Insulinemic potential of lifestyle is associated with depression and anxiety in adults: A large community-based study

BACKGROUND

We aimed to investigate the association between an empirical lifestyle index for hyperinsulinemia (ELIH), empirical lifestyle index for insulin resistance (ELIR), and depression and anxiety in an adult Iranian population.

METHODS

In this cross-sectional study, a total of 6450 participants, aged 35-65 years were recruited as part of the MASHAD cohort study. Dietary intakes were assessed using a validated food frequency questionnaire (FFQ). Depression and anxiety were screened using Beck Depression Inventory (BDI) and Beck Anxiety Inventory (BAI). ELIH and ELIR were calculated using dietary intake, body mass index, and physical activity information. Multivariable ordinal logistic regression models were applied to determine the association between ELIH, ELIR, and depression and anxiety severity.

RESULTS

In a fully adjusted model, participants with the highest ELIH quartile had a higher odds of more severe depression and anxiety compared to those in the lowest category (OR = 1.44; 95 % CI = 1.22-1.71 and OR = 1.62; 95 % CI = 1.37-1.25, respectively). Participants with the highest ELIR had higher odds of more severe depression and anxiety compared to those in the lowest category (OR = 1.22; 95 % CI = 1.04-1.43 and OR = 1.21; 95 % CI = 1.03-1.42, respectively).

LIMITATIONS

The assessment of dietary intake and mental health by questionnaires may increases the rate of misclassification. Due to the study's cross-sectional nature, causal relationships cannot be established.

CONCLUSION

There was a significant positive association between the hyperinsulinemia and insulin resistance potential of lifestyle and severity of depression and anxiety among Iranian adults.

Factors associated with neonatal hyperinsulinemic hypoglycemia, a case-control study

OBJECTIVES

We aimed to identify perinatal risk factors associated with hyperinsulinemic hypoglycemia in neonates. Secondary objectives included an examination of clinical and biochemical characteristics at the time of diagnosis and an exploration of the duration of diazoxide therapy.

METHODS

A case-control study was conducted, involving individual chart reviews of inborn infants diagnosed with hyperinsulinemic hypoglycemia (the HH group) between 2014 and 2021. These cases were paired with controls (the non-HH group) belonging to the same gestational age (GA) strata who did not exhibit HH or only had transient postnatal hypoglycemia.

RESULTS

A total of 52 infants with HH were matched with corresponding controls. The mean GA in the HH group was 34.4 ± 3.1 weeks. Notably, the HH group exhibited lower mean minimum plasma glucose (PG) levels and required higher glucose infusion rates in comparison to the non-HH group (26.5 ± 15.6 vs. 49.1 ± 37.7 mg/dL and 12.9 ± 3.8 vs. 5.7 ± 2.1 mg/kg/min, respectively; p<0.001 for both). After adjusting for potential confounding factors, only two variables, fetal growth restriction (FGR) and neonatal sepsis, demonstrated significant associations with HH (adjusted odds ratio [95 % confidence interval]: 8.1 [2.1-31.0], p=0.002 and 6.3 [1.9-21.4], p=0.003, respectively). The median duration of diazoxide therapy for the HH group was 4 months.

CONCLUSIONS

FGR and neonatal sepsis emerged as notable risk factors for HH. These infants exhibited lower PG levels and necessitated higher glucose infusion rates compared to their non-HH counterparts. Importantly, a substantial proportion of the HH group received diazoxide therapy, with a median treatment duration of 4 months.

Obesity and obesity-associated metabolic disease conditions in Connemara ponies in Ireland

BACKGROUND

Equine obesity combined with insulin dysregulation (ID) is a major risk factor associated with laminitis. Some pony breeds appear to be at increased risk. However, little is known regarding the prevalence of obesity or hyperinsulinaemia as evidence of ID in Irish ponies.

OBJECTIVE

To investigate the prevalence of obesity and associated endocrine/metabolic disease conditions in Connemara ponies and to determine if hyperinsulinaemia in these ponies could be predicted by morphometric or metabolic markers.

STUDY DESIGN

Cross-sectional study.

METHODS

The study population included registered Connemara ponies recruited through public and veterinary social media posts. Ponies underwent a physical examination and information on their management and clinical history was obtained via owner questionnaire. The body condition score (BCS) was measured using the Henneke system; cresty neck score (CNS) and regionalised adiposity were also assessed. Hyperinsulinaemia was confirmed by measuring serum basal insulin concentration (BIC) or insulin concentration after an oral sugar test (OST). Blood glucose and triglyceride concentrations were measured. Characteristics of hyperinsulinaemic and insulin-sensitive ponies were compared by logistic regression.

RESULTS

Two hundred ponies were included; 59 ponies (29.5%) had a BCS ≥7, 58 (29.0%) had a CNS ≥2.5 and 135 (67.5%) had regionalised adiposity; 137 (68.5%) ponies had at least one of these abnormalities. Owner-reported history or clinical evidence of chronic laminitis was found in 92 ponies (46.0%). Hyperinsulinaemia was confirmed in 32 ponies (16.0%), including 23 of 91 (25.3%) detected by OST and 9 of 109 (8.3%) by BIC. Hypertriglyceridaemia was observed in 12 of 198 ponies (6.1%) ponies and hyperglycaemia in 11 of 197 ponies (5.6%) ponies. The odds of hyperinsulinaemia increased by a factor of 6.53 (95% confidence interval: 2.95, 15.21) when BCS was ≥7.

MAIN LIMITATIONS

The OST was not performed in all ponies.

CONCLUSIONS

Increased adiposity, laminitis and metabolic derangements are prevalent in this native Irish pony breed.

Dietary and lifestyle indices for hyperinsulinemia and colorectal cancer risk: a case-control study

BACKGROUND

The incidence of colorectal cancer (CRC) has increased in Iran, and determining the dietary patterns that can contribute to reducing or increasing the risk of CRC will help better control this disease. Therefore, in the current study, we assessed the association between the empirical lifestyle index for hyperinsulinemia (ELIH) and the empirical dietary index for hyperinsulinemia (EDIH) with the CRC odds.

METHODS

The present case (n = 71)-control (n = 142) study was carried out in several CRC surgical units of hospitals in Tehran, Iran. A semi-quantitative food frequency questionnaire containing 168 items was used to assess participants' dietary intakes. The EDIH and ELIH scores were calculated by food groups and some variables such as body mass index and physical activity. Logistic regression models were applied to evaluate the association between the EDIH and ELIH scores with CRC odds.

RESULTS

According to baseline features of the study participants, there were significant differences between the controls and cases in ELIH score, fiber intake, taking aspirin, and family history of CRC in first- and second-degree relatives. Also, we found that the odds of CRC increased significantly in the last tertile compared to the first tertile in EDIH and ELIH in the adjusted model (odds ratio (OR) = 3.12; 95% confidence interval (CI): 1.30-7.48 and OR = 4.72; 95% CI: 1.15-19.39, respectively).

CONCLUSIONS

In conclusion, the result of this study indicated that CRC odds was significantly greater in subjects with higher EDIH and ELIH scores. Also, according to the results of this study, lifestyle and diet with insulinemic potential can influence the CRC risk.

The Rising Incidence of Hyperinsulinemic Hypoglycemia: Connection With Maternal Health

OBJECTIVE

Due to a perceived rise in hyperinsulinemic hypoglycemia (HH) cases over time, notably during the COVID-19 pandemic, institutional experiences between 2013 and 2021 were reviewed to evaluate trends, characteristics, and outcomes in children with HH.

METHODS

Charts of all children diagnosed with HH during the study period and evaluated by Pediatric Endocrinology were reviewed. HH was defined per Pediatric Endocrine Society guidelines. Regression analysis compared rates of change in HH cases and maternal risk factors over time.

RESULTS

The incidence of HH began to rise in April 2016 and became significant in March 2017 (P < .001), with a more rapid rate of rise during the first year of the COVID-19 pandemic (P < .001). Seventy-four children with HH were identified over 9 years; 43% (n = 32) were diagnosed in 2020-2021. Maternal hypertensive disorders demonstrated longitudinal association with hyperinsulinism cases (P < .001).

CONCLUSION

While HH diagnoses were on the rise for much of the 9-year study period, nearly half of all infants were diagnosed during the COVID-19 pandemic in 2020 to 21. The trends in HH diagnoses correlated with maternal hypertensive disorders. More studies exploring the roles of maternal health, hypertension, and stress and development of HH in offspring are needed.

The Relationship between Insulin Resistance and Thyroid Volume in Georgia

Patients with insulin resistance (IR) have a higher thyroid volume therefore the aim of our study is to examine the correlation between IR and thyroid volume in the residents of Georgia.

METHODS

413 patients with a mean age of 37.3 ± and 11.4 years were included in this study. Out of those, 120 were males, and 293 were females who were studied retrospectively. They had hyperinsulinemia and were referred to the clinic from 2017 to 2019. The factors studied were age, sex, body mass index (BMI), clinical signs, thyroid ultrasound, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lipids, fasting insulin, fasting glucose, thyroid stimulating hormone (TSH), Free thyroxine (FT4), and Zinc (Zn).

RESULTS

IR was detected in 252 individuals. The frequency of men with insulin resistance was significantly higher than in the control group - 72.50%, and 56.31%, respectively (F = 9.55, p= 0.0021). Mean thyroid volume in the patients with IR was significantly higher compared to the controls 20.52 + 6.39 cm3 and 15.25 + 6.55 cm3, respectively (p < 0.001). Hyperinsulinemia had a significant positive correlation with Goiter r = 0.445, p < 0.0001. The associated factors for hyperinsulinemia are: Goiter (1) - OR = 5.12 (95% CI:3.02-8.69); Cholesterol - OR = OR = 3.31 (95% CI: 1.54-7.14); Triglycerides - OR = 3.23 (95% CI:1.02-10.28); Obesity (1)- OR = 3.94 (95% CI: 2.23-6.98); Thyroid structural changes (1) - OR = 2.01 (95% CI: 1.12-3.60); ALT/AST-OR = 4.53 (95% CI: 2.33-8.80); Zn decreased Odds Ratio hyperinsulinemia - OR = 0.95 (95% CI: 0.94-0.97).

CONCLUSION

Hyperinsulinemia is the most common cause of diffuse goiter and the heterogeneous structure of the thyroid. The volume of the thyroid gland shows a significant positive association with the characteristics of metabolic syndrome and increased thyroid volume predictors of metabolic syndrome.

Lipoprotein(a) and Hyperinsulinemia in Healthy Normal-weight, Prepubertal Mexican Children

Background. Given the numerous gaps in our knowledge about the biological interactions of lipoprotein(a) [Lp(a)], we determined whether Lp(a) was associated with hyperinsulinemia in healthy normal-weight, prepubertal children.Methods. A total of 131 healthy normal-weight Mexican children aged 6 to 9 years at Tanner stage 1 who were born appropriate for gestational age were enrolled in a case-control study. Children with hyperinsulinemia were allocated into the case group (n = 32), and children with normal insulin levels were allocated into the control group (n = 99). Birth weight, age, and body mass index were matching criteria. Multivariate logistic regression analysis was used to compute the odds ratio (OR) between Lp(a) and both hyperinsulinemia and insulin resistance. Furthermore, a multivariate linear regression analysis was performed to evaluate the association between Lp(a) and both insulin levels and HOMA-IR. Both models were adjusted by sex, age, birth weight, and body mass index.Results. The median (25-75 percentile) serum levels of Lp(a) [20.0 (13.7-29.6) versus 14.6 (10.6-26.7) mg/dL, p = .003] and insulin [24.5 (6.0-30) versus 7.9 (4.3-9.0) µU/L, p < .0005] were higher in the case group than in the control group. The logistic regression analysis showed that Lp(a) was associated with hyperinsulinemia (OR 5.86; 95%CI 2.5-13.6, p < .0005) and insulin resistance (OR 2.01; 95%CI 1.1-9.9, p = .004). In addition, the linear regression analysis showed a significant association between serum Lp(a) and insulin levels (β 11.1; 95%CI 1.8-10.9, p < .0001) and the HOMA-IR index (β 2.606; 95%CI 2.3-2.9, p < .0005).Conclusion. Lp(a) was associated with hyperinsulinemia and insulin resistance in healthy normal-weight, prepubertal children.

Determinants of hepatic insulin clearance - Results from a Mendelian Randomization study

AIMS/HYPOTHESIS

Besides insulin resistance, type 2 diabetes associates with decreased hepatic insulin clearance (HIC). We now tested for causal relationship of HIC to liver fat accumulation or features of the metabolic syndrome.

METHODS

HIC was derived from oral glucose tolerance tests with the "Oral C-peptide and Insulin Minimal Models" (n = 3311). Liver fat was quantified by magnetic resonance spectroscopy (n = 1211). Mendelian Randomization was performed using established single nucleotide polymorphisms (SNPs; 115 for liver fat, 155 alanine-aminotransferase, 37 insulin sensitivity, 37 insulin secretion, 72 fasting insulin, 5285 BMI, 163 visceral fat, 270 waist circumference, 442 triglycerides, 620 HDL-Cholesterol, 193 C-reactive protein, 53 lipodystrophy-like phenotypes).

RESULTS

HIC associated inversely with liver fat (p < 0.003) and insulin sensitivity (p < 0.0001). Both liver fat and HIC were independently associated with insulin sensitivity (p < 0.0001). Neither liver fat nor alanine-aminotransferase were causally linked to HIC, as indicated by Mendelian Randomization (N_{liver fat} = 1054, N_HIC = 2254; N_{alanineaminotranferase} = 1985, N_HIC = 2251). BMI-related SNPs were causally associated with HIC (N_BMI = 2772, N_HIC = 2259, p < 0.001) but not waist circumference-SNPs (N_{SNPs-waist circumference} = 2751, N_HIC = 2280). Genetically determined insulin sensitivity was not causally related to HIC (N_{insulin sensitivity} = 2752, N_HIC = 2286). C-reactive protein and HDL were causally associated with HIC, with higher C-reactive protein and lower HDL leading to higher HIC (N_{C-reactive protein} = 2660, N_HIC = 2240; N_HDL = 2694, N_HIC = 2275).

CONCLUSIONS

This Mendelian Randomization analysis does not support a causal link between hepatic steatosis and HIC. Other components of the metabolic syndrome seem to compensate peripheral hyperinsulinemia by increasing hepatic insulin extraction.

Bidirectional temporal relationship between obesity and hyperinsulinemia: longitudinal observation from a Chinese cohort

INTRODUCTION

Although obesity and hyperinsulinemia are closely intercorrelated, their temporal sequence is still uncertain. This study aims to investigate the temporal relationship patterns between obesity measures and hyperinsulinemia in Chinese adults.

RESEARCH DESIGN AND METHODS

The longitudinal cohort consisted of 2493 participants (860 males and 1633 female, mean age 56.71 years at follow-up) for whom measurements of obesity and hyperinsulinemia measures were collected twice between 2011 and 2014, with an average follow-up time of 3 years. Cross-lagged panel analysis was used to examine the temporal relationship between obesity measures (body mass index (BMI); waist circumference (WC); hip circumference (HC); waist-to-hip ratio (WHR)) and hyperinsulinemia (insulin, homeostasis model assessment of insulin resistance (HOMA-IR), or homeostasis model assessment of beta cell function (HOMA-%β)).

RESULTS

After the adjustment of age, sex, smoking, drinking and follow-up years, in the BMI-insulin model, the path coefficient (β₂=0.229; p<0.001) of baseline BMI to follow-up insulin was significantly greater than the path coefficient (β₁=0.073; p<0.001) of baseline insulin to follow-up BMI (p<0.001 for β₂>β₁). In the WHR-insulin model, the path coefficient (β₁=0.152; p<0.001) of baseline insulin to follow-up WHR was significantly greater than the path coefficient (β₂=0.077; p<0.001) of baseline WHR to follow-up insulin (p=0.007 for β₁>β₂). In the WC/HC-insulin model, the path coefficients of baseline insulin to follow-up WC or HC (β_1s) were also greater than the path coefficients of baseline WC or HC to follow-up insulin (β_2s), but the difference between β_1s and β_2s were not significant. The similar temporal patterns were founded between obesity measures with HOMA-IR or HOMA-%β.

CONCLUSIONS

These findings indicate that there is a bidirectional relationship between obesity and hyperinsulinemia, and abdominal obesity measures are more sensitive to hyperinsulinemia measures than BMI.

Do variations in insulin sensitivity and insulin secretion in pregnancy predict differences in obstetric and neonatal outcomes?

AIMS/HYPOTHESIS

Gestational diabetes mellitus (GDM) is generally defined based on glycaemia during an OGTT, but aetiologically includes women with defects in insulin secretion, insulin sensitivity or a combination of both. In this observational study, we aimed to determine if underlying pathophysiological defects evaluated as continuous variables predict the risk of important obstetric and neonatal outcomes better than the previously used dichotomised or categorical approaches.

METHODS

Using data from blinded OGTTs at mean gestational week 28 from five Hyperglycemia and Adverse Pregnancy Outcome study centres, we estimated insulin secretion (Stumvoll first phase) and sensitivity (Matsuda index) and their product (oral disposition index [DI]) in 6337 untreated women (1090 [17.2%] with GDM as defined by the International Association of Diabetes and Pregnancy Study Groups). Rather than dichotomising these variables (i.e. GDM yes/no) or subtyping by insulin impairment, we related insulin secretion and sensitivity as continuous variables, along with other maternal characteristics, to obstetric and neonatal outcomes using multiple regression and receiver operating characteristic curve analysis.

RESULTS

Stratifying by GDM subtype offered superior prediction to GDM yes/no only for neonatal hyperinsulinaemia and pregnancy-related hypertension. Including the DI and the Matsuda score significantly increased the area under the receiver operating characteristic curve (AUROC) and improved prediction for multiple outcomes (large for gestational age [AUROC 0.632], neonatal adiposity [AUROC 0.630], pregnancy-related hypertension [AUROC 0.669] and neonatal hyperinsulinaemia [AUROC 0.688]). Neonatal hypoglycaemia was poorly predicted by all models. Combining the DI and the Matsuda score with maternal characteristics substantially improved the predictive power of the model for large for gestational age, neonatal adiposity and pregnancy-related hypertension.

CONCLUSION/INTERPRETATION

Continuous measurement of insulin secretion and insulin sensitivity combined with basic clinical variables appeared to be superior to GDM (yes/no) or subtyping by insulin secretion and/or sensitivity impairment in predicting obstetric and neonatal outcomes in a multi-ethnic cohort. Graphical abstract.

Metabolomics analysis reveals altered metabolites in lean compared with obese adolescents and additional metabolic shifts associated with hyperinsulinaemia and insulin resistance in obese adolescents: a cross-sectional study

INTRODUCTION

Hyperinsulinaemia and insulin resistance (IR) are strongly associated with obesity and are forerunners of type 2 diabetes. Little is known about metabolic alterations separately associated with obesity, hyperinsulinaemia/IR and impaired glucose tolerance (IGT) in adolescents.

OBJECTIVES

To identify metabolic alterations associated with obesity, hyperinsulinaemia/IR and hyperinsulinaemia/IR combined with IGT in obese adolescents.

METHODS

81 adolescents were stratified into four groups based on body mass index (lean vs. obese), insulin responses (normal insulin (NI) vs. high insulin (HI)) and glucose responses (normal glucose tolerance (NGT) vs. IGT) after an oral glucose tolerance test (OGTT). The groups comprised: (1) healthy lean with NI and NGT, (2) obese with NI and NGT, (3) obese with HI and NGT, and (4) obese with HI and IGT. Targeted nuclear magnetic resonance-based metabolomics analysis was performed on fasting and seven post-OGTT plasma samples, followed by univariate and multivariate statistical analyses.

RESULTS

Two groups of metabolites were identified: (1) Metabolites associated with insulin response level: adolescents with HI (groups 3-4) had higher concentrations of branched-chain amino acids and tyrosine, and lower concentrations of serine, glycine, myo-inositol and dimethylsulfone, than adolescents with NI (groups 1-2). (2) Metabolites associated with obesity status: obese adolescents (groups 2-4) had higher concentrations of acetylcarnitine, alanine, pyruvate and glutamate, and lower concentrations of acetate, than lean adolescents (group 1).

CONCLUSIONS

Obesity is associated with shifts in fat and energy metabolism. Hyperinsulinaemia/IR in obese adolescents is also associated with increased branched-chain and aromatic amino acids.

The triglyceride/glucose ratio is a reliable index of fasting insulin resistance: Observations from hyperinsulinaemic-euglycaemic clamp studies in young, normoglycaemic males from southern India

BACKGROUND & AIMS

Non-obese Asians have a high propensity to develop insulin resistance. Therefore, screening such individuals for insulin resistance using simple surrogate indices is important. In this study, we aimed to validate the triglyceride-glucose (Tg/glu) ratio against the M value of hyperinsulinaemic-euglycaemic clamp (HEC) procedure and other surrogate indices of insulin resistance in normoglycaemic Indian males from Southern India.

METHODS

A cohort of 105 normoglycaemic males (mean BMI: 19.2 ± 2.6 kg/m²) underwent HEC procedure. Surrogate indices of insulin resistance viz. the triglyceride-glucose (Tg/Glu) ratio, the triglyceride-glucose index, the McAuley's index, the HOMA-IR, the QUICKI, the fasting glucose to insulin ratio (FG-IR), and the fasting C- peptide index were calculated and correlated with the M value. The cut-off value for the Tg/Glu ratio was obtained using the Receiver Operator Characteristics (ROC) with Area under curve (AUC) analysis at 95% confidence interval (CI). The P value < 0.05 was considered statistically significant.

RESULTS

The Tg/Glu ratio demonstrated significantly higher AUC (0.81), when compared to the Tg × glu index (0.63), 20/fasting C peptide × fasting plasma glucose index (0.55), HOMA-IR (0.47), QUICKI (0.26), FGIR (0.12) and McAuley's index (0.18). For the Tg/Glu ratio, a cut-off value ≥ 1.19 had high sensitivity (80%) and specificity (79%) values (PPV: 16%; NPV: 98.8%) respectively.

CONCLUSION

The Tg/Glu ratio can be used as a reliable surrogate index to screen for risk of insulin resistance in lean, normoglycaemic males from Southern India.

Glycemic Status, Insulin Resistance, and Risk of Pancreatic Cancer Mortality in Individuals With and Without Diabetes

INTRODUCTION

The impact of glycemic status and insulin resistance on the risk of pancreatic cancer in the nondiabetic population remains uncertain. We aimed to examine the association of glycemic status and insulin resistance with pancreatic cancer mortality in individuals with and without diabetes.

METHODS

This is a cohort study of 572,021 Korean adults without cancer at baseline, who participated in repeat screening examinations which included fasting blood glucose, hemoglobin A1c, and insulin, and were followed for a median of 8.4 years (interquartile range, 5.3 -13.2 years). Vital status and pancreatic cancer mortality were ascertained through linkage to national death records.

RESULTS

During 5,211,294 person-years of follow-up, 260 deaths from pancreatic cancer were identified, with a mortality rate of 5.0 per 10 person-years. In the overall population, the risk of pancreatic cancer mortality increased with increasing levels of glucose and hemoglobin A1c in a dose-response manner, and this association was observed even in individuals without diabetes. In nondiabetic individuals without previously diagnosed or screen-detected diabetes, insulin resistance and hyperinsulinemia were positively associated with increased pancreatic cancer mortality. Specifically, the multivariable-adjusted hazard ratio (95% confidence intervals) for pancreatic cancer mortality comparing the homeostatic model assessment of insulin resistance ≥75th percentile to the <75th percentile was 1.49 (1.08-2.05), and the corresponding hazard ratio comparing the insulin ≥75th percentile to the <75th percentile was 1.43 (1.05-1.95). These associations remained significant when introducing changes in insulin resistance, hyperinsulinemia, and other confounders during follow-up as time-varying covariates.

DISCUSSION

Glycemic status, insulin resistance, and hyperinsulinemia, even in individuals without diabetes, were independently associated with an increased risk of pancreatic cancer mortality.

Hyperinsulinaemia in cancer

Elevated circulating insulin levels are frequently observed in the setting of obesity and early type 2 diabetes, as a result of insensitivity of metabolic tissues to the effects of insulin. Higher levels of circulating insulin have been associated with increased cancer risk and progression in epidemiology studies. Elevated circulating insulin is believed to be a major factor linking obesity, diabetes and cancer. With the development of targeted cancer therapies, insulin signalling has emerged as a mechanism of therapeutic resistance. Although metabolic tissues become insensitive to insulin in the setting of obesity, a number of mechanisms allow cancer cells to maintain their ability to respond to insulin. Significant progress has been made in the past decade in understanding the insulin receptor and its signalling pathways in cancer, and a number of lessons have been learnt from therapeutic failures. These discoveries have led to numerous clinical trials that have aimed to reduce the levels of circulating insulin and to abrogate insulin signalling in cancer cells. With the rising prevalence of obesity and diabetes worldwide, and the realization that hyperinsulinaemia may contribute to therapeutic failures, it is essential to understand how insulin and insulin receptor signalling promote cancer progression.

Relationships between hyperinsulinaemia, magnesium, vitamin D, thrombosis and COVID-19: rationale for clinical management

Risk factors for COVID-19 patients with poorer outcomes include pre-existing conditions: obesity, type 2 diabetes mellitus, cardiovascular disease (CVD), heart failure, hypertension, low oxygen saturation capacity, cancer, elevated: ferritin, C reactive protein (CRP) and D-dimer. A common denominator, hyperinsulinaemia, provides a plausible mechanism of action, underlying CVD, hypertension and strokes, all conditions typified with thrombi. The underlying science provides a theoretical management algorithm for the frontline practitioners.Vitamin D activation requires magnesium. Hyperinsulinaemia promotes: magnesium depletion via increased renal excretion, reduced intracellular levels, lowers vitamin D status via sequestration into adipocytes and hydroxylation activation inhibition. Hyperinsulinaemia mediates thrombi development via: fibrinolysis inhibition, anticoagulation production dysregulation, increasing reactive oxygen species, decreased antioxidant capacity via nicotinamide adenine dinucleotide depletion, haem oxidation and catabolism, producing carbon monoxide, increasing deep vein thrombosis risk and pulmonary emboli. Increased haem-synthesis demand upregulates carbon dioxide production, decreasing oxygen saturation capacity. Hyperinsulinaemia decreases cholesterol sulfurylation to cholesterol sulfate, as low vitamin D regulation due to magnesium depletion and/or vitamin D sequestration and/or diminished activation capacity decreases sulfotransferase enzyme SULT2B1b activity, consequently decreasing plasma membrane negative charge between red blood cells, platelets and endothelial cells, thus increasing agglutination and thrombosis.Patients with COVID-19 admitted with hyperglycaemia and/or hyperinsulinaemia should be placed on a restricted refined carbohydrate diet, with limited use of intravenous dextrose solutions. Degree/level of restriction is determined by serial testing of blood glucose, insulin and ketones. Supplemental magnesium, vitamin D and zinc should be administered. By implementing refined carbohydrate restriction, three primary risk factors, hyperinsulinaemia, hyperglycaemia and hypertension, that increase inflammation, coagulation and thrombosis risk are rapidly managed.

Nationwide survey of endogenous hyperinsulinemic hypoglycemia in Japan (2017-2018): Congenital hyperinsulinism, insulinoma, non-insulinoma pancreatogenous hypoglycemia syndrome and insulin autoimmune syndrome (Hirata's disease)

AIMS/INTRODUCTION

We aimed to investigate the nationwide incidence, treatment details and outcomes of patients with endogenous hyperinsulinemic hypoglycemia (EHH), including those with transient/persistent congenital hyperinsulinism (CHI), insulinoma, non-insulinoma pancreatogenous hypoglycemia syndrome and insulin autoimmune syndrome (Hirata's disease) in Japan.

MATERIALS AND METHODS

A nationwide, questionnaire-based survey was carried out to determine the number of patients with EHH who were treated for hypoglycemia or hypoglycemia-related complications in 2017-2018. The questionnaires were sent to all hospitals in Japan with >300 beds, and with pediatric and/or adult clinics likely managing EHH patients. The secondary questionnaires were sent to obtain the patients' date of birth, sex, age at onset, treatment details and post-treatment outcomes.

RESULTS

A total of 447 patients with CHI (197 transient CHI, 225 persistent CHI and 25, unknown histology), 205 with insulinoma (118 benign, 18 malignant and 69 unknown subtype), 111 with non-insulinoma pancreatogenous hypoglycemia syndrome (33 post-gastric surgery HH, 57 postprandial HH, 10 nesidioblastosis and 11 unknown subtype) and 22 with insulin autoimmune syndrome were identified. Novel findings included: (i) marked improvement in the prognosis of persistent CHI over the past 10 years; (ii) male dominance in the incidence of transient CHI; (iii) non-insulinoma pancreatogenous hypoglycemia syndrome emerging as the second most common form of EHH in adults; (iv) frequent association of diabetes mellitus with insulin autoimmune syndrome; and (v) frequent post-treatment residual hypoglycemia and impaired quality of life.

CONCLUSIONS

The first nationwide, all age group survey of EHH showed the current status of each type of EHH disorder and the unmet needs of the patients.

Relationship between serum insulin and point-of-admission blood glucose of ill neonates at a tertiary health facility in Nigeria

Introduction

Optimal glucose metabolism is important in neonatal survival especially in the first days of life. Insulin play a significant role in maintaining blood glucose homeostasis. This study set out to determine the serum insulin levels of ill neonates as related to their point-of-admission blood glucose estimation at the Wesley Guild Hospital, Ilesa, Nigeria.

Methods

Three hundred babies took part in the study. Blood glucose and serum insulin levels were assayed at admission using Accu-Chek Active glucometer^(R) and Accu-Ɔ-Bind ELISA Microwells^(R) respectively. Hyperglycaemia was defined as blood glucose ≥7mmol/L and hypoglycaemia as blood glucose <2.2mmol/L.

Results

The median (IQR) age of the babies was 10.0 (0.5 - 70.0) hours with male to female ratio of 1.5:1. Seventy-four (24.7%) were preterms and 35 (11.7%) were small-for-gestational age. The mean (SD) blood glucose level of the babies was 4.1(2.1) mmol/L with a range of 0.6-13.4mmol/L. Hyperglycaemia and hypoglycaemia were observed in 18(6.0%) and 40(13.3%) babies respectively. The median (IQR) serum insulin level was 9.8(3.0-35.3) μIU/ml. There was weak positive correlation between serum insulin and blood glucose levels of the babies (r = 0.197, p = 0.001). Birth asphyxia was associated with lower serum insulin, while probable sepsis with relatively higher levels.

Conclusion

Serum insulin level increases with increasing blood glucose in ill Nigerian babies at presentation to the hospital. Babies with asphyxia and sepsis particularly tend to have abnormal serum insulin at admission. Hyperinsulinaemia in ill babies may connote a compensatory mechanism to normalise abnormal blood glucose rather than playing significant role in its aetio-pathogenesis.

Reduced Insulin Clearance and Insulin-Degrading Enzyme Activity Contribute to Hyperinsulinemia in African Americans

BACKGROUND

African Americans (AAs) are at a higher risk for developing type 2 diabetes compared with non-Hispanic whites (NHWs). The causal role of β-cell glucose sensitivity (β-GS) and insulin clearance in hyperinsulinemia in AA adults is unclear.

OBJECTIVE

Using a cross-sectional study design, we compared β-cell function and insulin clearance in nondiabetic AAs (n = 36) and NHWs (n = 47) after a mixed meal test (MMT).

METHODS

Insulin secretion rate, glucose sensitivity, rate sensitivity, and insulin sensitivity during MMT were derived from a mathematical model. Levels of insulin-degrading enzyme (IDE) and carcinoembryonic antigen-related cell adhesion molecule-1 (CEACAM1), key players in insulin clearance, were measured (by enzyme-linked immunosorbent assay) in hepatic cytosolic fractions from age-, sex-, and body mass index-matched AA and NHW cadaveric donors (n = 10).

RESULTS

Fasting and mean postprandial plasma glucose levels were similar in both ethnic groups. AAs had significantly higher fasting and mean postprandial plasma insulin levels. However, fasting ISR, total insulin output, and insulin sensitivity during MMT were not different between the groups. β-GS and rate sensitivity were higher in AAs. Fasting and meal plasma insulin clearance were lower in AAs. Hepatic levels of IDE and CEACAM-1 were similar in AAs and NHWs. Hepatic IDE activity was significantly lower in AAs.

CONCLUSIONS

In this study, lower insulin clearance contributes to higher plasma insulin levels in AAs. Reduced insulin clearance may be explained by lower IDE activity levels in AAs. Further confirmatory studies are needed to investigate diminished insulin clearance in AAs as a result of lower IDE activity levels.

Postprandial Dyslipidemia, Hyperinsulinemia, and Impaired Gut Peptides/Bile Acids in Adolescents with Obesity

BACKGROUND

With increased rates of obesity and insulin resistance in youth, development of postprandial dyslipidemia, an important cardiovascular disease risk factor, is a concern. Glucagon-like peptides (ie, GLP-1 and GLP-2) and bile acids have been shown to regulate dietary fat absorption and postprandial lipids in animal models and humans. We hypothesize that the physiological response of GLPs and bile acids to dietary fat ingestion is impaired in adolescents with obesity and this associates with marked postprandial dyslipidemia and insulin resistance.

METHODS

In this cross-sectional study, normal weight adolescents and adolescents with obesity underwent a 6-hour oral fat tolerance test. The postprandial lipoprotein phenotype profile was determined using various assays, including nuclear magnetic resonance spectroscopy, to characterize lipoprotein particle number, size, lipid content, and apolipoproteins. GLP-1 and GLP-2 were quantified by electrochemiluminescent immunoassays. Total bile acids were measured by an automated enzymatic cycling colorimetric method and the bile acid profile by mass spectrometry.

RESULTS

Adolescents with obesity exhibited fasting and postprandial dyslipidemia, particularly augmented postprandial excursion of large triglyceride-rich lipoproteins. Postprandial GLPs were reduced and inversely correlated with postprandial dyslipidemia and insulin resistance. Postprandial bile acids were also diminished, particularly lithocholic acid, a potent stimulator of GLP-1 secretion.

CONCLUSION

Blunted postprandial GLP and bile acid response to dietary fat ingestion strongly associates with marked postprandial dyslipidemia. Further investigation is needed to assess their potential utility as early biomarkers for postprandial dyslipidemia in adolescents with obesity.

Increased Insulin Concentrations During Growth Hormone Treatment in Girls With Turner Syndrome Are Ameliorated by Hormone Replacement Therapy

OBJECTIVE

Turner syndrome (TS) is characterized by complete or partial loss of one sex chromosome and is commonly associated with short stature, metabolic changes (such as central obesity, abnormal glucose tolerance and high triglycerides) and premature ovarian insufficiency (POI). Primary management of TS during childhood and adolescence comprises treatment with human growth hormone (hGH) and, in cases with early loss of ovarian function, hormone replacement therapy (HRT). Given that metabolic parameters are altered when HRT is applied during menopause, we analyzed whether metabolic changes might be positively or negatively affected within 10 years after HRT and/or hGH in girls with TS.

DESIGN

Observational study.

METHODS

Data were collected from the medical records of 31 girls with TS attending two endocrinologic centers in Germany between 2000 and 2020. Descriptive statistics are reported as the mean ± SEM or percentages.

RESULTS

The mean age at first presentation was 99.06 ± 8.07 months, the mean height was 115.8 ± 3.94 cm, and the mean BMI 19.0 ± 0.99 was kg/m². Treatment with hGH was given to 96.8% of the girls, starting at an average age of 99.06 ± 8.70 months, and was continued for 67.53 ± 6.28 months. HRT was administered to 80.6% of all patients and was started at a mean age of 164.4 ± 4.54 months. During the follow-up, we did not observe any significant absolute changes in lipid parameters, but we detected beneficial effects of childhood hGH: significantly lower cholesterol (-0.206/month; p = 0.006), lower low density lipoprotein cholesterol (-0.216/month; p = 0.004), and higher high density lipoprotein cholesterol (+0.095/month; p = 0.048). Insulin concentrations, showed a significant increase attributable to hGH treatment (+0.206/month; p = 0.003), which was ameliorated by concomitant or subsequent HRT (-0.143/month; p = 0.039).

CONCLUSION

Treatment with hGH and HRT is provided to most girls with TS. Metabolic effects are associated with both modalities. Monitoring of metabolic changes appears to be important to detect unfavorable effects, and could guide treatment adjustment and duration.

Temporal relationship between body mass index and triglyceride-glucose index and its impact on the incident of hypertension

BACKGROUND AND AIMS

Obesity and insulin levels can influence each other by metabolism. However, their temporal sequences and influence on hypertension are generally unknown, especially in Chinese adults. Recently, some scholars have proposed that triglycerides-glucose index (TyG) is an important indicator of insulin resistance. The study aims to describe the relationship between body mass index (BMI) and TyG index and its impact on hypertension.

METHODS AND RESULTS

A total of 4081 adults (56.33% women) without antihypertensive, hypoglycemic or lipid-lowering medications were selected for the present study. Measurements of BMI and TyG index were obtained twice from 2012 to 2017. Cross-lagged panel analysis was used to describe the temporal sequences between BMI and TyG index, and the effect of their temporal relationship patterns on hypertension was explored through mediation analysis. After adjusting for confounding factors (age, sex, ethnicity et al.), the cross-lagged path coefficient from baseline BMI to follow-up TyG (ρ₂ = 0.135, P < 0.001) was significantly greater than the path coefficient from baseline TyG to follow-up BMI (ρ₁ = 0.043, P < 0.001), and P < 0.001 for the difference between ρ₁ and ρ₂. Furthermore, the sensitivity analyses between women and men revealed identical findings. In addition, TyG index mediation effect on BMI-hypertension was estimated to be 38.45% (P < 0.001) in total population, 25.24% in women and 57.35% in men.

CONCLUSION

These results provided evidence that the temporal relationship between BMI and insulin resistance is reciprocal and a higher BMI precedes hyperinsulinemia in Chinese adults. This relationship plays an essential role in the development of hypertension, while there is a difference between women and men.

Hyperinsulinemia and thyroid peroxidase antibody in Chinese patients with papillary thyroid cancer

This study aimed to investigate if hyperinsulinemia and/or insulin resistance was correlated with the occurrence of papillary thyroid cancer (PTC) in a group of Chinese patients. 258 inpatients were included in the study. According to the postoperative pathology results, all subjects were divided into PTC (n = 153) and control groups (with benign thyroid nodules, n = 105). Body mass index (BMI), fasting glucose, fasting insulin, homeostasis model assessment of insulin resistance (HOMA-IR), thyroid-stimulating hormone (TSH), FT4, FT3, thyroid peroxidase antibody (TPOAb), thyroglobulin antibody (TGAb), serum uric acid (UA), and lipid levels. Fasting insulin levels, HOMA-IR values, TPOAb levels, serum TSH levels, and serum uric acid levels in the PTC group were higher than those in the control group (p < 0.05). However, no significant differences in age, gender, BMI, history of hypertension, and the levels of fasting plasma glucose, FT3, FT4, TGAb, total cholesterol, triglyceride, low-density lipoprotein, and high-density lipoprotein were observed between the two groups (p > 0.05). After the multiple logistic regression analysis, the occurrence of PTC was positively associated with fasting insulin (odds ratio [OR] = 1.048, 95% confidence interval [CI]: 1.003-1.096, p = 0.037) and TPOAb levels (OR = 1.001, 95% CI: 1.000-1.002, p = 0.032). Moreover, TPOAb level was positively correlated with vague margin (r = 0.126, p = 0.045) and negatively correlated with homogeneous echo (r = -0.179, p = 0.004). However, fasting insulin levels were not correlated with pathological characteristics of PTC. Hyperinsulinemia and higher TPOAb levels might be the risk factors of PTC, but not disease severity in Chinese patients.

Metabolic syndrome and pre-eclampsia

OBJECTIVE

To evaluate the association between different pre-eclampsia (PE) phenotypes and the development of metabolic syndrome postpartum, in order to identify the subgroup of formerly pre-eclamptic women with a worse cardiovascular risk profile requiring tailored postpartum follow-up.

METHODS

This was a cohort study of 1102 formerly pre-eclamptic women in whom cardiovascular and cardiometabolic evaluation was performed at least 3 months postpartum. Women were divided into four subgroups based on PE resulting in delivery before 34 weeks (early-onset (EO)) or at or after 34 weeks (late onset (LO)) of gestation and whether they delivered a small-for-gestational-age (SGA) neonate. Metabolic syndrome was diagnosed as the presence of hyperinsulinemia along with two or more of: body mass index ≥ 30 kg/m² ; dyslipidemia; hypertension; and microalbuminuria or proteinuria. Data were compared between groups using ANOVA after Bonferroni correction. Odds ratios (OR) were calculated using logistic regression to determine the association between metabolic syndrome and the four subgroups. We constructed receiver-operating characteristics curves and computed the area under the curve (AUC) to quantify the ability of different obstetric variables to distinguish between women who developed metabolic syndrome and those who did not.

RESULTS

The prevalence of metabolic syndrome was higher in women with EO-PE and SGA (25.8%) than in those with EO-PE without SGA (14.7%) (OR 2.01 (95% CI, 1.34-3.03)) and approximately five-fold higher than in women with LO-PE with SGA (5.6%) (OR 5.85 (95% CI, 2.60-13.10)). In women with LO-PE, the prevalence of metabolic syndrome did not differ significantly between women with and those without SGA. Multivariate analysis revealed that a history of SGA, a history of EO-PE and systolic blood pressure at the time of screening are the best predictors of developing metabolic syndrome postpartum. The AUC of the model combining these three variables was 74.6% (95% CI, 70.7-78.5%). The probability of the presence of metabolic syndrome was calculated as: P = 1/(1 + e^-LP ), where LP is linear predictor = -8.693 + (0.312 × SGA (yes = 1)) + (0.507 × EO-PE (yes = 1)) + (0.053 × systolic blood pressure).

CONCLUSIONS

The incidence of metabolic syndrome postpartum was associated more strongly with EO-PE in combination with SGA as compared with LO-PE or EO-PE without SGA. Both time of onset of PE and fetal growth affect the risk of metabolic syndrome after a pre-eclamptic pregnancy. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Incentive design to boost health for juveniles with Medicaid coverage: Evidence from a field experiment

Augmenting incentives for juveniles with separate incentives for parents could boost juvenile efforts to reduce BMI. However, financing a parent incentive by reducing the incentives offered to adolescents could attenuate the juvenile response. In a field experiment, Medicaid-covered juveniles enrolled in a cardiac wellness program were randomly assigned to two groups: juveniles in the focused-incentive group received all earned points; juveniles in the split-incentive group split earned points with a parent. The focused-incentive group was 12.8 percentage points more likely to achieve their stipulated goals compared to the split-incentive group at the end of the 3-month active phase of the program. In contrast, members of the split-incentive group outperformed their peers in the focused-incentive group during the second quarter, and the two incentives structures were equally effective at the year-end session. Additional quasi-experimental data indicates that members of both incentivized groups significantly outperformed (focused-incentive group by 8.48 percentage points and split-incentive group by 11.0 percentage points) a pre-experiment (non-incentivized) set of juveniles enrolled in the same program at year-end.

High prevalence of insulin resistance and occurrence prior to hyperinsulinemia threshold among people living with HIV in Pune, India

BACKGROUND

Diabetes prevalence in HIV is not well characterized for India, despite the high burden of both individual diseases. Epidemiology of insulin resistance (IR): a precursor to diabetes, and its associated risk factors are also poorly understood in Asian Indian people living with HIV (PLHIV). We assessed the prevalence of diabetes and IR in Pune, India and the associated risk factors for IR.

METHODS

Cross-sectional analysis of adult (≥18 years) PLHIV receiving care at Byramjee Jeejeebhoy Government Medical College and Sassoon General Hospitals, Pune, India (BJGMC- SGH). Proportions and medians of PLHIV characteristics by diabetes status and IR were described. Homeostatic Model Assessment (HOMA) index value ≥2 was used to define IR. Line of least squares assessed the relationship between IR and hyperinsulinemia. Association between sociodemographic, clinical factors with IR was determined using logistic regression.

RESULTS

Of 485 enrollees, 47% were men, median age was 40 years (IQR: 35-46), median CD4 counts were 389 cells/mm³ (246-609). Thirty-five percent were centrally obese, 75% were adherent to WHO recommended physical activity guidelines. Prevalence of diabetes, prediabetes, IR were 9%, 16% and 38%, respectively. Twenty-nine percent non-diabetics had IR and it occurred much prior to the threshold for hyperinsulinemia. IR was associated with the use of ART drugs (OR: 6.6, 95% CI: 2.9-15.2 and 5.4, 95% CI: 2.2-13.6 for first- and second line ART respectively) and central obesity (OR:1.9, 95% CI: 1.1-3.4).

CONCLUSIONS

One fourth of the study population was diabetic or prediabetic and more than a third had IR. Better understanding of diabetes disease progression in relation to IR and the effect of physical activity on central obesity among Asian Indian PLHIV is mandated.

Contribution of pancreatic α-cell function to insulin sensitivity and glycemic variability in patients with type 1 diabetes

AIMS/INTRODUCTION

To evaluate the contribution of pancreatic α-cell function to the dawn phenomenon, insulin sensitivity, hepatic glucose uptake and glycemic variability in patients with type 1 diabetes.

MATERIALS AND METHODS

In 40 patients with type 1 diabetes, arginine stimulation tests were carried out, and the area under the curve (AUC) of glucagon was measured using radioimmunoassays (AUCglc RIA ) and enzyme-linked immunosorbent assays (AUCglc ELISA ). The ratio of the insulin dose delivered by an artificial pancreas to maintain euglycemia between 04.00 and 08.00 hours or between 00.00 and 04.00 hours was measured as the dawn index. The glucose infusion rate and hepatic glucose uptake were measured using hyperinsulinemic euglycemic clamp and clamp oral glucose loading tests. Glycemic variability in 96 h was measured by continuous glucose monitoring.

RESULTS

The median dawn index (1.7, interquartile range 1.0-2.8) was not correlated with AUCglc RIA (R2  = 0.03, P = 0.39) or AUCglc ELISA (R2  = 0.04, P = 0.32). The median glucose infusion rate (7.3 mg/kg/min, interquartile range 6.4-9.2 mg/kg/min) was significantly correlated with AUCglc RIA (R2  = 0.20, P = 0.02) and AUCglc ELISA (R2  = 0.21, P = 0.02). The median hepatic glucose uptake (65.3%, interquartile range 40.0-87.3%) was not correlated with AUCglc RIA (R2  = 0.07, P = 0.26) or AUCglc ELISA (R2  = 0.26, P = 0.79). The standard deviation of glucose levels measured by continuous glucose monitoring was significantly correlated with AUCglc RIA (R2  = 0.11, P = 0.049), but not with AUCglc ELISA (R2  = 0.01, P = 0.75).

CONCLUSIONS

Pancreatic α-cell function contributed to insulin sensitivity in patients with type 1 diabetes.

Association between vitamin D deficiency and insulin resistance markers in euthyroid non-diabetic individuals

AIM

To evaluate the association between vitamin D deficiency and insulin resistance (IR) or hyperinsulinemia after oral glucose tolerance test (OGTT) in euthyroid non-diabetic individuals.

MATERIALS AND METHODS

We carried out an analytical cross-sectional study in euthyroid non-diabetic adults of both sexes, who attended the outpatient service of a private clinic in Lima-Peru during the 2012-2016 period. Participants were categorized in two groups according to their serum vitamin D levels: normal vitamin D levels (serum vitamin D values ≥ 20 ng/dL) and vitamin D deficiency (serum vitamin D values < 20 ng/dL). IR was defined as a Homeostasis Model Assessment (HOMA-IR) value ≥ 3.8 and hyperinsulinemia after OGTT was defined as a serum insulin value ≥ 80μU/mL after 120 min of 75-g glucose intake. We elaborated crude and adjusted Poisson regression models to assess the association between serum vitamin D levels and IR or hyperinsulinemia after OGTT. The reported association measure was the prevalence ratio (PR) with their respective 95% confidence intervals (95%CI).

RESULTS

We analyzed 204 participants, the average age was 38.5 ± 10.6 (SD) years, 40 (19.6%) were males and the vitamin D median was 25.0 (IQR: 19.0-33.3) ng/dL. The prevalence of vitamin D deficiency, IR and hyperinsulinemia after OGTT was 29.4% (n = 60), 29.9% (n = 61) and 25.0% (n = 51). In the adjusted Poisson regression models, the prevalence of hyperinsulinemia after OGTT was higher among the vitamin D deficient group (aPR=1.75; 95%CI: 1.06-2.90); however, we did not find statistically significant association between vitamin D deficiency and IR (aPR=0.99; 95%CI: 0.61-1.63).

CONCLUSIONS

We found an association between vitamin D deficiency and hyperinsulinemia after OGTT in euthyroid people with no T2DM.Our findings are consistent with previous reports; providing evidence that serum vitamin D deficiency could be an IR marker.

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

AIM

To 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.

METHODS

HEC 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.

RESULTS

Amongst 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.

CONCLUSION

The QUICKI index showed highest predictive accuracy in the normal birth weight and the low birth weight cohorts of Asian Indian males.

High triglycerides to HDL-cholesterol ratio is associated with insulin resistance in normal-weight healthy adults

AIM

To evaluate the association between high triglyceride/HDL-cholesterol (TG/HDL-C) ratio and insulin resistance (IR) or hyperinsulinemia after oral glucose tolerance test (OGTT) in normal-weight healthy adults.

METHODS

We carried out an analytical cross-sectional study in euthyroid non-diabetic adults, who attended the outpatient service of a private clinic in Lima-Peru from 2012 to 2016. Participants were divided in two groups according to the presence or absence of high TG/HDL-C ratio, IR or hyperinsulinemia after OGTT. TG/HDL-C ratio values ≥ 3 were considered as high. IR was defined as a Homeostasis Model Assessment (HOMA-IR) value ≥ 2.28 and hyperinsulinemia after OGTT as a serum insulin value ≥ 80μU/mL after 120 min of 75-g glucose intake. We elaborated crude and adjusted Poisson generalized linear models to evaluate the association between high TG/HDL-C ratio and IR or hyperinsulinemia after OGTT and reported the prevalence ratio (PR) with their respective 95% confidence intervals (95%CI).

RESULTS

We analyzed the data of 118 individuals. Prevalence of high TG/HDL-C ratio was 17.8% (n = 21) while the prevalence of IR and hyperinsulinemia after OGTT was 24.6% (n = 29) and 17.0% (n = 20), respectively. TG/HDL-C-ratio values were positively correlated with HOMA-IR (r = 0.498; p < 0.01) and serum insulin after OGTT (r = 0.326; p < 0.001). In the adjusted model, high TG/HDL-C ratio was associated with both IR (aPR = 3.16; 95%CI: 1.80-5.77) and hyperinsulinemia after OGTT (aPR = 2.36; 95%CI: 1.20-4.63).

CONCLUSIONS

High TG/HDL-C ratio was associated with both IR markers used in our study, appearing to be a clinically useful tool to assess IR in euthyroid normal-weight adults without type 2 diabetes mellitus.

Decreased serum microRNA-21 level is associated with obesity in healthy and type 2 diabetic subjects

BACKGROUND

Recently, much attention has been paid to the role of circulating microRNAs (miRNAs) as novel biomarkers for various diseases. The aim of this study was to investigate the level of a subset of miRNAs in serum samples of the diabetic and healthy subjects.

METHODS

Forty two healthy and 45 T2D subjects participated in this study. Serum miR-21, miR-126, and miR-146a levels were measured using real-time PCR.

RESULTS

There was no significant difference in the serum level of miR-21, miR-126, and miR-146a between the diabetic and non-diabetic groups. The level of miR-21 in obese non-diabetic and diabetic subjects was significantly lower than lean subjects. Correlation analyses in non-diabetic and diabetic groups revealed a significant negative correlation between the amount of miR-21 and body mass index, waist circumference, insulin, and HOMA-IR levels.

CONCLUSIONS

A reduced level of miR-21 might associate with obesity and its related metabolic traits such as hyperinsulinaemia.

Impact of cigarette smoking on the relationship between body mass index and insulin: Longitudinal observation from the Bogalusa Heart Study

OBJECTIVES

Despite the inverse association between cigarette smoking and body mass index (BMI), it is unknown whether the effect of smoking on insulin is mediated through decreased BMI. This study aims to examine the temporal relationship between BMI and insulin, the impact of smoking on this relationship and the mediation effect of BMI on the association between smoking and insulin levels.

METHODS

The longitudinal cohort consisted of 1121 adults (807 white and 314 black participants, mean age, 42.0 years at follow-up) for whom BMI and fasting insulin were measured twice, with an average follow-up period of 17.1 years. Cross-lagged panel and mediation analysis models were used to examine the temporal relationship between BMI and insulin, and the mediation effect of BMI on the smoking-insulin association.

RESULTS

Smoking was inversely associated with insulin (regression coefficient, -0.073; P = .015 at baseline and -0.121; P < .001 at follow-up), adjusting for age, race and gender. After additional adjustment for follow-up periods, the cross-lagged path coefficient from BMI to insulin (β, 0.226; P < .001) was significantly greater than that from insulin to BMI (β, -0.029; P = .208), with P < .001 for the difference. The path coefficient from BMI to insulin was significantly greater in non-smokers (β, 0.273; P < .001) than in smokers (β, 0.122; P = .046), with P = .013 for the difference. The mediation effect of BMI on the smoking-insulin association was estimated at 53.4% (P = .030) at baseline and 58.7% (P < .001) at follow-up.

CONCLUSIONS

These findings suggest that cigarette smoking has a significant impact on the one-directional relationship from BMI to insulin. The insulin-lowering effect of smoking is predominantly mediated through decreased BMI as the result of smoking.

Long-acting insulin analogs and cancer

AIMS

Hyperinsulinemia is a recognized risk factor for cancer and plays a major role for the increased cancer incidence in diabetic patients. Whether insulin analogs, and particularly long-acting analogs, worsen the pro-cancer effect of excess insulin is still controversial.

DATA SYNTHESIS

In this paper we summarize the biological bases for the potential detrimental effect of long-acting analogs on cancer cells and review the in vitro and in vivo evidence on this issue. Because of their different molecular structure relative to native insulin, insulin analogs may activate the insulin receptor (IR) and the post receptor pathways differently. Most, but not all, in vitro evidence indicate that long-acting analogs may have a stronger mitogenic potency than insulin on cancer cells. Notably insulin glargine, the most studied long-acting analog, also has a higher affinity for the insulin-like growth factor (IGF)-1 receptor, a potent growth mediator. In vitro observations, however, may not reflect what occurs in vivo when analogs are metabolized to derivatives with a different mitogenic activity. Clinical studies, mostly retrospective and predominantly concerning glargine, provide contrasting results. The only perspective trial found no cancer increase in patients treated with glargine. All these studies, however, have severe weaknesses because of the insufficient evaluation of important factors such as dose administered, length of exposure, patient follow-up duration and site-specific cancer investigation. Moreover, whether cancer promotion is a long-acting analog class characteristic or a specific effect of a single agent is not clear.

CONCLUSIONS

In conclusion the carcinogenic risk of long-acting analogs, and specifically glargine, can be neither confirmed nor excluded. A personalized and shared decision, considering all the individual risk factors (metabolic and non-metabolic), is the suggestion for the clinician.

High dietary intake of branched-chain amino acids is associated with an increased risk of insulin resistance in adults

BACKGROUND

The aim of this study was to investigate the association between branched-chain amino acid (BCAA) intake and markers of insulin metabolism in adults.

METHODS

This cohort study was conducted within the framework of the Tehran Lipid and Glucose Study on 1205 subjects, aged ≥20 years, who were followed-up for a mean of 2.3 years. Dietary intake of BCAAs, including valine, leucine, and isoleucine, was determined using a valid and reliable food frequency questionnaire. Hyperinsulinemia, β-cell dysfunction, insulin resistance (IR), and insulin insensitivity were determined according to optimal cut-off values. Logistic regression was to estimate the occurrence of IR across tertiles of BCAA intake.

RESULTS

The mean (± SD) age and BCAA intake of participants (43% male) at baseline were 42.7 ± 13.1 years and 13.8 ± 5.1 g/day, respectively. The incidence of hyperinsulinemia, β-cell dysfunction, insulin insensitivity, and IR was 19.5%, 24.0%, 28.0%, and 12.5%, respectively. After adjustment for confounding variables, subjects in the highest tertile for total BCAAs (odds ratio [OR] 1.67; 95% confidence interval [CI] 1.03-2.71), leucine (OR 1.75; 95% CI 1.09-2.82), and valine (OR 1.61; 95% CI 1.01-2.60) intake had a greater risk of incident IR than subjects in the lowest tertile. A higher intake of isoleucine was not associated with risk of incident IR. There was no association of total BCAAs, leucine, isoleucine, and valine intake with the risk of hyperinsulinemia, insulin insensitivity, or β-cell dysfunction.

CONCLUSION

The findings of this study support the hypothesis that higher intakes of BCAAs may have adverse effects on the development of IR.

Errors in insulin treatment management and risk of lipohypertrophy

AIMS

Lipohypertrophy (LH) represents the most common skin-related complication associated with insulin therapy. Our aim is to estimate the prevalence of LH among insulin-treated patients, to identify its association with errors in insulin injection technique and storage, and the correlation between LH, risk of hypoglycemia, and glycemic control.

METHODS

Consecutive patients with T1DM or T2DM, attending a diabetes clinic for a routine visit, were administered an anonymous questionnaire investigating the modalities of insulin injection, the correct use of pen device, insulin storage, and reported frequency of hypoglycemic episodes. The presence of LH was assessed by inspection and palpation of injection sites.

RESULTS

Overall, 352 patients were enrolled (mean age 68 ± 12 years, 43.2% males, 88.9% with T2DM, mean duration of insulin therapy 9.1 ± 8.6 years). The prevalence of LH was 42.9%. At multivariate analysis, the strongest correlates of LH were not spacing injections (OR 20.4; 95% CI 10.5-39.6) and not rotating the site of injection (OR 2.01; 95% CI 1.08-3.75). Increasing doses of insulin and longer duration of insulin therapy also increased the risk of LH. The presence of LH was associated with a 2.7 times higher risk of severe hypoglycemia. Higher daily insulin doses, lack of rotation of injection sites, and keeping insulin in use in the refrigerator were independent correlates of higher HbA1c levels.

CONCLUSIONS

Insulin injection technique is suboptimal in many patients, highlighting the need for improved patient education. Increasing the awareness of the importance of preventing lipohypertrophy and insulin injection errors represents an important tool to reduce the clinical, social, and economic burden of diabetes.

Hyperinsulinemia and elevated systolic blood pressure independently predict white matter hyperintensities with associated cognitive decrement in the middle-aged offspring of dementia patients

Cerebrovascular disease is an independent risk factor for dementia that may also be synergistic with Alzheimer's disease. In recent years attention has switched from cerebral infarcts to microvascular disease as the primary cause of cerebrovascular cognitive decline, with damage to the white matter the primary mechanism. Uncertainties remain regarding the risks posed by different types vascular threat, the extent to which cerebrovascular damage occurs in middle age, and whether relatively "normal" amounts of white matter damage are accompanied by meaningful degrees of cognitive decline. We explored these issues via laboratory, cardiovascular, cognitive, and magnetic resonance imaging (MRI) data in 67 middle-aged cognitively normal offspring of dementia patients. The sample was enriched for vascular risk. Plasma insulin, 24-h systolic blood pressure, body mass index, age, and % small dense LDL cholesterol were the strongest correlates of MRI white matter hyperintensity (WMH) volume. With shared variance controlled for, 24 h systolic BP, plasma insulin, and age remained as significant predictors of WMH volume. An interaction variable (24 h BP * insulin) did not improve the prediction of WMH. WMH volume correlated negatively with cognition. No evidence for an ApoE ε4 effect emerged for either WMH or cognition. Hypertension and hyperinsulinemia appear to pose independent, consequential threats to the cerebral small vessel vasculature in middle age, reflected in the presence of areas of WMH on MRI scans. Our data show that even modest WMH volumes in middle age are associated with cognitive decrement, underscoring the importance of aggressive treatment and lifestyle modifications to address vascular risk throughout adulthood.

The role of hyperinsulinemia as a cardiometabolic risk factor independent of obesity in polycystic ovary syndrome

The aim of this study was to utilize various insulin resistance measuring methods to determine whether insulin resistance and other parameters impact the serum lipid levels of polycystic ovary syndrome (PCOS) patients and how the serum lipid levels in these patients are affected by the body mass index (BMI). Our dataset included patients between the ages of 16 and 42 (N = 228) from the outpatient endocrinology clinic of the Department of Obstetrics and Gynecology, who demonstrated increased hair growth and bleeding disorders and came for a routine oral glucose tolerance test (OGTT). Differences in the serum lipid levels were evaluated by t-test and linear regression analysis after adjusting for BMI. A stepwise regression model was constructed to evaluate the influence of each variable on the lipid levels. In PCOS patients, we found that dyslipidemia is more prevalent among hyperinsulinemic women compared with normoinsulinemic women, even after normalizing for BMI. PCOS patients with insulin resistance, determined by the insulin sensitivity index (ISI) method, showed more significant lipid abnormalities such as low high-density lipoprotein (HDL) and apo-A levels and high total cholesterol, low-density lipoprotein (LDL) and apo-B levels than if insulin resistance (IR) determination was based on insulin level or homeostatic model assessment (HOMA).

Overweight and obesity in children and adolescents with Down syndrome-prevalence, determinants, consequences, and interventions: A literature review

BACKGROUND

Children with Down syndrome (DS) are more likely to be overweight or obese than the general population of youth without DS.

AIMS

To review the prevalence of overweight and obesity and their determinants in youth with DS. The health consequences and the effectiveness of interventions were also examined.

METHODS AND PROCEDURES

A search using MEDLINE, Embase, Web of Science, Scopus, CINAHL, PsycINFO, SPORTDiscus, LILACS, and COCHRANE was conducted. From a total of 4280 studies, we included 45 original research articles published between 1988 and 2015.

OUTCOMES AND RESULTS

The combined prevalence of overweight and obesity varied between studies from 23% to 70%. Youth with DS had higher rates of overweight and obesity than youths without DS. Likely determinants of obesity included increased leptin, decreased resting energy expenditure, comorbidities, unfavorable diet, and low physical activity levels. Obesity was positively associated with obstructive sleep apnea, dyslipidemia, hyperinsulinemia, and gait disorder. Interventions for obesity prevention and control were primarily based on exercise-based programs, and were insufficient to achieve weight or fat loss.

CONCLUSIONS AND IMPLICATIONS

Population-based research is needed to identify risk factors and support multi-factorial strategies for reducing overweight and obesity in children and adolescents with DS.

Identifying hyperinsulinaemia in the absence of impaired glucose tolerance: An examination of the Kraft database

OBJECTIVE

Hyperinsulinaemia is associated with development of chronic metabolic disease and is emerging as a health risk independent to that of insulin resistance. However, little is known to what extent hyperinsulinaemia occurs with normal glucose tolerance in lean subjects.

METHOD

Oral glucose tolerance tests with concurrent insulin assay were conducted during the 1970s-1990s. Participants were classified according to glucose tolerance and insulin response pattern. Analysis of variance compared differences in plasma glucose, plasma insulin, and demographic and metabolic risk factors between groups.

RESULTS

Participants with normal glucose tolerance comprised 54% (n=4185) of the total cohort. Of these, just over half (n=2079) showed hyperinsulinaemia despite normal glucose clearance. Obesity had a modest association with hyperinsulinaemia in people with normal glucose tolerance. Fasting insulin had limited value in diagnosing hyperinsulinaemia. The majority of participants (93%) with impaired glucose tolerance or diabetes had concurrent hyperinsulinaemia.

CONCLUSION

Hyperinsulinaemia in the absence of impaired glucose tolerance may provide the earliest detection for metabolic disease risk and likely occurs in a substantial proportion of an otherwise healthy population. Dynamic insulin patterning may produce more meaningful and potentially helpful diagnoses. Further research is needed to investigate clinically useful hyperinsulinaemia screening tools.

A Nested Case-Control Study of Metabolically Defined Body Size Phenotypes and Risk of Colorectal Cancer in the European Prospective Investigation into Cancer and Nutrition (EPIC)

BACKGROUND

Obesity is positively associated with colorectal cancer. Recently, body size subtypes categorised by the prevalence of hyperinsulinaemia have been defined, and metabolically healthy overweight/obese individuals (without hyperinsulinaemia) have been suggested to be at lower risk of cardiovascular disease than their metabolically unhealthy (hyperinsulinaemic) overweight/obese counterparts. Whether similarly variable relationships exist for metabolically defined body size phenotypes and colorectal cancer risk is unknown.

METHODS AND FINDINGS

The association of metabolically defined body size phenotypes with colorectal cancer was investigated in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Metabolic health/body size phenotypes were defined according to hyperinsulinaemia status using serum concentrations of C-peptide, a marker of insulin secretion. A total of 737 incident colorectal cancer cases and 737 matched controls were divided into tertiles based on the distribution of C-peptide concentration amongst the control population, and participants were classified as metabolically healthy if below the first tertile of C-peptide and metabolically unhealthy if above the first tertile. These metabolic health definitions were then combined with body mass index (BMI) measurements to create four metabolic health/body size phenotype categories: (1) metabolically healthy/normal weight (BMI < 25 kg/m2), (2) metabolically healthy/overweight (BMI ≥ 25 kg/m2), (3) metabolically unhealthy/normal weight (BMI < 25 kg/m2), and (4) metabolically unhealthy/overweight (BMI ≥ 25 kg/m2). Additionally, in separate models, waist circumference measurements (using the International Diabetes Federation cut-points [≥80 cm for women and ≥94 cm for men]) were used (instead of BMI) to create the four metabolic health/body size phenotype categories. Statistical tests used in the analysis were all two-sided, and a p-value of <0.05 was considered statistically significant. In multivariable-adjusted conditional logistic regression models with BMI used to define adiposity, compared with metabolically healthy/normal weight individuals, we observed a higher colorectal cancer risk among metabolically unhealthy/normal weight (odds ratio [OR] = 1.59, 95% CI 1.10-2.28) and metabolically unhealthy/overweight (OR = 1.40, 95% CI 1.01-1.94) participants, but not among metabolically healthy/overweight individuals (OR = 0.96, 95% CI 0.65-1.42). Among the overweight individuals, lower colorectal cancer risk was observed for metabolically healthy/overweight individuals compared with metabolically unhealthy/overweight individuals (OR = 0.69, 95% CI 0.49-0.96). These associations were generally consistent when waist circumference was used as the measure of adiposity. To our knowledge, there is no universally accepted clinical definition for using C-peptide level as an indication of hyperinsulinaemia. Therefore, a possible limitation of our analysis was that the classification of individuals as being hyperinsulinaemic-based on their C-peptide level-was arbitrary. However, when we used quartiles or the median of C-peptide, instead of tertiles, as the cut-point of hyperinsulinaemia, a similar pattern of associations was observed.

CONCLUSIONS

These results support the idea that individuals with the metabolically healthy/overweight phenotype (with normal insulin levels) are at lower colorectal cancer risk than those with hyperinsulinaemia. The combination of anthropometric measures with metabolic parameters, such as C-peptide, may be useful for defining strata of the population at greater risk of colorectal cancer.

Safety, efficacy and glucose turnover of reduced prandial boluses during closed-loop therapy in adolescents with type 1 diabetes: a randomized clinical trial

AIMS

To evaluate safety, efficacy and glucose turnover during closed-loop with meal announcement using reduced prandial insulin boluses in adolescents with type 1 diabetes (T1D).

METHODS

We conducted a randomized crossover study comparing closed-loop therapy with standard prandial insulin boluses versus closed-loop therapy with prandial boluses reduced by 25%. Eight adolescents with T1D [3 males; mean (standard deviation) age 15.9 (1.5) years, glycated haemoglobin 74 (17) mmol/mol; median (interquartile range) total daily dose 0.9 (0.7, 1.1) IU/kg/day] were studied on two 36-h-long visits. In random order, subjects received closed-loop therapy with either standard or reduced insulin boluses administered with main meals (50-80 g carbohydrates) but not with snacks (15-30 g carbohydrates). Stable-label tracer dilution methodology measured total glucose appearance (Ra_total) and glucose disposal (Rd).

RESULTS

The median (interquartile range) time spent in target (3.9-10 mmol/l) was similar between the two interventions [74 (66, 84)% vs 80 (65, 96)%; p = 0.87] as was time spent above 10 mmol/l [21.8 (16.3, 33.5)% vs 18.0 (4.1, 34.2)%; p = 0.87] and below 3.9 mmol/l [0 (0, 1.5)% vs 0 (0, 1.8)%; p = 0.88]. Mean plasma glucose was identical during the two interventions [8.4 (0.9) mmol/l; p = 0.98]. Hypoglycaemia occurred once 1.5 h post-meal during closed-loop therapy with standard bolus. Overall insulin delivery was lower with reduced prandial boluses [61.9 (55.2, 75.0) vs 72.5 (63.6, 80.3) IU; p = 0.01] and resulted in lower mean plasma insulin concentration [186 (171, 260) vs 252 (198, 336) pmol/l; p = 0.002]. Lower plasma insulin was also documented overnight [160 (136, 192) vs 191 (133, 252) pmol/l; p = 0.01, pooled nights]. Ra_total was similar [26.3 (21.9, 28.0) vs 25.4 (21.0, 29.2) µmol/kg/min; p = 0.19] during the two interventions as was Rd [25.8 (21.0, 26.9) vs 25.2 (21.2, 28.8) µmol/kg/min; p = 0.46].

CONCLUSIONS

A 25% reduction in prandial boluses during closed-loop therapy maintains similar glucose control in adolescents with T1D whilst lowering overall plasma insulin levels. It remains unclear whether closed-loop therapy with a 25% reduction in prandial boluses would prevent postprandial hypoglycaemia.

Hyperinsulinemia, insulin resistance and colorectal adenomas: A meta-analysis

BACKGROUND

Insulin stimulates cell proliferation and inhibits apoptosis. While epidemiologic studies have investigated associations between markers of insulin resistance/hyperinsulinemia (i.e., circulating insulin, homeostasis model assessment-insulin resistance (HOMA-IR), C-peptide) and risk of colorectal adenoma (CRA), the effect size has not yet been quantified.

OBJECTIVE

We aimed to summarize the association between hyperinsulinemia/insulin resistance and risk of CRA, including whether the association is independent of adiposity.

MATERIALS AND METHODS

Pubmed and Embase were searched through April, 2015 to identify observational studies investigating the associations between insulin, C-peptide and HOMA-IR and CRA risk. Using the highest versus lowest category meta-analysis and dose-response meta-analysis based on a random-effects model, we estimated summary odds ratio (OR) and the corresponding 95% confidence interval (95% CI).

RESULTS

A total of 27 studies (insulin: 16 studies including 14,007 cases; C-peptide: 11 studies including 8639 cases; HOMA-IR: 8 studies including 11,619 cases) were included in this meta-analysis. The summary ORs of CRA comparing the highest with the lowest quantile were 1.33 for insulin (95% CI=1.12-1.58, I(2)=73.9%, Pheterogeneity<0.001), 1.44 for C-peptide (95% CI=1.13-1.83, I(2)=63.5%, Pheterogeneity=0.003), and 1.33 for HOMA-IR (95% CI=1.10-1.60, I(2)=69.1%, Pheterogeneity=0.004). Upon stratification by ethnicity, higher levels of insulin and C-peptide were significantly associated with increased risk of CRA in non-Asian ethnicity (summary OR for insulin=1.67 [95% CI=1.28-2.17], I(2)=34.9%, Pheterogeneity=0.16; summary OR for C-peptide=1.59 [95% CI=1.22-2.08], I(2)=21.5%, Pheterogeneity=0.27) but not in Asians (summary OR for insulin=1.10 [95% CI=0.92-1.33], I(2)=76.6%, Pheterogeneity=0.001; summary OR for C-peptide=1.27 [95% CI=0.84-1.91], I(2)=72.6, Pheterogeneity=0.01). We observed evidence for the existence of publication bias for insulin (P=0.01 by Egger test) and HOMA-IR (P=0.05 by Egger test). The results were confirmed in linear dose-response meta-analysis. These significant positive associations generally persisted even after adjustment for adiposity, although the effect size was substantially attenuated.

CONCLUSIONS

Independent of adiposity, higher levels of insulin, C-peptide, and HOMA-IR were significantly associated with increased risk of CRA. The weaker associations and high heterogeneity in Asian studies warrant further research. These results indicate that insulin resistance and hyperinsulinemia may contribute in part to the association between obesity and CRA risk.

Hyperinsulinemia in newly diagnosed patients with multiple sclerosis

There are limited data regarding glucose metabolism dysregulation in multiple sclerosis (MS). Present study investigates glucose and insulin response during oral glucose tolerance test (oGTT) in MS patients. We examined 19 MS patients and 19 age, sex and body mass index (BMI) matched healthy controls. MS patients were newly diagnosed, untreated and with low Expanded Disability Status Scale (EDSS) score (1.1 ± 0.7). Plasma glucose, lactate, insulin and GLP-1 during oGTT, and fasting adipokines, lipid and inflammatory parameters were analyzed. Insulin sensitivity indices (ISI) were calculated. MS patients had comparable fasting (5.2 ± 0.3 vs. 5.0 ± 0.4 mmol/l, p = 0.05) and post-load glucose concentrations as controls. Insulin response to oral glucose load in MS was increased (p = 0.022). Insulin sensitivity was lower in MS compared to controls [ISI(Matsuda) 6.95 ± 3.44 vs. 10.60 ± 4.81, p = 0.011 and ISI(Cederholm) 49.9 ± 15.3 vs. 61.3 ± 16.3, p = 0.032]. We did not find any difference in lactate, GLP-1, total, HDL and LDL cholesterol, triglycerides, interleukin 6, tumor necrosis factor, C-reactive protein, resistin, leptin, adiponectin levels between groups. We found decreased insulin sensitivity with postprandial hyperinsulinemia in MS patients, which seems not to be related to chronic inflammation or physical inactivity. The role of hyperinsulinemia in CNS function impairment should be further investigated.

Should insulin resistance be screened in lean hirsute women?

The role of insulin resistance (IR) is well-documented in obese women with polycystic ovary syndrome (PCOS). Controversies exist concerning the presence of IR in idiopathic hirsutism (IH) or if it is a manifestation of high body mass index (BMI). We aimed to investigate the presence/absence of IR in lean hirsute women. One-hundred fifty-one lean women with hirsutism [96 PCOS (group 1) and 55 IH (group 2)] and 58 age-and BMI-matched healthy controls (group 3) were recruited in the study (mean age 25.21 ± 6.1 versus 26.26 ± 4.6years; BMI 21.79 ± 1.7 versus 22.02 ± 2.2 kg/m(2), respectively). Significantly higher insulin and HOMA-IR, and significantly lower fasting glucose insulin ratio (FGIR), quantitative insulin sensitivity check index (QUICKI), reciprocal insulin, and Raynaud index were detected in groups 1 and 2 than in group 3 (p < 0.05). These IR indices were similar between groups 1 and 2. The number of patients with IR (HOMA-IR > 2, FGIR < 7.2, or QUICKI < 0.357) was significantly higher in groups 1 and 2 than in group 3, but was similar between groups 1 and 2. A higher frequency of IR occurs in lean hirsute women regardless of they having PCOS or IH. IR may contribute to aetiopathogenesis of IH, or may cause some metabolic abnormalities in these patients.

Relationship of hyperinsulinaemia, insulin resistance and β-cell dysfunction with incident diabetes and pre-diabetes: the Tehran Lipid and Glucose Study

AIMS

To examine the association of fasting insulin, insulin resistance and reduced β-cell function with incident Type 2 diabetes and pre-diabetes (isolated impaired fasting glucose/isolated impaired glucose tolerance and combined impaired fasting glucose/impaired glucose tolerance).

METHODS

An Iranian population comprising 1532 men and 2221 women, aged ≥ 20 years, with normal fasting glucose and normal glucose tolerance at baseline, were enrolled in the study. Multivariable Cox proportional hazard models were used to calculate the hazard ratios and 95% CIs of fasting insulin, updated homeostasis model assessments of insulin resistance and β-cell function for incident Type 2 diabetes, isolated impaired fasting glucose, isolated impaired glucose tolerance and combined impaired fasting glucose/impaired glucose tolerance.

RESULTS

During a median follow-up of 9.2 years, the annual incidence rates (95% CI) of diabetes were 3.73 (2.74-4.94) and 4.06 (3.21-5.06) per 1000 person-years in men and women, respectively. In both men and women, fasting insulin and homeostasis model assessment of insulin resistance (≥ 75th percentile) were significantly associated with incident diabetes and combined impaired fasting glucose/impaired glucose tolerance; however, reduced β-cell function as measured by homeostasis model assessment of β-cell function (< 25th percentile) was associated with incident isolated impaired fasting glucose solely in men [hazard ratio 1.35 (95% CI 1.02-1.78)] in multivariable analysis including waist-hip ratio). Hyperinsulinaemia, insulin resistance and β-cell dysfunction were not related to the incidence of isolated impaired glucose tolerance in either gender.

CONCLUSIONS

Fasting hyperinsulinaemia and insulin resistance were strong risk factors for progression to diabetes and combined impaired fasting glucose/impaired glucose tolerance in a population with normal fasting glucose/normal glucose tolerance. In addition, impaired β-cell function at baseline was related to the development of isolated impaired fasting glucose only in men and, in both men and women, neither insulin resistance nor β-cell dysfunction were associated with incident isolated impaired glucose tolerance.

25-Hydroxyvitamin D levels are related to hyperinsulinemia in polycystic ovary syndrome

AIM

To determine 25-hydroxyvitamin D levels and the relationship between 25-hydroxyvitamin D and metabolic disturbances including insulin resistance in women with PCOS.

MATERIALS AND METHODS

We compared biochemical, hormonal parameters and 25-hydroxyvitamin D levels of 58 women with PCOS and 38 body mass index matched controls.

RESULTS

There was no difference in 25-hydroxyvitamin D levels of women with PCOS and the control group. Low 25-hydroxyvitamin D levels in women with PCOS were related to higher insulin levels (r = -0.271 and p = 0.042). More than 90% of the subjects had hypovitaminosis D. The negative relationship between 25-hydroxyvitamin D levels and body mass index did not reach statistical significance.

CONCLUSION

Low 25-hydroxyvitamin D levels were related to hyperinsulinemia in women with PCOS.

Diagnosis of hyperinsulinaemia in a normoglycaemic healthy Indian Population--developing ethnic reference ranges

CONTEXT

Reference limits for diagnosing hyperinsulinaemia are currently derived from non-Indian cohorts and have not been validated in Indians even though it is acknowledged that different patterns of insulin secretion are seen across ethnicities.

AIMS

To develop ethnicity specific reference limits for insulin levels in a normoglycaemic healthy Indian cohort in order to derive a clinical cut off for hyperinsulinaemia as an effective screening tool for predicting future risk of metabolic and cardiovascular disease.

SETTINGS AND DESIGN

Prospective analysis of plasma insulin levels in healthy normoglycaemic volunteers availing diagnostic facilities at a central reference laboratory in Mumbai.

METHODS AND MATERIAL

122 normoglycaemic males between 19-73 years and 126 females between 19-55 years of age were selected based on a screening questionnaire as per the Clinical Laboratory and Standards Institute (CLSI) guidance document for deriving reference ranges. Fasting insulin levels were analysed using a Chemiluminescent Microparticle Immunoassay platform and derived results were analysed to determine reference limits for insulin.

STATISTICAL ANALYSIS USED

A non-parametric method of statistical analysis was used to determine the 2.5 and 97.5% limits with 90% confidence intervals.

RESULTS

Reference range for insulin in a normoglycemic Indian cohort was derived as 2.7-17 uIU/ml which established 17 uIU/ml as the clinical cut off for diagnosing hyperinsulinemia in healthy Indians.

CONCLUSIONS

Reference limits for insulin in normoglycemic Indians needs to be revised to 2.7-17 uIU/ ml. Clinical cut off for hyperinsulinemia needs to be lowered to 17 uIU/ml from currently used cut offs which range from 25-31 ulU/ml.

KEY MESSAGES

Reference limits currently used for diagnosing hyperinsulinemia in healthy normoglycemic adults need to be revised and made specific for different ethnicities. In Indians the upper limit of the normal reference range for insulin levels needs to be brought down to 17 uIU/ml from the existing 25-31 u IU/ml. This modified cut off would help clinicians identify apparently healthy individuals who may need to be screened for a future risk of metabolic and cardiovascular disorders.

Post-absorptive glucose lowering in normal healthy individuals: an epidemiological observation

Post-absorptive glucose lowering (PALG) is observed in individuals with glucose intolerance and in healthy individuals. We report a prevalence of about 23% among healthy Asian Indians. Individuals with PALG are characterized by leaner phenotype, low body fat percentage, increased insulin sensitivity and higher fasting glucose levels.

The long-term impact of intrauterine growth restriction in a diverse U.S. cohort of children: the EPOCH study

OBJECTIVE

To explore the long-term impact of intrauterine growth restriction (IUGR) among a diverse, contemporary cohort of U.S. children.

DESIGN AND METHODS

A retrospective cohort of 42 children exposed to IUGR and 464 unexposed who were members of Kaiser Permanente of Colorado. Height and weight measurements since birth and measures of abdominal adiposity and insulin-resistance were measured at an average age of 10.6 (±1.3) years.

RESULTS

Infants born IUGR experienced "catch-up growth" in the first 12 months of life at a rate of 3.58 kg/m² compared to 2.36 kg/m² in unexposed infants (P = 0.01). However, after 1 year of age, no differences in BMI growth velocity were observed. Nevertheless children exposed to IUGR had higher waist circumference (67.0 vs. 65.3 cm, P = 0.03), higher insulin (15.2 vs. 11.0 μU/ml, P = 0.0002), higher HOMA-IR (2.8 vs. 2.3, P = 0.03), and lower adiponectin levels (9.0 vs. 12.0 μg/ml, P = 0.003) in adolescence, independent of other childhood and maternal factors.

CONCLUSIONS

Our data from a contemporary US cohort suggests that children exposed to IUGR have increased abdominal fat and increased insulin resistance biomarkers despite no differences in BMI growth patterns beyond 12 months of age. These data provide further support for the fetal programming hypothesis.

Illicit drug use and cardiometabolic disease risk: an analysis of 2005-2008 National Health and Nutrition Examination Survey data

PURPOSE

To explore the association between illicit drug use (IDU) and cardiometabolic disease risk factors (CDRF) in a nationally representative sample of adults.

METHODS

The 2005-2008 National Health and Nutrition Examination Surveys data from 20- to 45-year-old adults (n = 8738) were utilised to analyze the relationship between IDU (ever used, repeated use and current use) and CDRF (hyperlipidemia, hyperinsulinemia, hypertension, elevated C-reactive protein, body mass index, waist circumference and cigarette use) via chi square and logistic regression analyses. Age, gender, race/ethnicity, education level, poverty to income ratio (PIR), and alcohol use were included as confounders in the models.

RESULTS

Individuals who reported drug use (DU) at least once in lifetime were more likely to have CDRF than non-DU (NDU) (OR = 1.3, p = 0.004). Females with DU, IDU at least once in lifetime, and with repeated IDU were about 1.5 times more likely than their NDU counterparts to have CDRF (p < 0.0001, p = 0.02, p = 0.02, respectively).

CONCLUSION

Results from this study suggest that healthcare professionals should be aware that patients with a history of DU may be at heightened risk for cardiometabolic disease. Females in particular have a heightened cluster of CDRF across drug-use categories.

Plasma follistatin is elevated in patients with type 2 diabetes: relationship to hyperglycemia, hyperinsulinemia, and systemic low-grade inflammation

BACKGROUND

Plasma follistatin is elevated in patients with low-grade inflammation and insulin resistance as observed with polycystic ovary syndrome. In the present study, we evaluated plasma follistatin in patients with type 2 diabetes characterised by low-grade inflammation and assessed the acute effects of hyperglycemia, hyperinsulinemia and LPS on plasma follistatin.

METHODS

Baseline plasma follistatin and inflammatory biomarkers were measured in a cross-sectional study that involved 95 patients with type 2 diabetes and 103 matched controls. To determine the acute effect of hyperglycemia and hyperinsulinemia on follistatin, hyperglycemic and hyperinsulinemic-euglycemic clamps were performed in five healthy males. Furthermore, 15 patients with type 2 diabetes and 22 healthy controls were challenged with low-dose LPS to determine the effect on follistatin.

RESULTS

Patients with type 2 diabetes have higher HOMA2-IR values mean [95% CI] 1.64 [1.40-1.93] versus mean 0.86 [0.75-0.99], p < 0.001 and inflammatory markers compared with controls. Baseline plasma follistatin is elevated in patients with type 2 diabetes compared with controls mean 1564 [1456-1680] versus mean 1328 [1225-1440] ng/L, p = 0.003 and correlates with fasting glucose levels (r = 0.44, p < 0.0001), 2 h glucose (r = 0.48, p < 0.0001), HbA1c (r = 0.41, p < 0.0001), triacylglycerol (r = 0.28, p = 0.008) and total cholesterol (r = 0.33, p = 0.004) in patients but not in controls. No correlation exists between plasma follistatin and inflammatory biomarkers in either of the groups. Neither hyperglycemia, hyperinsulinemia nor LPS increase plasma follistatin.

CONCLUSIONS

Plasma follistatin is moderately elevated in patients with type 2 diabetes. Our findings suggest that this is not likely caused by hyperglycemia, hyperinsulinemia or systemic low-grade inflammation.