To determine the effects of maternal diabetes on fetal iron status using serum transferrin receptors (STfR) and their ratio to ferritin (TfR‐F index) in cord blood.
Iron, ferritin, erythropoietin, STfR and haemoglobin concentration were measured and TfR‐F index calculated in 97 maternal/cord blood pairs. Forty‐nine women had type 1 diabetes (diagnosed before pregnancy) and these were compared with forty‐eight non‐ diabetic controls. The women with type 1 diabetes were recruited consecutively from attendance at the joint antenatal endocrine clinic while the control group of women was recruited from consecutive attendance at the remaining antenatal clinics.
The infants of the diabetic women had significantly lower levels of ferritin (47 vs 169 μg/l; p<0.01) and higher STfR (17.4 vs 12.9 mg/l; p<0.01) and TfR‐F index (10.4 vs 5.8; p<0.01) than controls. They were also significantly more acidotic at birth (7.25 vs 7.30; p<0.01), were born at an earlier gestation (36.7 vs 39.7 weeks; p<0.01) and had higher z Scores for weight (0.53 vs 0.02; p = 0.016).
Maternal diabetes causes depletion of fetal iron stores and is associated with higher fetal iron demands as indicated by higher STfR level and TfR‐F index in cord blood.
Limited data are available on the metabolic syndrome (MetS) and its components in elderly people (aged 70 years and over) at population level in Northern Europe. A study was undertaken to investigate the prevalence of MetS and its components in an aging population by using different definitions.
Design, setting, and subjects
A cross-sectional study of 539 inhabitants from Northern Finland (mean age 71.9 years) was conducted to investigate the prevalence of MetS, by using the definitions of MetS by the National Cholesterol Education Panel (NCEP), the modified NCEP (NCEPm), and the International Diabetes Federation (IDF).
Main outcome measures
Prevalence of MetS by the NCEP, NCEP modified, and IDF criteria.
Overall, the prevalence of MetS was 24.7%, 35.2%, and 37.2% in men, by NCEP, modified NCEP, and IDF-definitions, respectively. In women the corresponding figures were 20.9%, 33.1%, and 47.8%. Hypertension was the most common component in both men (91.8%) and women (89.0%) by the IDF criteria. Glucose abnormalities were particularly prevalent in men (53.2% by NCEP and 78.4% by IDF criteria).
The most common component was hypertension in both genders. Lower waist-circumference cut-off points of the IDF criteria led to a higher prevalence of MetS particularly in women. Prevalence of MetS varied significantly when measured by different definitions. Nearly half of older women met the IDF definition of MetS, which was more than twofold when compared with NCEP. Clinical practitioners should be aware of the limitations when using set criteria of MetS, in contrast to identifying the individual cardiovascular risk factors and the accumulation of these.
Elderly population; definitions; IDF; metabolic syndrome; prevalence
Metabolic syndrome (MetS) is increasingly common. Obesity has been suggested to associate with neck pain but prevalence of neck pain in subjects with MetS has not been studied. Aim of this study was to analyse the association between MetS and neck pain.
The study population consisted of 1294 middle-aged subjects in Pieksämäki, Finland. A total of 399 males and 500 females participated (69%). The mean age of both males and females was 46 years. Clinical and biochemical measurements were taken. The participants filled out a standard questionnaire. Psychological distress was assessed with the 12-item General Health Questionnaire (GHQ-12). Neck pain was defined as neck pain perceived daily. MetS was defined using National Cholesterol Education Program (NCEP) criteria. Statistical comparisons between the groups were performed using a bootstrap-type t-test or Chi-Square test. Risk ratios of having neck pain were calculated using generalised linear models with age, smoking, alcohol use, exercise and GHQ-12 score as covariates.
The prevalence of MetS was 33% in males and 29% in females. Neck pain was present in 11% (N = 42) of males and 19% (N = 93) of females (P < 0.001). The prevalence of neck pain was 7.9% (95% CI, 4.9% to 12%) among male subjects without MetS and 16% (95% CI, 10% to 23%) among those with MetS. The respective proportions among females were 16% (95% CI, 12% to 20%) and 25% (95% CI, 18% to 33%). The multivariate analysis showed an increased risk of neck pain in males with MetS (RR 2.1, 95% CI, 1.2 to 3.7, P = 0.010) and in females with MetS (RR 1.5, 95% CI, 1.0 to 2.1, P = 0.040).
MetS was associated with neck pain. This association was stronger in males, but the prevalence of neck pain was higher in females. Prospective studies should explore the potential causal association between neck pain and MetS and the potential common background factors of neck pain and MetS.
Background: Soluble transferrin receptor (sTfr) is a new marker of iron status and erythropoietic activity. It has been included in multivariable blood testing models for the detection of performance enhancing erythropoietin misuse in sport.
Objective: To evaluate the effect of different types and volumes of physical activity on sTfr concentration, variables of iron status (ferritin, transferrin, iron, and protein), and haematological indices.
Methods: Thirty nine subjects were divided into three groups: 1, untrained (n = 12); 2, moderately trained (n = 14); 3, highly trained (n = 13, seven men, six women). Groups 1 and 2 carried out two exercise tests: an incremental running test until exhaustion (test A) and a 45 minute constant speed running test at 70% VO2MAX (test B). Group 3 performed three days (women) or four days (men) of prolonged aerobic cycling exercise. The above variables together with haemoglobin and packed cell volume were analysed in venous blood samples before and after exercise. Changes in blood and plasma volume were estimated.
Results: sTfr levels were slightly increased in trained and untrained subjects immediately after test A. Test B and aerobic exercise had no significant effect on sTfr. Ferritin levels were increased after the laboratory tests for trained and untrained subjects and after prolonged aerobic exercise in male cyclists. Transferrin was increased significantly in trained and untrained subjects after both laboratory tests, but remained unchanged after prolonged exercise. Plasma and blood volumes were decreased after the laboratory tests but increased after aerobic exercise. No differences in the variables were observed between trained and untrained subjects with respect to response to exercise.
Conclusion: The changes in sTfr and the variables of iron status can be mainly attributed to exercise induced changes in volume. Taking these limitations into account, sTfr can be recommended as a marker of iron deficiency in athletes.
This Finnish population-based study, mean age 46 years, evaluates the association of high-sensitivity C-reactive protein (hs-CRP), interleukin-1 receptor antagonist (IL-1Ra), and
adiponectin with the NCEP and IDF definitions of metabolic
syndrome (MetS). Adiponectin levels were higher, hs-CRP and IL-1Ra
levels lower in subjects without MetS compared to subjects with
MetS. If MetS was present according to both IDF and NCEP criteria,
BMI, waist, triglycerides, hs-CRP, and IL-1Ra were significantly
higher compared to subjects who had MetS according to either only
IDF or only NCEP criteria. The hs-CRP, IL-1Ra, and adiponectin linearly
correlated with the number of the components of MetS according to
both definitions. Decreased levels of adiponectin and increased
levels of hs-CRP and IL-1Ra are tightly associated with the
components of MetS. Individuals who had MetS according to both
criteria had the most adverse changes in cardiovascular risk
The recent discovery of hepcidin, the key iron regulatory hormone, has changed our view of iron metabolism, which in turn is long known to be linked with insulin resistant states, including type 2 diabetes mellitus and the Metabolic Syndrome (MetS). Serum ferritin levels are often elevated in MetS (Dysmetabolic hyperferritinemia - DHF), and are sometimes associated with a true mild-to-moderate hepatic iron overload (dysmetabolic iron overload syndrome - DIOS). However, the pathophysiological link between iron and MetS remains unclear. This study was aimed to investigate, for the first time, the relationship between MetS and hepcidin at population level. We measured serum hepcidin levels by Mass Spectrometry in 1,391 subjects from the Val Borbera population, and evaluated their relationship with classical MetS features. Hepcidin levels increased significantly and linearly with increasing number of MetS features, paralleling the trend of serum ferritin. In multivariate models adjusted for relevant variables including age, C-Reactive Protein, and the HFE C282Y mutation, ferritin was the only significant independent predictor of hepcidin in males, while in females MetS was also independently associated with hepcidin. Overall, these data indicate that the fundamental iron regulatory feedback is preserved in MetS, i.e. that hepcidin tends to progressively increase in response to the increase of iron stores. Due to recently discovered pleiotropic effects of hepcidin, this may worsen insulin resistance and contribute to the cardiovascular complications of MetS.
OBJECTIVE—To examine the relationship between plasma IGF-1 and interleukin-6 (IL-6) levels in Caucasian nondiabetic subjects and evaluate the association of IGF-1 and IL-6 with the cardiometabolic risk factors characterizing metabolic syndrome (MetS).
RESEARCH DESIGN AND METHODS—The study group consisted of 186 Caucasian nondiabetic subjects who underwent an oral glucose tolerance test and an euglycemic-hyperinsulinemic clamp. A logistic regression analysis, adjusted for age and sex, was used to determine the association between tertiles of IGF-1 and IL-6 and the MetS and its components.
RESULTS—After adjusting for age and sex, both IGF-1 and IL-6 were correlated with insulin resistance and individual components of MetS, but in opposite directions. In the logistic regression model adjusted for age and sex, higher IL-6 and lower IGF-1 levels confer increased risk of having MetS and its two underlying pathophysiological abnormalities, i.e., visceral obesity and insulin resistance.
CONCLUSIONS—The present results raise the possibility that lowered protection against inflammation, i.e., lower IGF-1 levels, may have a role in the development of MetS and its features, resulting in an imbalance between proinflammatory and anti-inflammatory proteins.
Though inconsistent, a number of studies have shown an association between vitamin D (25(OH)D) status, parathyroid hormone (PTH) and the metabolic syndrome (Met S). These have largely been carried out in Caucasians or black subjects living in high income countries. There no data on the relationship of 25(OH)D and PTH status with Met S in populations resident in Africa. The aims of this study were to evaluate if there was an association of 25(OH)D or PTH with Met S in non-Caucasian populations in South Africa, and whether these molecules explained ethnic differences in the prevalence of Met S and its individual components.
We measured anthropometry, serum 25(OH)D and PTH levels and the components of Met S, plus related metabolic variables, in 374 African and 350 Asian Indian healthy adults from the greater Johannesburg metropolitan area.
Met S was diagnosed in 29% of the African and 46% of the Asian Indian subjects (p<0.0001). Subjects with Met S had higher PTH than those without Met S, (p<0.0001), whilst 25(OH)D levels were not significantly different (p = 0.50). In multivariate analysis, 25(OH)D was not associated with any components of the Met S however PTH was shown to be positively associated with systolic (p = 0.018) and diastolic (p = 0.005) blood pressures and waist circumference (p<0.0001) and negatively associated with HOMA (p = 0.0008) levels. Logistic regression analysis showed that Asian Indian ethnicity (OR 2.24; 95% CIs 1.57, 3.18; p<0.0001) and raised PTH (OR 2.48; 95% CIs 1.01, 6.08; p = 0.04; adjusted for 25(OH)D) produced an increased risk of Met S but 25(OH)D did not (OR 1.25; 95% CI 0.67, 2.24; p = 0.48).
Plasma PTH but not 25(OH)D is an independent predictor of the Met S in African and Asian Indians in South Africa.
Metabolic syndrome (MetS) is composed of cardiovascular risk factors including insulin resistance, obesity, dyslipidemia, and hypertension. Most of the components of MetS have been linked to the development of neoplasm. The purpose of this study was to evaluate the relationship between individual components of MetS and colorectal adenoma.
The study subjects were recruited from a pool of 4872 individuals who underwent a health check-up examination during the period January 2006 to May 2008. Each participant fulfilled a structured questionnaire. MetS was defined based on the America Heart Association and National Heart Lung Blood Institute criteria. Subjects with history of colon cancer, colon polyps, colitis, or prior colonic surgery were excluded.
A total of 4122 subjects were included for final analysis (2367 men and 1755 women; mean age, 49.6 ± 11.7 years). Of them, MetS was diagnosed in 708 men (29.9%) and in 367 women (20.9%). Among the patients with MetS, 34.6% had adenoma, 31.7% had hyperplastic polyps and 23.3% were polyp-free (p < 0.0001, Chi-square test). The adjusted OR for colorectal adenoma was significantly higher in the subjects with MetS (OR, 1.31, CI: 1.09-1.57). A stronger association between MetS and colorectal adenoma was found in men (OR:1.44, CI:1.16-1.80) than in women (OR:1.04, CI:0.74-1.46). The adjusted OR for adenoma increased as the number of MetS components increased (p for trend = 0.0001 ). When the individual components of MetS were analyzed separately, only central obesity (OR:1.36, CI:1.14-1.63), low HDL cholesterol levels (OR:1.30, CI:1.10-1.54) and high triglyceride levels (OR:1.26, CI:1.04-1.53) were independently associated with colorectal adenoma.
Of the components of MetS analyzed in this study, central obesity and dyslipidemia are independent risk factors for colorectal adenoma. With regard to the prevention of colorectal neoplasm, life-style modification such as weight reduction is worthwhile.
Epigenetic mechanisms may be involved in the regulation of genes found to be differentially expressed in the visceral adipose tissue (VAT) of severely obese subjects with (MetS+) versus without (MetS-) metabolic syndrome (MetS). Long interspersed nuclear element 1 (LINE-1) elements DNA methylation levels (%meth) in blood, a marker of global DNA methylation, have recently been associated with fasting glucose, blood lipids, heart diseases and stroke.
To test whether LINE-1%meth levels in VAT are associated with MetS phenotypes and whether they can predict MetS risk in severely obese individuals.
DNA was extracted from VAT of 34 men (MetS-: n = 14, MetS+: n = 20) and 152 premenopausal women (MetS-: n = 84; MetS+: n = 68) undergoing biliopancreatic diversion for the treatment of obesity. LINE-1%meth levels were assessed by pyrosequencing of sodium bisulfite-treated DNA.
The mean LINE-1%meth in VAT was of 75.8% (SD = 3.0%). Multiple linear regression analyses revealed that LINE-1%meth was negatively associated with fasting glucose levels (β = -0.04; P = 0.03), diastolic blood pressure (β = -0.65; P = 0.03) and MetS status (β = -0.04; P = 0.004) after adjustments for the effects of age, sex, waist circumference (except for MetS status) and smoking. While dividing subjects into quartiles based on their LINE-1%meth (Q1 to Q4: lower %meth to higher %meth levels), greater risk were observed in the first (Q1: odds ratio (OR) = 4.37, P = 0.004) and the second (Q2: OR = 4.76, P = 0.002) quartiles compared to Q4 (1.00) when adjusting for age, sex and smoking.
These results suggest that lower global DNA methylation, assessed by LINE-1 repetitive elements methylation analysis, would be associated with a greater risk for MetS in the presence of obesity.
Blood pressure; Epigenetics; Fasting glucose; Global DNA methylation; LINE-1; Metabolic syndrome; Severe obesity; Visceral adipose tissue
The aim of this study was to investigate the independent associations among cardiorespiratory fitness, metabolic syndrome (MetS), and C-reactive protein (CRP) in children. The sample consisted of 112 children (11.4 ± 0.4 years). Data was obtained for children's anthropometry, cardiorespiratory fitness, MetS components, and CRP levels. MetS was defined using criteria analogous to the Adult Treatment Panel III definition. A MetS risk score was also computed. Prevalence of the MetS was 5.4%, without gender differences. Subjects with low fitness showed significantly higher MetS risk (P < 0.001) and CRP (P < 0.007), compared to the high-fitness pupils. However, differences in MetS risk, and CRP between fitness groups decreased when adjusted for waist circumference. These data indicate that the mechanisms linking cardiorespiratory fitness, MetS risk and inflammation in children are extensively affected by obesity. Intervention strategies aiming at reducing obesity and improving cardiorespiratory fitness in childhood might contribute to the prevention of the MetS in adulthood.
The common characteristics of metabolic syndrome (MetS) and Cushing's syndrome suggest that excess cortisol may be involved in the pathogenesis of MetS. Salivary cortisol measurements are simple and can be surrogates for plasma free cortisol, which is the most biologically active form. We evaluated the association between levels of midnight salivary cortisol and MetS in Korean adults.
A total of 46 subjects, aged 20 to 70 years, who visited the Health Care Center at Konkuk University Hospital from August 2008 to August 2009 were enrolled. We compared the levels of midnight salivary cortisol in subjects with MetS with those in subjects without MetS. We analyzed the associations between midnight salivary cortisol levels and components of MetS.
Midnight salivary cortisol levels were higher in the MetS group (70±42.4 ng/dL, n=12) than that in the group without MetS (48.1±36.8 ng/dL, n=34) (P=0.001). Positive correlations were observed between midnight salivary cortisol levels and waist circumference, fasting blood glucose, and homeostasis model assessment of insulin resistance. The risk for MetS was significantly higher in subjects with midnight salivary cortisol levels ≥100 ng/dL than in those with levels <50 ng/dL (odds ratio, 5.9; 95% confidence interval, 2.35 to 36.4).
The results showed a positive correlation between midnight salivary cortisol levels and MetS, suggesting that hypercortisolism may be related to MetS.
Corticosteroid; Insulin resistance; Metabolic syndrome
Iron deficiency (ID) and iron deficiency anemia (IDA) are common nutritional disorders in children. Hepcidin, a peptide hormone produced in the liver, is a central regulator of systemic iron metabolism. We evaluated whether serum hepcidin levels can diagnose ID in children.
Sera from 59 children (23 males and 36 females; 5 months to 17 years) were analyzed for hepcidin-25 by ELISA. Patients were classified according to hemoglobin level and iron parameters as: IDA, (N=17), ID (N=18), and control (N=24).
Serum hepcidin, ferritin, soluble transferrin receptor (sTfR), transferrin saturation, and hemoglobin levels differed significantly between groups (P<0.0001). Serum hepcidin and ferritin levels (mean±SD) were 2.01±2.30 and 7.00±7.86, 7.72±8.03 and 29.35±24.01, 16.71±14.74 and 46.40±43.57 ng/mL in the IDA, ID, and control groups, respectively. The area under the receiver operating characteristic curve for serum hepcidin as a predictor of ID was 0.852 (95% CI, 0.755-0.950). Hepcidin ≤6.895 ng/mL had a sensitivity of 79.2% and specificity of 82.8% for the diagnosis of ID. Serum hepcidin levels were significantly correlated with ferritin, transferrin saturation, and hemoglobin levels and significantly negatively correlated with sTfR level and total iron binding capacity (P<0.0001).
Serum hepcidin levels are significantly associated with iron status and can be a useful indicator of ID. Further studies are necessary to validate these findings and determine a reliable cutoff value in children.
Serum hepcidin; Iron deficiency; Children
The existence of an association between lung function and metabolic syndrome (MetS) has been debated in cases involving non-obese subjects. To address this debate, we performed a cross-sectional study to investigate the association between lung function and MetS in both obese and non-obese populations.
The present study consisted of a total of 1,951 Korean male subjects. In this study group, we investigated relationships between lung function and MetS risk factors such as fasting serum glucose, systolic blood pressure (SBP), insulin resistance index, waist circumference (WC), and hemoglobin A1C level.
Forced vital capacity (FVC) values were significantly lower in the MetS group compared with those of the non-MetS group. In both non-obese (body mass index [BMI] < 25 kg/m2) and obese subjects (BMI ≥ 25 kg/m2), fasting serum glucose, hemoglobin A1C level, insulin resistance index, SBP, WC, and the prevalences of diabetes and MetS were significantly higher in subjects in the lowest FVC quartile compared with those in the highest FVC quartile. Odds ratios for the presence of MetS risk factors, after adjusting for age and height, ranged from 1.21 to 1.39 (P < 0.01) for a one standard deviation decrease in FVC.
The results of our study suggest that decreased vital capacity in Korean adult male subjects is associated with MetS, irrespective of obesity.
FEV1; FVC; Insulin resistance; Metabolic syndrome
Previous evidence supports the important role that oxidative stress (OxS) plays in metabolic syndrome (MetS)-related manifestations. We determined the relationship between the number of MetS components and the degree of OxS in MetS patients. In this comparative cross-sectional study from the LIPGENE cohort, a total of 91 MetS patients (43 men and 48 women; aged between 45 and 68 years) were divided into four groups based on the number of MetS components: subjects with 2, 3, 4 and 5 MetS components (n=20, 31, 28 and 12, respectively). We measured ischemic reactive hyperemia (IRH), plasma levels of soluble vascular cell adhesion molecule-1 (sVCAM-1), total nitrite, lipid peroxidation products (LPO), hydrogen peroxide (H2O2), superoxide dismutase (SOD) and glutathione peroxidase (GPx) plasma activities. sVCAM-1, H2O2 and LPO levels were lower in subjects with 2 or 3 MetS components than subjects with 4 or 5 MetS components. IRH and total nitrite levels were higher in subjects with 2 or 3 MetS components than subjects with 4 or 5 MetS components. SOD and GPx activities were lower in subjects with 2 MetS components than subjects with 4 or 5 MetS components. Waist circumference, weight, age, homeostatic model assessment-β, triglycerides (TGs), high-density lipoprotein and sVCAM-1 levels were significantly correlated with SOD activity. MetS subjects with more MetS components may have a higher OxS level. Furthermore, association between SOD activity and MetS components may indicate that this variable could be the most relevant OxS biomarker in patients suffering from MetS and could be used as a predictive tool to determine the degree of the underlying OxS in MetS.
cardiovascular risk factors; endothelial dysfunction; LIPGENE study; metabolic syndrome; oxidative stress; redox state
To examine the association between white blood cell (WBC) count and metabolic syndrome (MetS) by growth periods in black versus white individuals in the general population.
RESEARCH DESIGN AND METHODS
The study cohort consisted of 4,184 black and white preadolescents, adolescents, and adults. In this cohort, 743 adults were followed for 8.1–20.8 years longitudinally.
White versus black subjects had a significantly higher WBC count in all age-groups. WBC count was associated with more MetS components in whites than in blacks. Mean values of WBC increased significantly with increasing number of MetS components with adverse levels in adolescents and adults, with a stronger trend in whites. WBC count was longitudinally associated with MetS in whites only (P < 0.001).
The findings on the association between higher WBC count and MetS beginning in childhood, particularly in whites, underscore a potentially mechanistic link between systemic inflammation, MetS, and cardiovascular risk.
Growing evidence suggests that hypoadiponectinemia may play a significant role in the development of metabolic syndrome (MetS). Therefore, the relationships between serum adiponectin with MetS and components of MetS were investigated in non-diabetic samples of drawn from the Koreans general population.
Materials and Methods
We performed a cross-sectional study in samples of older Koreans (age > 40 years) including 2,471 men and 3,463 women. MetS was defined according to the Asian modified criteria of the National Cholesterol Education Program Adult Treatment Panel III report. Serum adiponectin concentrations were measured by radioimmunoassay.
The median adiponectin level in MetS was significantly lower than that in non-MetS subjects in men (6.00 vs. 8.00 µg/mL, p < 0.001) and women (10.12 vs. 11.74 µg/mL, p < 0.001). Adiponectin concentration was negatively correlated with waist circumference and levels of triglyceride, C-reactive protein (CRP), fasting glucose, and insulin, and positively correlated with high-density lipoprotein and age in both genders (p < 0.001). In a multivariate regression model after adjustment for age, body mass index, smoking, CRP, and lipid profiles, the odds ratio of MetS comparing extreme quartiles of adiponectin distribution was 0.32 [95% confidence interval (CI), 0.20 to 0.50] in men and 0.57 (95% CI, 0.43 to 0.76) in women.
Adiponectin levels are independently associated with the phenotype of MetS, as well as components of MetS in the non-diabetic Korean general population.
Adiponectin; metabolic syndrome; Korea
The genetic determinants of variation in iron status are actively sought, but remain incompletely understood. Meta-analysis of two genome-wide association (GWA) studies and replication in three independent cohorts was performed to identify genetic loci associated in the general population with serum levels of iron and markers of iron status, including transferrin, ferritin, soluble transferrin receptor (sTfR) and sTfR–ferritin index. We identified and replicated a novel association of a common variant in the type-2 transferrin receptor (TFR2) gene with iron levels, with effect sizes highly consistent across samples. In addition, we identified and replicated an association between the HFE locus and ferritin and confirmed previously reported associations with the TF, TMPRSS6 and HFE genes. The five replicated variants were tested for association with expression levels of the corresponding genes in a publicly available data set of human liver samples, and nominally statistically significant expression differences by genotype were observed for all genes, although only rs3811647 in the TF gene survived the Bonferroni correction for multiple testing. In addition, we measured for the first time the effects of the common variant in TMPRSS6, rs4820268, on hepcidin mRNA in peripheral blood (n = 83 individuals) and on hepcidin levels in urine (n = 529) and observed an association in the same direction, though only borderline significant. These functional findings require confirmation in further studies with larger sample sizes, but they suggest that common variants in TMPRSS6 could modify the hepcidin-iron feedback loop in clinically unaffected individuals, thus making them more susceptible to imbalances of iron homeostasis.
The aim of this study was to evaluate sensitivity and specificity for reticulocyte hemoglobin content (CHr) compared to other hematimetric and biochemical iron parameters, in particular, mean corpuscular hemoglobin (MCH), when screening for iron deficiency in elderly anemic patients. Bone marrow staining negative for iron was used as the gold standard criterion for iron deficiency anemia (IDA). Sensitivity and specificity for CHr, soluble transferrin receptor (sTfR), soluble transferrin receptor/log ferritin (TfR-F index), ferritin, MCH, and transferrin saturation were determined. The best cut-off point for CHr was 30.5 pg corresponding to a sensitivity and specificity of 93% and 69% for IDA, respectively. For MCH, a sensitivity of 93% and a specificity of 86%, respectively, correspond to an optimal cut-off of 28.5 pg. Analysis of CHr was not superior to MCH with respect to sensitivity and specificity when screening for IDA in elderly anemic patients.
Onset of the combined metabolic syndrome (MetS) is a complex progressive process involving numerous cardiovascular risk factors. Although patients with established MetS exhibit reduced coronary flow reserve and individual components of the MetS reduce microvascular vasodilation, little is known concerning the impact of early-stage MetS on the mechanisms of coronary flow control. Therefore, we tested the hypothesis that coronary arteriolar dilation to adenosine is attenuated in early-stage MetS by reduced A2 receptor function and diminished K+ channel involvement. Pigs were fed control or high-fat/cholesterol diet for 9 weeks to induce early-stage MetS. Coronary atheroma was determined in vivo with intravascular ultrasound. In vivo coronary dilation was determined by intracoronary adenosine infusion. Further, apical coronary arterioles were isolated, cannulated and pressurized to 60 cmH2O for in vitro pharmacologic assessment of adenosine dilation. Coronary atheroma was not different between groups, indicating early-stage MetS. Coronary arteriolar dilation to adenosine (in vivo) and 2-chloroadenosine (2-CAD; in vitro) was similar between groups. In control arterioles, 2-CAD-mediated dilation was reduced only by selective A2A receptor inhibition, whereas only dual A2A/2B inhibition reduced this response in MetS arterioles. Arteriolar A2B, but not A2A, receptor protein expression was reduced by MetS. Blockade of voltage-dependent K+ (Kv) channels reduced arteriolar sensitivity to 2-CAD in both groups, whereas ATP-sensitive K+ (KATP) channel inhibition reduced sensitivity only in control arterioles. Our data indicate that the mechanisms mediating coronary arteriolar dilation to adenosine are altered in early-stage MetS prior to overt decrements in coronary vasodilator reserve.
Ossabaw miniature swine; diabetes; coronary blood flow; potassium channel; obesity; adenosine receptor
In the present study, we tested whether the presence of metabolic syndrome (MetS) would worsen the features of inflammation, plasma omega 3 fatty acid levels and antioxidant potential in treated hypertensive patients.
Materials and Methods
Two groups were classified by the components of MetS: a reference group of treated hypertensive subjects: hypertension (HTN) group (n = 39) and with more than two additional MetS components: HTN with Mets group (n = 40). We further compared the parameters between HTN group and HTN with MetS group.
The results showed that age (p < 0.001) and body mass index (BMI) (p < 0.001) were significantly different between HTN group and HTN with MetS group. Age- and BMI-adjusted total radical trapping antioxidant potential (TRAP) (p < 0.01) was significantly lower, whereas age- and BMI-adjusted CD (p < 0.05) and interleukin (IL) 6 (p < 0.05) were significantly higher in HTN with MetS group than in HTN group. Moreover, HTN with MetS group had significantly lower levels of age- and BMI-adjusted plasma phospholipid eicosapentaenoic acid (EPA) than HTN group (p < 0.05). On the other hand, the levels of age- and BMI-adjusted intracellular cell adhesion molecule-1 (ICAM-1), adiponectin and high molecular weight (HMW)-adiponectin were not significantly different between the groups.
In conclusion, our results showed increased inflammatory marker, reduced antioxidant potential and EPA levels in treated hypertensive patients in the presence of MetS, suggesting the importance of changes of therapeutic lifestyle to modify the features of MetS.
Metabolic syndrome X; hypertension; oxidative stress; eicosapentaenoic acid; antioxidants; cytokines
The metabolic syndrome (MetS) is the clustering of cardiovascular risk factors and known as a powerful predictor of diabetes and cardiovascular disease. Glycated hemoglobin (HbA1c) is used as one of the diagnostic criteria for diabetes and category of increased risk for diabetes. We examined the usefulness of HbA1c as a diagnostic tool for MetS and to determine the cut-off value of HbA1c as a criterion for MetS, in non-diabetic Korean subjects. We analyzed 7,307 participants (male: 4,181, 57%) in a medical check-up program, and applied the newly recommended guidelines of the International Diabetes Federation for diagnosis of MetS. The mean HbA1c was 5.54% in all subjects and showed no significant difference between genders. Using receiver-operating characteristic curve, HbA1c value corresponding to the fasting plasma glucose value of 100 mg/dL was 5.65% (sensitivity 52.3%, specificity 76.7%). The prevalence of MetS was 8.5% according to the IDF guideline and 10.9% according to HbA1c value of 5.7%, showing 69.5% agreement rate. The detection rate of MetS increased to 25.7% using the HbA1c criterion of 5.7% instead of fasting hyperglycemia. This study suggests that HbA1c might be used as a diagnostic criterion for MetS and the appropriate cut-off value of HbA1c may be 5.65% in this Korean population.
Metabolic Syndrome; Fasting Hyperglycemia; HbA1c
Blood donors are at risk of iron deficiency. We evaluated the effects of blood donation intensity on iron and hemoglobin in a prospective study.
Four cohorts of frequent and first time or reactivated blood donors (no donation in 2 years), female and male, totaling 2425 were characterized and followed as they donated blood frequently. At enrollment and the final visit, ferritin, soluble transferrin receptor (sTfR), and hemoglobin were determined. Models to predict iron deficiency and hemoglobin deferral were developed. Iron depletion was defined at two levels: Iron Deficient Erythropoiesis (IDE) [log (soluble transferrin receptor/ferritin ≥ 2.07)] and Absent Iron Stores (AIS) (ferritin < 12 ng/mL).
Among returning female first time/reactivated donors, 20% and 51% had AIS and IDE at their final visit, respectively; corresponding proportions for males were 8% and 20%. Among female frequent donors who returned, 27% and 62% had AIS and IDE, respectively, while corresponding proportions for males were 18% and 47%. Predictors of IDE and/or AIS included a higher frequency of blood donation in the last 2 years, a shorter interdonation interval, and being female and young; conversely, taking iron supplements reduced the risk of iron depletion. Predictors of hemoglobin deferral included female gender, Black race and a shorter interdonation interval.
There is a high prevalence of iron depletion in frequent blood donors. Increasing the interdonation interval would reduce the prevalence of iron depletion and hemoglobin deferral. Alternatively, replacement with iron supplements may allow frequent donation without the adverse outcome of iron depletion.
Donors; Hematology – Red Cells; Blood Center Operations
Whether the metabolic syndrome (MetS) has prognostic value for coronary artery disease (CAD) beyond its individual components is controversial. We compared the relationship between the number of MetS components and CAD severity as assessed by angiography in non-diabetic and diabetic subjects. We consecutively enrolled 527 patients who underwent their first coronary angiography. Patients were divided into four groups according to the number of MetS components: 0/1, 2, 3, and 4/5. A coronary atherosclerosis score was used to quantify the extent of atherosclerotic involvement. The relationship between the MetS score and angiographic CAD severity or clinical presentation was compared between non-diabetic and diabetic subjects. Individuals with the MetS (n = 327) had a higher prevalence of CAD (60% vs 32%, P < 0.001), multi-vessel disease (34% vs 16%, P < 0.001), and acute coronary syndromes (49% vs 26%, P < 0.001) than those without the MetS. In the non-diabetic group, atherosclerosis score increased with the MetS score (1.0 ± 2.1, 2.0 ± 2.9, 2.8 ± 2.9, and 3.6 ± 3.9, P < 0.001) whereas there was no significant difference in the diabetic group (0.5 ± 1.0, 5.2 ± 4.7, 4.2 ± 2.9, and 4.4 ± 3.5, P = 0.102). The MetS score is related to CAD severity in non-diabetic patients but the association between the MetS score and angiographic CAD severity may be obscured in the presence of diabetes.
Metabolic Syndrome; Coronary Atherosclerosis; Coronary Angiography
Although the association of weight gain and developing metabolic syndrome (MetS) has been reported in the Western and Asian populations, data on the gender-stratified effects of weight change (including weight loss) on incident MetS and its components in the Middle East Caucasians is still scarce.
A total of 1431 men and 2036 women aged ≥ 20 years with BMI > 18.5 kg/m2 were followed over 3 years. Multivariate logistic regression analysis was used to estimate the relative risk (RR) of MetS and its components (the Adult Treatment Panel III definition) associated with gender-stratified quintiles of percent weight change. Subjects with MetS at baseline were excluded for analyzing the RR of MetS.
There was 20.4% (95% CI, 19.6–21.2) age-adjusted incident MetS (18.4% male vs. 23.1% women). In men, mild weight gain (WG) predicted high waist circumference (WC) and high triglyceride; moderate WG predicted MetS (RR 2.5, 95% CI 1.4–4.3), high WC and high blood pressure (BP); large WG predicted MetS (RR 3.2, 95% CI 1.8–5.7) and its components, except for high fasting plasma glucose. In women, mild WG predicted MetS (RR 2.5, 95% CI 1.4–4.3), high WC and high BP; moderate WG predicted Mets (RR 4.6, 95% CI 2.7–8.0), high WC and high triglyceride; large WG predicted MetS (RR 6.6, 95% CI 3.8–11.3) and its components except for low HDL-cholesterol. Mild weight loss had protective effect on high WC in both genders and MetS in men (RR 0.5, 95% CI 0.26–0.97, P = 0.04).
Weight change showed different effects on MetS in men and women. In women, mild WG predicted MetS; however, mild weight loss was protective against MetS in men and high WC in both genders.