Higher Homeostatic Model Assessment-insulin Resistance Research Articles

A Cross-sectional Study to Assess Insulin Resistance and Atherogenic Index of Plasma as Predictors of Risk of Cardiometabolic Disease among Undergraduate Medical Students at a Tertiary Care Teaching Hospital, Karnataka

Background: Medical profession is known for stress and challenges due to hectic academic schedules which makes students, high-risk candidates for diabetes mellitus, hypertension and cardiometabolic disease (CMD). Surrogate markers such as homeostatic model assessment insulin resistance (HOMA-IR) and atherogenic index of plasma (AIP) along with routine parameters enable early prediction of the disease. Hence, this study aimed at determining HOMA-IR and AIP along with assessment of their correlation with anthropometric and biochemical parameters associated with CMD risk among undergraduate medical students. Methodology : 460 medical students consented to participate in the study. The data related to socio-demographic profile, anthropometry, blood pressure and biochemical parameters such as fasting plasma glucose (FPG), fasting plasma insulin (FPI) and lipid profile was collected and analyzed. HOMA-IR and AIP were calculated. The strength of association between study variables was determined by relevant statistics. Results: The study showed the prevalence of overweight (17.8%), obesity (20.4%), pre-hypertension (37.82%) and hypertension (3.47%). 98.5% of the participants had normal FPG and FPI, whereas 1.5% had impaired levels. Lipid profile analysis showed hypercholesterolemia (3.7%), hypertriglyceridemia (8.1%), increased LDL-c (33.7%) and reduced HDL-c (55.2%). High HOMA-IR and AIP were contributed by 28.9% and 73.3% respectively. HOMA-IR and AIP showed statistically significant positive correlation with CMD risk factors. Conclusion: HOMA-IR and AIP considered as the better predictors of CMD risk among apparently healthy medical students. Thus, incorporation of these surrogate markers along with routine parameters for regular screening can help in early prediction of the risk of CMD among undergraduate medical students. Keywords: Homeostatic model assessment insulin resistance, Atherogenic index of plasma, Cardiometabolic disease, Medical students

The alterations of circulating mucosal-associated invariant T cells in polycystic ovary syndrome.

Polycystic ovary syndrome (PCOS) is the most common endocrine disorder affecting reproductive age females and an important cause of infertility. Although the etiology is complex and its pathogenesis remains unclear, the pathological process of PCOS is tightly related with the immune dysfunction and gut microbial dysbiosis. Mucosal-associated invariant T (MAIT) cells are a subset of innate-like T cells which can regulate inflammation through the production of cytokines and play a role in regulating the gut microbiota. We aim to evaluate the correlation between characteristics of PCOS and MAIT cells as well as their impact on cytokine secretion. Peripheral blood samples were taken from PCOS patients (n=33) and healthy controls (n=30) during 2-5 days of the menstrual period. The frequencies of MAIT cells and T cells were measured by flow cytometry. Cytokines interleukin 17 (IL-17), interleukin 22(IL-22), interferon γ (IFN-γ) and granzyme B were determined by Enzyme-linked immunosorbent assay (ELISA). The frequency of MAIT cells was significantly reduced in the blood of PCOS patients compared with the controls, and negatively correlated with Body Mass Index (BMI), Homeostatic model assessment- insulin resistance (HOMA-IR) index, and Anti Miillerian Hormone (AMH). Thus, the frequencies of MAIT cells decreased in PCOS patients with abnormal weight (BMI≥24kg/m2), higher HOMA-IR (≥1.5), and excessive AMH (≥8ng/ml). The Cytokine IL-17 was significantly higher in PCOS patients and negatively correlated with the frequency of MAIT cells. Even though the IL-22 was lower in PCOS Patients, no correlation with MAIT cells was detected. In subgroup, CD4+MAIT cells correlated with BMI, AMH, and testosterone (T) levels. The frequency change of MAIT cells may play a significant role in the pathogenesis of PCOS. Exploring these interactions with MAIT cells may provide a new target for PCOS treatment and prevention.

Western-style diet does not negatively affect the healthy aging benefits of lifelong restrictive feeding

BACKGROUND: Lifelong consumption of a Western-style diet is a risk factor for developing metabolic disorders and therefore impairs healthy aging. Dietary restriction (DR) could delay the onset of age-related diseases and prolong life span, however, the extent to which this depends on diet type is poorly understood. OBJECTIVE: To study whether feeding a Western-style diet affects the healthy aging benefits of DR. METHODS: Mice fed a Western-style diet (ad libitum and DR) were compared to those fed a standard healthy diet (ad libitum and DR). Survival and several metabolic and endocrine parameters were analyzed. RESULTS: Lifelong consumption of a Western-style diet resulted in increased adiposity, elevated triglyceride levels in plasma, higher homeostatic model assessment-insulin resistance and higher resting metabolic rate in mice compared to the standard diet group. This was accompanied by reduced survival in the Western-style diet group. DR irrespective of diet type improved abovementioned parameters. CONCLUSIONS: Lifelong restricted consumption of Western-style diet led to improved metabolic and endocrine parameters, and increased survival compared to the ad libitum Western-style diet group. Interestingly, the survival was comparable in restricted Western-style and standard diet groups, suggesting that reduced food intake rather than diet composition play more important role in promoting longevity/survival.

Association Between Fat Mass or Fat Fibrotic Gene Expression and Polyneuropathy in Subjects With Obesity: A Korean Metabolic Bariatric Surgery Cohort.

AimWe aimed to investigate the association between obesity-related parameters and polyneuropathy (PN) and to evaluate inflammatory and fibrotic gene expression of fat as a potential mediator in subjects scheduled to undergo metabolic bariatric surgery (MBS).MethodsThis was a cross-sectional study of MBS cohort. Body composition and visceral fat area (VFA) were quantified by bioimpedance analysis and computed tomography scan. PN was defined by Michigan Neuropathy Screening Instrument–Physical Examination score was > 2. We measured mRNA expression level of FN1, TIMP1, CCL2, and CXCL8 in omental fat tissue.ResultsOf 189 subjects (mean age, 39.4 years; 69 [36.5%] male; mean body mass index, 38.5 kg/m2), prevalence of PN was 9.1% in subjects without diabetes (n = 110) and 20.3% in those with diabetes (n = 79). Nondiabetic subjects with PN had higher homeostatic model assessment-insulin resistance (6.8 ± 3.5 vs 4.5 ± 2.8, p = 0.041), and increased fat mass (58.5 ± 12.5 kg vs 50.5 ± 10.7 kg, p = 0.034), and VFA (309.4 ± 117.6 cm2 vs 243.5 ± 94.2 cm2, p = 0.046) compared to those without PN. These obesity-related parameters were significantly associated with the presence of PN after adjusting for conventional risk factors of PN only in subjects without diabetes. In contrast, a fibrotic gene such as TIMP1 was independently associated with PN (adjusted odds ratio of 1.56; 95% confidence interval 1.06, 2.30) only in subjects with diabetes.ConclusionIncreased adiposity was independently associated with PN in obese subjects without diabetes. In contrast, this association was not significant after adjusting conventional risk factors of PN in obese subjects with diabetes but increased fibrotic gene expression in fat was associated with PN in this group.

Interrelationship of Gut Microbiota, Obesity, Body Composition and Insulin Resistance in Asians with Type 2 Diabetes Mellitus.

Metabolic syndrome (MS) has been an important health issue in the world, and insulin resistance (IR) is one of the characteristics of MS, increasing the risk for the onset and poor prognosis of type 2 diabetes mellitus (T2D). However, the interactional effect of obesity or abnormal body composition on the correlation between gut microbiota and IR in T2D patients is not well-explored. This cross-sectional study used a body composition monitor to evaluate lean tissue mass and fat tissue mass. IR was calculated using homeostatic model assessment-insulin resistance (HOMA-IR). Eight pairs of 16S rRNA gene primers specific to Firmicutes, Bacteroidetes, Clostridium leptum group, Faecalibacterium prausnitzii, B acteroides, Bifidobacterium, Akkermansia muciniphila, and Escherichia coli were utilized to measure their abundance by qPCR. One hundred and fifty-four T2D patients were enrolled and stratified by the median HOMA-IR (2.5) and body mass index (BMI) of 25 kg/m2. A lower abundance of A. muciniphila was found in T2D patients with high HOMA-IR and BMI respectively. HOMA-IR and BMI had a synergistic effect on the reduction of the abundance of A. muciniphila. After adjusting metabolic factors, the low abundance of A. muciniphila significantly increased the risk for greater severity of IR. Furthermore, the negative correlation between A. muciniphila and IR was only found in T2D patients with high lean tissue. In conclusion, decreased abundance of fecal A. muciniphila enhanced the severity of IR in Asians with T2D, especially those having lean mass, and this significant relationship was independent of obesity.

Nutrients Intakes From Complementary Foods Are Associated With the Cardiometabolic Profile of 3-5-Year-Old Peruvian Amazonian Children

ObjectivesCharacterize relationships between dietary patterns and the cardiometabolic profile of Peruvian children at risk of undernutrition. MethodsThe study was nested in the Peru site of the ‘MAL-ED’ study, a longitudinal birth cohort to evaluate relationships between diet, enteric exposures and child growth and development. Dietary recalls were collected from 9–24 months of age. At 3–5 years, we conducted a follow-up. Three additional dietary recalls were collected, and blood pressure, height, weight, subscapular skinfolds, and fasting plasma glucose, insulin, and lipid profiles were assessed. Nutrient intakes were expressed as average density per 100 kcals i) from 9–24 months, and ii) at follow-up. Reduced rank regression (RRR) was used to identify the combination of nutrient intakes explaining the greatest variation in the outcome variables. Multiple linear regression models adjusting for subscapular skinfold-for-age Z-scores (SSFZ) were used to test whether observed relationships were mediated by body composition. ResultsOf the 153 children included, 26% were stunted at follow-up. RRR extracted 2 factors explaining 7% of the variation in infant nutrient intakes and 12% of the variation in response variables. The first factor had higher loadings for vitamin D, calcium, and cholesterol, while the second had higher loadings for non-animal source protein and iron. RRR also extracted 2 factors from the child intake data. These factors had higher loadings for sugar and fats, and sugar and protein, respectively. The first infant RRR factor was associated with lower plasma triglycerides and higher high-density lipoprotein, whereas the second was associated with higher homeostatic model assessment-insulin resistance (HOMA-IR) and weight-for-height Z-scores (WHZ). The first child RRR factor was associated with higher triglycerides, HOMA-IR, and WHZ, and the second was related to higher blood pressure. Associations with glucose and insulin, but not blood pressure or cholesterol, were attenuated after adjusting for SSFZ. ConclusionsNutrient densities of the diet in each childhood are associated with cardiometabolic profile in a chronically undernourished population. Funding SourcesThe project was supported by the Thrasher Foundation and the BMGF.

Non-genetic biomarkers and colorectal cancer risk: Umbrella review and evidence triangulation.

Several associations between non‐genetic biomarkers and colorectal cancer (CRC) risk have been detected, but the strength of evidence and the direction of associations are not confirmed. We aimed to evaluate the evidence of these associations and integrate results from different approaches to assess causal inference. We searched Medline and Embase for meta‐analyses of observational studies, meta‐analyses of randomized clinical trials (RCTs), and Mendelian randomization (MR) studies measuring the associations between non‐genetic biomarkers and CRC risk and meta‐analyses of RCTs on supplementary micronutrients. We repeated the meta‐analyses using random‐effects models and categorized the evidence based on predefined criteria. We described each MR study and evaluated their credibility. Seventy‐two meta‐analyses of observational studies and 18 MR studies on non‐genetic biomarkers and six meta‐analyses of RCTs on micronutrient intake and CRC risk considering 65, 42, and five unique associations, respectively, were identified. No meta‐analyses of RCTs on blood level biomarkers have been found. None of the associations were classified as convincing or highly suggestive, three were classified as suggestive, and 26 were classified as weak. For three biomarkers explored in MR studies, there was evidence of causality and seven were classified as likely noncausal. For the first time, results from both observational and MR studies were integrated by triangulating the evidence for a wide variety of non‐genetic biomarkers and CRC risk. At blood level, lower vitamin D, higher homeostatic model assessment‐insulin resistance, and human papillomavirus infection were associated with higher CRC risk while increased linoleic acid and oleic acid and decreased arachidonic acid were likely causally associated with lower CRC risk. No association was found convincing in both study types.

Different Criteria for the Definition of Insulin Resistance and Its Relation with Dyslipidemia in Overweight and Obese Children and Adolescents.

Purposeto compare cut off points corrected for age and gender (COOP) with fixed cut off points (FCOP) for fasting plasma insulin and Homeostatic model assessment-insulin resistance (HOMA-IR) for the diagnosis of IR in obese children and adolescents and their correlation with dyslipidemia.MethodsA multicenter, cross-sectional study including 383 subjects aged 7 to 18 years, evaluating fasting blood glucose, plasma insulin, and lipid profile. Subjects with high insulin levels and/or HOMA-IR were considered as having IR, based on two defining criteria: FCOP or CCOP. The frequency of metabolic abnormalities, the presence of IR, and the presence of dyslipidemia in relation to FCOP or CCOP were analyzed using Fisher and Mann-Whitney exact tests.ResultsUsing HOMA-IR, IR was diagnosed in 155 (40.5%) and 215 (56.1%) patients and, using fasting insulin, 150 (39.2%) and 221 (57.7%), respectively applying FCOP and CCOP. The use of CCOP resulted in lower insulin and HOMA-IR values than FCOP. Dyslipidemia was not related to FCOP or CCOP. Blood glucose remained within normal limits in all patients with IR. There was no difference in the frequency of IR identified by plasma insulin or HOMA-IR, both for FCOP and CCOP.ConclusionThe CCOP of plasma insulin or of HOMA-IR detected more cases of IR as compared to the FCOP, but were not associated with the frequency of dyslipidemia. As blood glucose has almost no fluctuation in this age group, even in the presence of IR, fasting plasma insulin detected the same cases of IR that would be detected by HOMA-IR.

Association between Insulin Resistance and Benign Prostatic Hyperplasia in Healthy Middle-aged Korean Men

Background: We examined the association between insulin resistance assessed by homeostatic model assessment-insulin resistance (HOMA-IR) and benign prostatic hyperplasia (BPH) in healthy middle-aged male subjects. Methods: A cross-sectional study included 1,727 male subjects, aged 40-59 year, free of medication history for BPH who received a transrectal ultrasonography and completed a structured questionnaire in 2011. Multiple logistic regression analysis was performed to evaluate the relationships of HOMA-IR with BPH across the tertile of HOMA-IR. Results: The prevalence of BPH was 24.4% (421 out of 1,727). It was increased across HOMA-IR tertiles in crude and age-adjusted models. In a multivariable-adjusted model after adjusting potential confounders such as age, body mass index (BMI), triglyceride, high density lipoprotein cholesterol (HDL-C), low density lipoprotein cholesterol (LDL-C), alcohol consumption, smoking, exercise and meat consumption, odds ratios (95% confidence intervals, CIs) of BPH for 2nd tertile and 3rd tertile compared to 1st tertile were 1.76 (1.31-2.35), and 1.83 (1.34-2.48), respectively. Conclusions: In middle-aged, healthy men, higher HOMA-IR was significantly associated with higher prevalence of BPH, supporting insulin resistance as an independent risk factor for BPH. Korean J Health Promot 2015;15(4):202-208

Comparison of insulin resistance and serum high-sensitivity C-reactive protein levels according to the fasting blood glucose subgroups divided by the newly recommended criteria for fasting hyperglycemia in 10 059 healthy Koreans

The increment for the prevalence of diabetes mellitus and impaired glucose tolerance warrants lowering the cutoffs of normoglycemia to help predict the future development of diabetes. The aim of this study was to find out whether insulin resistance and high-sensitivity C-reactive protein (hsCRP), a nontraditional cardiovascular risk factor, were related to the fasting glucose level, even in normoglycemic range that was categorized by the newly recommended criteria by the American Diabetes Association. Among the participants undergoing medical checkup program at Kangbuk Samsung Hospital, 10 059 subjects (5535 men and 4524 women; mean age, 45 years) with normal fasting glucose levels, as defined by the newly recommended criteria (<5.6 mmol/L), were enrolled in this study. The blood pressures, body mass index (BMI), fasting blood glucose, fasting insulin, lipid batteries, and hsCRP levels were checked. The homeostatic model assessment–insulin resistance (HOMA-IR) and the quantitative insulin sensitivity check indexes (QUICKI) were calculated. All subjects were subdivided into 4 groups according to the fasting glucose level. The HOMA-IR, QUICKI, and log-transformed (log) hsCRP, or log(hsCRP), level significantly increased according to the increment in fasting glucose, and these associations were consistent after adjustment for age and BMI, except for the log(hsCRP) ( P = .124 after adjustment). Log(hsCRP) increased as the HOMA-IR increased and as the QUICKI decreased, and when multiple regression analysis was done with log(hsCRP) as the dependent variable, age, high BMI, male sex, high HOMA-IR, hypertriglyceridemia, and low high-density lipoprotein cholesterol were the significant predictor for log(hsCRP). In conclusion, the insulin resistance indexes and hsCRP increased gradually even in the normal fasting glucose range, as categorized by the newly recommended criteria for abnormal fasting glucose levels, supporting the rationale for expanding the range of fasting hyperglycemia.