A large proportion of prediabetes and diabetes goes undiagnosed when only fasting plasma glucose and/or HbA1c are measured in overweight or obese patients

AimsThe purposes of the study were to determine the prevalence of unrecognized dysglycaemia in overweight (body mass index [BMI] 25–29.9 kg/m²) and obese (BMI ≥30 kg/m²) patients, to assess the extent to which measures of fasting plasma glucose (FPG) and/or HbA_1c, compared with oral glucose tolerance tests (OGTTs), misdiagnose dysglycaemia, and to determine the factors associated with an isolated abnormal post-OGTT glucose value.MethodsOGTT was performed and HbA_1c was measured in 1283 inpatients with BMI scores ≥25 kg/m² and no history of dysglycaemia.ResultsPrediabetes was found in 257 (20.0%) subjects (197 with impaired glucose tolerance, 29 with impaired fasting glucose, 31 with both) and diabetes in 77 (6.0%), including 22 with FPG ≥7 mmol/L (WHO definition). The sensitivity of FPG >6 mmol/L, FPG >5.5 mmol/L, HbA_1c ≥6% and the recommendations of the French National Agency of Accreditation and Evaluation in Health Care (ANAES) to identify patients with abnormal OGTTs was 29.9, 41.3, 36.8 and 15.6%, respectively. The factors that were independently associated with diabetes in obese women with FPG <7 mmol/L were age (per 10 years: OR 1.54 [1.00–2.11]; P = 0.049) and FPG (OR 6.1 [1.4–30.0]; P = 0.014), whereas age (OR 1.26 [1.09–1.44]; P < 0.01) and waist circumference (per 10 cm: OR 1.17 [1.01–1.33]; P < 0.05) were independently associated with dysglycaemia in obese women with FPG <6.1 mmol/L.ConclusionIn overweight and obese patients: dysglycaemia is commonly seen; FPG alone, compared with OGTT, failed to diagnose 70% of dysglycaemia cases; FPG >5.5 mmol/L and HbA_1c ≥6.0% are not necessarily substitutes for OGTT; and older age and larger waist circumference should be used to select those obese women with normal FPG who might further benefit from OGTTs to diagnose dysglycaemia.     

Measurement of muscle insulin sensitivity in obese men

AimsIn 2007, a novel estimate of skeletal muscle insulin sensitivity was derived from the oral glucose tolerance test (OGTT). The aim of this investigation is to assess whether and to what extent the proposed index of skeletal muscle insulin sensitivity derived from the OGTT was associated with muscle insulin sensitivity measured using the hyperinsulinemic-euglycaemic clamp technique.MethodsForty-six middle-aged, abdominally obese men (age 44 ± 8 years, waist circumference 107.4 ± 6.2) were studied. Each participant participated in a 2-hour, 75-g OGTT and a 3-hour hyperinsulinemic-euglycaemic clamp protocol.ResultsThe OGTT-derived index of muscle insulin sensitivity correlated with muscle insulin sensitivity measured with the insulin clamp (r = 0.55, P < 0.01), however, the standard error of estimate (SEE) when predicting muscle insulin sensitivity by the OGTT-derived index was 5.3 (50%).ConclusionOur findings suggest that despite a statistically significant association between the two methods, the OGTT approach lacks precision and is not a useful method for estimating skeletal muscle insulin sensitivity in abdominally obese men.     

Multiple short bouts of exercise over 12-h period reduce glucose excursions more than an energy-matched single bout of exercise

ObjectiveLong, uninterrupted bouts of sedentary behavior are thought to negatively influence postprandial glucose and insulin concentrations. We examined the effects of a 1-h bout of morning exercise versus intermittent walking bouts of short duration on glucose excursions and insulin secretion over 12-h.Materials/MethodsEleven young, obese individuals (18–35 years, BMI > 30 kg/m²) with impaired glucose tolerance were studied on three 12-h study days: 1) sedentary behavior (SED); 2) sedentary behavior with 1-h morning exercise (EX) at 60%–65% VO_2peak; and 3) sedentary behavior with 12-hourly, 5-min intervals of exercise (INT) at 60%–65% VO_2peak. Meals (1046 kJ/meal) were provided every 2-h. Blood samples were collected every 10 min and measured for glucose, insulin, and c-peptide concentrations.ResultsGlucose iAUC (12-h) was attenuated in the INT and SED conditions compared to the EX condition (P < 0.05). Glucose concentrations were higher in the EX compared to the SED condition for ~ 150 min (20% of the study day), and comparison of the EX-INT study days revealed that glucose concentrations were greater for ~ 240 min (~ 1/3 of the 12-h day). In the SED condition, the 12-h insulin iAUC was ~ 15% higher (P < 0.05) compared to the INT and EX conditions. Insulin production rate was found to increase ~ 20% with INT exercise vs. the SED and EX condition (P < 0.05).ConclusionsShort, frequent periods of exercise attenuated glucose excursions and insulin concentrations in obese individuals to a greater degree than an equal amount of exercise performed continuously in the morning.     

Exercise,fitness and cognition – A randomised controlled trial in older individuals: The DR's EXTRA study

BackgroundObservational studies suggest that higher levels of physical activity and cardiorespiratory fitness associate with improved cognition. However, evidence from randomised controlled trials (RCT) is limited. We hypothesised that increased regular exercise improves cognition in older individuals. The trial is registered: ISRCTN45977199 (http://isrctn.org).MethodsA population sample of 1335 men and women aged 57–78 years was randomised into aerobic exercise, resistance exercise, diet, combined aerobic exercise and diet, combined resistance exercise and diet or reference group for a 4-year intervention. Here, we report 2-year interim data. Exercise was assessed by a questionnaire and by maximal oxygen uptake (VO_2max), an objective measure of exercise, and cognition using Consortium to establish a registry for Alzheimer's disease (CERAD) neuropsychological tests.FindingsIn the intention to treat analyses, regular exercise increased in exercise groups, but remained unchanged in reference and diet only groups (P < 0.001 between groups). VO_2max remained unchanged in exercise groups, but decreased in reference and diet only groups (P < 0.001 between groups). There were between group differences neither in cognition, nor in the association of VO_2max to cognition during the first 2 years of intervention. In secondary analyses, improved VO_2max was associated with improved immediate memory in aerobic (β = 0.11, P = 0.001), resistance (β = 0.08, P = 0.018), diet (β = 0.09, P = 0.029) and combined aerobic and diet groups (β = 0.09, P = 0.013), with improved delayed memory in diet group (β = 0.08, P = 0.015) and with verbal performance in aerobic group (β = 0.14, P = 0.044). Those who were in the upper gender-specific VO_2max tertile had a 66.0% (95% confidence interval [CI] 34.2–82.4%, P = 0.001) lower, and those in the middle tertile a 56.4% (95% CI 22.6–75.4%, P = 0.005) lower risk of developing impaired delayed memory compared to those in the lower VO_2max tertile, after adjusting for potential confounders.ConclusionsPresent data from a large RCT among older individuals failed to show between group differences on the effects of regular exercise on cognition. However, secondary analyses suggest that higher levels of fitness may potentially mitigate memory impairment.     

Physical activity before and during pregnancy and risk of abnormal glucose tolerance among Hispanic women

AimWomen diagnosed with abnormal glucose tolerance and gestational diabetes mellitus are at increased risk for subsequent type 2 diabetes, with higher risks in Hispanic women. Studies suggest that physical activity may be associated with a reduced risk of these disorders; however, studies in Hispanic women are sparse.MethodsWe prospectively evaluated this association among 1241 Hispanic participants in Proyecto Buena Salud. The Pregnancy Physical Activity Questionnaire was used to assess pre, early, and mid pregnancy physical activity. Medical records were abstracted for pregnancy outcomes.ResultsA total of 175 women (14.1%) were diagnosed with abnormal glucose tolerance and 57 women (4.6%) were diagnosed with gestational diabetes. Increasing age and body mass index were strongly and positively associated with risk of gestational diabetes. We did not observe statistically significant associations between total physical activity or meeting exercise guidelines and risk. However, after adjusting for age, BMI, gestational weight gain, and other important risk factors, women in the top quartile of moderate-intensity activity in early pregnancy had a decreased risk of abnormal glucose tolerance (odds ratio = 0.48, 95% Confidence Interval 0.27–0.88, P_trend = 0.03) as compared to those in the lowest quartile. Similarly, women with the highest levels of occupational activity in early pregnancy had a decreased risk of abnormal glucose tolerance (odds ratio = 0.48, 95% Confidence Interval 0.28–0.85, P_trend = 0.02) as compared to women who were unemployed.ConclusionIn this Hispanic population, total physical activity and meeting exercise guidelines were not associated with risk. However, high levels of moderate-intensity and occupational activity were associated with risk reduction.     

Acute exercise improves postprandial cardiovascular risk factors in overweight and obese individuals

ObjectivesThe effects of 30 min of exercise on postprandial lipaemia in the overweight and obese are unknown as previous studies have only investigated bouts of at least 60 min in lean, healthy individuals. The aim of this study was to investigate whether a single 30-min bout of resistance, aerobic or combined exercise at moderate-intensity would decrease postprandial lipaemia, glucose and insulin levels as well as increase resting energy expenditure and increase fat oxidation following a high fat meal consumed 14 h after the exercise bout, in overweight and obese individuals compared to no exercise. We also compared the effects of the different exercise modalities.MethodsThis study was a randomized cross-over design which examined the postprandial effects of 30 min of different types of exercise in the evening prior to a breakfast meal in overweight and obese men and women. Participants were randomized on four occasions, each one-week apart, to each condition; either no exercise, aerobic exercise, resistance exercise or a combination of aerobic exercise and resistance exercise.ResultsAn acute bout of combination training did not have any significant effect on postprandial measurements compared to no exercise. However, aerobic exercise significantly reduced postprandial triglyceride levels by 8% compared to no exercise (p = 0.02) and resistance exercise decreased postprandial insulin levels by 30% compared to aerobic exercise (p = 0.01).ConclusionThese results indicate that a single moderate-intensity 30 min bout of aerobic or resistance exercise improves risk factors associated with cardiovascular disease in overweight and obese individuals.     

Effect of home-based exercise intervention on fasting insulin and Adipocytokines in colorectal cancer survivors: a randomized controlled trial

Background and AimsElevated circulating insulin is associated with increased risk of recurrence and cancer mortality in early-stage colorectal cancer (CRC). We conducted a randomized controlled trial to determine the effect of a 12-week home-based exercise program on fasting insulin, adipocytokines, and physical function in CRC survivors.MethodsOne hundred and twenty-three stage II-III CRC patients were randomly assigned to either a home-based exercise (n = 62) or standard care control group (n = 61) for 12 weeks. Home-based exercise consisted of aerobic and resistance training, with a goal of obtaining ≥ 18 metabolic equivalent task (MET)-h/wk. Participants in the exercise group were instructed to participate in > 18 MET-h/wk. of aerobic and resistance exercise while the participants in the control group were asked to maintain their usual daily activity. The primary outcome was fasting insulin levels. Secondary outcomes were adiponectin, TNF-α levels and 6 min walk distance from baseline to post-intervention.ResultsAfter the 12-weeks, moderate-vigorous physical activity participation increased from 9.1 ± 14.7 MET-h/wk. to 26.6 ± 21.7 MET-h/wk. in the exercise group, with no change in the control group (p < 0.01 for group and time interaction). Circulating insulin level decreased by 1 μU/ml (6.0 ± 3.9 vs. 5.0 ± 3.5, p = 0.009) in the exercise group with no change in the control group (p = 0.022 for group and time interaction). A similar trend was observed in TNF-α (p = 0.030 for group and time interaction). Six minute walk distance increased by 25.2 m in the exercise group with no change in the control group (p = 0.061 for group and time interaction).ConclusionsThe 12 week home-based exercise program increased level of physical activity and decreased circulating insulin levels in CRC survivors.     

The change in one-hour postload plasma glucose levels,and an analysis of its related factors in abdominally obese Han Chinese men with normal glucose tolerance

ObjectiveThis study was to observe the difference in one-hour postload plasma glucose levels and analyze its related factors in abdominally obese men with normal glucose tolerance (NGT).DesignThis case–control study included 36 abdominally obese men (waist circumference ≥ 90 cm) and 31 non-abdominally obese men (waist circumference < 90 cm) aged 20–50 years with NGT. Cases and controls were matched in age. All subjects underwent oral glucose tolerance test with 75 g of oral anhydrous glucose.Results0.5 and 1-h postload plasma glucose levels were higher in abdominally obese group than in non-abdominally obese group (P < .05). Fasting plasma glucose (FPG), 2 and 3-h postload plasma glucose were similar in the two groups (P > .05). 1-h postload plasma glucose was positively correlated with body mass index (r = 0.454), waist circumference(WC) (r = 0.519), systolic blood pressure (r = 0.456), diastolic blood pressure (r = 0.338), triglycerides (r = 0.439), and negatively correlated with high density lipoprotein cholesterol (r = ? 0.391), 1/fasting insulin (r = ? 0.459), insulinogenic index (r = ? 0.357) and disposition index (r = ? 0.602) (P < .01). In multiple regression analysis, 1-h postload plasma glucose maintained an independent association with disposition index (β = ? 1.367, P = .000), WC (β = 0.103, P = .000) and triglycerides (β = 0.185, P = .017).ConclusionsThe present study demonstrated that the level of one-hour postload plasma glucose was elevated in abdominally obese men with NGT. Besides FPG and 2-h postload plasma glucose, we must also pay attention to the measurement of one-hour postload plasma glucose. Disposition index, WC and triglycerides were independently related factors for elevated one-hour postload plasma glucose.     

Validation of a simple index (SIisOGTT) of insulin sensitivity in a population of sedentary men

AimThe ongoing obesity epidemic is associated with numerous health problems related to altered metabolic function. Among these is type 2 diabetes, characterized by lowered insulin sensitivity (IS). Consequently, the development of simple indices to assess IS has research and clinical importance. The SI_isOGTT, a new index of IS, was recently described by Bastard et al. (Diabetes & Metabolism 2007;33:261–8), and validated in sedentary, non-diabetic, overweight and obese postmenopausal women. The aim of the present study was to validate the index in men.MethodsThe data used in this project came from sedentary men (n = 36), aged 34–53 years, all of whom underwent a hyperinsulinaemic–euglycaemic clamp and 2-hour oral glucose tolerance test (OGTT). Correlations with M/I (glucose infusion rate [GIR] divided by insulin concentration), GIR and GIR divided by fat-free mass (FFM) were obtained by four well-known indices (HOMA, QUICKI, Cederholm and Matsuda) as well as with the new SI_isOGTT index. Pearson correlations and Bland–Altman analyses were obtained for every index versus clamp value.ResultsThe best correlate of IS in the present study was the SI_isOGTT (r = 0.84, P < 0.0001). The agreement of this method with the hyperinsulinaemic–euglycaemic clamp, as assessed by Bland–Altman plots, was similar to those of the other indices and to those previously described in postmenopausal women.ConclusionThe new index proposed by Bastard et al. is as good a predictor of IS in sedentary men as the other commonly used indices, and appears to be as reliable in this population as it was in the original study of postmenopausal women.     

Studying progression from glucose intolerance to type 2 diabetes in obese children

AimIdentification of metabolic and genetic factors capable to mediate progression from normal glucose tolerance (NGT) through impaired glucose tolerance (IGT) to type 2 diabetes (T2D) in childhood obesity.Patients and methodsThree groups of obese children with NGT (n = 54), IGT (n = 35), and T2D (n = 62) were evaluated. A control group of non-obese normal children (n = 210) was also studied. In obese patients, an oral glucose tolerance test (OGTT) was performed. Insulin resistance (IR) was assessed using HOMA-IR index. Insulin sensitivity (IS) was assessed according to the Matsuda formula. Genomic DNA from obese and control children was genotyped for genetic variants of PPARG, ADIPOQ, ADIPOR1, FTO, TCF7L2, and KCNJ11 using a real-time PCR strategy. The unpaired Student's t-test and Kruskal–Wallis one-way test were used to compare quantitative data in two and more groups. To assess the extent to which the various genetic variants were associated with pathology, ORs (odds ratios) and 95% CI (confidence interval) were estimated.ResultsIn T2D children, HOMA-IR value (7.5 ± 3.1) was significantly (P < 0.001) higher than that in IGT (4.21 ± 2.25) and NGT (4.1 ± 2.4) subjects. The Matsuda IS index was significantly increased in normoglycemic patients compared to IGT individuals (2.8 ± 1.75 vs. 2.33 ± 1.2, P < 0.05). The Pro12Ala polymorphism of PPARG was significantly associated with obesity (OR = 1.74, 95% CI = 1.19–2.55, P = 0.004) and T2D in obesity (OR = 2.01, 95% CI = 1.24–3.26, P = 0.004).ConclusionIR is a major risk factor that mediates progression from NGT to clinical T2D in Russian obese children. This progression may be genetically influenced by the Pro12Ala variant of PPARG.     

Effectiveness of an aerobic walking program using heart rate monitor and pedometer on the parameters of diabetes control in Asian Indians with type 2 diabetes

AimsTo analyze the effects of 8 weeks of aerobic walking using a heart rate monitor (HRM) and pedometer for monitoring exercise intensity on glycemic outcomes, fasting blood glucose (FBG), cardiovascular fitness and well-being in type 2 diabetes patients.MethodsForty adults with type 2 diabetes were randomly allocated to an 8-week supervised program of walking using heart rate monitor and pedometer (group A = 20) and control group (group B = 20). All outcomes were determined at baseline and after the 8-week training period.ResultsThe exercise training program resulted in a 9.7% (P < 0.05) improvement in group A. Fasting blood glucose level decreased significantly by 37% in group A (P < 0.05). Body mass index (BMI) ratio decreased by 3.9% in group A and increased by 2.2% in group B. General well-being (GWB) improved by 28.8% (P < 0.05) in the exercising group and there was an improvement in all parameters associated with cardiovascular health.ConclusionMonitoring an exercise program using a heart rate monitor and pedometer was effective and decreased the level of HbA1c, FBG, BMI and improved general well-being. Further using HRM helped us to attribute all improvements to the exercise intensity that we used in our study.     

Association between circadian rhythm of blood pressure and glucose tolerance status in normotensive,non-diabetic subjects

AimsTo examine whether circadian rhythm of blood pressure (BP) is associated with glucose tolerance status in normotensive, non-diabetic subjects.MethodsA cross-sectional study recruited normotensive and non-diabetic subjects, aged 35–79 years. A 75 g oral glucose tolerance test (OGTT) and 24-h ambulatory blood pressure monitoring (24-h ABPM) were performed.ResultsAmong 31 impaired glucose tolerance (IGT) and 36 normal glucose tolerance (NGT) study subjects, the mean (±S.D.) diurnal–nocturnal differences of average systolic BP (SBP) were 7.1 ± 6.9 and 9.9 ± 6.2 mm Hg, respectively (p = 0.086). In a linear mixed-effects regression model, however, taking each measurement of BP as the outcome, nighttime reduction of SBP in the IGT group was 7.19 mm Hg, which was significantly smaller compared to a reduction of 9.80 mm Hg in the NGT group (p-value for IGT: nighttime interaction = 0.0014). The prevalence of non-dipping BP pattern was 77.4% in the IGT group which was significantly higher than 52.8% of the NGT group (p = 0.036). Logistic regression revealed a significant effect of IGT for predicting non-dipping pattern with an adjusted odds ratio of 3.71 (95% CI: 1.09, 12.66, p = 0.029).ConclusionsAmong normotensive, non-diabetic subjects, the decreased nocturnal BP reduction was associated with impaired glucose tolerance status.     

Irisin and leptin concentrations in relation to obesity,and developing type 2 diabetes: A cross sectional and a prospective case-control study nested in the Normative Aging Study

ObjectiveTo investigate the associations between irisin and leptin levels in obesity and insulin resistance in a cross sectional study. To assess the potential role of irisin and leptin as a predictive marker of T2DM using a nested case-control study.MethodsBoth studies were designed within the longitudinal VA NAS cohort. The cross sectional study involved 111 non obese and 105 obese subjects who were subdivided into two groups based on their fasting glucose tolerance. In the nested 1:3 case-control study, 47 subjects with T2DM and 140 non-diabetic controls were selected. Serum samples collected 3-5 years before the diagnosis of T2DM were analyzed. Irisin and leptin concentrations were measured using a validated ELISA and radioimmunoassay respectively.ResultsIn the cross-sectional study, irisin did not differ between groups based on their fasting glucose tolerance. When subjects were grouped based on obesity status, both irisin and leptin concentrations were significantly higher in obese compared to the non-obese group (p = 0.03 and < 0.001, respectively). Irisin concentrations positively correlated with leptin concentrations (r = 0.392, P < 0.001). In the nested case control study, leptin concentrations were a significant predictor of developing diabetes (p = 0.005) in unadjusted models, but not after correcting for BMI, whereas irisin concentrations did not play a role of comparable significance.ConclusionsLeptin concentrations are higher in the obese group irrespective of their glucose tolerance. Obese individuals with impaired fasting glucose have higher concentrations of circulating irisin compared to non-obese subjects with normal glucose tolerance. Irisin concentrations do not predict risk of developing diabetes prospectively.     

Interleukin-20 circulating levels in obese women: Effect of weight loss

Background and aimsObesity is associated with an increased risk of developing atherosclerosis. Interleukin-20 (IL-20) is a pleiotropic cytokine thought to be involved in the onset and progression of atherosclerosis. The aim of this study was to determine whether circulating levels of IL-20 are elevated in obese women and whether they could be affected by a substantial decrease in body weight.Methods and resultsFifty obese and 50 age-matched, normal weight, premenopausal women participated in the study. Obese women entered into a medically supervised weight loss program aimed at reducing body weight to 90% of baseline. We measured anthropometric, glucose and lipid parameters, and IL-20, C-Reactive Protein (CRP) and interleukin-10 (IL-10) circulating levels. Circulating IL-20 and CRP levels were significantly higher in obese than control women (P = 0.01), while IL-10 levels were significantly lower; IL-20 levels were positively associated with body weight (r = 0.35; P = 0.02) and visceral fat (waist–hip ratio; r = 0.32; P = 0.025). Caloric restriction-induced weight loss (>10% of original weight) over 6 months reduced IL-20 levels from 152 (112/184) to 134 (125/153) pg/ml (median and 25%/75%; P = 0.03), and it was positively associated with changes in body mass index and waist–hip ratio.ConclusionIn premenopausal obese women, IL-20 levels are higher than matched normal weight control women, are associated with body weight and waist–hip ratio, and are reduced by weight loss.     

Autonomic function is not associated with the incidence of type 2 diabetes in a high-risk population: The Hoorn study

AimImpaired autonomic function is a complication of type 2 diabetes mellitus (DM2), but may also be involved in its development. For this reason, this study looked at the association of autonomic function with the incidence of DM2 in a homogeneous Caucasian population.MethodsThis Hoorn study was a prospective population-based study of individuals aged 50–75 years. For the 631 participants, the standard deviation of all normal-to-normal intervals (SDNN) and eight other parameters of autonomic function were calculated at baseline. Fasting and 2-h glucose were measured during follow-up by oral glucose tolerance test (OGTT). DM2 at baseline and follow-up was ascertained by questionnaire and OGTT. After excluding participants with DM2 at baseline, the association of parameters of autonomic function with incident diabetes was examined using logistic-regression analysis while adjusting for possible confounders.ResultsAfter excluding those with known (n = 67) or newly diagnosed (n = 126) DM2 at baseline and those missing follow-up data (n = 140), 298 participants were eligible for the study (182 with normal glucose tolerance, 19 with impaired fasting glucose and 97 with impaired glucose tolerance). During a median follow-up of 9.2 (range 4.5–11.1) years, 94 incident cases of DM2 were observed. After adjusting for confounding variables, the DM2 odds ratio was 1.12 (95% CI: 0.77, 1.64) per SDNN increase. Results for other parameters of autonomic function were similar.ConclusionThe present study found no evidence of an association between autonomic function and DM2 incidence in a population at high risk of diabetes. This implies that previously observed associations between autonomic function and glucose metabolism in cross-sectional settings may reflect reverse causation.     

Effect of Exercise Therapy on Monocyte and Neutrophil Counts in Overweight Women

IntroductionIt has been well known that physical inactivity is associated with a significantly higher incidence of coronary artery disease. This study aimed to test our hypothesis that endurance aerobic exercise training has cardiovascular protective effects as a result of inhibiting inflammatory processes.MethodsForty-two overweight women [age, 53.4 ± 9.8 years; body mass index (BMI), 28.0 ± 2.8] received electric bicycle ergometer exercise therapy at the lactate threshold intensity for 30 to 60 minutes per day, 1 to 6 times per week for 6 weeks. The exercise training was performed within the possible load (exercise duration and frequency) for each subject.ResultsLeukocyte, monocyte, and neutrophil counts significantly decreased after the exercise therapy (P < 0.05). In simple regression analysis, percent changes in monocyte and neutrophil counts were correlated with percent changes in fasting triglyceride levels, insulin sensitivity index, BMI, and maximal oxygen uptake (VO₂max). In stepwise multiple regression analysis, the percent change in monocyte counts was associated with percent changes in fasting triglyceride and VO₂max (r² = 0.368, P < 0.001), and the percent change in neutrophil counts was associated with percent changes in insulin sensitivity index and BMI (r² = 0.292, P < 0.001).ConclusionsEndurance aerobic exercise training can influence some inflammatory processes. Furthermore, increased aerobic capacity may be antiinflammatory and have cardiovascular protective effects in overweight women.     

SHBG levels correlate with insulin resistance in postmenopausal women

BackgroundOverweight or central obesity is generally associated with increases in fasting insulin levels, insulin resistance, and glucose intolerance and has been identified as a target for new therapeutic strategies, including early change in lifestyle. Early biochemical markers for identifying at-risk patients will be useful for prevention studies. The aim of this study is to investigate whether or not SHBG level is a useful index of hyperinsulinemia and/or insulin resistance in pre- and postmenopausal obese women. At the same time, the relationship between SHBG concentrations and features of the metabolic syndrome were evaluated.Methods229 women were eligible for this study. MetS was defined by using a modification of the ATP III guidelines. All patients were euthyroid, obese and overweight, 25 to 69 years of age. Subjects were divided into groups of premenopausal women (n = 125) and postmenopausal women (n = 104). Various fatness and fat distribution parameters, SHBG, sex hormones, FSH, LH, thyroid hormones, serum levels of fasting and postprandial glucose, lipid profile, uric acid and serum insulin, and blood pressure were measured.ResultsNo significant difference was found in mean SHBG levels between pre- and postmenopausal obese women in this study (p = 0.866).In premenopausal obese women, SHBG correlated negatively with BMI, waist circumference, fasting glucose, uric acid levels and FAI.In postmenopausal obese women, SHBG correlated negatively with fasting glucose, postprandial plasma glucose, fasting insulin, HOMA-IR and FAI and positively with HDL.SHBG had a significant inverse association with MetS parameters only in postmenopausal women, also after adjusting for BMI, age and estradiol.ConclusionsObesity may influence the levels of endogenous sex steroid, especially after menopause. SHBG concentrations are correlated with features of the metabolic syndrome, particularly in postmenopausal obese women.These results suggest that SHBG may be an index of insulin resistance in postmenopausal obese women.     

Moderate intensity sports and exercise is associated with glycaemic control in women with gestational diabetes

AimTo assess the association of regular, unsupervised sports and exercise during pregnancy, by intensity level, with glycaemic control in women with gestational diabetes (GDM).MethodsProspective cohort study of 971 women who, shortly after being diagnosed with GDM, completed a Pregnancy Physical Activity Questionnaire assessing moderate and vigorous intensity sports and exercise in the past 3 months. Self-monitored capillary glucose values were obtained for the 6-week period following the questionnaire, with optimal glycaemic control defined ≥ 80% values meeting the targets < 5.3 mmol/L for fasting and < 7.8 mmol/L 1-hour after meals. Logistic regression estimated the odds of achieving optimal control; linear regression estimated activity level-specific least square mean glucose, as well as between-level mean glucose differences.ResultsFor volume of moderate intensity sports and exercise ([MET × hours]/week), the highest quartile, compared to the lowest, had significantly increased odds of optimal control (OR = 1.82 [95% CI: 1.06–3.14] P = 0.03). There were significant trends for decreasing mean 1-hour post breakfast, lunch and dinner glycaemia with increasing quartile of moderate activity (all P < 0.05). Any participation in vigorous intensity sports and exercise was associated with decreased mean 1-hour post breakfast and lunch glycaemia (both P < 0.05). No associations were observed for fasting.ConclusionHigher volumes of moderate intensity sports and exercise, reported shortly after GDM diagnosis, were significantly associated with increased odds of achieving glycaemic control. Clinicians should be aware that unsupervised moderate intensity sports and exercise performed in mid-pregnancy aids in subsequent glycaemic control among women with GDM.     

Glucose tolerance and free fatty acid metabolism in adults with variations in TCF7L2 rs7903146

ObjectiveTCF7L2 variant rs7903146 is associated with increased risk for type 2 diabetes. We investigated the effect of TCF7L2 variant rs7903146 and glucose tolerance on free fatty acid (FFA) metabolism.Research Design and MethodsWe recruited 120 individuals, half homozygous for the major CC allele and half homozygous for the minor TT allele at rs7903146; each underwent a 2-h, 75 g oral glucose tolerance test (OGTT). Plasma glucose, insulin and free fatty acid concentrations were measured on blood collected before and during the OGTT.ResultsTotal FFA concentrations and percent FA species during OGTT were not different in CC and TT carriers when males and females were considered together. However, monounsaturated fatty acid (MUFA) concentrations and percentages were greater in TT than CC females during the OGTT. TT carriers with high HOMA-IR had significantly greater fasting FFA concentrations, lower disposition index (DI) and greater AUC of glucose than high HOMA-IR CC carriers, whereas no such differences were observed in the low HOMA-IR group. We found that fasting (826 ± 25 vs. 634 ± 22 μmol/L, P < 0.0001) and OGTT plasma FFA concentrations were greater in IGT than NGT subjects, and the difference remained after adjusting for sex, age, BMI, and genotype. Finally, IGT subjects had greater MUFA concentrations and percentages than NGT subjects during OGTT.ConclusionsDespite similar fasting insulin and glucose, fasting plasma FFA are greater in IGT than NGT adults. Insulin resistance and sex influence plasma FFA responses amongst carriers of the minor T allele of TCF7L2 rs7903146.     

Perceived psychosocial stress and glucose intolerance among pregnant Hispanic women

AimPrior literature suggests a positive association between psychosocial stress and the risk of diabetes in non-pregnant populations, but studies during pregnancy are sparse. We evaluated the relationship between stress and glucose intolerance among 1115 Hispanic (predominantly Puerto Rican) prenatal care patients in Proyecto Buena Salud, a prospective cohort study in Western Massachusetts (2006–2011).MethodsCohen's Perceived Stress Scale (PSS-14) was administered in early (mean = 12.3 weeks gestation; range 4.1–18 weeks) and mid- (mean = 21.3 weeks gestation; range 18.1–26 weeks) pregnancy. Participants were classified as having a pregnancy complicated by gestational diabetes mellitus, impaired glucose tolerance, and abnormal glucose tolerance, based on the degree of abnormality on glucose tolerance testing between 24 and 28 weeks of gestation.ResultsThe prevalence of gestational diabetes mellitus, impaired glucose tolerance, and abnormal glucose tolerance was 4.1%, 7.2%, and 14.5%, respectively. Absolute levels of early or mid-pregnancy stress were not significantly associated with glucose intolerance. However, participants with an increase in stress from early to mid-pregnancy had a 2.6-fold increased odds of gestational diabetes mellitus (95% confidence intervals: 1.0–6.9) as compared to those with no change or a decrease in stress after adjusting for age and pre-pregnancy body mass index. In addition, every one-point increase in stress scores was associated with a 5.5 mg/dL increase in screening glucose level (β = 5.5; standard deviation = 2.8; P = 0.05), after adjusting for the same variables.ConclusionIn this population of predominantly Puerto Rican women, stress patterns during pregnancy may influence the risk of glucose intolerance.