associated with increased markers of inflammation that could be triggered by metabolic, physical, infectious or environmental processes. As smoking significantly increases cytokine production, we aimed to study how smoking influences the relationship between fat mass and soluble tumor necrosis factor-alpha (TNF-alpha) receptors 1 and 2 (sTNFR1 and sTNFR2). DESIGN: Cross-sectional, clinical observational study. SUBJECTS: A total of 133 healthy men (age: 27-53 y, body mass index (BMI): 24-30.2 kg/m(2)), 80 of whom were never-smokers and 53 smokers, matched for age, BMI and waist-to-hip ratio. MEASUREMENTS: Circulating soluble fractions of the TNF-alpha receptors sTNFR1 and sTNFR2 were measured to study their relationship with fat mass (bioelectric impedance). RESULTS: Smokers had significantly lower fat mass, lower fasting glucose, insulin and leptin concentrations than nonsmokers. Despite lower fat mass and insulin, smokers showed significantly increased circulating sTNFR2 levels (3.7+/-0.8 vs 3.4+/-0.7 ng/ml, P=0.03). The slopes of the relationships between sTNFR1 and fat mass, and between sTNFR2 and fat mass, were significantly steeper in smokers than in nonsmokers. In a stepwise multiple linear regression analysis, both fat mass (P<0.00001) and smoking (P=0.025) independently contributed to 13% of sTNFR1 variance and to 4% of sTNFR2 variance (P=0.03). CONCLUSION: Both fat mass and smoking are related to increased activity of the TNF-alpha axis.

Lower rate of tumor necrosis factor-alpha -863A allele and higher concentration of tumor necrosis factor-alpha receptor 2 in first-degree relatives of subjects with type 2 diabetes.

Allelic variants of the tumor necrosis factor-alpha (TNF-alpha) gene seem to contribute to insulin resistance increasing the transcription rate of TNF-alpha. The TNF-alpha -863A allele is associated with a lower expression of TNF-alpha gene and less secretion of the cytokine. To investigate whether an abnormal TNF-alpha system regulation may contribute to early impairment of insulin action in first-degree relatives of patients with type 2 diabetes mellitus (DM), we studied the TNF-alpha -863C/A polymorphism and the soluble fraction of TNF-alpha receptor-2 (sTNFR2) concentration in these subjects in comparison to a control group. A total of 52% of subjects in the relatives' group showed an abnormal oral glucose tolerance (either as impaired glucose tolerance [IGT] or diabetes) and had more features of the insulin resistance syndrome, despite showing similar body composition as controls. The plasma concentration of the sTNFR2 was higher and insulin sensitivity (%S) was lower in the relatives' group than in the controls. Likewise, the TNF-alpha -863A allele was more commonly detected in the control group (10 of 41) than in the relative's group (2 of 36, P =.029). In a multivariate linear regression analysis, neither TNF-alpha -863A allele nor sTNFR2 independently determined %S. Only body mass index (BMI) and the presence of a positive family history of DM were independent determinants of insulin resistance. In summary, our study showed a lower rate of TNF-alpha -863A allele and higher concentrations of sTNFR2 in first-degree relatives of DM subjects. These findings could be included among the genetic, metabolic, and clinical heterogeneity that characterizes the pathophysiology of DM. The presence of abnormalities in the TNF-alpha pathway could predispose to the development of DM in subjects at risk for the disease.

Bone mineral mass is associated with interleukin 1 receptor autoantigen and TNF-alpha gene polymorphisms in post-menopausal Mediterranean women.

Bone mass is known to be under genetic control. Interleukin-1 (IL-1), interleukin-6 (IL-6) and TNF-alpha are strong inductors of bone resorption. The estrogenic deficiency that occurs during menopause leads to an increase in the production of these cytokines. We analyzed the genetic susceptibility of several polymorphisms of the interleukin-1 receptor antagonist (IL-1ra), IL-6 and TNF-alpha genes in lumbar spine and hip bone mass in a sample of post-menopausal Caucasian Mediterranean women with osteoporosis. 104 post-menopausal osteoporotic women (58.6+/-4.8 yr) and 51 post-menopausal women without osteoporosis as the control group (57.2+/-4.5 yr) were studied. The osteoporotic group was in turn sub-classified into severe and non-severe osteoporosis. The variable number of tandem repeats IL1-ra, IL-6 SfaNI and TNF-alpha NcoI genetic polymorphisms were studied. Biochemical markers of bone turnover were measured in blood and urine. Women carrying the A2 allele (A2+) of the IL-1ra gene showed greater BMD in the lumbar spine (p=0.02) and hip (p=0.006), compared to those not carrying the allele (A2-). The IL-6 polymorphism studied in its 5' flanking region did not show any association with BMD values. The TNF-alpha gene G allele was associated with a greater bone mass in the non-severe osteoporotic subgroup, both in the lumbar spine (p=0.0007) and in the hip (p=0.02). Likewise, genotype combination A2+GG was associated to a greater hip BMD at the femoral neck and Ward triangle levels (p=0.02). We conclude that both IL-1ra and TNF-alpha can be candidate loci to be studied in the susceptibility to develop post-menopausal osteoporosis.

Circulating interleukin 6 levels, blood pressure, and insulin sensitivity in apparently healthy men and women.

There is increasing evidence that systemic inflammation and insulin resistance constitute interrelated events that contribute to atherosclerosis. We studied the effect of the association between circulating interleukin 6 (IL-6) levels, one of the major mediators of inflammation, and C-reactive protein on insulin resistance and blood pressure in 228 healthy volunteers. The plasma IL-6 concentration was significantly and similarly associated with systolic (SBP) and diastolic (DBP) blood pressure, fasting insulin, and the fasting insulin resistance index (FIRI) in all subjects. When smokers were excluded from the analysis, plasma IL-6 levels correlated with percent fat mass (r = 0.19; P = 0.02), absolute fat mass (r = 0.17; P = 0.03), SBP, DBP, fasting insulin levels, and FIRI. The latter associations persisted after controlling for body mass index (r = 0.15 and r = 0.19; P = 0.02 and P: = 0.0004 for SBP and DBP, respectively; r = 0.24 and r = 0.19, P = 0.004 and P = 0.03, for fasting insulin and FIRI, respectively). Gender and smoking status significantly influenced the results. Although IL-6 levels were significantly associated with fasting insulin and FIRI in men, these significant correlations were not observed in women. Conversely, although IL-6 levels were significantly associated with SBP and DBP in women, these coefficients were not statistically significant in men. All of these associations were lost among smokers and remained significant in nonsmokers. As IL-6 is the major mediator of the acute phase response by hepatocytes and induces the synthesis of C-reactive protein (CRP), we also controlled for the latter. Serum CRP levels correlated significantly with IL-6 in all the subjects, but mainly in nonsmokers and men. Of note was that this significant relationship was lost among smokers. CRP was associated with fasting insulin (r = 0.28; P < 0.0001) and FIRI (r = 0.25; P < 0.0001), but not with SBP or DBP (P = NS), in all subjects. Unlike IL-6, the associations between CRP and these parameters were similar in men and women and in smokers and nonsmokers. For insulin and FIRI they were stronger in women and in nonsmokers. CPR significantly correlated with the WHR only in men (r = 0.22; P = 0.01). Using multiple linear regression in a stepwise manner to predict circulating IL-6 levels, smoking status (P = 0.0059) and FIRI (P = 0.03), but not fat mass or SBP, independently contributed to 11% of its variance in men. When CRP was introduced into the model, the latter (P < 0.0001) and smoking status (P = 0.02), but not FIRI, fat mass, or SBP, contributed to 33% of the variance in IL-6 levels. In women, only SBP (P = 0.04) contributed to 5% of its variance. When CRP was introduced into the model, again only SBP (P = 0.01) contributed to 10% of the variance in IL-6 levels. In 25 of these subjects, insulin sensitivity was determined using the frequently sampled iv glucose tolerance test with minimal model analysis, and circulating IL-6 levels were strongly associated with the insulin sensitivity index (r = -0.65; P < 0.0001). Again, this relationship was even stronger in men (r = -0.75; P < 0.001) and was not significant in women (r = -0.26; P = NS). In all of these subjects, only insulin sensitivity (P = 0.0037), not fat mass, contributed to 21% of the variance of IL-6 levels in a multiple linear regression analysis. In summary, circulating IL-6 levels, by inducing either hypertension in women or insulin resistance in men, constitute a significant proatherogenic cytokine. The mechanisms of these associations should be further investigated.