Arterial hypertension diagnosis: A problem?

INTRODUCTION

Arterial hypertension (AHT), a leading risk factor in terms of attributable mortality, is a major public health problem, especially for primary care where most patients are diagnosed and followed up. Correct AHT diagnosis requires adequate theoretical knowledge and technical skills in physicians and nurses. The aim of this study was to evaluate the knowledge and skills used in initial AHT diagnosis by health professionals and to describe the factors that contribute to variability.

METHODOLOGY

Cross-sectional observational study in a sample of 385 primary care physicians and nurses recruited in a Catalan health region. Using a validated questionnaire called ARC, we evaluated theoretical knowledge and analysed factors that may contribute to response variability. We also evaluated practical measurement skills using objective structured clinical examination tests.

RESULTS

Medical and nursing primary care professionals had deficient knowledge and skills for initial AHT diagnosis and measurement, despite self-perceiving their knowledge to be sufficient. However, professionals who had received postgraduate or other AHT training in the previous year scored better in the ARC questionnaire.

CONCLUSIONS

The results of this study point to insufficient AHT expertise to ensure quality clinical practice, suggesting that ongoing theoretical and practical training needs to be improved.

The gut mycobiome composition is linked to carotid atherosclerosis

The mycobiotic component of the microbiota comprises an integral, yet under-researched, part of the gastrointestinal tract. Here, we present a preliminary study of the possible contribution of gut mycobiota to sub-clinical atherosclerosis in a well-characterised group of obese and non-obese subjects in association with the Framingham Risk Score (FRS) and carotid intima-media thickness (cIMT). From all taxa identified, the relative abundance of the phylum Zygomycota, comprising the family Mucoraceae and genus Mucor, was negatively associated with cIMT and this association remained significant after controlling for false discovery rate. Obese subjects with detectable Mucor spp. had a similar cardiovascular risk profile as non-obese subjects. Interestingly, the relative abundance of Mucor racemosus was negatively associated both with FRS and cIMT. Partial least square discriminant analyses modelling, evaluating the potential relevance of gut mycobiota in patients stratified by mean values of cIMT, showed that even a 1 component model had a high accuracy (0.789), with a high R2 value (0.51). Variable importance in projection scores showed that M. racemosus abundance had the same impact in the model as waist-to-hip ratio, high-density lipoprotein-cholesterol, fasting triglycerides or fasting glucose, suggesting that M. racemosus relative abundance in the gut may be a relevant biomarker for cardiovascular risk.

Decreased lipid metabolism but increased FA biosynthesis are coupled with changes in liver microRNAs in obese subjects with NAFLD

BACKGROUND/OBJECTIVE

Many controversies regarding the association of liver miRNAs with obesity and nonalcoholic fatty liver diseases (NAFLD) call for additional validations. This study sought to investigate variations in genes and hepatic miRNAs in a sample of obese patients with or without NAFLD and human hepatocytes (HH).

SUBJECTS/METHODS

A total of 60 non-consecutive obese women following bariatric surgery were recruited. Subjects were classified as NAFLD (n=17), borderline (n=24) and controls (n=19) with normal enzymatic profile, liver histology and ultrasound assessments. Profiling of 744 miRNAs was performed in 8 obese women with no sign of hepatic disease and 11 NAFLD patients. Additional validation and expression of genes related to de novo fatty acid (FA) biosynthesis, uptake, transport and β-oxidation; glucose metabolism, and inflammation was tested in the extended sample. Induction of NAFLD-related genes and miRNAs was examined in HepG2 cells and primary HH treated with palmitic acid (PA), a combination of palmitate and oleic acid, or high glucose, and insulin (HG) mimicking insulin resistance in NAFLD.

RESULTS

In the discovery sample, 14 miRNAs were associated with NAFLD. Analyses in the extended sample confirmed decreased miR-139-5p, miR-30b-5p, miR-122-5p and miR-422a, and increased miR-146b-5p in obese subjects with NAFLD. Multiple linear regression analyses disclosed that NAFLD contributed independently to explain miR-139-5p (P=0.005), miR-30b-5p (P=0.005), miR-122-5p (P=0.021), miR-422a (P=0.007) and miR-146a (P=0.033) expression variance after controlling for confounders. Decreased miR-122-5p in liver was associated with impaired FA usage. Expression of inflammatory and macrophage-related genes was opposite to decreased miR-30b-5p, miR-139-5p and miR-422a, whereas increased miR-146b-5p was associated with FABP4 and decreased glucose metabolism and FA mobilization. In partial agreement, PA (but not HG) led to decreased miR-139-5p, miR-30b-5p, miR-422a and miR-146a in vitro, in parallel with increased lipogenesis and FA transport, decreased glucose metabolism and diminished FA oxidation.

CONCLUSION

This study confirms decreased liver glucose and lipid metabolism but increased FA biosynthesis coupled with changes in five unique miRNAs in obese patients with NAFLD.

Genome-wide DNA methylation pattern in visceral adipose tissue differentiates insulin-resistant from insulin-sensitive obese subjects

Elucidating the potential mechanisms involved in the detrimental effect of excess body weight on insulin action is an important priority in counteracting obesity-associated diseases. The present study aimed to disentangle the epigenetic basis of insulin resistance by performing a genome-wide epigenetic analysis in visceral adipose tissue (VAT) from morbidly obese patients depending on the insulin sensitivity evaluated by the clamp technique. The global human methylome screening performed in VAT from 7 insulin-resistant (IR) and 5 insulin-sensitive (IS) morbidly obese patients (discovery cohort) analyzed using the Infinium HumanMethylation450 BeadChip array identified 982 CpG sites able to perfectly separate the IR and IS samples. The identified sites represented 538 unique genes, 10% of which were diabetes-associated genes. The current work identified novel IR-related genes epigenetically regulated in VAT, such as COL9A1, COL11A2, CD44, MUC4, ADAM2, IGF2BP1, GATA4, TET1, ZNF714, ADCY9, TBX5, and HDACM. The gene with the largest methylation fold-change and mapped by 5 differentially methylated CpG sites located in island/shore and promoter region was ZNF714. This gene presented lower methylation levels in IR than in IS patients in association with increased transcription levels, as further reflected in a validation cohort (n = 24; 11 IR and 13 IS). This study reveals, for the first time, a potential epigenetic regulation involved in the dysregulation of VAT that could predispose patients to insulin resistance and future type 2 diabetes in morbid obesity, providing a potential therapeutic target and biomarkers for counteracting this process.

Are nurses sufficiently well prepared to take on the detection of hypertension?

BACKGROUND

The detection of arterial hypertension requires training and knowledge by the responsible health professional. The current guidelines recommend doctors and nurses to work together for the screening of hypertension.

OBJECTIVES

To assess the level of knowledge among primary healthcare nurses' in the screening of arterial hypertension.

METHODS

Descriptive, observational and transversal study. A random representative sample of 165 nurses working with adult patients in community-based primary healthcare centres were asked to complete an evaluation test of theoretical knowledge about hypertension. Higher scores indicated a greater knowledge about the detection of hypertension.

RESULTS

32.1% of the participants obtained a score equal to or more than 72.7 which corresponded to the 75th percentile of correct answers. Nurses with lower scores were older, permanent employees with technical training studies. A higher age and technical training studies contributed independently to a lower score. In the multiple linear regression model, age and type of studies contributed independently to questionnaire's score variance.

CONCLUSION

Currently, primary care nurses in the studied region do not have sufficient theoretical knowledge to detect hypertension. The results show the need to establish strategies to achieve the necessary knowledge for the implementation of a correct hypertension screening. For professional nurses, continuing education is essential to safe and effective nursing care.

CIDEC/FSP27 and PLIN1 gene expression run in parallel to mitochondrial genes in human adipose tissue, both increasing after weight loss

OBJECTIVE

FSP27 KO mice showed enhanced expression of mitochondrial genes, increased mitochondrial activity and smaller lipid droplets. Here, we aimed to investigate lipid droplet protein (CIDEC/FSP27 and perilipinA (PLIN1)) gene expression in human adipose tissue in association with obesity, insulin resistance and mitochondrial gene expression.

DESIGN AND SUBJECTS

In cohort 1, CIDEC/FSP27, PLIN1, adipogenic (FASN, ACACA, PPARG, GLUT4) and mitochondrial (PPARGC1A, PPARGC1B, TFAM, MT-CO3) gene expression were analyzed in 171 adipose tissue samples (88 visceral adipose tissue (VAT) and 83 subcutaneous adipose tissue (SAT) depots) and in a time course experiment in human subcutaneous and visceral preadipocytes using real-time PCR. In cohort 2, the effects of bariatric surgery-induced weight loss were also evaluated in six caucasian morbidly obese women. Additionally, in cohort 2 FSP27 and PLIN1 protein levels were measured using western blotting.

RESULTS

CIDEC/FSP27 (1.03±0.52 vs 0.49±0.23 relative gene expression unit (R.U.), P<0.0001) and PLIN1 (1.32±0.82 vs 0.63±0.42 R.U., P<0.0001) gene were significantly more expressed in SAT than in VAT. In VAT, CIDEC/FSP27 and PLIN1 gene expression decreased with body mass index, percent fat mass, fasting glucose, fasting insulin, HOMA and were positively associated with adipogenic (PPARG, GLUT4, FASN and ACACA) and mitochondrial biogenesis (PPARGC1A, PPARGC1B, TFAM and MT-CO3)-related genes. Mitochondrial gene expression increased during adipocyte differentiation in parallel to FSP27 and PLIN1 and other adipogenic genes. After bariatric surgery-induced weight loss, PLIN1 and CIDEC/FSP27 gene and protein expression in SAT increased significantly in parallel to adipogenic and mitochondrial genes.

CONCLUSION

These findings suggest a positive functional interaction between CIDEC/FSP27, PLIN1 and mitochondrial biogenesis-related genes in human adipose tissue.

Circulating irisin levels and coronary heart disease: association with future acute coronary syndrome and major adverse cardiovascular events

INTRODUCTION

Irisin is a newly discovered myokine, associated with 'browning' of the white adipose tissue, obesity, insulin resistance and metabolic syndrome. The purpose of this study is to evaluate circulating irisin as a predictor of acute coronary syndromes (ACSs) and major adverse cardiovascular events (MACE).

METHODS

Sub-study 1: a case-control study, nested within the Veteran's Affairs Normative Ageing Study, evaluating circulating irisin levels in 88 ACS cases and 158 age- and sampling year-matched controls, as a predictor of ACS. Sub-study 2: a prospective cohort study, where 103 participants with established coronary artery disease were stratified by circulating irisin levels at the time they received percutaneous coronary interventions (PCIs) and were followed for the development of MACE.

RESULTS

Study 1: there was no association between irisin levels and ACS in otherwise healthy individuals (odds ratio: 1.00 95% confidence interval: (0.99-1.00)). Study 2: the incidence of MACE was significantly lower in the first irisin tertile compared with the second and third (incidence rate 0 vs 0.92 (0.51-1.61) vs 0.57 (0.28-1.14) events per 1000 person-days; P < 0.01). This was primarily driven by the lower incidence of unstable angina (incidence rate 0 vs 0.61 (0.31-1.22) vs 0.43 (0.19-0.96) per 1000 person-days; P = 0.01).

CONCLUSION

This is the first study to date that demonstrates that, although circulating irisin levels do not predict the development of ACS in healthy individuals, increased irisin levels are associated with the development of MACE in patients with established coronary artery disease after PCI.

Circulating lipopolysaccharide-binding protein (LBP) as a marker of obesity-related insulin resistance

OBJECTIVE

Lipopolysaccharide-binding protein (LBP) is a 65-kDa acute-phase protein present in blood at high concentrations, known to be derived from the liver. We aimed to gain insights into the association of circulating LBP with insulin resistance in humans and mice. METHODS, DESIGN AND MEASUREMENTS: We studied the cross-sectional (n=222) and weight loss-induced (n=34) associations of LBP (enzyme-linked immunosorbent assay) with inflammatory and metabolic parameters (including minimal model-measured insulin sensitivity), and the effects of high-fat diet (HFD), metformin and genetic insulin sensitization (glucagon-like peptide 1 receptor knockout model) in mice.

RESULTS

Circulating LBP concentration was significantly increased in subjects with type 2 diabetes and dramatically increased in subjects with morbid obesity. LBP was significantly associated with insulin sensitivity and different inflammatory markers and decreased after weight loss (22.2 ± 5.8 vs 16.2 ± 9.3 μg ml(-1), P<0.0001) in association with changes in body mass index and insulin sensitivity. Circulating LBP concentration was increased in HFD mice, whereas decreased in glucagon-like peptide 1 receptor knockout mice (significantly more insulin sensitive than wild-type mice) and after metformin administration.

CONCLUSION

LBP is an inflammatory marker associated with obesity-related insulin resistance.

Decreased serum creatinine concentration is associated with short telomeres of adipose tissue cells

Decreased serum creatinine concentration has been recently described to constitute a new risk factor of type 2 diabetes. Increased free radicals have been consistently associated with decreased serum creatinine and with cellular senescence. Telomere length is considered as a biological marker for senescence. We aimed to study the association of telomere length with serum creatinine. Telomere length of subcutaneous adipose tissue cells was measured in a sample of obese and nonobese subjects (n = 49). Telomere length of subcutaneous adipose tissue cells was positively associated with serum creatinine (r = 0.40, P = 0.004), i.e., the lower the telomere length, the lower the serum creatinine, but not with glomerular filtration rate (GFR). In addition, telomere length was negatively associated with BMI (r = -0.45, P = 0.001) and systolic blood pressure (r = -0.41, P = 0.003). In a multiple linear regression analysis, BMI (P = 0.005), systolic blood pressure (P = 0.01) and telomere length (P = 0.03) independently contributed to 37% of serum creatinine variance after controlling for sex and age. In conclusion, the association of serum creatinine with a marker of cellular senescence suggests an underlying mechanism influencing both decreased serum creatinine and increased risk of type 2 diabetes.

Circulating osteocalcin concentrations are associated with parameters of liver fat infiltration and increase in parallel to decreased liver enzymes after weight loss

SUMMARY

The expression of liver genes was associated with insulin action in osteocalcin knockout mice. Our findings suggest that osteocalcin may play a role in the development of insulin resistance-associated fatty liver disease.

INTRODUCTION

The expression of insulin target genes was decreased in the liver of mice lacking osteocalcin. We aimed to explore the association of liver enzymes with osteocalcin.

METHODS

The associations were evaluated in a cross-sectional study (266 men) and following weight loss in 28 obese subjects (nine male, 19 females).

RESULTS

In the cross-sectional study, circulating osteocalcin concentration was negatively associated with alanine transaminase (ALT) (p = 0.002) and aspartate transaminase (AST) levels (p = 0.008). These associations were especially significant in non-obese subjects (n = 191). In a multiple linear regression analysis, age (p = 0.008), insulin sensitivity (p = 0.001), and osteocalcin (p = 0.04) independently contributed to 22% of ALT variance in these latter subjects. In the weight loss study, the increase in circulating osteocalcin concentration (+70.6 ± 29.3 vs. +32 ± 13.5%, p = 0.021) was significantly greater in subjects with the highest decrease in ALT levels, despite similar baseline BMI, insulin resistance and degree of weight loss than remaining subjects. In fact, the change in ALT levels were linearly associated with those of osteocalcin (r = -0.55, p = 0.003).

CONCLUSIONS

In summary, our findings suggest a bone-liver axis in which osteocalcin might be the active regulator.

[Insulin resistance as a mechanism of adaptation during human evolution]

The recent application of concepts of evolution to human disease is proving useful to understand certain pathophysiological mechanisms of different entities that span genomic alterations of immunity, respiratory and hormone function, and the circulatory and neural systems. However, effort has concentrated on explaining the keys to adaptation that define human metabolism and, since the early 1960s, several theories have been developed. This article reviews some of the hypotheses postulated in recent years on the potential benefit of insulin resistance and discusses the most recent knowledge. The concept of the thrifty gene seems to have been definitively refuted by current knowledge. The current paradigm describes an interaction between the metabolic and the immune systems resulting from their coevolution, promoted by evolutionary pressures triggered by fasting, infection and intake of different foods. The activation and regulation of these ancient mechanisms in integrated and interdependent areas defines insulin resistance as a survival strategy that is critical during fasting and in the fight against infection. The relationship with some components of the diet and, particularly, with the symbiotic intestinal microflora points to new paradigms in understanding the pathophysiology of obesity, metabolic syndrome and type 2 diabetes mellitus.

Thyroid hormone responsive Spot 14 increases during differentiation of human adipocytes and its expression is down-regulated in obese subjects

CONTEXT

Very limited information is available regarding the function of human thyroid hormone responsive Spot 14 (human S14, hS14) in adipogenesis and human adiposity.

OBJECTIVE

To evaluate hS14 levels during differentiation of human pre-adipocytes, in human fat depots and isolated fat cells.

DESIGN

This was a cross-sectional study.

SUBJECTS

A total of 161 omental (OM) and 87 subcutaneous (SC) adipose tissue samples obtained during elective surgical procedures from a population who varied widely in terms of obesity.

MEASUREMENTS

hS14 gene expression and protein levels during adipogenesis were assessed by RT-PCR, western blot, and using an automated confocal imaging approach.

RESULTS

hS14 gene expression levels were decreased in OM adipose tissue from overweight (-42.0%) and obese subjects (-56.5%) compared with lean subjects (P<0.05 and P<0.0001, respectively). hS14 mRNA (but not hS14-related) was inversely associated with obesity measures such as body mass index (P=0.001), percent fat mass (P=0.001), waist-to-hip ratio (P=0.020), and systolic blood pressure (P=0.031). hS14 gene expression and protein levels were up-regulated at the early stages of differentiation of human pre-adipocytes as well as for 3T3-L1 cells. That observation was most prominent in those individual cells exhibiting the more marked differentiation features. hS14 gene expression levels increased by approximately 45 000-fold in mature adipocytes. Increased hS14 levels were also found in stromal-vascular cells/pre-adipocytes (3.8-fold, P<0.05) and in adipose tissue samples (1.9-fold, P<0.0001) from SC compared with OM fat depots.

CONCLUSIONS

These results suggest that hS14 is involved in human adipogenesis, but inversely related to obesity and OM fat accumulation.

Decreased circulating lactoferrin in insulin resistance and altered glucose tolerance as a possible marker of neutrophil dysfunction in type 2 diabetes

CONTEXT

Lactoferrin is an innate immune system protein with multiple beneficial health activities.

OBJECTIVE

To gain insight in the interaction between innate immune system and metabolic disturbances (obesity and insulin resistance), we investigated the relationship between circulating lactoferrin and chronic inflammation-associated insulin resistance according glucose tolerance status in Caucasian population.

DESIGN, SETTING, PARTICIPANTS, AND MAIN OUTCOME MEASURES

Circulating nonstressed lactoferrin (ELISA), metabolic variables, and inflammatory markers were measured in 229 men, 94 with normal (NGT) and 135 with altered glucose tolerance (AGT). Lactoferrin secretion by neutrophil was investigated in whole-blood culture (four young NGT subjects, four older NGT subjects, and four patients with type 2 diabetes) under microbial lipopolysaccharide (LPS) with IL-6 and rosiglitazone treatment. We also tested the lactoferrin action in THP-1 cells under LPS stimulus.

RESULTS

Circulating lactoferrin was significantly decreased in patients with AGT (431.5 +/- 187.5 vs. 493.5 +/- 238.9 ng/ml, P = 0.02). In addition, circulating lactoferrin was negatively associated with hyperglycemia and obesity measures and positively with insulin sensitivity. Lactoferrin was negatively related to inflammatory markers, especially in AGT subjects. In ex vivo experiments, we found a significant decrease in LPS-induced lactoferrin release from neutrophils in subjects with type 2 diabetes. IL-6 coincubation decreased LPS-induced lactoferrin release in NGT subjects (P < 0.001). Finally, rosiglitazone treatment led to increased lactoferrin secretion (398 +/- 193 vs. 280.1 +/- 104.9 ng/ml, P < 0.0001). Lactoferrin decreased nuclear factor-kappabeta activation and IL-6, IL-8, and macrophage chemoattractant protein-1 expression under LPS challenge.

CONCLUSIONS

Decreased circulating lactoferrin levels may play a role in chronic low level inflammation-associated insulin resistance.

Gender dimorphism in body composition abnormalities in acromegaly: males are more affected than females

BACKGROUND

Acromegaly changes body composition (BC), but long-term gender differences have not been reported.

OBJECTIVE

To evaluate BC in active and controlled acromegalic patients.

DESIGN AND METHODS

Clinical and biochemical variables and BC (by dual-energy X-ray absorptiometry) were evaluated in 60 acromegalic patients (19 active, 41 controlled) and 105 controls, matched for age and gender.

RESULTS

Acromegalic males (n=24) had more total mass (89+/-13 vs 76.5+/-15.3 kg, P<0.001), lean body mass (LBM; 64.6+/-8.7 vs 56.4+/-5.8 kg, P<0.001), and bone mineral content (BMC; 2.9+/-0.5 vs 2.6+/-0.3 kg, P<0.05) than controls (n=33). Controlled male patients (n=14) had more total mass (89+/-14.7 vs 76.5+/-15.3 kg, P<0.05) and a trend to have more LBM (61.8+/-9.4 vs 56.4+/-5.8 kg, P=0.065) than controls. Only in active disease was a decrease in fat mass (FM) observed, compared with controlled patients and controls (males: 19.5+/-5.3 vs 27+/-6.2 and 25.9+/-4%, P<0.001; females: 30.3+/-6.7 vs 37.1+/-5.8 and 36.5+/-6.6%, P<0.01). In females, no further differences were observed. No differences in BMC were found between eugonadal and hypogonadal acromegalic patients, but in hypogonadal females, acromegaly appeared to prevent the BMC loss seen in hypogonadal postmenopausal controls. GH and IGF1 levels were negatively correlated with FM (males, P<0.05; females, P<0.001), but in the regression analysis GH was a predictor of FM only in women.

CONCLUSIONS

Control of acromegaly reverts decreased FM in both genders; only in males more total mass and a trend for more LBM persist. The anabolic effect of GH on bone reverted in cured males, but persisted in females and appeared to override the bone loss of menopause.

Maternal glucose tolerance status influences the risk of macrosomia in male but not in female fetuses

OBJECTIVE

To elucidate whether the risk of macrosomia, large for gestational age (LGA) and small for gestational age (SGA) is influenced by maternal body mass index and glucose tolerance differently in male and female fetuses.

METHODS

A population study was conducted in 16 general hospitals from the Spanish National Health Service that included 9270 consecutive women with singleton pregnancies and without a former diagnosis of diabetes mellitus who delivered 4793 male and 4477 female newborns. Logistic regression analyses were performed to predict the effect of body mass index (BMI) category and glucose tolerance on macrosomia, large for gestational age newborns (LGA) and small for gestational age newborns (SGA) Separate analyses according to foetal sex were carried out for each outcome. The results were adjusted for maternal age, gestational age and pregnancy-induced hypertension.

RESULTS

There were significant differences between males and females in the percentage of infants who had macrosomia, LGA or SGA. Maternal BMI category was positively associated with the risk of macrosomia and LGA in both male and female newborns. In addition, there was a negative association between maternal BMI and SGA that only reached significance in males. In contrast, gestational diabetes was only a predictor of macrosomia exclusively in male fetuses (OR 1.67, 95% CI 1.12 to 2.49)

CONCLUSIONS

There is sexual dimorphism in the risk of abnormal birth weight attributed to maternal glucose tolerance status. A closer surveillance of foetal growth might be warranted in pregnant women with abnormal glucose tolerance carrying a male fetus.

Cost of severe hypoglycaemia in patients with type 1 diabetes in Spain and the cost-effectiveness of insulin lispro compared with regular human insulin in preventing severe hypoglycaemia

OBJECTIVES

To determine the costs of severe hypoglycaemia (SH) in a population of patients with type 1 diabetes mellitus in the Spanish healthcare system and the cost-effectiveness of insulin lispro over regular insulin in preventing SH episodes.

METHODS

A retrospective study of 100 patients in three Spanish health centres was performed. Resource utilisation data were collected only for interventions specifically relating to the hypoglycaemic episode. The direct medical costs determined in the analyses were: costs of hospitalisation, diagnostic tests carried out, costs of treatment administered and other associated costs such as visits to the endocrinologist and re-training in glucose control, transportation and assistance of a care-giver. In addition, indirect costs such as days of lost productivity were measured. The incidence rates of SH for insulin lispro and regular insulin were obtained from the literature. The incremental cost-effectiveness of insulin lispro over regular insulin was calculated.

RESULTS

The overall mean cost per episode of SH was 366 euro, comprised of 65.4% direct costs and 35.6% indirect costs. The largest cost was for hospitalisation at 183 euro per episode. The SH episodes incidence rates for 100 patients per year were 33 and 73 for insulin lispro and 48 (p < 0.05) and 117 (p < 0.01) for regular insulin, in the two clinical trials found in the literature. The additional cost to prevent one episode of SH with insulin lispro over regular insulin ranged from 277 euro to insulin lispro dominance.

CONCLUSIONS

Severe hypoglycaemia has a significant impact on the total cost of diabetes. The use of insulin lispro is associated with reductions in annual costs because of SH and, possibly, the overall effect may be cost neutral or cost saving when total costs are considered. The cost of SH should be included in the analysis of total socio-economic burden of diabetes.

Critical assessment of the current guidelines for the management and treatment of morbidly obese patients

An interdisciplinary panel of specialists met in Mallorca in the first European Symposium on Morbid Obesity entitled; "Morbid Obesity, an Interdisciplinary Approach". During the two and half days of the meeting, the participants discussed several aspects related to pathogenesis, evaluation, and treatment of morbid obesity. The expert panel included basic research scientists, dietitians and nutritionists, exercise physiologists, endocrinologists, psychiatrists, cardiologists, pneumonologists, anesthesiologists, and bariatric surgeons with expertise in the different weight loss surgeries. The symposium was sponsored by the Balearic Islands Health Department; however, this statement is an independent report of the panel and is not a policy statement of any of the sponsors or endorsers of the Symposium. The prevalence of morbid obesity, the most severe state of the disease, has become epidemic. The current recommendations for the therapy of the morbidly obese comes as a result of a National Institutes of Health (NIH) Consensus Conference held in 1991 and subsequently reviewed in 2004 by the American Society for Bariatric Surgery. This document reviews the work-up evaluation of the morbidly obese patient, the current status of the indications for bariatric surgery and which type of procedure should be recommended; it also brings up for discussion some important real-life clinical practice issues, which should be taken into consideration when evaluating and treating morbidly obese patients. Finally, it also goes through current scientific evidence supporting the potential effectiveness of medical therapy as treatment of patients with morbid obesity.

Asymptomatic bilateral adrenal pheochromocytoma in a patient with a germline V804M mutation in the RET proto-oncogene

A diagnosis of bilateral pheochromocytoma warrants exclusion of hereditary pheochromocytoma.

OBJECTIVE

To describe the first case of a bilateral pheochromocytoma associated with V804M mutation in the RET proto-oncogene.

PATIENTS

The index case was a 54-year-old man with bilateral adrenal masses discovered during a CT scan performed for other reasons.

MEASUREMENTS

Genetic analysis included exons 8-11 and 13-17 in the RET proto-oncogene, all four exons and flanking intronic regions in the SDHD gene, all eight exons and flanking intronic regions in the SDHB, and all three exons in the VHL gene.

RESULTS

Investigations revealed elevated urinary metanephrines (32.3 micromol/day), and laparoscopic bilateral adrenalectomy confirmed bilateral pheochromocytomas. A heterozygous V804M mutation in exon 14 of the RET was found in the index case and in four relatives. Total thyroidectomy, performed in four of five affected members in this kindred, disclosed a medullary thyroid carcinoma in the index case and in a 50-year-old woman, and nodular C-cell hyperplasia in the other two subjects.

CONCLUSIONS

This clinical case suggests that individuals carrying the germline V804M mutation should be screened annually for the presence of pheochromocytoma.

Protection from inflammatory disease in insulin resistance: the role of mannan-binding lectin

AIMS/HYPOTHESIS

Decreased sensing of the innate immune system may lead to chronic activation of the inflammatory cascade. We hypothesised that mannan-binding lectin (MBL) deficiency may confer risk of obesity and insulin resistance.

MATERIALS AND METHODS

We performed a cross-sectional study of MBL protein concentration (n=434) and MBL2 gene mutations (exon 1) (n=759) in association with obesity, markers of inflammation and insulin action (euglycaemic clamp, n=113), and a longitudinal study of MBL protein before and after weight loss in obese patients (n=10). We also studied the effects of MBL in vitro in muscle cells and circulating MBL-A (mouse equivalent of human MBL) in a mouse model.

RESULTS

Among 434 consecutive non-diabetic men, the age-adjusted serum MBL concentration was lower in obese subjects than in lean subjects (median: 959 microg/ml [interquartile range: 116.8-2,044 microg/ml] vs 1,365 [467-2,513] microg/ml; p=0.01) and was accompanied by increased serum inflammatory markers. Insulin action correlated significantly with serum MBL (r=0.49, p<0.0001). Serum MBL concentration increased by a median of 110.2% after weight loss. The change in serum concentration of MBL was positively associated with the increase in insulin sensitivity (r=0.713, p=0.021). At least one MBL2 gene mutation was present in 48.2% of obese vs 39.3% of non-obese subjects (p=0.037). The plasma concentration of MBL-A was lower in insulin-resistant obese ob/ob mice, as was the glucose/insulin ratio. Incubation of rat soleus muscle with human MBL markedly increased fatty acid oxidation.

CONCLUSIONS/INTERPRETATION

These findings suggest that MBL, previously thought only to be involved in inflammation and immune system function, affects metabolic pathways.

Circulating IL-18 concentration is associated with insulin sensitivity and glucose tolerance through increased fat-free mass

AIMS/HYPOTHESIS

Knowledge of the factors which simultaneously contribute to insulin-resistance-related inflammation may contribute to early therapeutic targeting. IL-18 has recently been described as one of the factors which, in addition to insulin resistance, may also contribute to atherosclerosis. However, the source of IL-18 is not well characterised.

MATERIALS AND METHODS

We aimed to study body composition (bioelectric impedance), glucose tolerance (OGTT) and insulin sensitivity (minimal model method) in relation to serum IL-18 (ELISA) concentration in 144 otherwise healthy men aged 51.9+/-12.5 years.

RESULTS

In contrast to previous observations in women, circulating IL-18 was not significantly associated with BMI (r=0.12, p=0.1) or WHR (r=0.08, p=0.3). IL-18 was also not associated with absolute or percent fat mass (bioelectric impedance, p>0.20) but, interestingly, it was significantly linked to fat-free mass (p=0.03). Serum IL-18 increased with each quartile of fat-free mass, corresponding to values of < or = 64.2; >64.2 to < or = 71.6; >71.6 to < or = 80.9; and > or = 80.9 kg (ANOVA, p<0.0001). IL-18 was more closely associated with postload glucose during an OGTT (p=0.04) rather than with fasting glucose (p=0.1). HbA1c (p=0.03), HDL-cholesterol (p=0.04) and serum triglycerides (p=0.03) and parameters of systemic inflammation (C-reactive protein, p=0.02) were also significantly associated with circulating IL-18. Insulin sensitivity (minimal model analysis) was linked to circulating IL-18 (p=0.01). In a multiple linear regression analysis this relationship remained significant after controlling for BMI, age and glucose tolerance status. In another model, both fat-free mass and insulin sensitivity contributed to 10% of IL-18 variance.

CONCLUSIONS/INTERPRETATION

Fat mass does not seem to influence circulating IL-18, as initially proposed. In contrast, the fat-free mass compartment (a well-known confounder in the evaluation of insulin sensitivity) may significantly contribute to the relationship between IL-18 and insulin action.

Body mass index has a greater impact on pregnancy outcomes than gestational hyperglycaemia

AIMS/HYPOTHESIS

We evaluated diabetes-related pregnancy outcomes in a cohort of Spanish women in relation to their glucose tolerance status, prepregnancy BMI and other predictive variables.

METHODS

The present paper is part of a prospective study to evaluate the impact of American Diabetes Association (2000) criteria in the Spanish population. A total of 9,270 pregnant women were studied and categorised as follows according to prepregnancy BMI quartiles and glucose tolerance status: (1) negative screenees; (2) false-positive screenees; (3) gestational diabetes mellitus (GDM) according to American Diabetes Association criteria only; and (4) GDM according to National Diabetes Data Group criteria (NDDG). We evaluated fetal macrosomia, Caesarean section and seven secondary outcomes as diabetes-related pregnancy outcomes. The population-attributable and population-prevented fractions of predictor variables were calculated after binary logistic regression analysis with multiple predictors.

RESULTS

Both prepregnancy BMI and abnormal glucose tolerance categories were independent predictors of pregnancy outcomes. The upper quartile of BMI accounted for 23% of macrosomia, 9.4% of Caesarean section, 50% of pregnancy-induced hypertension and 17.6% of large-for-gestational-age newborns. In contrast, NDDG GDM accounted for 3.8% of macrosomia, 9.1% of pregnancy-induced hypertension and 3.4% of preterm births.

CONCLUSIONS/INTERPRETATION

In terms of population impact, prepregnancy maternal BMI exhibits a much stronger influence than abnormal blood glucose tolerance on macrosomia, Caesarean section, pregnancy-induced hypertension and large-for-gestational-age newborns.

Potential impact of American Diabetes Association (2000) criteria for diagnosis of gestational diabetes mellitus in Spain

AIMS/HYPOTHESIS

This study was carried out to determine the impact of American Diabetes Association (ADA) 2000 criteria for the diagnosis of gestational diabetes mellitus (GDM) in the Spanish population.

METHODS

Pregnant women were assigned to one of four categories: negative screenees, false-positive screenees, ADA-only-GDM (untreated) and GDM according to National Diabetes Data Group (NDDG) criteria (treated). Fetal macrosomia and Caesarean section were defined as primary outcomes, with seven additional secondary outcomes.

RESULTS

Of 9,270 pregnant women screened for GDM, 819 (8.8%) met NDDG criteria. If the threshold for defining GDM had been lowered to ADA criteria, an additional 2.8% of women would have been defined as having the condition (relative increase of 31.8%). Maternal characteristics of women with ADA-only-GDM were between those of false-positive screenees and women with NDDG-GDM. The risk of diabetes-associated complications was slightly elevated in the individuals who would have been classified as abnormal only after the adoption of ADA criteria. In addition, the ADA-only-GDM contribution to morbidity was lower than that of other variables, especially BMI.

CONCLUSIONS/INTERPRETATION

Use of the ADA criteria to identify GDM would result in a 31.8% increase in prevalence compared with NDDG criteria. However, as the contribution of these additionally diagnosed cases to adverse GDM outcomes is not substantial, a change in diagnostic criteria is not warranted in our setting.

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.

[Prevalence of diabetic retinopathy in the region of Girona. Study of related factors]

PURPOSE

To determine of the prevalence of diabetic retinopathy in the general diabetic population in the Girona region and epidemiologic study of the related factors.

METHODS

A population-based cross-sectional study of a randomised sample taken of 401 diabetics in the Girona region. Descriptive statistical analysis of the ocular lesions in relation to diabetic retinopathy and analysis of logistic regression in order to determine the related factors.

RESULTS

30.6% (IC 95%: 26.5-35.5) of the sample presented some degree of diabetic retinopathy, 19.4% (IC 95%: 15.4-24.0) at the initial stage, 8.4% (IC 95%: 5.8-1.9) pre-proliferative and 2.6% (IC 95%: 1.3-5.1) at a proliferative stage. Regarding the type of diabetes, 53% of the patients with type 1 diabetes and 34.2% of those with type 2 diabetes had retinopathy. Retinopathy was observed in 15.7% of diabetics with less than 10 years of diabetes evolution, 51.3% in those between 10 and 20 years and 62.8% in those with more than 20 years. The concentration of HbA1C was significantly associated with the degree of retinopathy. Of those patients with retinopathy, 60.3% were insulin-treated, 30.6% with oral hypoglucemiants and 10.3% on diet only. Patients with family antecedents of retinopathy presented a prevalence three times greater than those without.

CONCLUSIONS

Approximately one in three diabetic patients exhibited some degree of retinopathy in this study dealing with a population-based cohort of diabetic patients in Spain. The prevalence was greater among type I diabetic patients. As expected, years of evolution of the disease, type of treatment and diabetic metabolic control were the most significant factors influencing the presence of retinopathy.

Maternal soluble tumour necrosis factor receptor type 2 (sTNFR2) and adiponectin are both related to blood pressure during gestation and infant's birthweight

OBJECTIVE

Tumour necrosis factor alpha (TNF-alpha) and adiponectin are strongly related to insulin sensitivity; insulin resistance of pregnancy is a major determinant of infant's birthweight. We aimed to study the contributions of maternal serum concentrations of soluble TNF-alpha receptors (sTNFR1 and sTNFR2) and adiponectin to infant's birthweight.

DESIGN

Cross-sectional, hospital-based study of insulin sensitivity during gestation.

PATIENTS

Fifty-one healthy women with uncomplicated pregnancy and delivery (except for elective Caesarian section) and their healthy newborn infants. measurements Maternal blood levels of glucose, insulin, glycosylated haemaglobin (HbA1c), sTNFR1, sTNFR2 and adiponectin at delivery; cord-blood levels of sTNFR1, sTNFR2 and adiponectin.

RESULTS

At delivery, maternal sTNFR2 correlated with systolic blood pressure (SBP; r = 0.38, P = 0.005). In multiple regression analyses, SBP and HbA1c were independent predictors of sTNFR2, explaining 18 and 7% of its variance, respectively; insulin resistance index (HOMA-IR), body mass index at delivery and SBP were independent predictors of adiponectin, explaining 15, 8 and 7% of its variance, respectively. Both maternal sTNFR2 and SBP were negatively correlated with infant's birthweight (r = -0.28, P = 0.04 and r = -0.36, P = 0.01 respectively, adjusted for sex and gestational age). In multivariate regression analyses, infant's sex and either maternal sTNFR2 or adiponectin were independent predictors of infant's birthweight, each explaining between 6 and 9% of birthweight variance. Further addition of maternal SBP to these models revealed that this variable was the main predictor of infant's birthweight, explaining 13% of its variance.

CONCLUSIONS

Maternal sTNFR2 and adiponectin are independently related to both maternal blood pressure and infant's birthweight in uncomplicated pregnancy. The contributions of the TNF-alpha system and adiponectin to hypertensive disorders of pregnancy and fetal growth merit further studies.

[Obesity and inflammation]

The adipose tissue produces a vast number of molecules called adipokines such as leptin, tumoral necrosis factor (TNFalpha), interleukins and adiponectin. Many of the metabolic disturbances associated with obesity and the metabolic syndrome may be due to citokine production by adipocytes. The adipose tissue increases the soluble fractions of TNFalpha leading to a rise in its biological activity. The activation of TNFalpha system causes insulin resistance through different mechanisms such as defects in receptor fosforilation and reduction in insulin-sensitive glucose transporters. TNFalpha is also involved in the pathophysiology of hypertension and dyslipidaemia associated with obesity and insulin resistance. More than one third of interleukin-6 (IL-6) concentrations come from the adipocytes. It has been demonstrated a role for IL-6 in the development of hyperlipidemia, diabetes and hypertension. In contrast to the rest of adipokines, adiponectin is reduced in obesity, diabetes or cardiovascular disease. Adiponectin improves insulin resistance, dyslipidaemia and adhesion to endothelial cells protecting from atherosclerosis development. Thus, adipokines have an important role in the pathophysiology of metabolic syndrome by different mechanisms involving metabolic and vascular effects.

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.

[Ponderal evolution in the Girona population, 1989-1999]

BACKGROUND AND OBJECTIVE

Despite the number of plans leading to lose weight among individuals in the developed countries, the prevalence of obesity has increased since 1980. The knowledge of ponderal evolution in a given population is very important because the adverse effects of obesity vary greatly among individuals and populations. The objective of the present paper was to determine the modifications in the different degrees of body adiposity in a population in Catalunya.

PATIENTS AND METHODS

A measurement was made of weight and height of 24554 users aged over 14 years (10595 males and 13959 females) attended at four basic health areas (BHA): Girona 1, Girona 4, Salt and Camprodon, and a Primary Health Center (PHC) in the Girona province, for a five-year period, 1995-1999. The prevalence of the different degrees of obesity was compared with that obtained in a previous study with 6373 individuals during the 1986-1989 period (4,579 males and 1794 females).

RESULTS

The prevalence of women with overweight (defined as a body mass index [BMI] > 25 kg/m2) increased from 7.3% (1986-1989, study 0) to 17.6% (1995-1999, study 1) for women aged 15 to 24 years ( p < 0.001), from 17.9 % to 28.1% for women aged 25 to 34 years (p < 0.001), and from 37.5% to 44.7 % for women aged 35 to 44 years (p < 0.001). In the latter age group, the proportion of women with obesity (BMI > 30 kg/m2) increased from 6.9% to 12.9%. Similar trends were observed among men, and the change in the 35-44 year age group (from 10.5 % of obese men to 16% [p < 0.001]), and 55 to 65 years (from 16.6% of obese men to 22.7% [p < 0.001] was particularly significant. And lastly, it is also noteworthy the proportion of individuals with low weight (BMI < 18.5 kg/m2) which increased from 7.3% to 11.6% for women aged 15 to 24 years, and from 0.3% to 2.2% for women aged 35 to 44 years. This trend was also observed for men aged 15 to 24 years (11% to 17.2%).

CONCLUSIONS

The relative increase in the prevalence of overweight and obesity runs in parallel to that found in other surrounding countries. Also, it is worth mentioning that among women aged 15 to 24 years the increase in the prevalence of low weight and obesity is almost identical, which invalidates the mean and median values as a means to assess the ponderal evolution in this population. The current compartmentalization between the extreme BMIs, particularly among the youngest portion of population should be addressed from a multidisciplinary perspective.

Short-term mortality of myocardial infarction patients with diabetes or hyperglycaemia during admission

AIM

The hypothesis that patients with hyperglycaemia during admission, regardless of previous diagnosis of diabetes, have worse prognosis than those with normal glucose values is controversial. The objective was to assess the role of hyperglycaemia on short-term mortality after myocardial infarction (MI).

METHODS AND RESULTS

A cohort study nested in a prospective registry of MI patients in the reference hospital of Gerona, Spain was performed. All consecutive MI patients under 75 were registered between 1993 and 1996. Patient and clinical characteristics, including previous diagnosis of diabetes, glycaemia on admission and in the next four days, were recorded. Patients with glycaemia on admission or four day mean glycaemia >6.67 mmol/l were considered hyperglycaemic. The main outcome measure was mortality at 28 days. Of 662 patients with MI included, 195 (29.7%) had previously known diabetes mellitus, but 457 (69.0%) had glycaemia >6.67 mmol/l on admission. Patients with hyperglycaemia on admission were older, more often female, more frequently had a previous diagnosis of diabetes, developed more complications, and had higher 28 day mortality. The effect of admission glycaemia >6.67 mmol/l on 28 day mortality was independent of major confounding factors, particularly previous diagnosis of diabetes (OR=4.20, 95% confidence intervals 1.18 to 14.96).

CONCLUSIONS

Higher 28 day mortality was observed among MI patients with glycaemia on admission >6.67 mmol/l compared with patients with lower levels, independently of major confounding variables and, particularly, previous diagnosis of diabetes. This early, simple, and inexpensive marker of bad prognosis after MI should prompt the application of more aggressive treatment of MI and risk factors and, probably, of glycaemia during admission.

Circulating granulocyte-macrophage colony-stimulating factor and serum fatty acid composition in men and women

Atherosclerosis is increasingly recognized as an inflammatory disease. Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a proinflammatory cytokine, recently implicated as a prominent component of the regulatory network involved in atherogenesis. We aimed to study the relationship between circulating GM-CSF levels and serum fatty acid (FA) composition in 78 healthy subjects. The latter was analyzed by gas-liquid chromatography and GM-CSF by a high-sensitivity commercial enzyme-linked immunosorbent assay (ELISA). Among women (n = 40), serum GM-CSF levels were found to be positively associated with the proportion of palmitic acid (C16:0) and negatively with linoleic acid (C18:2omega-6), docosahexaenoic acid (DHA, C22:6omega-3), and the proportion of total essential FA. After excluding smoking women (n = 6), the associations among GM-CSF and serum linoleic acid concentration (r = -0.49, P =.003), arachidonic acid (r = -0.52, P =.001), and DHA (r = -0.34, P =.04) were strengthened. The ratio of palmitic to linoleic and DHA acids was the single best predictor of serum GM-CSF in all subjects. Together with arachidonic acid, it contributed to 22% of the GM-CSF variance in women, after taking into account the effects of age, body mass index (BMI), blood pressure, and smoking status. None of these associations were observed among men. In conclusion, serum FA composition is associated with circulating GM-CSF specifically in women. As human arterial and venous smooth muscle cells release GM-CSF, and treatment of endothelial cells with oxidized low-density lipoproteins results in a rapid expression of GM-CSF, the mechanisms involved in these associations and the sex-linked differences should be further explored.

[Body mass index (BMI) and percent fat mass. A BMI > 27.5 kg/m2 could be indicative of obesity in the Spanish population]

BACKGROUND

The World Health Organization (WHO) defines obesity as a condition of excessive fat accumulation to the extent that health and well-being are affected. For population studies, the measurement of weight, corrected for height, is still the method of choice (BMI). In Caucasian populations, the BMI cut-off point for obesity (30 kg/m2) corresponds with a percent body fat (PFM) of over 25% in young adult males and 35% in young adult females. However, the relation between BMI and PFM is not uniform among populations. It is important to define in each population the threshold of BMI which corresponds to the definition of obesity.

PATIENTS AND METHOD

BMI was calculated in 282 subjects. PFM was analyzed using Bio-electrical impedance. Blood pressure, serum glucose and insulin, and the fasting insulin resistance index were also determined in all subjects to analyze the metabolic impact.

RESULTS

The PFM of 25% in males and 35% in females corresponded to a BMI of 27.5 and 27.4 kg/m2, respectively. The slope of the relationship between the degree of obesity and comorbilities (insulinemia, fasting insulin resistance index and blood pressure) was strengthened above 26 kg/m2 in men and 24 kg/m2 in women.

CONCLUSIONS

BMI that corresponds to a PFM previously defined as obesity is lower in our population in comparison with other Caucasian populations. Our results confirm that is impossible to compare the prevalence of obesity among populations using exclusively the BMI. It will be important to define, using reference methods, whether these findings have physiological impact or not, and if this cut-off of BMI determines an increment in cardiovascular and overall mortality using epidemiological approaches.

Study of the effect of changing glucose, insulin, and insulin-like growth factor-I levels on serum corticosteroid binding globulin in lean, obese, and obese subjects with glucose intolerance

We have previously described that serum corticosteroid binding globulin (CBG) concentrations are associated with insulin secretion. The present study was designed to evaluate the effects of changing insulin concentrations, both endogenous and after exogenous insulin administration, on circulating CBG levels in vivo. Serum CBG concentrations were measured during an insulin-modified frequently sampled intravenous (IV) glucose tolerance test (FSIVGT) in 14 lean and 19 obese otherwise healthy subjects with varying degrees of glucose tolerance. Acute insulin response to glucose (AIRg) correlated significantly with serum CBG concentrations at time 0 (r = -.38, P =.029), 22 minutes (r = -.41, P =.01), 50 minutes (r = -.41, P =.01), and 180 minutes (r = -.39, P =.02). Insulin sensitivity (S(I)) was not associated with serum CBG concentration at time 0 (r = -.16, P = not significant [NS]), but correlated significantly with CBG concentration at 22 minutes (r = -.41, P =.02) and 50 minutes (r = -.35, P =.048) of the FSIVGT. In lean subjects, serum CBG concentration decreased significantly after IV insulin from 37.9 +/- 5.4 to 35.4 +/- 3 mg/L (P =.02) and returned to basal levels thereafter. In contrast, obese, glucose-tolerant subjects had lower CBG levels than lean and obese glucose intolerant subjects (33.8 +/- 3.0 v 37.9 +/- 5.4 and 39.8 +/- 4.4 mg/L, respectively), and their serum CBG concentrations remained unchanged during FSIVGT. Mean serum-free insulin-like growth factor-I (IGF-I) concentrations steadily declined from 1.21 +/- 0.81 to 0.8 +/- 0.36 microg/L during the FSIVGT, and this effect was restricted to lean subjects. Basal serum-free IGF-I did not correlate with CBG levels at time 0, but correlated inversely with the serum CBG concentrations at 22 minutes (r = -.36, P =.04). Stepwise multivariant analysis showed that AIRg (P =.035) and S(I) (P =.046), but not free IGF-I levels, independently contributed to 28% of CBG variance at 22 minutes. These results suggest that insulin, but not IGF-I, constitutes an important negative regulator of CBG liver synthesis. Endogenous and exogenous insulin do not affect serum CBG concentrations in insulin-resistant obese subjects with preserved or decreased insulin secretion. Obese glucose-tolerant subjects are hypothesized to exhibit tonically inhibited serum CBG levels. In contrast, in lean subjects, the higher the insulin secretion the lower the serum CBG concentration. The mechanisms of this CBG inhibitory effect exerted by insulin and its implication on cortisol homeostasis and fat distribution in humans await further investigations.

No decrease in free IGF-I with increasing insulin in obesity-related insulin resistance

OBJECTIVE

Different facts suggest that the insulin growth factor (IGF)/ insulin growth factor-binding protein (IGFBP) system may be regulated by factors other than growth hormone. It has been proposed that, in healthy subjects, free IGF-I plays a role in glucose metabolism. The role of free IGF-I in glucose homeostasis in insulin resistance is poorly understood. This study was undertaken to evaluate the effects of acute changes in plasma glucose and insulin levels on free IGF-I and IGFBP-1 in obese and non-obese subjects.

RESEARCH METHODS AND PROCEDURES

Nineteen lean and 24 obese subjects were investigated. A frequently sampled intravenous glucose tolerance test was performed. Free IGF-I and IGFBP-1 were determined at 0, 19, 22, 50, 100, and 180 minutes.

RESULTS

Basal free IGF-I levels tended to be higher and IGFBP-1 lower in obese than in lean subjects. IGFBP-1 levels inversely correlated with basal insulin concentration. To determine the effects of insulin on the availability of free IGF-I and IGFBP-1, changes in their plasma concentrations were measured during a frequently sampled intravenous glucose tolerance test. After insulin administration, a significant suppression of free IGF-I at 22% was observed in lean subjects. In contrast, plasma-free IGF-I levels remained essentially unchanged in the obese group. The differences between both groups were statistically significant at 100 minutes (p < 0.01) and 180 minutes (p < 0.05). Serum IGFBP-1 was suppressed to a similar extent in both groups.

DISCUSSION

These data suggest that the concentrations of free IGF-I and IGFBP-1 are differentially regulated by obesity. Obesity-related insulin resistance leads to unsuppressed free IGF-I levels.

[Insulin secretion and insulin sensitivity in relation to glucose tolerance in a group of subjects at a high risk for type 2 diabetes mellitus]

BACKGROUND

Oral glucose tolerance test was evaluated, as well as, insulin sensitivity/secretion in a group of subjects at risk for type 2 diabetes mellitus.

METHOD

Metabolic profile of subjects included in the new category, impaired fasting glucose (IFG), was also evaluated.

RESULTS

IFG and impaired glucose tolerance identify different alterations in glucose homeostasis.

CONCLUSIONS

Those subjects with IFG are heterogeneous in their oral glucose tolerance. They display defects not only in insulin sensitivity but also in their capacity to compensate for it.

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.

[Analysis of mutations A3243G, C3256T and mitochondrial deletions in 41 diabetic patients]

BACKGROUND

Mutations or deletions of mitochondrial DNA (mtDNA) define a new diabetes subtype.

PATIENTS AND METHOD

The A3243G and C3256T mutations and mtDNA deletions were studied in 41 diabetic patients with maternally inherited diabetes mellitus or deafness.

RESULTS

The A3243G mutation was found in one out of forty-one diabetic patients (2.4%). Neither the C3256T mutation nor mtDNA deletions were detected.

CONCLUSIONS

The search of A3243G mutation has to be considered in a diabetic patient with deafness and/or maternal history of diabetes.

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.

[Prevalence of obesity in the population assisted at primary health care services in Girona, 1995-1999]

OBJECTIVES

To estimate the prevalence of obesity and overweight in the population of Girona (Spain) between 1995 and 1999 and to divide the prevalences in geographical areas according to age and sex.

METHODS

Height and weight were directly measures in 24,554 health care consumers older than 14 years (10,595 men and 13,959 women) treated in four primary health care areas: Girona 1, Girona 4, Salt and Camprodon and in one primary health care center in the province of Girona. Body mas index (BMI) was calcuted by dividing weight in kilograms bye height in meters squared. Obesity was defined as grades II and III of Garrow's index (BMI >= 30 kg/m2) and overweight as degree I (25 kg/m2 >= BMI < 30 kg/m2). Because the sample was not randomized, the prevalences were adequately weighted. The comparison between prevalences in two different primary health care areas for each sex (in the same Garrow's index and age group) was carried out using a parametric test of differences in proportions (Student's t-test). A hierarchical logistic regression was used to compare prevalences in the same grade Garrow's index, controlling for age and sex.

RESULTS

The prevalence of obesity was estimated as 15.6% in men aged from 20-74 years (from 14.0% in Girona 1 to 22.4% in Camprodon) and 17.5% for women (15.6% in Girona 1, 22.7% in Camprodon). The weighted mean was 16.7%. The prevalence of overweight was 44% in men and 33% in women and the weighted mean was 37.8%. The prevalence of obesity was graduated with statistically significant differences between Girona 1, Salt, Girona 4, Camprodon and Sils.

CONCLUSIONS

The estimates of the prevalences of obesity and overweight obtained in this study were closer to those of other studies in similar populations than previously believed. Indeed, the prevalences may be similar to those of the European Union and, in some age groups, to those of the United States.