Trimester-specific reference intervals for thyroid function parameters in pregnant Caucasian women using Roche platforms: a prospective study

BACKGROUND

Standard thyroid function parameters reference intervals (RI) are unsuitable during pregnancy, potentially resulting in incongruous treatments that may cause adverse effects on pregnancy outcomes. We aimed at defining trimester-specific TSH, FT4 and FT3 RI, using samples longitudinally collected from healthy Caucasian women.

MATERIALS AND METHODS

Blood samples from 150 healthy Caucasian women, who had a physiological gestation and a healthy newborn at term, were collected in each trimester and at around six months post-partum. They showed mild iodine deficiency. After excluding women with overt TSH abnormalities (> 10 mU/L) and/or TPO antibodies, data from 139 pregnant women were analyzed by means of widely used Roche platforms, and TSH, FT4 and FT3 trimester-specific RI were calculated. Post-partum data were available for 55 subjects.

RESULTS

Serum TSH RI were 0.34-3.81 mU/L in the first trimester, and changed slightly to 0.68-4.07 U/L and 0.63-4.00 mU/L in the second and third trimester, respectively. Conversely, both FT4 and FT3 concentrations progressively decreased during pregnancy, the median values in the third trimester being 14.8% and 13.2% lower, respectively, than in the first trimester. Thyroid function parameters in the first trimester were similar to those measured after the end of pregnancy.

CONCLUSIONS

This study calculates trimester-specific RI for thyroid function parameters in pregnancy, and proposes the reference limits that should be adopted when using Roche platforms in Caucasian women.

Serum HMGB1 levels are independently associated with glucose clamp-derived measures of insulin resistance in women with PCOS

PURPOSE

PCOS is associated with low grade inflammation which could play a role in insulin resistance and ovarian dysfunction. Preliminary findings suggested that serum levels of HMGB1, a cytokine involved in inflammation, might be altered in women with PCOS. Primary aim of this study was to assess whether HMGB1 serum concentrations are associated with PCOS and with the state of insulin resistance of these women.

METHODS

Sixty women with PCOS, selected to have a similar proportion of subjects with altered or normal insulin sensitivity, and 29 healthy controls were studied. Serum HMGB1 levels were compared in subgroups of PCOS women and controls. In PCOS women, insulin sensitivity was assessed by the glucose clamp technique and HMGB1 was measured at baseline and after acute hyperinsulinemia.

RESULTS

HMGB1 levels were similar in women with PCOS and controls and no elements used for diagnosing PCOS were associated with serum HMGB1. However, HMGB1 concentrations were higher in insulin-resistant vs insulin-sensitive PCOS women (p = 0.017), and inversely associated with insulin-induced total and non-oxidative glucose metabolism. In both subgroups of PCOS women, serum HMBG1 levels significantly increased after acute hyperinsulinemia.

CONCLUSIONS

These data suggest that HMGB1 levels are not associated with PCOS per se, but with insulin resistance. Further research should establish the underlying nature of this relationship, and whether this protein might play a role in the metabolic complications of PCOS.

Circadian and sex differences in post-ischemic vasodilation and reactive hyperemia in young individuals and elderly with and without type 2 diabetes

OBJECTIVE

Cardiovascular events show morning preference and sex differences, and are related to aging and type 2 diabetes. We assessed circadian variations and sex differences in vascular conductance (VC) and blood flow (BF) regulations following a brief bout of forearm ischemia.

METHODS

Young healthy individuals (H18-30) and elderly without (H50-80) and with type 2 diabetes (T2DM50-80) of both sexes were included. Forearm VC and BF, and mean arterial pressure (MAP) at baseline and following circulatory reperfusion were measured at 6 a.m. and 9 p.m.

RESULTS

In the morning compared to evening, following reperfusion, the VC and BF increments were similar in H18-30 (p>.71), but lower in H50-80 (p<.001) and T2DM50-80 (p<.01). VC and BF following circulatory reperfusion were higher in men than women in H18-30 (p<.001), but similar between sexes in the older groups (p>.23).

CONCLUSIONS

Forearm vasodilation following reperfusion is attenuated in the morning in the elderly, impairing BF towards an ischemic area. Diabetes does not affect the circadian regulation of VC and BF, but that of MAP. There are sex differences in VC and BF at baseline and after circulatory reperfusion at a young age, being greater in men, which disappear with aging without being affected by diabetes.

The physiological sonographic features of the ovary in healthy subjects: a joint systematic review and meta-analysis by the Italian Society of Gynecology and Obstetrics (SIGO) and the Italian Society of Endocrinology (SIE)

PURPOSE

There is a lack of uniformity in the definition of normal ovary ultrasound parameters. Our aim was to summarize and meta-analyze the evidence on the topic. Full-text English articles published through December 31, 2020 were retrieved via MEDLINE and Embase. Data available for meta-analysis included: ovarian follicular count, ovarian volume, and ovarian Pulsatility Index (PI) assessed by Doppler ultrasound.

METHODS

Cohort, cross-sectional, prospective studies with a single or double arm were considered eligible. Interventional studies were included when providing baseline data. Both studies on pre- and post-menopausal women were screened; however, data on menopausal women were not sufficient to perform a meta-analysis. Studies on pre-pubertal girls were considered separately. Eighty-one papers were included in the meta-analysis.

RESULTS

The mean ovarian volume was 6.11 [5.81-6.42] ml in healthy women in reproductive age (5.81-6.42) and 1.67 ml [1.02-2.32] in pre-pubertal girls. In reproductive age, the mean follicular count was 8.04 [7.26-8.82] when calculated in the whole ovary and 5.88 [5.20-6.56] in an ovarian section, and the mean ovarian PI was 1.86 [1.35-2.37]. Age and the frequency of the transducers partly modulated these values. In particular, the 25-30-year group showed the higher mean follicular count (9.27 [7.71-10.82]), followed by a progressive age-related reduction (5.67 [2.23-9.12] in fertile women > 35 years). A significant difference in follicular count was also found according to the transducer's upper MHz limit.

CONCLUSION

Our findings provide a significant input to improve the interpretation and diagnostic accuracy of ovarian ultrasound parameters in different physiological and pathological settings.

Circadian Variations in Sympathetic Vasoconstriction in Older Adults with and Without Type 2 Diabetes

INTRODUCTION

An impact of the sympathetic nervous system in the higher rate of cardiovascular events in the early morning compared to the evening has been claimed. Augmented sympathetic vasoconstriction increases cardiovascular risk by augmenting pulse pressure and cardiac afterload. Type 2 diabetes (T2DM) further increases sympathetic neurovascular transduction and cardiovascular risk.

AIM

We assessed whether peripheral vasoconstriction triggered by a standardized sympathetic stressor is augmented at 6am vs 9pm in adults between 50-80 years with type 2 diabetes (T2DM50-80) vs healthy ones (H50-80).

METHODS

Mean values of sympathetic vasoconstrictor responsiveness (SVR), vascular conductance (VC), brachial artery blood flow, and mean arterial pressure were measured on the contralateral forearm over two 5-minute bouts of rest and handgrip-mediated sympathetic stimulation, respectively.

RESULTS

Although baseline VC values were lower (p < 0.01) in the morning vs evening in both groups, SVR values in response to sympathoexcitation were similar in H50-80 (- 0.43 ± 12.44 vs - 2.57 ± 11.63 %, p = 0.73) and T2DM50-80 (+6.64 ± 10.67 vs +5.21 ± 7.64 %, p = 0.90), but higher (p < 0.01) in T2DM50-80 vs H50-80 at both day hours. Individuals with T2DM reported positive SVR values and VC change-scores, while healthy individuals reported statistically different (p < 0.02) negative SVR values and VC change-scores.

CONCLUSION

Peripheral vasoconstriction triggered by a standardized sympathetic stressor is similar between morning and evening, regardless of T2DM and different baseline VC values. However, peripheral vasoconstriction responsiveness is blunted in individuals with T2DM as handgrip-mediated sympathoexcitation induces vasodilation in the contralateral forearm in adults with T2DM and vasoconstriction in healthy age-matched controls, highlighting a neurovascular response altered by T2DM.

Accuracy of CGM Systems During Continuous and Interval Exercise in Adults with Type 1 Diabetes

BACKGROUND

continuous glucose monitoring systems (CGMs) play an important role in the management of T1D, but their accuracy may reduce during rapid glucose excursions. The aim of study was to assess the accuracy of recent rt-CGMs available in Italy, in subjects with T1D during 2 sessions of physical activity: moderate continuous (CON) and interval exercise (IE).

METHOD

we recruited 22 patients with T1D, on CSII associated or integrated with a CGM, to which a second different sensor was applied. Data recorded by CGMs were compared with the corresponding plasma glucose (PG) values, measured every 5 minutes with the glucose analyzer. To assess the accuracy of the CGMs, we evaluated the Sensor Bias (SB), the Mean Absolute Relative Difference (MARD) and the Clarke error grid (CEG).

RESULTS

a total of 2355 plasma-sensor glucose paired points were collected. Both average plasma and interstitial glucose concentrations did not significantly differ during CON and IE. During CON: 1. PG change at the end of exercise was greater than during IE (P = .034); 2. all sensors overestimated PG more than during IE, as shown by SB (P < .001) and MARD (P < .001) comparisons. Classifying the performance according to the CEG, significant differences were found between the 2 sessions in distribution of points in A and B zones.

CONCLUSIONS

the exercise affects the accuracy of currently available CGMs, especially during CON, suggesting, in this circumstance, the need to maintain blood glucose in a "prudent" range, above that generally recommended. Further studies are needed to investigate additional types of activities.

Circadian and sex differences in carotid-femoral pulse wave velocity in young individuals and elderly with and without type 2 diabetes

The incidence of cardiovascular events is higher in the morning than in the evening and differs between sexes. We tested the hypothesis that aortic stiffness, a compelling cardiovascular risk factor, increases in the morning than in the evening in young, healthy individuals between 18 and 30 years (H18–30) or in older individuals between 50 and 80 years, either healthy (H50–80) or with type 2 diabetes (T2DM50–80). Sex differences were also investigated. Carotid-femoral pulse wave velocity (cf-PWV) recorded via Doppler Ultrasound, blood pressure and heart rate were checked at 6 a.m. and 9 p.m., at rest and during acute sympathetic activation triggered by handgrip exercise. Cf-PWV values were lower in the morning compared to the evening in all groups (p < 0.01) at rest and lower (p = 0.008) in H18–30 but similar (p > 0.267) in the older groups during sympathetic activation. At rest, cf-PWV values were lower in young women compared to young men (p = 0.001); however, this trend was reversed in the older groups (p < 0.04). During sympathetic activation, the cf-PWV was lower in women in H18–30 (p = 0.001), similar between sexes in H50–80 (p = 0.122), and higher in women in T2DM50–80 (p = 0.004). These data do not support the hypothesis that aortic stiffness increases in the morning compared to the evening within any of the considered groups in both rest and sympathetic activation conditions. There are differences between the sexes, which vary according to age and diabetes status. In particular, aortic stiffness is higher in older women than in men with diabetes during acute stress.

Sympathetic-mediated blunting of forearm vasodilation is similar between young men and women

BACKGROUND

The in-vivo regulation of vascular conductance (VC) is a continuous balance between endothelial vasodilation and sympathetic vasoconstriction. Although women may report blunted sympathetic vasoconstriction along with higher endothelial vasodilation than men, it is currently unknown whether the interaction between vasoconstriction and vasodilation leads to different regulation of VC between sexes. This study assessed sex differences in sympathetic-mediated blunting of endothelial vasodilation after a brief period of ischemia and whether any restriction of vasodilation blunts tissue blood flow (BF) and re-oxygenation.

METHODS

13 young women and 12 young men underwent two 5-min forearm circulatory occlusions followed by reperfusion, one in basal conditions and the other during cold pressor test-induced sympathetic activation (SYMP). Brachial artery diameter and BF, mean arterial pressure, total peripheral resistance (TPR), and thenar eminence oxygenation were collected. Percent changes normalized to baseline values of forearm VC, brachial artery BF and flow-mediated dilation (FMD), TPR, and hand oxygenation after circulatory reperfusion were calculated.

RESULTS

TPR increased during SYMP in men (p = 0.019) but not in women (p = 0.967). Women showed a greater brachial artery FMD than men (p = 0.004) at rest, but sex differences disappeared after normalization to shear rate and baseline diameter (p > 0.11). The percent increases from baseline of peak and average forearm VC after circulatory reperfusion did not differ between sexes in basal conditions (p > 0.98) or during SYMP (p > 0.97), and were restrained by SYMP similarly in both sexes (p < 0.003) without impairing the hand re-oxygenation (p > 0.08) or average hyperemic response (p > 0.09).

CONCLUSIONS

Although women may report blunted sympathetic vasoconstriction than men when assessed separately, the similar sympathetic-mediated restriction of vasodilation suggests a similar dynamic regulation of VC between sexes. SYMP-mediated restrictions of the normal forearm vasodilation do not impair the average hyperemic response and hand re-oxygenation in both sexes.

Clinical Value of Serum Levels of 11-Oxygenated Metabolites of Testosterone in Women With Polycystic Ovary Syndrome

CONTEXT

Recent data suggested that 11-oxygenated androgens may be the preponderant circulating androgens in women with PCOS. However, the pathophysiological significance of these hormones remains unclear.

OBJECTIVE

The aim of this study was to evaluate the relationships between serum 11-OH testosterone (11-OHT) and 11-keto testosterone (11-KetoT) and clinical and biochemical hyperandrogenism, as well as the metabolic parameters, in women with PCOS.

METHODS

The main classic and 11-oxygenated androgens were measured by LC-MS/MS and direct equilibrium dialysis in 123 women with PCOS, diagnosed according to the Rotterdam criteria, and 38 healthy controls. Insulin sensitivity was assessed by hyperinsulinemic euglycemic clamp.

RESULTS

Serum 11-oxygenated androgens were higher in women with PCOS than in controls. Elevated levels of 11-OHT and 11-KetoT were found in 28.5% and 30.1% of PCOS women, respectively, whereas free testosterone (FT) was increased in 61.0% of them. Serum 11-oxygenated androgens showed a limited performance in recognizing women with classically defined hyperandrogenism. Unlike FT, 11-oxygenated androgens did not show significant relationships with anthropometric and metabolic parameters, except for a direct association with insulin sensitivity. In multivariable analysis, 11-OHT and 11-KetoT, directly, and FT, inversely, remained significant independent predictors of insulin sensitivity.

CONCLUSIONS

Serum levels of 11-oxygenated androgens are higher in women with PCOS than in controls. However, these hormones show a poor performance in recognizing women with hyperandrogenism, as currently defined. The relationships of these androgens with insulin sensitivity strongly differ from that of FT, suggesting a different role of classic and 11-oxygenated androgens in the pathophysiology of PCOS.

Insulin-Mediated Substrate Use in Women With Different Phenotypes of PCOS: the Role of Androgens

CONTEXT

Few studies have explored in vivo insulin action on substrate use in women with PCOS. In particular, no data are available in women with different PCOS phenotypes.

OBJECTIVE

The aim of the study was to evaluate insulin action on glucose (Gox) and lipid (Lox) oxidation, nonoxidative glucose metabolism (Gnonox), and serum free fatty acids (FFAs) in different PCOS phenotypes.

METHODS

Participants included 187 nondiabetic women with PCOS diagnosed according to the Rotterdam criteria. Data from a historical sample of 20 healthy women were used as reference values. Whole-body substrate use data were obtained by the hyperinsulinemic euglycemic clamp associated with indirect calorimetry. Serum androgens were assessed by liquid chromatography-mass spectrometry and equilibrium dialysis.

RESULTS

During hyperinsulinemia, the increase of Gox (ΔGox), Gnonox, as well as the suppression of Lox (ΔLox) and serum FFA (Δ% FFA) were altered in each PCOS phenotype. Moreover, Gnonox and Δ% FFA were lower in women with the classic phenotype than in those with the ovulatory or the normoandrogenic phenotypes, and ΔGox was lower in women with the classic than in those with the ovulatory phenotype. In multivariable analysis fat mass and free testosterone were independent predictors of ΔGox, Gnonox, and Δ% FFA, whereas only fat mass predicted ΔLox.

CONCLUSION

In women with PCOS, regardless of phenotype, insulin-mediated substrate use is impaired. This phenomenon is greater in individuals with the classic phenotype. Free testosterone plays an independent role in insulin action abnormalities in glucose and lipid metabolism.

Onset of Addison Disease appeared during the first trimester of a twin pregnancy: A case report

Addison Disease is an uncommon, life‐threatening condition affecting people at any age, including women during pregnancy. If left untreated, the disease can be rapidly fatal, but the prognosis is good if promptly recognized and hormones are replaced.

Circulating HMGB1 Levels Are Associated With Glucose Clamp-Derived Measures of Insulin Resistance in Women With PCOS

Context: High mobility group box 1 (HMGB1) is a nuclear constitutive and highly conserved mammalian protein which shows several important physiologic functions, playing a crucial role in local and systemic inflammation. It also seems to be implicated in the development of metabolic syndrome, whereas some in vitro and animal models and recent preliminary human studies suggested its potential role in polycystic ovary syndrome (PCOS) pathophysiology. In particular, some data suggested a potential role of HMGB1 in follicular maturation block. Moreover, increased blood and follicular fluid HMGB1 concentrations have been reported in PCOS women, showing a direct correlation with surrogate indexes of insulin-resistance (IR) (i.e. HOMA-IR).

Objective: The purpose of the present study was to investigate the relationships between serum HMGB1 levels and clinical, endocrine and metabolic parameters of PCOS patients.

Design and patients: Sixty women with PCOS, 30 with IR and 30 with normal insulin sensitivity (IS), and 30 healthy controls were included in the study. In these subjects, body fat was quantified by bioelectrical impedance; plasma HMGB1 levels were measured using a specific ELISA method (Tecan, Mannedorf, Switzerland); and serum androgens were measured by liquid chromatography/mass spectrometry and equilibrium dialysis. In PCOS women, IR was measured using the gold standard hyperinsulinemic-euglycemic clamp technique, combined with indirect calorimetry.

Results: HMGB1 levels did not differ between PCOS women and healthy controls (4.11 ± 3.22 vs 3.77 ± 2.50 ng/mL, respectively; p=0.61). Moreover, HMGB1 levels did not differ between PCOS phenotype subgroups. However, PCOS IR women showed higher levels of this protein as compared with PCOS IS (5.00 ± 3.53 vs 3.16 ± 2.59 ng/mL, respectively; p=0.017). In women with PCOS, HMGB1 levels were associated with several metabolic parameters, including IR measured by glucose utilization during the clamp (rho -0.37, p=0.005). This correlation was preserved after adjusting for potential confounding parameters, such as age, fat mass and serum free testosterone. HMGB1 levels did not change during glucose-clamp induced acute hyperinsulinemia, either in the whole cohort of patients or in IR and IS subgroups analyzed separately. Both in the whole population under study and in PCOS women, HMGB1 levels did not correlate with anthropometric parameters, hormonal features and ovarian morphology.

Conclusions: In women with PCOS, HMGB1 blood levels show an independent association with insulin resistance. However, no associations with other typical features of the syndrome were found. Further research is needed in order to establish whether this protein may play a role in the pathogenesis of PCOS.

Walking for subjects with type 2 diabetes: a systematic review and joint AMD/SID/SISMES evidence-based practical guideline

Aims

Regular exercise is considered a cornerstone in the management of type 2 diabetes mellitus (T2DM). It improves glucose control and cardiovascular risk factors, contributes to weight loss, and also improves general well-being, likely playing a role in the prevention of chronic complications of diabetes. However, compliance to exercise recommendations is generally inadequate in subjects with T2DM. Walking is the most ancestral form of physical activity in humans, easily applicable in daily life. It may represent, in many patients, a first simple step towards lifestyle changes. Nevertheless, while most diabetic patients do not engage in any weekly walking, exercise guidelines do not generally detail how to improve its use. The aims of this document are to conduct a systematic review of available literature on walking as a therapeutic tool for people with T2DM, and to provide practical, evidence-based clinical recommendations regarding its utilization in these subjects.

Data synthesis

Analysis of available RCTs proved that regular walking training, especially when supervised, improves glucose control in subjects with T2DM, with favorable effects also on cardiorespiratory fitness, body weight, and blood pressure. Moreover, some recent studies have shown that even short bouts of walking, used for breaking prolonged sitting, can ameliorate glucose profiles in diabetic patients with sedentary behavior.

Conclusions

There is sufficient evidence to recognize that walking is a useful therapeutic tool for people with T2DM. This document discusses theoretical and practical issues for improving its use.

Insulin resistance and PCOS: chicken or egg?

PCOS is a common and heterogeneous endocrine disorder in women of reproductive age, frequently associated with metabolic abnormalities. It was estimated that about 75% of these subjects have an impairment of insulin action, as measured by gold standard methods. While the relationship between insulin resistance and PCOS is consistently shown by a number of studies, the mechanisms underlying its primary origin still remains an unsolved issue. Insulin resistance and the associated hyperinsulinemia can induce both the endocrine and reproductive traits of PCOS. However, androgen excess, in turn, can impair insulin action, directly and/or through several changes occurring in different tissues. Body fat excess, which is another common feature in these women, can contribute to worsening the whole picture. Nevertheless, insulin resistance may also be found in many normal-weight individuals. Endocrine and metabolic abnormalities can develop in different moments, and probably there is fetal programming of these alterations. However, a number of vicious circles, with bidirectional relationships between androgen excess and insulin resistance, and with the contribution of several other factors, make it extremely difficult to understand where this process really originates. This review summarizes available evidence on this topic, in order to better understand the complex relationships linking hyperandrogenism and impaired insulin action in women with PCOS.

Walking for subjects with type 2 diabetes: A systematic review and joint AMD/SID/SISMES evidence-based practical guideline

AIMS

Regular exercise is considered a cornerstone in the management of type 2 diabetes mellitus (T2DM). It improves glucose control and cardiovascular risk factors, contributes to weight loss, and also improves general well-being, likely playing a role in the prevention of chronic complications of diabetes. However, compliance to exercise recommendations is generally inadequate in subjects with T2DM. Walking is the most ancestral form of physical activity in humans, easily applicable in daily life. It may represent, in many patients, a first simple step towards lifestyle changes. Nevertheless, while most diabetic patients do not engage in any weekly walking, exercise guidelines do not generally detail how to improve its use. The aims of this document are to conduct a systematic review of available literature on walking as a therapeutic tool for people with T2DM, and to provide practical, evidence-based clinical recommendations regarding its utilization in these subjects.

DATA SYNTHESIS

Analysis of available RCTs proved that regular walking training, especially when supervised, improves glucose control in subjects with T2DM, with favorable effects also on cardiorespiratory fitness, body weight and blood pressure. Moreover, some recent studies have shown that even short bouts of walking, used for breaking prolonged sitting, can ameliorate glucose profiles in diabetic patients with sedentary behavior.

CONCLUSIONS

There is sufficient evidence to recognize that walking is a useful therapeutic tool for people with T2DM. This document discusses theoretical and practical issues for improving its use. This article is co-published in the journals Sport Sciences for Health and Nutrition, Metabolism and Cardiovascular Diseases.

Current treatment for polycystic ovary syndrome: focus on adolescence

Polycystic ovary syndrome (PCOS) is the most frequent endocrine disorder in women and it is associated with an increased rate of infertility. Its etiology remains largely unknown, although both genetic and environmental factors play a role. PCOS is characterized by insulin resistance, metabolic disorders and low-grade chronic inflammation. To date, the treatment of PCOS is mainly symptomatic and aimed at reducing clinical signs of hyperandrogenism (hirsutism and acne), at improving menstrual cyclicity and at favoring ovulation. Since PCOS pathophysiology is still largely unknown, the therapeutic interventions currently in place are rarely cause-specific. In such cases, the therapy is mainly directed at improving hormonal and metabolic dysregulations typical of this condition. Diet and exercise represent the main environmental factors influencing PCOS. Thus, therapeutic lifestyle changes represent the first line of intervention, which, in combination with oral contraceptives, represent the customary treatment. Insulin resistance is becoming an increasingly studied target for therapy, most evidence stemming from the time-honored metformin use. Relatively novel strategies also include the use of thiazolidinediones and GLP1-receptor agonists. In recent years, a nutraceutical approach has been added to the therapeutic toolkit targeting insulin resistance. Indeed, emerging data support inositol and alpha-lipoic acid as alternative compounds, alone or in combination with the aforementioned strategies, with favorable effects on ovulation, insulin resistance and inflammation. Nevertheless, additional studies are required in adolescents, in order to assess the effectiveness of diet supplements in preventing negative impacts of PCOS on fertility in adult age. This review focuses on the main therapeutic options for PCOS to date.

Serum Androgens Are Independent Predictors of Insulin Clearance but Not of Insulin Secretion in Women With PCOS

CONTEXT/OBJECTIVE

In insulin-resistant individuals, hyperinsulinemia is a key compensatory mechanism, aimed at maintaining glucose homeostasis. Increased secretion and reduced clearance of insulin may both potentially contribute to this phenomenon. Insulin resistance and hyperinsulinemia are common findings in women with polycystic ovary syndrome (PCOS). While there is some information on insulin secretion, very few studies have investigated metabolic clearance rate of insulin (MCRI) in these women. Moreover, there is paucity of data on the relationships between MCRI and the pathophysiological characteristics of PCOS. The aim of the study was to explore these issues.

PATIENTS

One hundred ninety women with PCOS, diagnosed according to the Rotterdam criteria, with normal glucose tolerance.

DESIGN

Assessment of MCRI and clinical, hormonal, and metabolic characteristics of subjects. MCRI and insulin sensitivity were measured by the hyperinsulinemic euglycemic clamp. Serum androgens were assessed by liquid chromatography-mass spectrometry and equilibrium dialysis. A historical sample of healthy women was used to define the corresponding reference intervals.

RESULTS

MCRI was impaired in about two-thirds of women with PCOS. Subjects with low MCRI differed from those with normal MCRI for a number of anthropometric, metabolic, and endocrine features. In multivariate analysis, the degree of adiposity, estimates of insulin secretion, and serum androgen concentrations were independent predictors of MCRI. Conversely, age, adiposity, MCRI, and insulin sensitivity, but not serum androgens, were independent predictors of insulin secretion.

CONCLUSIONS

In women with PCOS, metabolic clearance of insulin is reduced, contributing to generating hyperinsulinemia. Serum androgens are independent predictors of this phenomenon.

Monitoring exercise intensity in diabetes: applicability of "heart rate-index" to estimate oxygen consumption during aerobic and resistance training

PURPOSE

Accurate quantification and monitoring of exercise "dose", described by oxygen consumption (VO₂), is necessary for exercise prescription and individualization. However, due to the complexity and elevated cost of direct, gold-standard methods, this is rarely done outside research laboratories. Heart rate-index (HR_index) is a new simple method to estimate VO₂ in healthy and clinical populations. We tested the performance of HR_index to estimate VO₂ in diabetic patients during aerobic (AT) and isotonic training (IT).

METHODS

Data from 12 males (age: 64 ± 5 years; BMI: 26 ± 12) with type 2 diabetes were analysed. VO₂ and heart rate were measured during one AT and one IT session. Furthermore, VO₂ was indirectly estimated based on HR_index. Then, the correspondence between measured and estimated VO₂ was evaluated by two-way RM-ANOVA, correlation and Bland-Altman analysis.

RESULTS

Estimated average VO₂ values during AT (1292 ± 366 ml/min) were not different from (p = 0.243) and highly correlated with (r = 0.87, p < 0.001) the measured values (1369 ± 417 ml/min), with a small bias and imprecision. Conversely during IT, HR_index overestimated VO₂ compared to the actual measures (1048 ± 404 vs 667 ± 230 ml/min, p ≤ 0.001) and only a moderate correlation was found between values (r = 0.43, p ≤ 0.001), with a large bias and imprecision.

CONCLUSION

VO₂ of aerobic exercises can be accurately estimated in diabetes patients using HR_index. During isotonic exercise, this method is not recommended for monitoring metabolic intensity due to large overestimation and imprecision. In aerobic exercise, HR_index offers a simple and valid alternative to the direct VO₂ determination and may favour the applicability of time-resolved measures of exercise "dose".

Effects of Aerobic and Resistance Training on Circulating Micro-RNA Expression Profile in Subjects With Type 2 Diabetes

CONTEXT

Structured exercise programs are of great benefit for the treatment of type 2 diabetes (T2DM). However, whether aerobic (AER) or resistance (RES) exercise training exerts specific epigenetic changes through the expression profile of circulating miRNAs (c-miRNAs) is still largely unknown.

OBJECTIVE

To assess whether the c-miRNAs profile changes after either AER or RES training in subjects with T2DM.

DESIGN

Twenty-four patients with T2DM randomized to AER or RES training protocols were randomly selected from the Resistance vs. Aerobic Exercise in Type 2 Diabetes (RAED2) Trial (NAER = 12; NRES = 12). The baseline and post-training levels of 179 c-miRNAs were initially measured by RT-PCR in 6 individuals (NAER = 3; NRES = 3). C-miRNAs exhibiting ≥40% fold change variation and/or nominal significance from baseline were measured in the whole group.

RESULTS

Nineteen c-miRNAs were eventually assessed in the whole group. Compared with baseline, the post-training levels of miR-423-3p, miR-451a, and miR-766-3p were significantly up-regulated, irrespective of exercise type (P < 0.0026; 0.05/19), and targeted upstream pathways relevant to fatty acids biosynthesis and metabolic regulation. MiR-451a and miR-423-3p were significantly correlated with fat loss (ρ = 0.45 and 0.43, respectively) and resulted, alone or in combination, in being predictors of fat loss in generalized linear regression models including exercise type as covariate. Only the association with miR-451a eventually retained significance after further correction for age, sex, body mass index, and HbA1c.

CONCLUSIONS

Exercise training in T2DM is associated with substantial c-miRNAs profile changes, irrespective of exercise type and other relevant metabolic covariates. The mechanistic significance of the observed relationship between fat loss and the epigenetic modifications induced by exercise warrants further investigation in larger datasets.

A Case Report of Insulinoma Relapse on Background Nesidioblastosis: A Rare Cause of Adult Hypoglycemia

CONTEXT

Nesidioblastosis is a rare cause of adult hypoglycemia. Current medical therapy can mitigate disease symptoms. However, side effects and limited efficacy may prevent long-term disease management.

CASE DESCRIPTION

A 63-year-old white woman presented at our institution on April 2017 with a history of distal spleno-pancreatectomy for well-differentiated insulinoma in 2013. Hypoglycemic events did not resolve after surgery, and residual nesidioblastosis near the pancreatic resection margins was identified. Hypoglycemic episodes increased in frequency and severity despite high-dose diazoxide (DZX) therapy. On April 2016, octreotide was introduced but soon discontinued for inefficacy. When the patient arrived at our attention, add-on pasireotide was started and glucose levels monitored by subcutaneous sensor. Compared with DZX, 225 mg/d alone, sensor glucose during pasireotide + DZX 75 mg/d showed occurrence of severe hypoglycemia. Pasireotide was discontinued, and the instrumental workup (68Ga-DOTATOC CT/positron emission tomography, 99mTc-nanocolloid scintigraphy and echo-endoscopy + fine-needle aspiration biopsy) identified an insulinoma relapse. Subtotal pancreatectomy was performed without further recurrence of hypoglycemia over 9 months of follow-up.

CONCLUSIONS

Although insulinoma relapses on background nesidioblastosis rarely occur, they should be considered as an alternate diagnosis when medical therapy fails to prevent hypoglycemia. Further studies are warranted to test whether the immunophenotypic signature of nesidioblastosis/insulinoma may provide insights for a tailored use of pasireotide.

Insulin resistance in a large cohort of women with polycystic ovary syndrome: a comparison between euglycaemic-hyperinsulinaemic clamp and surrogate indexes

STUDY QUESTION

Could surrogate indexes identify insulin resistant individuals among women with polycystic ovary syndrome (PCOS)?

SUMMARY ANSWER

Surrogate indexes may be able to rule in, but not rule out, insulin resistance in women with PCOS.

WHAT IS KNOWN ALREADY

Insulin resistance is a typical finding of women with PCOS and most clinical information on this issue is based upon surrogate indexes of insulin resistance. However, data on the performance of these indexes in PCOS women are very limited.

STUDY DESIGN SIZE, DURATION

A retrospective analysis of 406 women referred to our outpatient clinic for hyperandrogenism and/or menstrual dysfunction and submitted to hyperinsulinemic euglycaemic clamp between 1998 and 2015.

PARTICIPANTS/MATERIALS, SETTING, METHODS

In total, 375 of these women had PCOS by the Rotterdam criteria and were included in the study. Six surrogate indexes of insulin sensitivity were calculated from glucose and insulin levels, either at fasting (homeostasis model assessment (HOMA), glucose/insulin (G/I) ratio and quantitative insulin sensitivity check index (QUICKI)) or after oral glucose load (Gutt, Stumvoll0-120 and Matsuda).

MAIN RESULTS AND THE ROLE OF CHANCE

Overall, insulin resistance, as identified by the M-clamp value, was found in 74.9% of these women. The percentage was 59.3% in normal-weight vs 77.5% in overweight and 93.9% in obese subjects. All surrogate indexes were highly correlated with the M-clamp values. However, their ability to identify insulin resistant individuals was limited, in terms of sensitivity and especially in normal-weight subjects. ROC analysis showed similar performances of these indexes (AUC values 0.782-0.817).

LIMITATIONS REASONS FOR CAUTION

Potential referral bias of PCOS patients may have caused overestimation of the prevalence of insulin resistance in these women.

WIDER IMPLICATIONS OF THE FINDINGS

By using surrogate indexes many subjects with PCOS may be erroneously diagnosed as insulin sensitive, especially among normal-weight women. These indexes can be used to rule in, but not rule out, insulin resistance in PCOS.

STUDY FUNDING/COMPETING INTEREST(S)

Academic grants to P. Moghetti from the University of Verona. All authors declare no conflict of interest.

TRIAL REGISTRATION NUMBER

N/A.

Reassessing Free-Testosterone Calculation by Liquid Chromatography-Tandem Mass Spectrometry Direct Equilibrium Dialysis

CONTEXT

Assessment of free testosterone (FT) might help evaluate androgen status in patients with borderline total testosterone (T) and/or altered sex hormone-binding globulin (SHBG) levels. However, the validity of different methods to measure FT is debatable.

METHODS

Serum from 183 women and 146 men was analyzed using equilibrium dialysis (ED), with FT directly measured by liquid chromatography-tandem mass spectrometry. FT calculation was re-evaluated for the mass action law-based equation according to Vermeulen (cFT-V), empirical equations according to Ly (cFT-L), and a proposed calculation based on a multistep, dynamic, allosteric model according to Zakharov (cFT-Z).

RESULTS

FT level analyzed by ED [median,13 pmol/L (1.2% of T) in women; 248 pmol/L (1.5% of T) in men] was strongly inversely correlated to SHBG level, significantly to albumin level in women, and only weakly to SHBG level in men. The median [percentile (p) range, 2.5 to 97.5] ratios of calculated FT (cFT) over ED-FT (from European Male Aging Study samples) were 1.19 (0.9 to 1.47), 1.00 (0.69 to 1.42), and 2.05 (1.26 to 3.26) for cFT-V, cFT-L, and cFT-Z, respectively. The ratio for cFT-V was not significantly affected by SHBG, T, or albumin levels (ρ range, 0.17 to -0.01); ratios for cFT-L and cFT-Z were affected (P < 0.05 and P < 0.001, respectively) and strongly correlated with SHBG levels (ρ = 0.72 and 0.75, respectively). Rank correlations between cFT% and ED-FT% (for men) were 0.62, 0.74, and 0.89 for cFT-Z, cFT-L, and cFT-V, respectively.

CONCLUSION

FT results by direct ED confirm prior FT data from indirect ED and ultrafiltration methodologies. Calculations have inherent limitations, with clinically important differences among evaluated equations: cFT-V, although overestimating FT level, appears the most robust approximation, largely independent of SHBG, albumin, and T levels.

Sex differences in the association of psychological status with measures of physical activity and sedentary behaviour in adults with type 2 diabetes

AIM

To assess the association of psychological variables on leisure-time physical activity and sedentary time in men and women with type 2 diabetes mellitus (T2D).

METHODS

In this cross-sectional study, we evaluated 163 patients with T2D, consecutively recruited at the Diabetes Centre of the Verona General Hospital. Scores on depression and anxiety symptoms, psychosocial factors (including self-efficacy, perceived interference, perceived severity, social support, misguided support behaviour, spouse's positive behaviour), physical activity and time spent sitting were ascertained using questionnaires responses to the Beck Depression Inventory-II, Beck Anxiety Inventory, Multidimensional Diabetes Questionnaire, International Physical Activity Questionnaire.

RESULTS

Physical activity was significantly associated with higher social support in women and with increased self-efficacy in men. Sedentary time was significantly associated with higher perceived interference, anxiety and depressive symptoms, and with reduced diabetes self-efficacy in women, while it was associated solely with anxiety in men. Depressive symptoms and self-efficacy in women and anxiety symptoms in men were independent predictors of sedentary time when entered in a multivariable regression model also including age, BMI, haemoglobin A1c, diabetes duration, perceived interference and self-efficacy as covariates.

CONCLUSIONS

Lower self-efficacy and higher symptoms of depression were closely associated with increased sedentary time in women, but not in men, with T2D. It is possible that individualized behavioural interventions designed to reduce depressive symptoms and to improve diabetes self-efficacy would ultimately reduce sedentary behaviours, particularly in women with T2D.

The free androgen index is inaccurate in women when the SHBG concentration is low

OBJECTIVE/CONTEXT

The free androgen index (FAI) is known to give erroneous results in men, but it is still a commonly used test for the investigation of hyperandrogenism in women. This study aimed to compare the results of the FAI with the gold standard equilibrium dialysis method for free testosterone in women.

DESIGN/PATIENTS

Free serum testosterone T (ED-T) and total serum T (T) were measured by equilibrium dialysis and LC-MS/MS in patients with polycystic ovarian syndrome (n = 130), normal female controls (n = 53) and normal males (n = 120). Calculated free T (cFT) and free androgen index (FAI) were also measured in these patients. In addition, cFT was retrospectively calculated in 4223 female patients with a normal T (<1.6 nmol/L) routinely investigated for hyperandrogenism.

RESULTS

The cFT showed good agreement with measured ED-T, and the ratio cFT/ED-T was stable across all SHBG concentrations. In contrast, the FAI/ED-T ratio and the FAI/cFT ratio increased when the concentration of SHBG fell below 30 nmol/L.

CONCLUSIONS

The FAI is not a reliable indicator of free T when the SHBG concentration is low and would give misleading information in a large number of women being investigated for hyperandrogenism.

Association of free-living physical activity measures with metabolic phenotypes in type 2 diabetes at the time of diagnosis. The Verona Newly Diagnosed Type 2 Diabetes Study (VNDS)

BACKGROUND AND AIM

Lifestyle is considered a major determinant of risk of type 2 diabetes (T2D). We investigated whether daily physical activity (DPA) is associated with beta-cell function (BF) and/or insulin sensitivity (IS) in patients with T2D at the time of diagnosis.

METHODS AND RESULTS

In 41 subjects enrolled in the Verona Newly-Diagnosed Type 2 Diabetes Study we assessed: (1) IS, by euglycaemic insulin clamp; (2) BF, estimated by prolonged-OGTT minimal modeling and expressed as derivative and proportional control; (3) DPA and energy expenditure (EE), assessed over 48-h monitoring by a validated wearable armband system. Study participants (median [IQR]; age: 62 [53-67] years, BMI: 30.8 [26.5-34.3] Kg m^-2, HbA1c: 6.7 [6.3-7.3]%; 49.7 [45.4-56.3] mmol/mol) were moderately active (footsteps/day: 7773 [5748-10,927]; DPA_≥3MET: 70 [38-125] min/day), but none of them exercised above 6 metabolic equivalents (MET). EE, expressed as EE_TOT (total daily-EE) and EE_≥3MET (EE due to DPA_≥3MET) were 2398 [2226-2801] and 364 [238-617] Kcal/day, respectively. IS (M-clamp 630 [371-878] μmol/min/m²) was positively associated with DPA and EE, independent of age, sex and BMI (p < 0.05). Among the DPA and EE parameters assessed, DPA_≥3MET and EE_TOT were independent predictors of IS in multivariable regression analyses, adjusted for age, sex, BMI (R² = 16%, R² = 19%, respectively; p < 0.01). None of model-derived components of BF was significantly associated with DPA or accompanying EE.

CONCLUSIONS

Our study highlighted moderate levels of DPA and total EE as potential determinants of IS, but not BF, in T2D at the time of diagnosis. Intervention studies are needed to conclusively elucidate the effect of DPA on these features.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov.

UNIQUE IDENTIFIER

NCT01526720.

Effects of aerobic or resistance exercise training on cardiovascular autonomic function of subjects with type 2 diabetes: A pilot study

BACKGROUND AND AIMS

Both aerobic (AER) and resistance (RES) training improve metabolic control in patients with type 2 diabetes (T2DM). However, information on the effects of these training modalities on cardiovascular autonomic control is limited. Our aim was to compare the effects of AER and RES training on cardiovascular autonomic function in these subjects.

METHODS AND RESULTS

Cardiovascular autonomic control was assessed by Power Spectral Analysis (PSA) of Heart Rate Variability (HRV) and baroreceptors function indexes in 30 subjects with T2DM, randomly assigned to aerobic or resistance training for 4 months. In particular, PSA of HRV measured the Low Frequency (LF) and High Frequency (HF) bands of RR variations, expression of prevalent sympathetic and parasympathetic drive, respectively. Furthermore, we measured the correlation occurring between systolic blood pressure and heart rate during a standardized Valsalva maneuver using two indexes, b2 and b4, considered an expression of baroreceptor sensitivity and peripheral vasoactive adaptations during predominant sympathetic and parasympathetic drive, respectively. After training, the LF/HF ratio, which summarizes the sympatho-vagal balance in HRV control, was similarly decreased in the AER and RES groups. After AER, b2 and b4 significantly improved. After RES, changes of b2 were of borderline significance, whereas changes of b4 did not reach statistical significance. However, comparison of changes in baroreceptor sensitivity indexes between groups did not show statistically significant differences.

CONCLUSION

Both aerobic and resistance training improve several indices of the autonomic control of the cardiovascular system in patients with T2DM. Although these improvements seem to occur to a similar extent in both training modalities, some differences cannot be ruled out.

CLINICAL TRIAL REGISTRATION NUMBER

NCT01182948, clinicaltrials.gov.

Comparison between dual-energy X-ray absorptiometry and skinfold thickness in assessing body fat in overweigh/obese adult patients with type-2 diabetes

Percentage of body fat (%BF) is estimated in clinical practice using anthropometric equations, but little is known about their reliability in overweight/obese patients with type-2 diabetes. The aim of this study was to compare, in overweight/obese adults with type-2 diabetes, %BF estimated with several commonly used anthropometric equations and %BF measured with dual-energy X-ray absorptiometry (DXA, Hologic). The %BF was measured with DXA in 40 patients aged 40-68 years with type-2 diabetes (mean HbA1c, 7.3 ± 0.9%). Body density was estimated in the same patients by means of four anthropometric equations and converted to %BF using the Siri and Brozek equations. Paired-sample t-test and the mean signed difference procedure were used to compare anthropometric equation-derived %BF and DXA measurements. The coefficient of determination was computed. Bland-Altman analysis was used to test the agreement between methods. Among the four anthropometric equations, the Durnin-Womersley equation only showed close agreement with DXA in both female and male patients; the other equations significantly underestimated or overestimated %BF. Two new predictive equations were developed using DXA as the reference to predict total body and trunk %BF. Further comparative studies are required to confirm and refine the accuracy of practical, non-invasive methods for monitoring %BF in this population.

Insulin Resistance and Polycystic Ovary Syndrome

BACKGROUND

Insulin resistance and the associated compensatory hyperinsulinemia are common findings in women with PCOS, and may play a key role in this condition.

METHODS

In this article, we focused on the significance of insulin resistance in PCOS, reviewing the available literature on epidemiology, pathogenesis, pathophysiology and treatment of this condition.

RESULTS

It has been estimated that approximately 70% of these women are insulin resistant, but this figure is affected by frequent referral bias. In addition, there is metabolic heterogeneity between clinical phenotypes of PCOS. A fundamental issue is the role that hyperinsulinemia plays in androgen overproduction, which is enhanced by bidirectional links between insulin resistance and hyperandrogenism. Available data suggest that women with PCOS may have insulin action alterations of heterogeneous origins, which induce specific abnormalities in these subjects due to the presence of intrinsic defects. Obesity is a common finding in these patients and contributes to the association between PCOS and insulin resistance, combining with the effect of PCOS per se. Insulin sensitization shows several beneficial effects in the treatment of this condition. However, clinical response is heterogeneous.

CONCLUSION

Insulin resistance is a common feature of women with PCOS, although it is not universal and differ between clinical phenotypes of PCOS. Insulin resistance and hyperandrogenism appear to be interrelated key factors in the pathogenesis of PCOS. We hypothesize that PCOS might represent a common end-stage clinical phenotype of different processes, in which there are impaired insulin action and hyperandrogenism, probably favoured by specific, intrinsic abnormalities of these women.

Is cardiorespiratory fitness impaired in PCOS women? A review of the literature

PURPOSE

Polycystic ovary syndrome (PCOS) is a common and heterogeneous endocrine disorder, affecting 8-12% of reproductive-aged women. Insulin resistance and body fat excess are common features in these subjects. Increased physical activity and diet modifications are the first recommended approach in the management of these women, at least in overweight/obese subjects. Evaluation of cardiorespiratory fitness (CRF) is important in assessing exercise performance and in monitoring the effects of physical exercise interventions. Several studies have shown that CRF may be impaired in metabolic and endocrine disorders. However, there are little data on this issue in PCOS women. The aim of this narrative review is to critically evaluate whether aerobic capacity is altered in PCOS women, focusing on maximal oxygen uptake.

METHODS

An updated search of the literature was performed, identifying papers with maximal oxygen consumption measurements in women with PCOS compared to healthy controls.

RESULTS

We have identified six studies on this specific topic: four of them showed an alteration of maximal oxygen consumption in PCOS women, whereas two did not. However, taken together these studies suggest that CRF may be strikingly impaired in both normal-weight and overweight/obese subjects with this condition.

CONCLUSIONS

Women with PCOS appear to be characterized by a reduced cardiopulmonary fitness. However, further research on this topic is needed. This information may hopefully help clinicians and exercise specialist in planning individualized exercise programs aimed at improving the metabolic and endocrine outcomes in these women.

Metabolic Effects of Exercise

Exercise has a powerful action on metabolism, and adaptation of the body to changes induced by exercise is fundamental to be able to provide the energy required for muscle contraction and physiological functions of vital tissues. Depending on the intensity and duration of exercise, different mechanisms are called on to make energy available, and under homeostatic control, this is guaranteed by rapid and coordinated changes in the secretion of several hormones. Molecular mechanisms controlling muscle function and fiber phenotype are related to the specific mode of muscle activation. We can distinguish between two fundamental types of physical activity, endurance exercise and strength exercise, although there is a continuum between these exercise modalities. Besides the acute changes induced by a single exercise session, regular exercise may induce chronic adaptations, improving exercise capacity and affecting energy metabolism. Notably, although acute metabolic effects of exercise are mostly due to insulin-independent effects, exercise training may improve muscle insulin sensitivity and is considered a key tool in the prevention and treatment of metabolic disorders. This chapter focuses on the biochemistry of energy supply to the exercising muscle, on molecular mechanisms involved and on the physiology of energy metabolism during exercise in healthy subjects and patients with insulin resistance and/or diabetes.

Implications of Androgen Assay Accuracy in the Phenotyping of Women With Polycystic Ovary Syndrome

CONTEXT/OBJECTIVE

Hyperandrogenism is a common feature of women with polycystic ovary syndrome (PCOS) and is considered a cardinal element for the diagnosis and phenotyping of this condition. Unfortunately, routinely available methods for measuring serum androgens suffer from major limitations. No data are available on the impact of androgen assay quality on the assignment of PCOS women to the different clinical phenotypes of PCOS, when defined according to the Rotterdam criteria for diagnosis.

PATIENTS

Two hundred four consecutive Caucasian women with PCOS, diagnosed by the Rotterdam criteria participated in the study.

DESIGN

Assessment of total T (TT), free T (FT), and androstenedione (A) by both a chemiluminescent assay, routinely available in our hospital, and gold standard methodology, ie, liquid chromatography-mass spectrometry and equilibrium dialysis, was performed. The results were compared and the associations of these data with clinical and metabolic features of PCOS women were analyzed.

RESULTS

By using gold standard assays, TT was high in 36.3% of women, whereas A only marginally contributed to identifying hyperandrogenemic patients. However, gold standard FT measurement was elevated in 70.6% of the PCOS patients, identifying them as hyperandrogenemic. Routine TT and A assays, and the derived calculated FT, were strikingly inaccurate, with substantial overestimation. These assays erroneously classified 60 patients (29.4%), 32 as false hyperandrogenemic, and 28 as false normoandrogenemic, with incorrect assignment of many patients to the clinical phenotypes of PCOS and inappropriate estimation of their metabolic risk. In particular, women misclassified as normoandrogenic had a more severe metabolic profile than true normoandrogenic subjects.

CONCLUSIONS

FT alone, as measured by equilibrium dialysis or calculated by using the Vermeulen formula, provided that TT is assayed by gold standard methodology, can be used to identify hyperandrogenemic PCOS subjects. The use of routine androgen assays may misclassify the phenotype of many PCOS women, with errors in the estimation of individual metabolic risk.

Serum testosterone predicts cardiorespiratory fitness impairment in normal-weight women with polycystic ovary syndrome

OBJECTIVE

Limited literature has shown that maximal oxygen consumption (V'O2max), that is the maximal capacity of an individual to perform aerobic work, may be lowered in overweight/obese women with polycystic ovary syndrome (PCOS). However, it remains unclear whether this impairment is associated with PCOS per se or is entirely due to body fat excess. Our objective was to assess whether cardiorespiratory fitness is altered in normal-weight PCOS women and to investigate which factors are associated with this phenomenon.

SUBJECTS

Fifteen normal-weight PCOS women and 15 age- and BMI-matched healthy controls. Fourteen subjects in each group completed the protocol.

MEASUREMENTS

V'O2max and ventilatory thresholds (maximal incremental cycle ergometer test with breath-by-breath analysis of gas exchange), insulin sensitivity (hyperinsulinaemic euglycaemic clamp) and androgenaemia (serum total and free testosterone, measured by liquid chromatography mass spectrometry and equilibrium dialysis) were accurately assessed.

RESULTS

Maximal V'O2 and power were strikingly impaired in normal-weight PCOS individuals, as compared with healthy controls (29·4 ± 1·5 vs 35·8 ± 1·6 ml O2/kg/min, P = 0·008; 138 ± 6 vs 170 ± 10 W, P = 0·011, respectively). Similarly, oxygen consumption and power at both the first and second ventilatory thresholds were significantly lower in PCOS subjects than in healthy women. In multiple regression analysis, V'O2max was negatively predicted by serum-free testosterone levels, but not by body fat mass and glucose disposal rate (R(2) = 0·45 P = 0·013).

CONCLUSIONS

Cardiorespiratory fitness is impaired in normal-weight PCOS women. Androgen excess but not insulin sensitivity is associated with this alteration.

Diabetic pregnancy outcomes in mothers treated with basal insulin lispro protamine suspension or NPH insulin: a multicenter retrospective Italian study

OBJECTIVE

The aim of this study was to study the efficacy and safety of long-acting insulin analog insulin lispro protamine suspension (ILPS) in diabetic pregnant women.

METHODS

In a multicenter observational retrospective study, we evaluated pregnancy outcome in 119 women affected by type 1 diabetes and 814 with gestational diabetes (GDM) treated during pregnancy with ILPS, compared with a control group treated with neutral protamine hagedorn (NPH) insulin.

RESULTS

Among type 1 diabetic patients, fasting blood glucose at the end of pregnancy was significantly lower in ILPS-treated than in NPH-treated patients. HbA1c levels across pregnancy did not differ between groups. Caesarean section and preterm delivery rates were significantly lower in the ILPS-women. Fetal outcomes were similar in the ILPS and NPH groups. Among GDM women, fasting blood glucose at the end of pregnancy was significantly lower in ILPS-treated than in NPH-treated patients. Duration of gestation was significantly longer, caesarian section and preterm delivery rates were lower in the ILPS-treated group. In addition, there were significantly fewer babies with an excessive ponderal index or neonatal hypoglycemic episodes in the ILPS group than in the NPH group.

CONCLUSIONS

Association of ILPS with rapid-acting analogs in pregnancy is safe in terms of maternal and fetal outcomes.

Total body fat and central fat mass independently predict insulin resistance but not hyperandrogenemia in women with polycystic ovary syndrome

CONTEXT/OBJECTIVE

Obesity is a common feature of women with polycystic ovary syndrome (PCOS). The aim of this study was to assess the role of body fat on insulin resistance and androgen excess in these subjects.

PATIENTS/DESIGN

One hundred sixteen consecutive Caucasian women with PCOS, diagnosed by the Rotterdam criteria, underwent accurate assessment of clinical, anthropometric, hormonal, and metabolic features. In particular, total fat mass and fat distribution were assessed by dual-energy x-ray absorptiometry, serum-free T by liquid chromatography mass spectrometry and equilibrium dialysis and insulin sensitivity by the glucose clamp technique.

RESULTS

Total fat mass and truncal fat were significantly higher in insulin-resistant than in insulin-sensitive PCOS subjects (+89% and +127%, respectively, both P < .001), and both tended to be higher in hyperandrogenemic than in normoandrogenemic women (+22% and +28%, respectively, P = .087 and P = .090). All parameters of adiposity correlated inversely with insulin sensitivity (P < .001) and directly with serum-free T (P ≤ .001). A statistically significant inverse relationship was observed between insulin sensitivity and serum-free T concentrations (r = -0.527, P < .001). In a multiple regression analysis, either total fat mass or truncal fat, in addition to serum-free T and age, were independent predictors of insulin sensitivity. However, insulin sensitivity, but not total fat mass or truncal fat, was an independent predictor of free T concentrations.

CONCLUSIONS

These data suggest that body fat contributes to determining insulin resistance in PCOS women. However, the association between body fat and hyperandrogenism seems to be to a large extent explained by insulin resistance.

Hemostatic and fibrinolytic abnormalities in polycystic ovary syndrome

Polycystic ovary syndrome (PCOS) is the most common form of anovulatory infertility, affecting up to 10% of women of reproductive age. This syndrome was first described in 1935 when American gynecologists Stein and Leventhal associated the presence of ovarian cysts with anovulation, obesity, and hirsutism. For many years, the effects of PCOS on coagulation and fibrinolysis have remained largely unexplored. This review summarizes current knowledge of the effects of PCOS on coagulation and fibrinolysis, and the putative mechanisms by which PCOS may contribute to the development of coagulation and fibrinolytic disorders. To date, there is relatively strong evidence suggesting that PCOS is associated with increased platelet aggregation and decreased plasma fibrinolytic activity. However, whether these hemostatic disorders are linked to the abnormal hormonal system in PCOS remains to be elucidated. Moreover, it should be emphasized that PCOS is a heterogeneous endocrine condition, and that the number of published studies is limited, the sample size of most of these studies is relatively small, and the selection of control subjects has not been always appropriate. Furthermore, well-designed studies on larger cohorts of carefully characterized PCOS patients are needed to provide more comprehensive information on this issue.

Plasma levels of pentraxin-3, an inflammatory protein involved in fertility, are reduced in women with polycystic ovary syndrome

OBJECTIVE

Pentraxin-3 (PTX3), like C-reactive protein (CRP), is an acute-phase protein that belongs to the pentraxin superfamily. Moreover, it is expressed in the cumulus oophorus and appears to be involved in female fertility. The aim of the present study was to assess whether PTX3 levels are altered in polycystic ovary syndrome (PCOS) women and whether they show any relationship with the main features of these subjects.

DESIGN

A cross-sectional study was conducted at the outpatient clinic of an academic centre.

METHODS

A total of 66 women affected with PCOS and 51 healthy controls were studied. Plasma PTX3 and serum CRP were measured by ELISA. Androgens were measured by liquid chromatography-mass spectrometry and free testosterone was measured by equilibrium dialysis. In PCOS women, insulin sensitivity was assessed by the glucose clamp technique.

RESULTS

Adjusting for age and BMI, plasma PTX3 was reduced in PCOS women (P=0.036), in contrast with serum CRP, which was increased (P=0.004). In multiple regression analysis, serum androgens and other endocrine and ovarian features of PCOS were predictors of PTX3 levels, whereas body fat was the main independent predictor of CRP concentrations.

CONCLUSIONS

Plasma PTX3 levels were reduced in PCOS women and independently associated with hyperandrogenism and other endocrine and ovarian features of PCOS.

Relationships between cardiorespiratory fitness, metabolic control, and fat distribution in type 2 diabetes subjects

Factors contributing to the reduced cardiorespiratory fitness typical of sedentary subjects with type 2 diabetes are still largely unknown. In this study, we assessed the relationships between cardiorespiratory fitness and abdominal and skeletal muscle fat content in 39 untrained type 2 diabetes subjects, 27 males and 12 females (mean ± SD age 56.5 ± 7.3 year, BMI 29.4 ± 4.7 kg/m(2)). Peak oxygen uptake (VO2peak) and ventilatory threshold (VO2VT) were assessed by maximal cycle ergometer exercise test, insulin sensitivity by euglycemic-hyperinsulinemic clamp, and body composition by dual-energy X-ray absorptiometry. Magnetic resonance imaging was used to evaluate visceral, total subcutaneous (SAT), superficial (SSAT) and deep sub-depots of subcutaneous abdominal adipose tissue, and sagittal abdominal diameter (SAD), as well as femoral quadriceps skeletal muscle fat content. In univariate analysis, both VO2peak and VO2VT were inversely associated with BMI, total fat mass, SAT, SSAT, and sagittal abdominal diameter. VO2peak was also inversely associated with skeletal muscle fat content. A significant direct association was observed between VO2VT and insulin sensitivity. No associations between cardiorespiratory fitness parameters and metabolic profile data were found. In multivariable regression analysis, after adjusting for age and gender, VO2peak was independently predicted by higher HDL cholesterol, and lower SAD and skeletal muscle fat content (R (2) = 0.64, p < 0.001), whereas VO2VT was predicted only by sagittal abdominal diameter (R (2) = 0.48, p = 0.025). In conclusion, in untrained type 2 diabetes subjects, peak oxygen uptake is associated with sagittal abdominal diameter, skeletal muscle fat content, and HDL cholesterol levels. Future research should target these features in prospective intervention studies.

Both resistance training and aerobic training reduce hepatic fat content in type 2 diabetic subjects with nonalcoholic fatty liver disease (the RAED2 Randomized Trial)

Although lifestyle interventions are considered the first-line therapy for nonalcoholic fatty liver disease (NAFLD), which is extremely common in people with type 2 diabetes, no intervention studies have compared the effects of aerobic (AER) or resistance (RES) training on hepatic fat content in type 2 diabetic subjects with NAFLD. In this randomized controlled trial, we compared the 4-month effects of either AER or RES training on insulin sensitivity (by hyperinsulinemic euglycemic clamp), body composition (by dual-energy X-ray absorptiometry), as well as hepatic fat content and visceral (VAT), superficial (SSAT), and deep (DSAT) subcutaneous abdominal adipose tissue (all quantified by an in-opposed-phase magnetic resonance imaging technique) in 31 sedentary adults with type 2 diabetes and NAFLD. After training, hepatic fat content was markedly reduced (P < 0.001), to a similar extent, in both the AER and the RES training groups (mean relative reduction from baseline [95% confidence interval] -32.8% [-58.20 to -7.52] versus -25.9% [-50.92 to -0.94], respectively). Additionally, hepatic steatosis (defined as hepatic fat content >5.56%) disappeared in about one-quarter of the patients in each intervention group (23.1% in the AER group and 23.5% in the RES group). Insulin sensitivity during euglycemic clamp was increased, whereas total body fat mass, VAT, SSAT, and hemoglobin A1c were reduced comparably in both intervention groups.

CONCLUSION

This is the first randomized controlled study to demonstrate that resistance training and aerobic training are equally effective in reducing hepatic fat content among type 2 diabetic patients with NAFLD.

Metabolic inflexibility is a feature of women with polycystic ovary syndrome and is associated with both insulin resistance and hyperandrogenism

CONTEXT

Metabolic inflexibility, ie, the impaired ability of the body to switch from fat to carbohydrate oxidation under insulin-stimulated conditions, is associated with insulin resistance. This alteration in metabolic plasticity can lead to organ dysfunction and is considered a key issue among the abnormalities of the metabolic syndrome. It is still unknown whether this phenomenon occurs in women with polycystic ovary syndrome (PCOS).

OBJECTIVE

Our objective was to examine whether metabolic inflexibility is a feature of PCOS women and whether hyperandrogenism may contribute to this phenomenon.

DESIGN AND PATIENTS

Eighty-nine Caucasian women with PCOS were submitted to hyperinsulinemic-euglycemic clamp. Respiratory exchange ratios were evaluated at baseline and during hyperinsulinemia by indirect calorimetry to quantify substrate oxidative metabolism. Total testosterone was measured by liquid chromatography mass spectrometry and free testosterone by equilibrium dialysis.

SETTING

Outpatients were seen in a tertiary care academic center.

MAIN OUTCOME MEASURE

Metabolic flexibility was assessed by the change in respiratory quotient upon insulin stimulation.

RESULTS

Sixty-five of the 89 PCOS women (73%) had increased serum free testosterone, 68 (76%) were insulin resistant, and 62 (70%) had an impaired metabolic flexibility. Comparison of hyperandrogenemic and normoandrogenemic women showed that the 2 subgroups were of similar age but differed in terms of several anthropometric and metabolic features. In particular, hyperandrogenemic women had greater body mass index (32.9 ± 1.0 vs 24.7 ± 0.9 kg/m(2), P < .001) and lower glucose utilization during the clamp (9.2 ± 0.4 vs 10.9 ± 0.7 mg/kg fat-free mass · min, P = .023) and metabolic flexibility (0.09 ± 0.06 vs 0.12 ± 0.01, P = .014). In univariate analysis, metabolic flexibility was associated with several anthropometric, endocrine, and metabolic features. In multivariate analysis, this feature was directly associated with baseline respiratory quotient and insulin sensitivity and inversely with free testosterone and free fatty acids concentrations under insulin suppression (R(2) = 0.634, P < .001).

CONCLUSIONS

Metabolic inflexibility is a feature of PCOS women. Both insulin resistance and androgen excess might contribute to this abnormality.

Low body weight and menstrual dysfunction are common findings in both elite and amateur ballet dancers

BACKGROUND

Several studies have reported that low body weight and menstrual alterations are very frequent findings in elite dancers, suggesting they could be at risk for associated medical problems. However, it is still largely unknown whether these alterations are also common in the very large number of young amateur dancers.

AIM

The aim of this study was to assess whether there is an increased prevalence of menstrual dysfunction also in amateur dancers.

MATERIAL/SUBJECTS AND METHODS

Ninety-two professional ballet dancers, 93 non-professional ballet dancers, and 293 (160 sedentary, 133 physically active) control women, ranging in age 14-23 yr, were included in the study. In these subjects, a detailed questionnaire that included questions on weight, height, age at menarche, training profile and menstrual alterations was administered.

RESULTS

BMI was lower in both professional and non-professional dancers than in controls. Frequency of menstrual dysfunction was 51%, 34% and 21% in professional dancers, non-professional dancers and controls, respectively (p<0.0001). Amenorrhea was reported by 23% of professional dancers, vs 1-7% in the other groups (p<0.0001). Age at menarche occurred later in professional dancers than in the other groups. Logistic regression analyses showed that menstrual dysfunction was associated with the training profile in professional dancers, and with BMI in non-professional dancers. Age at menarche was associated with menstrual dysfunction in both groups.

CONCLUSIONS

This study shows that low body weight and menstrual dysfunction are frequent findings also in amateur ballet dancers.