Circulating E-selectin levels and insulin resistance are associated with early stages of atherosclerosis in nonfunctional adrenal incidentaloma

Relationship of obesity, body fat, benign adrenal tumors and the mediating mechanism: a two-step mendelian randomization study

BACKGROUND

Benign adrenal tumors comprise the majority of asymptomatic adrenal masses and are often associated with cortisol secretion, which increases the risk of obesity and metabolic syndrome. Hormone secretion by these tumors may confound prevailing epidemiologic findings, and the causal relationships among obesity, body fat, and benign adrenal tumors remain uncertain. Mendelian randomization (MR) uses genetic variation as an instrumental variable to simulate randomized controlled trials, thereby reducing confounding and supporting causal relationships. Therefore, we aim to use MR methods to investigate causal relationships between obesity, body fat, and benign adrenal tumors. And use two-step MR to evaluate potential mediating mechanisms and their mediation proportions.

METHOD

Single nucleotide polymorphisms significantly associated with obesity, body fat and possible mediators were selected as instrumental variables from published genome-wide association studies (GWAS). GWAS data for benign adrenal tumor cases (n = 1,790) and controls (n = 390,633) were obtained from the Finngen database. Univariable MR analysis was performed to evaluate the causal associations of obesity and body fat with benign adrenal tumors, with obesity and body fat quantified using ten anthropometric indicators. In addition, two-step MR was used to examine four categories of possible mediators (metabolic indicators, hormone indicators, inflammation and oxidation indicators, and diseases) to explore potential mechanisms between obesity, body fat, and benign adrenal tumors and to calculate mediation proportions.

RESULT

Our results show that all anthropometric indicators are risk factors for benign adrenal tumors (OR range from 1.59 to 2.49 with FDR < 0.05). In addition, two-step MR analysis shows that both total and bioavailable testosterone levels significantly mediate body fat percentage, trunk fat percentage, and trunk fat mass on benign adrenal tumors in women (mediation proportion: 4.07%-15.58%). In addition, bioavailable testosterone levels mediate whole body fat mass (10.95%) and body mass index (17.04%), while total testosterone levels mediate hip circumference (7.27%) in women.

CONCLUSION

Our study demonstrates that obesity and elevated body fat may serve as risk factors for benign adrenal tumors. Furthermore, we identify the mediating role of total/bioavailable testosterone levels in women, suggesting its potential target for prevention and intervention of benign adrenal tumors in individuals with obesity or high body fat.

Cardiometabolic comorbidities and cardiovascular events in "non-functioning" adrenal incidentalomas: a systematic review and meta-analysis

OBJECTIVE

Recent studies investigated the prevalence of arterial hypertension (AH), diabetes mellitus (DM) and/or prediabetes, dyslipidemia (DL), metabolic syndrome (MS) and cardiovascular events (CVE) in patients with non-functioning adrenal incidentalomas (NFAI). We aimed to investigate the available literature to determine the prevalence of AH, DM, DM and/or prediabetes (Composite DM, C-DM), DL, MS and CVE in patients with NFAI as compared to patients without adrenal incidentalomas (AI).

DESIGN

Systematic review and meta-analysis.

METHODS

A meta-analysis was performed using studies that evaluated the prevalence of AH, DM, C-DM, DL, MS and CVE in patients with NFAI versus matched subjects without AI. A random-effects model (DerSimonian and Laird) was used to calculate the pooled odds ratio (OR) and 95% Confidence Interval (95%CI) for each outcome.

RESULTS

Among the 36 available studies, 19 studies provided the necessary data (4716 subjects, mean age 57.6 ± 4.6). The association between AH, DM, C-DM, DL, MS and CVE was reported in 18 (4546 subjects), 7 (1743 subjects), 5 (4315 subjects), 11 (3820 subjects), 8 (1170 subjects) and 5 (2972 subjects), respectively. The presence of NFAI was associated with AH (OR 1.87, 95%CI 1.39-2.51), C-DM (OR 2.04, 95%CI 1.70-2.45) and MS (OR 2.89, 95%CI 1.93-4.32), but not with DM, DL and CVE.

CONCLUSIONS

Patients with NFAI have higher prevalence of AH, C-DM and MS than control subjects without NFAI.

Cross-sectional, interventional, and causal investigation of insulin sensitivity using plasma proteomics in diverse populations

Background

We previously reported significant correlations between a direct measure of insulin sensitivity (IS) and blood levels of proteins measured using the Proximity Extension Assay (PEA) in two European cohorts. However, protein correlations with IS within non-European populations, in response to short-term interventions that improve IS, and any causal associations with IS have not yet been established.

Methods

We measured 1,470 proteins using the PEA in the plasma of 1,015 research participants at Stanford University who underwent one or more direct measures of IS. Association analyses were carried out with multivariable linear regression within and across Stanford subgroups and within each of the two European cohorts. Association statistics were also meta-analyzed after transformation and harmonization of the two direct measures of IS. Lastly, we performed genome-wide association studies of IS and used genetic instruments of plasma proteins from the UK Biobank to identify candidate causal proteins for IS through Mendelian Randomization (MR) analysis.

Results

In age and sex adjusted model, 810 proteins were associated with baseline IS among 652 self-reported European participants in the Stanford cohort at a false discovery rate (FDR) < 0.05. Effect sizes for these proteins were highly correlated with those observed in 122 South Asian, 92 East Asian, 85 Hispanic, and 52 Black/African American persons (r= 0.68 to 0.83, all P≤4.3×10-113). Meta-analysis of the full Stanford cohort with the two European cohorts (N=2,945) yielded 247 significant protein associations (FDR < 0.05), with 75 remaining significant after further adjustment for body mass index. In a subset of Stanford participants undergoing insulin sensitizing interventions (N=53 taking thiazolidinediones, N=66 with weight loss), 79.6% of protein level changes were directionally consistent with the respective baseline association (observed/expected p=6.7×10-16). MR analyses identified eight candidate causal proteins for IS, among which were SELE and ASGR1, proteins with established drug targets currently under investigation.

Conclusion

Plasma proteins measured using the PEA provide a robust signature for IS across diverse populations and after short-term insulin sensitizing interventions highlighting their potential value as universal biomarkers of insulin resistance. A small subset of markers provided insights into potential causal molecular mechanisms and therapeutic targets.

Increased cardiometabolic risk and prevalence of ascending aorta dilation in patients with nonfunctioning adrenal incidentaloma: a retrospective propensity score-matched study

The cardiometabolic implications of Non-Functioning Adrenal Incidentaloma (NFAI) is still matter of debate. This study takes a novel approach to analyze this association, accounting for the influence of various confounding factors. We present the findings of a retrospective, cross-sectional, and case-control study. Data from all NFAI patients in primary prevention, referred to the University of Turin between 2000 and 2023, were collected and compared with subjects without adrenal disease, using propensity score matching analysis. A total of 1997 patients were included (906 patients with NFAI; 1091 controls). Adrenal tumor group was associated with high levels of cardiovascular risk scores in both univariate and multiple linear regression analyses (Progetto CUORE: EC 11.00, 95% CI 2.72-44.46, p = 0.001; SCORE: EC 1.97, 95% CI 1.01-3.81, p = 0.046). Regarding cardiometabolic complications, multivariable logistic regression revealed an independent association between NFAI and ascending aorta dilation (OR 4.64, 95% CI 2.24-9.63, p = 0.000), after adjusting for age, sex, smoking status, metabolic syndrome, number of antihypertensive drugs, estimated glomerular filtration rate (eGFR), and normetanephrine levels. Propensity score matching analysis (1:1 matching ratio), based on the same logistic regression model, confirmed the association of NFAI with aortic dilation (β = 0.083, 95% CI 0.008-0.157, p = 0.030). No significant associations were found with metabolic syndrome, type II diabetes, eGFR <60 mL/min/1.73 m2, microalbuminuria, atrial fibrillation, or hypertensive heart disease. This study suggests that patients with NFAI face increased cardiometabolic risk and high prevalence of ascending aorta dilation. Routine evaluation of NFAI patients should include thorough cardiovascular assessment and consideration of treatments aimed at reducing cardiovascular risk.

A retrospective study on the association between urine metanephrines and cardiometabolic risk in patients with nonfunctioning adrenal incidentaloma

Several studies argued that cardiovascular evaluation of patients with nonfunctioning adrenal incidentaloma is of particular importance. Therefore, we aimed to evaluate the possibility of stratifying the cardiometabolic risk using metanephrine levels in this setting of patients. A retrospective cross-sectional study was designed, collecting data of metanephrine values in 828 patients with nonfunctioning adrenal incidentaloma, referred to our Division within the University of Turin between 2007 and 2021. The univariate analysis showed associations between urine metanephrines and cardiometabolic variables/parameters, particularly considering the noradrenaline metabolite. At the univariate regression, normetanephrine was associated with metabolic syndrome (OR = 1.13, p = 0.002), hypertensive cardiomyopathy (OR = 1.09, p = 0.026), microalbuminuria (OR = 1.14, p = 0.024), and eGFR < 60 mL/min/1.73 m2 (OR = 1.11, p = 0.013), while metanephrine was associated with microalbuminuria (OR = 1.50, p = 0.008). At multivariate regression, considering all major cardiovascular risk factors as possible confounders, normetanephrine retained a significant association with metabolic syndrome (OR = 1.10, p = 0.037). Moreover, metanephrine retained a significant association with the presence of microalbuminuria (OR = 1.66, p = 0.003). The present study showed a further role for metanephrines in the cardiovascular risk stratification of patients with nonfunctioning adrenal incidentaloma. Individuals with high levels of these indirect markers of sympathetic activity should be carefully monitored and may benefit from an aggressive treatment to reduce their additional cardiometabolic burden.

Is Apelin a new biomarker in patients with polycystic ovary syndrome?

Polycystic ovary syndrome (PCOS) is associated with multiple risk factors for cardiovascular diseases, including insulin resistance, diabetes mellitus type 2, obesity, hypertension, and dyslipidaemia. Many studies have assessed the role of adipokines in the etiopathogenesis of PCOS, however, no single biomarker has been recognized to be in causal relation to the syndrome. Apelin has been identified as a new adipokine linked to obesity and insulin resistance. Some studies demonstrated that the apelin / apelin receptor could play a pivotal role in the pathogenesis of polycystic ovary syndrome, however the other yielded controversial results. Underlying mechanisms of possible involvement of apelin/apelin receptor complex are discussed.

Nonfunctional adrenal adenomas and impaired glucose metabolism: a systematic review and meta-analysis

PURPOSE

Evidence on nonfunctioning adrenal incidentaloma's (NFAI) associated comorbidities and in particular, glucose disorders, is unclear in contrast to adrenal tumors with mild autonomous cortisol secretion. The current systematic review and meta-analysis aimed to assess the burden of impaired glucose metabolism including diabetes mellitus type 2 (T2DM), fasting blood glucose (FBG), and fasting blood insulin (FBI) levels in patients with NFAI and 1-mg overnight dexamethasone suppression test (ODST) ≤ 1.8 μg/dl across published studies.

METHODS

We searched PubMed, Cochrane, and Scopus databases for identifying studies published between 1956 and March 2021. Twenty-five studies met the selection criteria including prospective, retrospective, and case-control studies. Two reviewers independently extracted studies, participants' characteristics and outcome data in a total pooled sample of 1548 patients.

RESULTS

Patients with NFAI had twofold [(odds ratio (OR) (95% confidence interval (CI)): 2.03 (1.39-2.98)] increased odds to present T2DM as well as higher FBG [weighted mean difference (WMD) (95% CI): 3.85 (1.96-5.74)] and homeostasis model assessment (HOMA) [WMD (95% CI): 0.68 (0.23-1.12)] with respect to controls. On the contrary, the WMD of FBI levels did not differ between the two groups. The incidence of T2DM in a subgroup analysis of patients with NFAI without glucose disorders at baseline was 6% [pooled incidence (95% CI): 0.06 (0.04-0.09)].

CONCLUSIONS

Patients with NFAI and 1-mg ODST ≤ 1.8 μg/dl presented higher odds of T2DM and higher levels of FBG and HOMA index than healthy controls.

Research on the distribution spectrum of atherosclerotic plaques in patients with suspected coronary artery disease and the noninvasive screening model for coronary atherosclerosis burden

BACKGROUND

This study aimed to establish a non-invasive and simple screening model of coronary atherosclerosis burden based on the associations between multiple blood parameters and total plaque score (TPS), segment-stenosis score (SSS), coronary artery disease severity (CADS) in coronary artery disease (CAD) and thus reduce unnecessary coronary angiography (CAG).

METHODS

A total of 1,366 patients with suspected CAD who underwent CAG were included in this study. The clinical risk factors [age, gender, systolic blood pressure (SBP), diastolic blood pressure (DBP), total cholesterol (TC), high-density lipoprotein (HDL), triglyceride (TG), low-density lipoprotein (LDL), fasting plasma glucose (FPG), and glycated hemoglobin (GHB)] were collected. The presence of plaques and lumen stenosis was assessed based on CAG imaging. The TPS, SSS, and CADS were calculated, and the distribution spectrum of atherosclerotic plaques was described. Kruskal-Wallis test for multiple comparison tests was performed to analyze the differences in groups of different risk factors. The selected independent predictors were put into a multivariate logistic model, and the variables were further screened by stepwise regression to establish a screening model. Finally, the receiver operating characteristic (ROC) curve was used to evaluate the selected model's discriminant effect.

RESULTS

The distributions of TPS and SSS scores were both right-skewed. Among males, both TPS and SSS scores were higher than in females (χ2=46.7659, P<0.0001, χ2=51.6603, P<0.0001). Both TPS and SSS scores increased with age (χ2=123.4456, P<0.0001, χ2=123.4456, P<0.0001). For TPS, the most common position was proximal left anterior descending artery (P-LAD, 51.39%). In SSS, the P-LAD plaque was highest: 0: 48.61%, 1: 10.32%, 2: 9.15%, and 3: 31.92%. The TPS score >5, SSS score >5, and CAD >0 were valuable indicators for SBP, FPG, TG, HDL, and GHB. In the model, TPS score >5, SSS score >5, and CADS >0, the area under ROC curve (AUC) was 0.753 [95% confidence interval (CI): 0.713 to 0.789], 0.728 (95% CI: 0.687 to 0.766), and 0.756 (95% CI: 0.717 to 0.793), respectively.

CONCLUSIONS

The most common site of lesions was P-LAD. These models can be used as non-invasive and simple initial screening tools without CAG.

Is there a role for the IGF system and epidermal growth factor (EGF) in the pathogenesis of adrenocortical adenomas? A preliminary case-control study

Adrenal incidentalomas (AI) are very common and mostly they are non-functioning adenomas (NFA). NFAs are often associated with insulin resistance and metabolic syndrome. Several biomarkers, including certain growth factors, may participatein the pathogenesis ofmetabolic changes in patients with adrenal adenomas.Patients with NFA and age-matched control subjects were enrolled in the study. Data on age, gender, presence of metabolic syndrome or its components were obtained for each subject. Blood samples were obtained and glycemia, insulinemia, lipid profile, and selected growth factor levels were measured. Forty-three patients with NFA and 40 controls were included in the study. Differences were not found in the metabolic syndrome and its components prevalence or in the biochemical profile between patients and the control group. Significant differences were noticed in the levels of IGF1, IGF2, and IGFBP3 (p=0.016, p=0.005, p=0.004, respectively), but there were no differences in VEGF or EGF concentrations. In NFA patients, an association between glycemia and EGF levels was present (p=0.026). No significant correlations between tumor size and insulin or growth factor concentrations were present in AI patients. Significantly higher serum IGF1, IGF2, and IGFBP3 concentrations in NFA patients may support the role of the IGF axis in the pathogenesis of adrenocortical lesions.No correlation between IGFs or IGFBP3 and parameters of glucose or lipid metabolism was found. Present results may support the role of the growth hormone axis rather than hyperinsulinemia and insulin resistance in the pathogenesis of adrenocortical adenomas.

Update on the risks of benign adrenocortical incidentalomas

PURPOSE OF REVIEW

Recent studies highlighted the association between adrenocortical incidentalomas and several comorbidities. This review summarizes the most recent evidence showing the potential risks related to adrenocortical tumors classified as nonfunctioning adrenal incidentalomas (NFAIs) or associated with clinically autonomous cortisol secretion (ACS).

RECENT FINDINGS

Alterations in glucose metabolism are a common finding in patients with ACS (30% of the cases). As shown in nonrandomized trials, surgical treatment may improve or cure diabetes in 52% of patients. Cross-sectional studies showed that NFAIs are also associated with insulin resistance. In a recent long-term retrospective study, patients with NFAI were at increased risk of developing prediabetes/diabetes during follow-up. Similarly, a prospective study showed that the incidence of prediabetes was higher also in tumors converting from NFAI to ACS. Patients with ACS are at increased risk of cardiovascular events and related mortality. Some cardiovascular markers were altered in patients with NFAI, even if a cause-effect relationship is not readily evident. Finally, 13% of NFAIs have increased risk of developing ACS during long-term follow-up.

SUMMARY

Patients with NFAI are at increased risk of developing alterations of glucose metabolism, whereas those with ACS or NFAI who converted to ACS over time are at risk for cardiovascular diseases.

Correlation of E-selectin concentrations with carotid intima-media thickness and cardio-metabolic profile of mixed ancestry South Africans: a cross-sectional study

Background E-selectin, an adhesion molecule, is a specific marker of endothelial dysfunction. High concentrations have been reported in type 2 diabetes and disorders with high risk of cardiovascular disease (CVD). Measurement of carotid intima-media thickness (CIMT) is a surrogate marker of early atherosclerosis. We examined the relationship between E-selectin concentrations, CIMT and cardio-metabolic traits in normo- and hyperglycaemic mixed ancestry South Africans. Methods E-selectin concentrations were determined in 308 subjects from the Cape Town Bellville South Community-based study on a mixed ancestry population. Their correlation with CIMT and cardio-metabolic profile used robust correlations and linear regression models. Results E-selectin concentrations were significantly higher in the hyperglycaemic (median 139.8 µg/L) compared to the normoglycaemic group (median 118.8 µg/L), ( p = 0.0007). Significant differences between the two groups were found for markers of glycaemia and adiposity, but not for CIMT. Significant correlations were found between E-selectin and age, markers of glycaemia and inflammation, central obesity and lipid variables. Associations remained significant only with age, hyperglycaemia and C-reactive protein in robust linear regression models. In similar regressions models, age and gender were the main predictors of CIMT, which was not associated with E-selectin. Conclusions E-selectin concentrations in this study were associated with hyperglycaemia, possibly reflecting early endothelial damage. However, E-selectin was not useful to assess CIMT, a marker of subclinical atherosclerosis, which appeared to be determined by ageing and male gender.