Quantitative Insulin Sensitivity Check Index Index Research Articles

Effects of ginseng berry saponins from panax ginseng on glucose metabolism of patients with prediabetes: A randomized, double-blinded, placebo-controlled, crossover trial

BackgroundPrediabetes strongly increases the risk of type 2 diabetes and cardiovascular events. However, lifestyle intervention, the first-line treatment for prediabetes currently, was inconsistently beneficial for glucose metabolism, and the conventional medicines, such as metformin, is controversial for prediabetes due to the possible side effects. PurposeThis study was designed to evaluate the effects of Zhenyuan Capsule, a Chinese patented medicine consisting of ginseng berry saponins extracted from the mature berry of Panax Ginseng, on the glucose metabolism of prediabetic patients as a complementary therapy. Study design and methodsIn this randomized, double-Blinded, placebo-controlled, crossover trial, 195 participants with prediabetes were randomized 1:1 to receive either placebo followed by Zhenyuan Capsule, or vice versa, alongside lifestyle interventions. Each treatment period lasted 4 weeks with a 4-week washout period in between. The primary outcomes were the changes in fasting plasma glucose (FPG) and 2-h postprandial plasma glucose (2-h PG) from baseline. Secondary outcomes includes the changes in fasting and 2-h postprandial insulin and C-peptide, the homeostatic model assessment-insulin resistance (HOMA-IR) index and quantitative insulin sensitivity check index (QUICKI) from baseline. Blood lipids and adverse events were also assessed. ResultsCompared with placebo, Zhenyuan Capsule caused remarkable reduction in 2-h PG (-0.98 mmol/l) after adjusting treatment order. Zhenyuan Capsule also reduced the fasting and 2-h postprandial levels of insulin and C-peptide, lowered HOMA-IR index (-1.26), and raised QUICKI index (+0.012) when compared to placebo. Additionally, a significant increase in high density lipoprotein cholesterol (HDL-C; +0.25 mmol/l) was found in patients with Zhenyuan Capsule. No serious adverse event occurred during the study. ConclusionsAmong prediabetic patients, Zhenyuan Capsule further reduced 2-h PG level, alleviated insulin resistance and raised HDL-C level on the background of lifestyle interventions. The study protocol is registered with the Chinese Clinical Trial Registry (ChiCTR2000034000).

The Value of Insulin Resistance indices For detecting Insulin Resistance in Polycystic Ovarian Syndrome Patients

Polycystic Ovarian Syndrome (PCOS) is characterized by increased ovarian and androgen hormone secretion. Patients with PCOS are said to be at high risk for insulin resistance(IR). IR is a sign of PCOS that comprises impaired glucose tolerance and elevated insulin production. HOMA-IR is a test that assesses insulin resistance by measuring blood glucose and insulin levels. There are other indexes that are also available for determining IR such as the quantitative insulin sensitivity check index(QUICKI) and McAuley index. Hence, in this study HOMA-IR, QUICKI and McAuley index were used to determine the IR among PCOS individuals. This case-control cross sectional study included 62 participants between the age group of 20-40 years. They were divided into two groups such as Group B which includes 31 PCOS patients diagnosed based on Rotterdam criteria and Group A includes 31 healthy age-matched female participants. After obtaining informed consent, fasting blood sample was collected from all the participants. Based on the analyzed biochemical parameters IR was assessed using HOMA-IR, QUICKI and McAuley index. For statistical analysis student t-test, ROC curve and bivariate regression analysis were done. In this study, it is observed that an increase in BMI was at a higher risk of developing PCOS. It is seen that fasting glucose, insulin and lipid profile (except HDL-C) were significantly elevated in PCOS individuals. The HOMA-IR was significantly increased and QUICKI and McAuley’s index were significantly decreased in PCOS which shows that PCOS patients are at higher risk of developing IR. Crude odds were calculated which shows that increase in HOMA-IR levels has an 86.25% increase risk of developing IR in PCOS patients when compared with the other indexes.HOMA-IR has a higher predictor % of developing IR in PCOS individuals, but still QUICKI and McAuley index can also be used as a predictor of risk.

The effects of citrulline supplementation on meta-inflammation and insulin sensitivity in type 2 diabetes: a randomized, double-blind, placebo-controlled trial

BackgroundThis study aimed to examine the effects of l-citrulline (l-CIT) on low-grade inflammation (meta-inflammation) and insulin sensitivity in type 2 diabetes (T2D) patients since it has exhibited hypoglycemic and anti-inflammatory effects in most animal studies.MethodsIn this double-blind, placebo-controlled randomized clinical trial, 54 patients with T2D referred to specialized clinics of Tabriz University of Medical Sciences were assigned to l-CIT group (receiving orally one 3 g sachet of l-CIT daily before breakfast) or placebo group (receiving orally one 3 g sachet of microcrystalline cellulose daily before breakfast) for eight weeks. Serum levels of fasting blood glucose, hemoglobin A1c (HbA1c), CIT, monocyte chemoattractant protein 1 (MCP-1), interleukin-6 (IL-6), and toll-like receptor 4 (TLR-4) were determined. The quantitative insulin sensitivity check index (QUICKI) and homeostatic model assessment of β-cell function (HOMA-B) index were estimated at the baseline and post-intervention.ResultsNo significant difference was observed between the studied parameters at the baseline. l-CIT supplementation significantly reduced not only serum concentrations of fasting blood glucose but also HbA1c, serum IL-6 and TLR-4 levels in the l-CIT group (p < 0.05). Additionally, at the end of the study serum levels of CIT increased significantly in l-CIT group compared to the baseline and placebo group. Fasting blood glucose concentrations and HbA1c significantly decreased after the intervention compared to the placebo. There was no significant difference in serum IL-6, TLR-4, MCP-1 levels, as well as QUICKI and HOMA-B index between the two groups, even after adjusting for baseline variables and confounders.ConclusionsOur findings revealed that, although l-CIT supplementation significantly reduced fasting blood glucose concentrations, HbA1c and increased serum levels of CIT. It seems it could not significantly improve insulin sensitivity and meta-inflammation biomarkers. Additional studies with longer duration and different doses of l-CIT are required.Trial registration The protocol of this clinical trial is registered at the Iranian Registry of Clinical Trials (registration no: IRCT20100209003320N16 at www.irct.ir)

Insulin resistance and bone health in adolescents.

Previous studies are suggestive of the protective role of insulin on bone in adults. Whether this association exists in younger individuals is not clear, yet. This investigation aimed to evaluate the association between insulin resistance, bone parameters, and body composition amongst Iranian adolescents᾽ population. A cross-sectional study was conducted on 423 participants (224 girls and 199 boys) aged 9-19 years old. Insulin resistance was assessed, using a homeostatic model assessment of insulin resistance (HOMA-IR) and quantitative insulin sensitivity check index (QUICKI). Bone mineral density (BMD), bone mineral content (BMC), total body fat mass (TBFM), and total body lean mass (TBLM) were measured, using dual energy X-ray absorptiometry (DXA), and bone mineral apparent density (BMAD) was calculated. In multiple regression analyses adjusted for potential confounders, the HOMA-IR showed statistically significant negative association with most of the bone parameters (β = - 1.1 to - 0.002, P = 0.004 to 0.036). On the subject of QUICKI index, this relationship was detected only for lumbar spine (LS) parameters (β = 0.062 to 37.21, P = 0.0001 to 0.026) and femoral neck bone mineral content (FNBMC) (β = 1.297, P = 0.013). Our results suggest that insulin resistance may be inversely and independently associated with the bone indices in younger individuals. Whether high insulin levels have detrimental effects on growing bone is still unclear and has to be answered.

Insulin Sensitivity Indices in Patients with Polycystic Ovary Syndrome with Different Body Mass Index Categories.

This study aimed to determine the prevalence of insulin resistance among women with polycystic ovary syndrome (PCOS), describe the clinical and biochemical characteristics of women with PCOS, and determine the association between Antimullerian Hormone (AMH) and PCOS. In a clinical case series, 544 women with PCOS were included in this study. Body mass index (BMI), Homeostasis Model Assessment (HOMA), Quantitative Insulin Sensitivity Check Index (QUICKI), and Matsuda index were calculated. Sixty-three women with PCOS and 50 age- and BMI-matched control patients underwent blood sampling for AMH level. The most common clinical presentation of PCOS in this study was menstrual irregularity followed by hirsutism and infertility. There was no statistically significant difference in the clinical presentation or hormonal profile in women with PCOS according to different BMI categories. The prevalence of insulin resistance among women with PCOS was 37.7%, 69.3%, and 75.8% using HOMA, QUICKI, and Matsuda index, respectively. Furthermore, the Matsuda index had the highest detection rate of insulin resistance, especially in underweight women with PCOS (94.1%). AMH levels in women with PCOS were significantly higher than that in the control group (P-value = 0.015). Insulin resistance is prevalent among women with PCOS. The detection rate of insulin resistance varies according to the insulin sensitivity index used. Menstrual irregularity was the most common presentation of PCOS. Women with PCOS have significantly higher levels of AMH levels compared to women in the control group.

Effects of resveratrol nanocapsules on the quantitative insulin sensitivity check index in insulin resistance: a study on metabolic syndrome induce mice

The aim of this study is to evaluate the effect of resveratrol nanocapsules (RV-NCs) by quantitative insulin sensitivity check index (QUICKI) for insulin resistance diagnosis on metabolic syndrome induction in mice. Next, the applicability of these nanocapsules (NCs) was evaluated in metabolic syndrome induced in 40 mice. RV-NCs were synthesized by interfacial deposition method and was analyzed by various methods including Zetasizer, high-performance liquid chromatograph, potentiometer and scanning electron microscopy. The analysis results show a zeta potential of − 7.15, loading efficiency of 99.54 ± 1.02% and particle size of 207 nm for RV-NC production. Collected data from mice examination were analyzed by ANOVA and Tukey criteria. The validity and the reproducibility of the QUICKI index in a population of mice were determined and found that is a significant difference between high fat diet group and the control group (p < 0.05). In addition, the result obtained by the Tukey test indicated the difference in insuline and glucose levels of these group. Also, it probably is associated with the increase in the in vivo stability, which is obtained by the effective formulation of nanocapsules for resveratrol delivery.

The association of quantitative insulin sensitivity indices (HOMA-IR and QUICKI) with anthropometric and cardiometabolic indicators in adolescents.

IntroductionHomoeostasis model assessment (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI) are used to evaluate insulin resistance. The aim of this study was to investigate the association between quantitative insulin sensitivity indices and anthropometric and cardiometabolic indicators in adolescents.Material and methodsThis descriptive-analytic cross-sectional study was conducted on 80 adolescents aged 12 to 13 years in Isfahan, Iran. Anthropometric, cardiometabolic and QUICKI and HOMA-IR indicators were measured. In the results analysis, Pearson correlation coefficient and regression analysis were used.ResultsThere was a significant positive correlation between most of the anthropometric indicators and the HOMA-IR index and a significant negative correlation with QUICKI (all p < 0.0001). Moreover, serum triglyceride level had a significant negative correlation with QUICKI index (R = –0.33, p = 0.002) and systolic blood pressure (R = 0.44, p < 0.0001), and triglyceride level (R = 0.66, p < 0.0001) had a significant positive correlation with HOMA index. The results of these two indices were highly correlated in most of the anthropometric and biochemical indices, except for the waist circumference to the neck circumference ratio and systolic blood pressure, which had a significant positive association with HOMA-IR, but did not show a significant association with QUICKI index.ConclusionsA significant correlation between anthropometric and cardiometabolic indicators with insulin resistance indices (HOMA-IR and QUICKI) was found. Moreover, the results of these two indices were highly correlated in most of the anthropometric and biochemical indices, except for the waist circumference to the neck circumference ratio and systolic blood pressure.

Differential performance of surrogate indices of fasting insulin resistance in low-birthweight and normal-birth weight cohorts: Observations from Hyperinsulinaemic-Euglycaemic clamp studies in young, Asian Indian males

AimTo evaluate the predictive accuracy of surrogate measures of fasting insulin resistance/sensitivity like the Homeostasis model assessment for insulin resistance (HOMA –IR), Fasting glucose/insulin ratio (FG-IR), Quantitative insulin sensitivity check index (QUICKI), and the 20/fasting C peptide x fasting plasma glucose [20/(FCP × FPG)] index in comparison to M value derived from hyperinsulinaemic-euglycaemic clamp (HEC) studies in two birth weight based cohorts of Asian Indian males. MethodsHEC studies were performed in non-diabetic Asian Indian males (n = 117), born of normal birth weight (n = 59, birth weight > 2.5 kgs) and low birth weight (n = 58, birth weight < 2.5 kgs). Anthropometry and biochemical analysis were done. Surrogate indices of fasting insulin resistance were calculated and data were analysed by Pearson's correlation and Random calibration model analysis. ResultsAmongst surrogate indices of fasting insulin resistance/sensitivity, the mean values for HOMA-IR, QUICKI, FG-IR, 20/(FCP × FPG) index and M value were similar between the two groups. Significant positive correlation was observed for FG-IR and QUICKI with M value (the gold standard measure of insulin sensitivity derived from HEC procedure) in the low birth weight cohort in contrast to the normal birth weight cohort, wherein no significant correlation was observed for any of the indices. Random calibration model analysis showed highest predictive accuracy for QUICKI in both the study groups. ConclusionThe QUICKI index showed highest predictive accuracy in the normal birth weight and the low birth weight cohorts of Asian Indian males.

Vitamin D and Testosterone in Healthy Men: A Randomized Controlled Trial.

Available evidence shows an association of vitamin D with androgen levels in men. However, results from preliminary randomized controlled trials (RCTs) are conflicting. To evaluate whether vitamin D supplementation increases total testosterone (TT) levels in healthy men. The Graz Vitamin D&TT-RCT is a single-center, double-blind, randomized, placebo-controlled trial conducted between December 2012 and January 2017. Endocrine outpatient clinic at the Medical University of Graz, Austria. Ninety-eight healthy men with TT levels ≥10.4 nmol/L and 25-hydroxyvitamin D [25(OH)D] levels <75 nmol/L completed the study. Subjects were randomly assigned to receive 20,000 IU/wk of vitamin D3 (n = 50) or placebo (n = 50) for 12 weeks. Primary outcome was TT measured using mass spectrometry. Secondary outcomes were free testosterone, sex hormone-binding globulin, estradiol, follicle-stimulating hormone, and luteinizing hormone levels; free androgen index; metabolic characteristics; and body composition. In healthy men [mean values ± standard deviation: age, 39 years (±13 years); 25(OH)D level, 53.3 nmol/L (±18.3 nmol/L); TT, 19.1 nmol/L (±5.6 nmol/l)], no significant treatment effect on TT was found; however, there were significant effects on quantitative insulin sensitivity check index (QUICKI) and a trend toward decreased Matsuda index. In the treatment group, median (interquartile range) changes for TT, QUICKI, and Matsuda index were 0.5 nmol/L (-0.63 to 0.63 nmol/L; P = 0.497), -0.02 (-0.04 to 0.01; P = 0.034), and -0.9 (-3.2 to 0.8; P = 0.051), respectively. Vitamin D treatment had no effect on TT levels in middle-aged healthy men with normal baseline TT, but it significantly decreased QUICKI. Additional studies investigating vitamin D effects on TT and insulin sensitivity in healthy men are required.

The Association of Osteocalcin and Adiponectin with Glucose Metabolism in Nondiabetic Postmenopausal Women

Background/Aim: This study was designed to determine if osteocalcin is associated with insulin resistance, metabolic risk factors and adiponectin levels in nondiabetic postmenopausal women. Methods: A total of 87 menopausal nondiabetic subjects were enrolled into the study. Levels of fasting plasma glucose (FPG), insulin and serum lipids were determined. To estimate insulin sensitivity, homeostasis model assessment (HOMA-IR) and the quantitative insulin sensitivity check index (QUICKI) were used. Serum total osteocalcin and adiponectin levels were measured and the features of metabolic syndrome were identified. Results: The mean age of the patients was 54.7 years. Among the participants, 28.7% were obese (body mass index, BMI, ≥30). Insulin resistance was detected by HOMA-IR in 42.5% and by the QUICKI index in 63.2% of the cases. Metabolic syndrome was present in 29.8% of the patients. Neither the baseline characteristics nor the metabolic risk factors were correlated with osteocalcin or adiponectin levels (p > 0.05). When the patients were analyzed regarding BMI, osteocalcin levels were significantly lower in overweight women. Serum adiponectin levels were significantly lower in women with metabolic syndrome. Conclusion: No correlation between total osteocalcin and FPG, fasting insulin and insulin resistance parameters was found in nondiabetic postmenopausal women. Serum levels of adiponectin were associated with metabolic syndrome.

The effect of ginger powder supplementation on insulin resistance and glycemic indices in patients with type 2 diabetes: A randomized, double-blind, placebo-controlled trial

To identify the effect of some herbal products on insulin resistance. Regarding the scientific evidences existing about ginger, this research was therefore carried out to identify the effect of ginger supplementation on insulin resistance and glycemic indices in diabetes mellitus. This is a randomized, double-blind, placebo-controlled trial in which 88 participants affected by diabetes were randomly assigned into ginger (GG) and placebo (PG) groups. The GG received 3 one-gram capsules containing ginger powder whereas the PG received 3 one-gram microcrystalline-containing capsules daily for 8 weeks. HbA1c, fructosamine, fasting blood sugar (FBS), fasting insulin, homeostasis model assessment insulin resistance index (HOMA-IR), β-cell function (β%), insulin sensitivity (S%) and the quantitative insulin sensitivity check index (QUICKI) were assessed before and after the intervention. FBS mean showed a decrease of 10.5% (p=0.003) in the GG whereas the mean had an increase of 21% in the PG (p=0.01). Variation in HbA1c mean was in line with that of FBS. Statistical difference was found in the two groups before and after the intervention in terms of median of fasting insulin level, S% and HOMA-IR (P<0.005). Moreover QUICKI mean increased significantly in the two groups, the mean difference, however, was significantly higher in the GG. The study demonstrated that daily consumption of 3 one-gram capsules of ginger powder for 8 weeks is useful for patients with type 2 diabetes due to FBS and HbA1c reduction and improvement of insulin resistance indices such as QUICKI index.

Moderate diet-induced weight loss is associated with improved insulin sensitivity in middle-aged healthy obese Korean women.

BACKGROUND/OBJECTIVEThe goal of the present study was to investigate the effects of moderate caloric restriction on β-cell function and insulin sensitivity in middle-aged obese Korean women.SUBJECTS/METHODSFifty-seven obese pre-menopausal Korean women participated in a 12-week calorie restriction program. Data on total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), triglycerides (TG), and fasting serum levels of glucose, insulin, C-peptide, blood pressure, leptin and anthropometrics were collected. A dietary intake assessment was based on three days of food recording. Additionally, β-cell function [homeostasis model assessment of β-cell (HOMA-β), insulinogenic index (ISI), C-peptide:glucose ratio, and area under curve insulin/glucose (AUCins/glu)] and insulin sensitivity [homeostasis model assessment for insulin resistance (HOMA-IR), Quantitative insulin-sensitivity check index (QUICKI) and Matsuda index (MI)] were recorded.RESULTSWhen calories were reduced by an average of 422 kcal/day for 12 weeks, BMI (-2.7%), body fat mass (-10.2%), and waist circumference (-5%) all decreased significantly (P < 0.05). After calorie restriction, weight, body fat percentage, hip circumference, BP, TC, HDL-C, LDL-C, plasma glucose at fasting, insulin at fasting and 120 min, AUCglu and the insulin area under the curve all decreased significantly (all P < 0.05), while insulin sensitivity (HOMA-IR, QUICKI and Matsuda index) measured by OGTT improved significantly (P < 0.01).CONCLUSIONSModerate weight loss due to caloric restriction with reduction in insulin resistance improves glucose tolerance and insulin sensitivity in middle-aged obese women and thereby may help prevent the development of type 2 diabetes mellitus.

Anti-Mullerian hormone and insulin resistance in classic phenotype lean PCOS

This study is designed to explore the correlation between AMH levels and IR in normal weight PCOS women. This prospective study was conducted on 55 patients, who were admitted to obstetrics and gynecology department of a university clinic. Study group was consisted of 34 patients diagnosed as polycystic ovary syndrome (PCOS) according to the Rotterdam Criteria, whereas control group was consisted of 21 healthy volunteers without any features of clinical or biochemical hyperandrogenism, who had regular menstrual cycles. BMI≥25kg/m(2) were considered overweight and obese and excluded. Blood samples were obtained during days 2-3 after spontaneous menses or progesterone-induced withdrawal bleeding after overnight fasting for at least 12h. The weight, height, hip and waist circumferences of the patients were measured. Fasting insulin and glucose (FPG) levels were used for calculating different insulin resistance indexes (Homeostatic Model Assessment (HOMA-IR), Quantitative Insulin Sensitivity Check Index (QUICKI)). No significant difference was found between PCOS and control groups regarding the mean age, BMI, waist to hip ratio (WHR), mean values of FPG, FPG/insulin ratio and HOMA B (p>0.05). AMH values were significantly higher in PCOS cases when compared with controls (4.7 vs. 3.4ng/mL) (p<0.05).The mean values of HOMA-IR and QUICKI indexes were significantly higher among PCOS cases when compared with controls. E2 levels were significantly lower and Total-T were significantly higher in PCOS patients. When PCOS cases are categorized according to the existence of IR, no difference in Total-T and AMH levels between both groups. Although not statistically significant, a negative correlation of AMH with HOMA-IR and a positive correlation with QUICKI index were found. Among the hormone parameters, AMH was found to be positively correlated with Total-T (r=0.332, p=0.013). Although the relation between AMH and androgen production is supported by current evidence, the mechanism underlying the relation between AMH and insulin resistance is not clear yet.

Effects of ginger (Zingiber officinale) on plasma glucose level, HbA1c and insulin sensitivity in type 2 diabetic patients

The present study was aimed to evaluate the effects of Zingiber officinale on some biochemical parameters in type 2 diabetic (DM2) patients. In a randomized double-blind placebo controlled trial, 64 patients with DM2 were assigned to ginger or placebo groups (receiving 2 g/d of each). A 3 d diet record, anthropometric measurements and concentrations of fasting blood glucose (FPG), HbA1c, lipid profile (including total cholesterol, triglyceride, low density lipoprotein and high density lipoprotein) and also the homeostasis model assessment (HOMA) and quantitative insulin-sensitivity check index (QUICKI) were determined before and after 2 months of intervention. Ginger supplementation significantly lowered the levels of insulin (11.0 ± 2.3 versus 12.1 ± 3.3; p = 0.001), LDL-C (67.8 ± 27.2 versus 89.2 ± 24.9; p = 0.04), TG (127.7 ± 43.7 versus 128.2 ± 37.7; p = 0.03) and the HOMA index (3.9 ± 1.09 versus 4.5 ± 1.8; p = 0.002) and increased the QUICKI index (0.313 ± 0.012 versus 0.308 ± 0.012; p = 0.005) in comparison to the control group; while, there were no significant changes in FPG, TC, HDL-C and HbA1c (p > 0.05). In summary, ginger supplementation improved insulin sensitivity and some fractions of lipid profile in DM2 patients. Therefore it may be considered as a useful remedy to reduce the secondary complications of DM2.

Relationship between free fatty acids, insulin resistance markers, and oxidized lipoproteins in myocardial infarction and acute left ventricular failure

BackgroundThe most common cause of myocardial infarction (MI) is stenotic atherosclerotic lesions in subepicardial coronary arteries. Artery disease progression induces clinical signs and symptoms, among which MI is the leader in mortality and morbidity. Recent studies have been trying to find new biochemical markers that could predict the evolution of clinical complications; among those markers, free fatty acids (FFA) and oxidative modification of low-density lipoproteins (oxidized LDL) have a special place.Materials and methodsSeventy-nine ST-elevation MI patients were enrolled. The first group included MI patients without the signs of acute heart failure (Killip class I) while MI patients with Killip classes II–IV made up the second group. Thirty-three individuals with no cardiovascular disease were the controls. The lipid profile, serum oxidized LDL, and their antibodies, C-peptide and insulin were measured at days 1 and 12. The level of insulin resistance was assessed with the quantitative insulin sensitivity check index (QUICKI).ResultsMI patients had atherogenic dyslipidemia; however, the Killip II–IV group had the most pronounced and prolonged increase in FFA, oxidized LDL, and their antibodies. Additionally, positive correlations between FFA levels and creatine kinase activity (12 days, R = 0.301; P = 0.001) and negative correlations between the QUICKI index and FFA levels (R = −0.46; P = 0.0013 and R = −0.5; P = 0.01) were observed in the both groups.ConclusionThe development of MI complications is accompanied by a significant increase in FFA levels, which not only demonstrate myocardial injury, but also take part in development of insulin resistance. Measuring FFA levels can have a great prognostic potential for risk stratification of both acute and recurrent coronary events and choice of treatment strategy.

The Association of Insulin Resistance with Subclinical Thyrotoxicosis

Although overt thyrotoxicosis is associated with reduced insulin sensitivity (IS), the effects of subclinical thyrotoxicosis (SCTox) (i.e., suppressed serum thyroid-stimulating hormone with free thyroxine and tri-iodothyronine within the reference range) on glucose metabolism are not clear. SCTox may be of endogenous origin or due to ingestion of supraphysiological amounts of thyroid hormone. Our hypotheses were that reduced IS is present in SCTox and that the degree of reduction differs between SCTox of endogenous and exogenous origin. The study population consisted of 125 premenopausal, normal-weight women, divided into four groups: exogenous SCTox due to L-T4 treatment for benign goiter or hypothyroidism (SCTox-ExogG) (n = 53), endogenous SCTox (SCTox-Endog) (n = 12), exogenous SCTox due to L-T4 treatment for differentiated thyroid cancer (SCTox-ExogDTC) (n = 20), and finally euthyroid women (C) (n = 40) as a control group. After a mixed meal challenge, glucose and insulin were determined at baseline and 120 minutes later. IS was assessed by homeostasis model assessment of insulin resistance (HOMA-IR) index, quantitative IS check index (QUICKI), and 2 hours IS Avignon's index amended by Aloulou for mixed food. Secretion by pancreatic B-cells was calculated by HOMA-B index. Comparison among groups was done by analysis of variance followed by Tukey test. Linear regression analysis of T3 versus HOMA-IR was calculated. IS was reduced in all types of SCTox when compared with C. All SCTox groups had significantly higher levels of insulin (baseline and postmeal) and HOMA-IR and lower values of QUICKI and Aloulou when compared with controls. SCTox-Endog, however, had higher baseline insulin levels and HOMA-IR and a lower QUICKI index than the rest of the SCTox groups. Although within the normal range, total T4, free T4, and T3 levels were also significantly higher in the SCTox groups than in euthyroids. In SCTox-Endog, T3/T4 ratio was increased above the rest of SCTox groups. A moderate linear relationship between T3 and HOMA-IR was found in the whole population. IR is associated with SCTox of either endogenous or exogenous origin. However, based on our findings of lower IS compared with the rest of the SCTox groups, the endogenous subclinical form might have an even larger metabolic impact.

Serum vaspin levels in normal pregnancy in comparison with non-pregnant women

Pregnancy represents a state of insulin resistance (IR). Vaspin (SERPINA12) is a novel insulin-sensitizing adipokine that might be implicated in endogenous glucose regulation. However, its role in pregnancy and its circulating levels have not been adequately studied. We aimed to evaluate serum vaspin levels in pregnancy and their correlation with known markers of IR. A group of 106 women (age 27.9±0.4 years) at the 24-30th week of gestation (pregnancy group) and another 106 age-matched healthy non-pregnant controls (control group) were included in the study. Serum glucose, insulin, vaspin, adiponectin, and lipid parameters were measured. The quantitative insulin sensitivity check index (QUICKI) was used as an insulin sensitivity index. Pregnant women had significantly higher body mass index (BMI), lipids, and serum insulin and lower serum glucose and vaspin levels than controls. Vaspin was positively correlated to adiponectin in both groups (P<0.001 and P<0.004 respectively) but was not correlated to BMI, serum insulin levels, or the QUICKI index in either group. Furthermore, vaspin was negatively correlated to lipid parameters (total cholesterol, triglycerides, and low-density lipoproteins) in the pregnant but not in the non-pregnant women. Vaspin cannot serve as a marker of IR in either pregnant or non-pregnant women, although it is significantly correlated with adiponectin. On the other hand, vaspin might be useful as a surrogate marker of lipid metabolism in pregnancy if confirmed by subsequent studies.

Glucose Metabolism in Overweight Hispanic Adolescents With and Without Polycystic Ovary Syndrome

About one third of overweight women with polycystic ovary syndrome (PCOS) have either impaired glucose tolerance (IGT) or type 2 diabetes mellitus (DM) by the age of 30. We sought to determine if overweight Hispanic adolescents with PCOS are more likely to be insulin resistant and glucose intolerant than those without PCOS. A retrospective chart review of 101 subjects with PCOS and 40 without PCOS was conducted. Homeostasis Model Assessment of Insulin Resistance (HOMA-IR), Quantitative Insulin Sensitivity Check Index (QUICKI), and fasting glucose/insulin ratio (FGIR) values were calculated by using fasting glucose and insulin levels. Insulin resistance (IR) was defined as a fasting insulin level of >15 microU/mL, a 2-hour insulin level of >75 microU/mL, a HOMA-IR value of >3.16, a QUICKI value of <0.357, and/or a FGIR value of <7. Of the 101 overweight subjects with PCOS (BMI: 33.2 +/- 5.9 kg/m(2)), 4 had IGT and 2 had DM versus none of the 40 subjects without PCOS (BMI: 32.4 +/- 5.3 kg/m(2)). IR was more frequent in the overweight PCOS than in the overweight non-PCOS group (QUICKI: 68.4% vs 14.3%, P = .014) and FGIR (47.4% vs 0%, P = .024). Of the 6 subjects with glucose intolerance, only the QUICKI value was abnormal in all. This retrospective study demonstrated that overweight Hispanic adolescents with PCOS had more IR, IGT and DM than their non-PCOS counterparts. As the QUICKI Index was abnormal in all subjects with IGT and DM, we suggest its use as the first step in deciding which overweight Hispanic adolescents with PCOS should be further tested with an OGTT.

The triglyceride/HDL-cholesterol ratio as a marker of cardiovascular risk in obese children; association with traditional and emergent risk factors

To determine the presence of traditional and emergent cardiovascular risk factors and to evaluate the triglyceride/high-density lipoprotein cholesterol (Tg/HDL-C) ratio as a marker for cardiovascular disease and metabolic syndrome (MS) in obese children. Sixty-seven prepubertal children of both sexes, between the ages of 6 and 12 yr, 20 normal-weight children, 18 overweight, and 29 obese subjects, were studied. Anthropometric measures, blood pressure, body mass index (BMI), and fat mass (FM), were measured. Plasma glucose, serum insulin, lipid profile, C-reactive protein (CRP), and leptin concentrations were quantified. Glucose and insulin concentrations 2 h post-glucose load were determined. The Tg/HDL-C ratio, homeostasis model assessment index (HOMA), and quantitative insulin sensitivity check index (QUICKI) were calculated. Systolic, diastolic, and mean blood pressures (MBP), low-density lipoprotein cholesterol (LDL-C), Tg/HDL-C, total cholesterol/HDL-C, LDL-C/HDL-C ratios, basal and 2 h postload insulin, CRP, and leptin were significantly higher and the QUICKI index were lower in the obese group. MBP, Tg/HDL-C ratio, HOMA, CRP, and leptin levels showed a positive and significant correlation and QUICKI a negative correlation with abdominal circumference, BMI, and FM. The Tg/HDL-C ratio correlated positively with MBP. The frequency of MS in the obese group was 69%. While Tg/HDL-C ratio, CRP, and leptin were higher and the values of QUICKI were lower in subjects with MS, it was the Tg/HDL-C ratio and the BMI that significantly explained the MS. Obesity increases the cardiovascular risk in childhood. The Tg/HDL-C ratio could be a useful index in identifying children at risk for dyslipidemia, hypertension, and MS.

The effect of cinnamon extract on insulin resistance parameters in polycystic ovary syndrome: a pilot study

Cinnamon extract has been shown to reduce insulin resistance in in vitro and in vivo studies by increasing phosphatidylinositol 3-kinase activity in the insulin signaling pathway and thus potentiating insulin action. Fifteen women with polycystic ovary syndrome (PCOS) were randomized to daily oral cinnamon and placebo for 8 weeks. Comparisons of post-treatment to baseline insulin sensitivity indices using fasting and 2-hour oral glucose tolerance tests showed significant reductions in insulin resistance in the cinnamon group but not in the placebo group. A larger trial is needed to confirm the findings of this pilot study and to evaluate the effect of cinnamon extract on menstrual cyclicity.