Nonfunctioning and Subclinical Cortisol Secreting Adrenal Incidentalomas and their Association with Metabolic Syndrome: A Systematic Review

Association between smoking and alcohol drinking and benign adrenal tumors: a Mendelian randomization study

BACKGROUND

In recent years, the detection rate of adrenal tumors has increased, but it is unclear whether smoking and alcohol drinking are risk factors for benign adrenal tumors. The objective of this study is to employ Mendelian randomization (MR) analysis to explore the causal relationship between smoking, alcohol drinking and susceptibility to benign adrenal tumors.

METHODS

We acquired large-scale data from publicly accessible databases on genome-wide association studies (GWAS) pertaining to smoking, alcohol drinking and benign adrenal tumors. A total of 11 sets of instrumental variables (IVs) and 281 associated single nucleotide polymorphic (SNP) loci were identified. The Mendelian randomization analyses were conducted using inverse variance weighting (IVW), MR-Egger regression and weighted median estimation (WME) methods, in addition to sensitivity analyses.

RESULTS

There is no causal relationship between smoking status, alcohol drinking status, alcohol intake frequency, alcohol taken with meals, alcohol consumption and benign adrenal tumors, while pack years of smoking and cigarettes per day are risk factors for benign adrenal tumors. The IVW analysis revealed that both the pack years of smoking and cigarettes per day were positively associated with an increased risk of benign adrenal tumors (OR = 2.853, 95%CI = 1.384-5.878, p = 0.004; OR = 1.543, 95%CI = 1.147-2.076, p = 0.004). Two SNPs (rs8042849 in the analysis of pack years of smoking and rs8034191 in the analysis of cigarettes per day) significantly drove the observed causal effects.

CONCLUSION

Two-sample Mendelian randomization analysis showed a causal effect between smoking but not alcohol consumption and benign adrenal tumors.

Comparison of adrenalectomy with conservative treatment on mild autonomous cortisol secretion: a systematic review and meta-analysis

Objective

This systematic review and meta-analysis was conducted to compare the benefits of adrenalectomy and conservative treatment for comorbidities associated with mild autonomous cortisol secretion (MACS) in patients diagnosed with MACS.

Background

MACS is the most common benign hormone-secreting functional adrenal incidentaloma. Overproduction of cortisol is observed in MACS patients, resulting in a variety of long-term health issues, including arterial hypertension (HTN), diabetes mellitus (DM), dyslipidemia, obesity, and osteoporosis; however, the classic clinical manifestations of Cushing's syndrome (CS) are not present.

Methods

A systematic search was conducted using MEDLINE, Embase, Web of Sciences, and Scopus databases on December, 2023. Two reviewers independently extracted data and assessed the quality of the included articles. A meta-analysis was performed to compare the beneficial effects of adrenalectomy versus conservative management for MACS-related comorbidities.

Results

Fifteen articles were included in this study, which evaluated 933 MACS patients (384 Adrenalectomy and 501 Conservative treatment, and 48 excluded due to incomplete follow-up duration). MACS diagnosis criteria were different among the included articles. All studies, however, stated that there must be no overt CS symptoms. Meta-analysis demonstrates the overall advantage of adrenalectomy over conservative treatment for MACS-related comorbidities (Cohen's d = -0.49, 95% CI [-0.64, -0.34], p = 0.00). Subgroup analysis indicated that the systolic blood pressure (pooled effect size = -0.81, 95% CI [-1.19, -0.42], p = 0.03), diastolic blood pressure (pooled effect size = -0.63, 95% CI [-1.05, -0.21], p = 0.01), and BMD (pooled effect size = -0.40, 95% CI [-0.73, -0.07], p = 0.02) were significantly in favor of adrenalectomy group rather than conservative treatment but no significant differences between the two treatment groups in other MACS-related comorbidities were reported.

Conclusion

Despite the limited and diverse data, this study demonstrates the advantage of adrenalectomy over conservative treatment for MACS-related comorbidities.

Mild autonomous cortisol secretion: pathophysiology, comorbidities and management approaches

The majority of incidentally discovered adrenal tumours are benign adrenocortical adenomas and the prevalence of adrenocortical adenomas is around 1-7% on cross-sectional abdominal imaging. These can be non-functioning adrenal tumours or they can be associated with autonomous cortisol secretion on a spectrum that ranges from rare clinically overt adrenal Cushing syndrome to the much more prevalent mild autonomous cortisol secretion (MACS) without signs of Cushing syndrome. MACS is diagnosed (based on an abnormal overnight dexamethasone suppression test) in 20-50% of patients with adrenal adenomas. MACS is associated with cardiovascular morbidity, frailty, fragility fractures, decreased quality of life and increased mortality. Management of MACS should be individualized based on patient characteristics and includes adrenalectomy or conservative follow-up with treatment of associated comorbidities. Identifying patients with MACS who are most likely to benefit from adrenalectomy is challenging, as adrenalectomy results in improvement of cardiovascular morbidity in some, but not all, patients with MACS. Of note, diagnosis and management of patients with bilateral MACS is especially challenging. Current gaps in MACS clinical practice include a lack of specific biomarkers diagnostic of MACS-related health outcomes and a paucity of clinical trials demonstrating the efficacy of adrenalectomy on comorbidities associated with MACS. In addition, little evidence exists to demonstrate the efficacy and safety of long-term medical therapy in patients with MACS.

New-onset diabetes mellitus risk associated with concurrent autonomous cortisol secretion in patients with primary aldosteronism

Concurrent autonomous cortisol secretion (ACS) in patients with primary aldosteronism (PA patients) is not uncommon. This work aimed to determine the effect of cortisol levels on incident new-onset type 2 diabetes mellitus (NODM) in PA patients. Using the prospectively designed observational TAIPAI cohort, the PA patients were grouped by cortisol level after an overnight low-dose dexamethasone suppression test (1-mg DST). Of the 476 PA patients, 387 (43.7% men; mean age 52.8 years) did not have baseline DM. After a mean follow-up of 4.3 ± 2.9 years, 32 patients (8.3%) developed NODM. The cutoff value obtained via a generalized additive model showed that a serum cortisol level ≥ 2.65 µg/dL after 1-mg DST was a risk factor for developing NODM (HR, 3.5, p = 0.031) by Cox proportional- hazards model.. In PA patients with a higher body mass index (>25 kg/m²; HR, 3.16), lower estimated glomerular filtration rate (<90 ml/min/1.73 m²; HR, 3.18), longer hypertension duration (>7 years; HR, 3.34), and higher waist-to-hip ratio (>0.9; HR, 3.07), a concomitant cortisol level ≥ 2.65 μg/dL after 1-mg DST were more likely to develop NODM. The high-cortisol group of patients with aldosterone-producing adenoma (APA) using mineralocorticoid receptor antagonist (MRA) was associated with an increased risk of NODM (HR, 5.72). Our results showed that PA patients with a concomitant cortisol level ≥ 2.65 µg/dL after 1-mg DST, independent of the aldosterone level, had a higher incidence of NODM. Such PA patients should be carefully evaluated and managed to achieve better glucose control and prevent metabolic syndrome.

Possible, probable, and certain hypercortisolism: A continuum in the risk of comorbidity

Hypercortisolism may be considered as a continuum in terms of both hormonal and cardiometabolic abnormalities. It ranges from cases with "normal" hormonal profile and low to intermediate risk of comorbidity to florid cases with clear clinical and hormonal evidence of glucocorticoid excess and clearly increased cardiometabolic risk. Even in patients with nonfunctioning adrenal incidentaloma (NFAI), defined as adrenal incidentaloma with normal results on the currently available hormonal test for evaluation of hypercortisolism, cardiometabolic and mortality risk is higher than in the general population without adrenal lesions. Mild hypercortisolism or autonomous cortisol secretion (ACS) is a term used for patients with adrenal incidentaloma and pathological dexamethasone suppression test (DST) results, but without specific clinical signs of hypercortisolism. It is widely known that this condition is linked to higher prevalence of several cardiometabolic comorbidities, including diabetes, hypertension, osteoporosis and metabolic syndrome, than in patients with NFAI or without adrenal tumor. In case of overt Cushing's syndrome, cardiovascular risk is extremely high, and standard mortality ratio is high, cardiovascular disease being the leading cause of death. The present review summarizes the current evidence for a detrimental cardiometabolic profile in patients with possible (NFAI), probable (ACS) and certain hypercortisolism (overt Cushing's syndrome).

Evaluation of Body Composition in Patients With and Without Adrenal Tumors and Without Overt Hypersecretory Syndromes

OBJECTIVE

To compare body composition between patients with autonomous cortisol secretion (ACS), those with nonfunctioning adrenal incidentalomas (NFAIs), and control subjects without adrenal tumors.

METHODS

A cross-sectional study was performed, incluidng the following 3 groups: patients with ACS (cortisol post-dexamethasone suppression test [DST] >1.8 μg/dL), NFAIs (cortisol post-DST ≤ 1.8 μg/dL), and patients without adrenal tumors (control group). Patients of the 3 groups were matched according to age (±5 years), sex, and body mass index (±5 kg/m²). Body composition was evaluated by bioelectrical impedance and abdominal computed tomography (CT) and urinary steroid profile by gas chromatography mass spectrometry.

RESULTS

This study enrolled 25 patients with ACS, 24 with NFAIs, and 24 control subjects. Based on CT images, a weak positive correlation between the serum cortisol level post-DST and subcutaneous fat area (r = 0.3, P =.048) was found. As assessed by bioelectrical impedance, lean mass and bone mass were positively correlated with the excretion of total androgens (r = 0.56, P <.001; and r = 0.58, P <.001, respectively); visceral mass was positively correlated with the excretion of glucocorticoid metabolites and total glucocorticoids (r = 0.28, P =.031; and r = 0.42, P =.001, respectively). Based on CT imaging evaluation, a positive correlation was observed between lean mass and androgen metabolites (r = 0.30, P =.036) and between visceral fat area, total fat area, and visceral/total fat area ratio and the excretion of glucocorticoid metabolites (r = 0.34, P =.014; r = 0.29, P =.042; and r = 0.31, P =.170, respectively).

CONCLUSION

The urinary steroid profile observed in adrenal tumors, comprising a low excretion of androgen metabolites and high excretion of glucocorticoid metabolites, is associated with a lower lean mass and bone mass and higher level of visceral mass in patients with adrenal tumors.

Automated extraction of incidental adrenal nodules from electronic health records

BACKGROUND

Many adrenal incidentalomas do not undergo appropriate biochemical testing and complete imaging characterization to assess for hormone hypersecretion and malignancy. With the growing availability of clinical narratives in the electronic medical record, automated surveillance using advanced data analytic techniques may represent a promising method to improve management.

METHODS

A data provisioning process using a series of structured query language scripts was used to abstract all chest and abdominal computed tomography and magnetic resonance imaging reports from an academic health care system in 2018. The narratives and impressions were queried for key text relating to the identification of adrenal incidentalomas. Patients with a history of extra-adrenal malignancy undergoing staging or surveillance imaging were excluded. The prevalence and radiographic characteristics were analyzed. Patients with adrenal incidentalomas newly identified in 2018 were assessed for biochemical testing and nodule stability through August 2021.

RESULTS

Of 36,618 patients queried, 8,557 were excluded owing to a history of extra-adrenal malignancy. Data from 447 patients were flagged by the structured query language scripts and electronically abstracted. On internal validation, 307/447 (69%) patients were correctly identified as having adrenal nodules (1.1% overall prevalence). The median patient age was 67 years, and 56% were female. The median nodule size was 1.7 (IQR 1.3-2.5) cm, 9% were bilateral, and 63% were low density (unenhanced Hounsfield units <10). Adrenal carcinoma was identified in 10 patients. In 2018, 121 patients were diagnosed with a new adrenal incidentaloma. Of 32 (27%) patients who had follow-up imaging at a median of 1.9 years, 97% of nodules were stable in size. Biochemical testing was performed in 53 patients (44%), of which 31 (26%) had complete hormonal assessment; 14 (26%) were functional nodules: 7 aldosterone-secreting, 4 cortisol-secreting, and 3 pheochromocytoma.

CONCLUSION

Only one-fourth of patients received appropriate biochemical testing after incidental diagnosis of an adrenal nodule, and most nodules with indeterminate imaging characteristics did not undergo follow-up imaging. Advanced data analytic techniques on electronic imaging reports may aid in the clinical identification and improved management of patients with adrenal incidentalomas.

Cardiometabolic profile and urinary metabolomic alterations in non-functioning adrenal incidentalomas: A review

BACKGROUND

The incidence of adrenal incidentalomas (AIs) has increased over the last 20 years, most of which are apparently non-functioning adrenal adenomas. However, increased evidence supports the existence of an association between non-functioning adrenal incidentalomas (NFAI) and an unfavourable cardio-metabolic profile.

METHODS

This study offers a comprehensive review of the available evidence supporting a higher cardiometabolic risk in NFAIs compared to controls without adrenal tumours. Moreover, it summarises the studies focused on the differential urinary metabolomic profile of NFAI and controls without adrenal lesions.

RESULTS

This adverse metabolic profile of patients with NFAI includes a higher prevalence of insulin resistance, obesity, hypertension, hyperglycaemia, dyslipidaemia, and cardiovascular alterations and mortality compared to healthy controls without adrenal tumours. Although the pathophysiology that explains the association between NFAI and the parameters of metabolic syndrome and cardiovascular risk is a relatively unexplored field of study, some evidence supports that there are a series of incipient alterations in cortisol metabolism not detected with the classical tests that led to this detrimental profile. These alterations may be potentially detected by a comprehensive metabolomics approach. Several studies detected a shift towards an increase of urinary cortisol metabolites excretion in NFAIs compared to controls without adrenal tumours.

CONCLUSION

In view of the higher cardiometabolic risk in NFAI than in controls without adrenal tumours, and the detected alterations in metabolomics profile of NFAI, I propose that the term of NFAI should be changed for another term that best fits to its linked cardiometabolic profile.

Adrenalectomy improves blood pressure control in nonfunctioning adrenal incidentalomas and glycemic and lipid control in patients with autonomous cortisol secretion

PURPOSE

To compare the evolution of the cardiometabolic parameters in patients with nonfunctioning adrenal incidentalomas (NFAI) and autonomous cortisol secretion (ACS) who underwent adrenalectomy and those who were conservatively managed.

METHODS

A retrospective study of all patients with NFAI and ACS submitted to surgery or in follow-up in our center between January 2011-October 2020. NFAI was defined as an adrenal incidentaloma with cortisol post-dexamethasone suppression test (DST) ≤ 50 nmol/L and ACS as values >50 nmol/L without specific clinical signs of overt Cushing´s syndrome.

RESULTS

A total of 486 patients with NFAI (16 in the surgical group and 470 in the control group) and 259 with ACS (42 in the surgical group and 217 in the control group) were included. At baseline, patients with ACS were older than those with NFAI (P = 0.010). After adjusting by age, patients with ACS had a higher prevalence of hypertension (adjusted OR = 1.9 [1.36-2.60]) and higher levels of fasting plasma glucose and HbA1c (adjusted β = 6.9 [2.05-11.83] and adjusted β = 0.4 [0.12-0.63]) than NFAI. During follow-up, ACS patients who underwent adrenalectomy had a greater decrease in glucose levels (-16.6 ± 45.07 vs. -1.0 ± 26.92 mg/dL, P = 0.035) and in triglycerides (-20.21 ± 55.97 vs. 1.3 ± 59.23 mg/dL, P = 0.029) than ACS patients conservatively managed. NFAI patients who underwent surgery experienced an improvement in systolic blood pressure compared to NFAI of the conservative group (-11.1 ± 15.94 vs 1.0 ± 17.54 mmHg, P = 0.009).

CONCLUSION

The benefits of adrenalectomy in the cardiometabolic profile in adrenal incidentalomas are not limited only to the group of patients with ACS, an improvement in blood pressure control is also observed in NFAI patients after surgery.

The heart-brain axis: A proteomics study of meditation on the cardiovascular system of Tibetan Monks

Background

There have been mixed reports on the beneficial effects of meditation in cardiovascular disease (CVD), which is widely considered the leading cause of death worldwide.

Methods

To clarify the role of meditation in modulating the heart-brain axis, we implemented an extreme phenotype strategy, i.e., Tibetan monks (BMI > 30) who practised 19.20 ± 7.82 years of meditation on average and their strictly matched non-meditative Tibetan controls. Hypothesis-free advanced proteomics strategies (Data Independent Acquisition and Targeted Parallel Reaction Monitoring) were jointly applied to systematically investigate and target the plasma proteome underlying meditation. Total cholesterol, low-density lipoprotein cholesterol  (LDL-C), apolipoprotein B (Apo B) and lipoprotein (a) [Lp(a)] as the potential cardiovascular risk factors were evaluated. Heart rate variability (HRV) was assessed by electrocardiogram.

Findings

Obesity, hypertension, and reduced HRV is offset by long-term meditation. Notably, meditative monks have blood pressure and HRV comparable to their matched Tibetan controls. Meditative monks have a protective plasma proteome, related to decreased atherosclerosis, enhanced glycolysis, and oxygen release, that confers resilience to the development of CVD. In addition, clinical risk factors in plasma were significantly decreased in monks compared with controls, including total cholesterol, LDL-C, Apo B, and Lp(a).

Interpretation

To our knowledge, this work is the first well-controlled proteomics investigation of long-term meditation, which opens up a window for individuals characterized by a sedentary lifestyle to improve their cardiovascular health with an accessible method practised for more than two millennia.

Funding

See the Acknowledgements section.

Association between Tumor Size and Malignancy Risk in Hormonally Inactive Adrenal Incidentalomas

Introduction

Adrenal incidentalomas (AI) are adrenal masses that are discovered during radiological examinations conducted for other reasons. In this study, we focused on the pathological and radiological properties of nonfunctional AI(NFAI) and the association with malignancy risk in our clinical series.

Methods

A total of 186 patients underwent adrenalectomy between 2010 and 2017; of these, 76 (40.8%) patients with non-functional AI were included in the current study. The radiological and pathologic characteristics of these AIs were retrospectively analyzed to determine the malignancy rate.

Results

There were 22 (28.9%) male and 54 (71.1%) female patients with nonfunctional AI included in this study. The median age was 55 (range: 24-85) years. Of the patients included, 37 (48.6%) had AI on the left and 39 (51.3%) had AI on the right adrenal gland. Sixty-one (80.2%) cases were treated laparoscopically, four (5.3%) required conversion to open surgery due to intraoperative difficulties such as bleeding and adhesions, and 11 (14.4%) were managed with open adrenalectomy. The rate of malignancy in the tumors with diameters of <4 cm, 4-6 cm, and >6 cm was found to be 0%, 2.9%, and 13.6%, respectively.

Conclusions

Determining the ideal cutoff value for surgical indication in an NFAI is challenging. Besides the malignancy risk, the rate of silent pheochromacytomas must be taken into account in the surgical decision.