Insulin resistance and adrenal incidentalomas: A bidirectional relationship

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.

Diabetes Mellitus in Non-Functioning Adrenal Incidentalomas: Analysis of the Mild Autonomous Cortisol Secretion (MACS) Impact on Glucose Profile

Non-functioning adrenal incidentalomas (NFAIs) have been placed in relationship with a higher risk of glucose profile anomalies, while the full-blown typical picture of Cushing's syndrome (CS) and associated secondary (glucocorticoid-induced) diabetes mellitus is not explicitly confirmed in this instance. Our objective was to highlight the most recent data concerning the glucose profile, particularly, type 2 diabetes mellitus (T2DM) in NFAIs with/without mild autonomous cortisol secretion (MACS). This was a comprehensive review of the literature; the search was conducted according to various combinations of key terms. We included English-published, original studies across a 5-year window of publication time (from January 2020 until 1 April 2024) on PubMed. We excluded case reports, reviews, studies on T1DM or secondary diabetes, and experimental data. We identified 37 studies of various designs (14 retrospective studies as well 13 cross-sectional, 4 cohorts, 3 prospective, and 2 case-control studies) that analysed 17,391 individuals, with a female-to-male ratio of 1.47 (aged between 14 and 96 years). T2DM prevalence in MACS (affecting 10 to 30% of NFAIs) ranged from 12% to 44%. The highest T2DM prevalence in NFAI was 45.2% in one study. MACS versus (non-MACS) NFAIs (n = 16) showed an increased risk of T2DM and even of prediabetes or higher fasting plasma glucose or HbA1c (no unanimous results). T2DM prevalence was analysed in NFAI (N = 1243, female-to-male ratio of 1.11, mean age of 60.42) versus (non-tumour) controls (N = 1548, female-to-male ratio of 0.91, average age of 60.22) amid four studies, and two of them were confirmatory with respect to a higher rate in NFAIs. Four studies included a sub-group of CS compared to NFAI/MACS, and two of them did not confirm an increased rate of glucose profile anomalies in CS versus NFAIs/ACS. The longest period of follow-up with concern to the glycaemic profile was 10.5 years, and one cohort showed a significant increase in the T2DM rate at 17.9% compared to the baseline value of 0.03%. Additionally, inconsistent data from six studies enrolling 1039 individuals that underwent adrenalectomy (N = 674) and conservative management (N = 365) pinpointed the impact of the surgery in NFAIs. The regulation of the glucose metabolism after adrenalectomy versus baseline versus conservative management (n = 3) was improved. To our knowledge, this comprehensive review included one of the largest recent analyses in the field of glucose profile amid the confirmation of MACS/NFAI. In light of the rising incidence of NFAI/AIs due to easier access to imagery scans and endocrine evaluation across the spectrum of modern medicine, it is critical to assess if these patients have an increased frequency of cardio-metabolic disorders that worsen their overall comorbidity and mortality profile, including via the confirmation of T2DM.

Effect of Obesity on Clinical Characteristics of Primary Aldosteronism Patients at Diagnosis and Postsurgical Response

CONTEXT

Patients with obesity have an overactivated renin-angiotensin-aldosterone system (RAAS) that is associated with essential hypertension. However, the influence of obesity in primary aldosteronism (PA) is unknown.

OBJECTIVE

We analyzed the effect of obesity on the characteristics of PA, and the association between obesity and RAAS components.

METHODS

A retrospective study was conducted of the Spanish PA Registry (SPAIN-ALDO Registry), which included patients with PA seen at 20 tertiary centers between 2018 and 2022. Differences between patients with and without obesity were analyzed.

RESULTS

A total of 415 patients were included; 189 (45.5%) with obesity. Median age was 55 years (range, 47.3-65.2 years) and 240 (58.4%) were male. Compared to those without obesity, patients with obesity had higher rates of diabetes mellitus, chronic kidney disease, obstructive apnea syndrome, left ventricular hypertrophy, prior cardiovascular events, higher means of systolic blood pressure, and required more antihypertensive drugs. Patients with PA and obesity also had higher values of serum glucose, glycated hemoglobin A1c, creatinine, uric acid, and triglycerides, and lower levels of high-density lipoprotein cholesterol. Levels of blood aldosterone (PAC) and renin were similar between patients with and without obesity. Body mass index was not correlated with PAC nor renin. The rates of adrenal lesions on imaging studies, as well as the rates of unilateral disease assessed by adrenal vein sampling or I-6β-iodomethyl-19-norcholesterol scintigraphy, were similar between groups.

CONCLUSION

Obesity in PA patients involves a worse cardiometabolic profile, and need for more antihypertensive drugs but similar PAC and renin levels, and rates of adrenal lesions and lateral disease than patients without obesity. However, obesity implicates a lower rate of hypertension cure after adrenalectomy.

Prevalence and incidence of type 2 diabetes mellitus in patients with adrenal incidentalomas: a study of 709 cases

AIM

To evaluate the prevalence and incidence of type 2 diabetes in patients with nonfunctioning adrenal incidentalomas (NFAI) or adrenal incidentalomas (AI) with autonomous cortisol secretion (ACS).

METHODS

In this single-center retrospective study, all patients with adrenal incidentalomas ≥1 cm and ACS or NFAI studied between 2013 and 2020 were included. ACS was defined by a post-dexamethasone suppression test (DST) serum cortisol concentration ≥1.8 μg/dl, in the absence of signs of hypercortisolism, and NFAI was defined as a DST < 1.8 μg/dl without biochemical evidence of hypersecretion of other hormones.

RESULTS

Inclusion criteria were met by 231 patients with ACS and 478 with NFAI. At diagnosis, type 2 diabetes was present in 24.3% of patients. No differences were found in the prevalence of type 2 diabetes (27.7 vs. 22.6%, P = 0.137) between patients with ACS and NFAI. However, fasting plasma glucose values and glycated hemoglobin levels were significantly higher in patients with ACS than with NFAI (112 ± 35.6 vs. 105 ± 29 mg/dl, P = 0.004; and 6.5 ± 1.4 vs. 6.1 ± 0.9%, P = 0.005, respectively). Furthermore, patients with type 2 diabetes had higher urinary free cortisol (P = 0.039) and late-night salivary cortisol levels (P = 0.010) than those without type 2 diabetes. After a median follow-up of 28 months, no differences were found in the incidence of type 2 diabetes between the groups (HR 1.17, 95% 0.52-2.64).

CONCLUSION

Type 2 diabetes was present in one fourth of our cohort. We found no differences in its prevalence or incidence between the groups. However, glycemic control might be worse among diabetic patients with ACS. Higher concentrations of urinary and salivary cortisol were found in patients with than without type 2 diabetes.

Pathophysiological Link between Insulin Resistance and Adrenal Incidentalomas

Adrenal incidentalomas are incidentally discovered adrenal masses greater than one centimeter in diameter. An association between insulin resistance and adrenal incidentalomas has been established. However, the pathophysiological link between these two conditions remains incompletely characterized. This review examines the literature on the interrelationship between insulin resistance and adrenal masses, their subtypes, and related pathophysiology. Some studies show that functional and non-functional adrenal masses elicit systemic insulin resistance, whereas others conclude the inverse. Insulin resistance, hyperinsulinemia, and the anabolic effects on adrenal gland tissue, which have insulin and insulin-like growth factor-1 receptors, offer possible pathophysiological links. Conversely, autonomous adrenal cortisol secretion generates visceral fat accumulation and insulin resistance. Further investigation into the mechanisms and timing of these two pathologies as they relate to one another is needed and could be valuable in the prevention, detection, and treatment of both conditions.

Obesity, metabolic syndrome, and cancer: pathophysiological and therapeutic associations

Overweight, obesity, and metabolic syndrome (MetS) have become epidemic conditions affecting 39%, 13%, and 20% of the population respectively. The aim of this article is to review the literature on the association of obesity and MetS with the risk of cancer. We also explore the effect of lifestyle modifications, such as diet, physical activity, and antidiabetic medications, on cancer incidence. Increased body mass index (BMI) has been associated with a multitude of site-specific cancers, reaching relative risk (RR) 1.54 [95% confidence interval (CI) 1.47-1.61] per 5 unit increase for endometrial cancer, as well as with overall cancer risk (RR 1.03, 95% CI 1.02-1.05). Central adiposity measured by waist circumference or waist-to-hip ratio has been suggested as a stronger predictor than BMI for several cancers, such as colorectal cancer. Metabolic Syndrome has been consistently and positively associated with the risk of very common cancers like colorectal (RR 1.34, 95% CI 1.24-1.44), endometrial (RR 1.62, 95% CI 1.26-2.07) and postmenopausal breast cancer (RR 2.01, 95% CI 1.55-2.60). Hyperglycemia and subsequently T2DM have been also shown to increase the risk of cancer. Nevertheless, these risk factors are modifiable and therefore implementing lifestyle modifications could prevent an important number of cancer cases. Adherence to cancer prevention guidelines, including maintaining a healthy weight, having regular physical exercise (RR 0.58-0.90 for different cite specific cancers) and following a healthy dietary pattern (RR 0.74-0.94 for different cite specific cancers) have a protective effect on the risk of cancer. The strength of this review is the presentation of the best evidence, as the data derive mainly from meta-analyses. Public health policies should focus on the modification of risk factors and future research is needed to reveal the pathophysiological links between these risk factors and cancer to develop more efficient prevention and treatment strategies.

Diagnostic accuracy of the different hormonal tests used for the diagnosis of autonomous cortisol secretion

To evaluate the diagnostic accuracy of the different tests commonly used in the evaluation of adrenal incidentalomas (AIs) for the identification of autonomous cortisol secretion (ACS) and comorbidities potentially related to ACS. In a retrospective study of patients with AIs ≥ 1 cm, we evaluated the diagnostic reliability and validity of the dexamethasone suppression test (DST), urinary free cortisol (UFC), ACTH, late-night salivary cortisol (LNSC), and dehydroepiandrosterone-sulphate (DHEAS) for the diagnosis of comorbidities potentially related to ACS. Diagnostic indexes were also calculated for UFC, ACTH, LNSC, and DHEAS considering DST as the gold standard test for the diagnosis of ACS, using three different post-DST cortisol thresholds (138 nmol/L, 50 nmol/L and 83 nmol/L). We included 197 patients with AIs in whom the results of the five tests abovementioned were available. At diagnosis, 85.9% of patients with one or more AIs had any comorbidity potentially related to ACS, whereas 9.6% had ACS as defined by post-DST cortisol > 138 nmol/L. The reliability of UFC, ACTH, LNSC, and DHEAS for the diagnosis of ACS was low (kappa index < 0.30). Of them, LNSC reached the highest diagnosis accuracy for ACS identification (AUC = 0.696 [95% CI 0.626–0.759]). The diagnostic performances of these tests for comorbidities potentially related to ACS was poor; of them, the DST was the most accurate (AUC = 0.661 [95% CI 0.546–0.778]) and had the strongest association with these comorbidities (OR 2.6, P = 0.045). Patients presenting with increased values of both DST and LNSC had the strongest association with hypertension (OR 7.1, P = 0.002) and with cardiovascular events (OR 3.6, P = 0.041). In conclusion, LNSC was the test showing the highest diagnosis accuracy for the identification of ACS when a positive DST was used as the gold standard for its diagnosis. The DST test showed the strongest association with comorbidities potentially related to ACS. The definition of ACS based on the combination of elevated DST and LNSC levels improved the identification of patients with increased cardiometabolic risk.

Non-functioning adrenal incidentalomas may increase toxic metabolites

BACKGROUND

Non-functioning adrenal incidentaloma (NFAI) is a frequent diagnosis with increasing radiological tests. The emerging shreds of evidence showed that they might have negative cardiometabolic effects. The study aimed to investigate whether the toxic metabolites, asymmetric dimethylarginine (ADMA) levels, were altered in NFAI patients.

METHODS

We included 43 NFAI patients and 41 controls with similar ages and body mass indices in the study. We compared plasma ADMA levels of both groups and noted the radiological features of NFAIs.

RESULTS

The ADMA levels were significantly higher in NFAI patients than in the control group (307.04 ng/ml, range 81.89-577.7 ng/ml vs 192.54 ng/ml, range 70.61-440.26 ng/ml, p = 0.001). Nevertheless, we could not reach a significant correlation between ADMA levels and mass size.

CONCLUSION

The ADMA is known as a toxin and is increased in NFAI patients. NFAIs may not be innocent and may be considered a potential risk for the body. Further investigations were needed for more explanations.

Natural history of nonfunctioning adrenal incidentalomas: a 10-year longitudinal follow-up study

Most data on the natural history of nonfunctioning adrenal incidentalomas (NFAI) are provided by follow-ups up to 5 years. We conducted a 10.5 (9.1-11.9)-year prospective follow-up study of NFAI in 67 participants (20 (29.9%) males, 47 (70.1%) females) of mean age 57.9 (52.3-63.9) years and BMI 27.42 (24.07-30.56) kg/m2). We also evaluated the associations between baseline BMI and changes of NFAIs' characteristics at follow-up. Progression to mild autonomous cortisol excess (MACE) was observed in 15 (22 %) patients, with 14 of them having post overnight dexamethasone suppression test (ODST) cortisol between 50 and138 nmol/L and only one > 138 nmol/L. The progression rate was significantly higher in overweight and obese than in normal-weight subjects. Patients that developed MACE had a significantly higher baseline mean cortisol after 1 mg ODST. Tumor enlargement ≥10 mm occurred in 8.9% of patients. In comparison with reports of shorter observational periods, we observed a higher growth rate ≥ 10 mm and higher progression rate from NFAI to MACE, particularly in overweight and obese subjects. All tumors had persistent radiological characteristics typical for adrenal adenoma. We concluded that the duration of the follow-up period is an important factor in characterizing the natural history of NFAI. Higher baseline BMI and higher baseline cortisol after ODST might predict the long-term likelihood of progression in hormonal activity. The magnitudes of observed progressions in growth or hormonal activity were clinically insignificant. Our long-term follow-up, therefore, clearly supports the general view that a long-term monitoring of patients with NFAI is not necessary.

Menstrual Disorders and Androgen-Related Traits in Young Women with Type 1 Diabetes Mellitus: a Clinical Study

OBJECTIVE

To investigate possible causes of menstrual disorders and androgen-related traits in young women with type 1 diabetes mellitus (T1DM).

METHODS

Fifty-three women with T1DM (duration 8.0±5.6 years), 41 women with (polycystic ovary syndrome) PCOS, and 51 controls matched for age (19.4±4.3 years vs. 21.2±2.7 years vs. 20.8±3.1 years; P>.05) and body mass index (BMI) (22.2±2.7 kg/m2 vs. 21.9±2.0 kg/m2 vs. 21.4±1.9 kg/m2; P>.05) were prospectively recruited.

RESULTS

Two women (3.8%) in the T1DM group had not experienced menarche (at 15.5 and 16.6 years); of the rest, 23.5% had oligomenorrhea, 32.1% hirsutism, and 45.3% had acne. The age at menarche was delayed in the T1DM group compared to controls (12.7±1.3 vs. 12.0±1.0 years; P = .004), while no difference was observed with the polycystic ovary syndrome (PCOS) group (12.4±1.2 years). There were no differences in total testosterone (0.43±0.14 ng/mL vs. 0.39±0.14 ng/mL; P>.05), dehydroepiandrosterone sulfate (DHEA-S) (269 ± 112 μg/dL vs. 238 ± 106 μg/dL; P>.05) or Δ4-androstenedione (2.4±1.3 ng/mL vs. 1.9±0.5 ng/mL; P>.05) concentrations between T1DM and controls. However, patients with T1DM had lower sex hormone binding globulin (SHBG) concentrations than controls (61 ± 17 nmol/L vs. 83 ± 18.1 nmol/L; P = .001), which were even lower in the PCOS group (39.5±12.9 nmol/L; P = .001 compared with T1DM). The free androgen index (FAI) was higher in the PCOS group compared with both other groups (T1DM vs. PCOS vs. controls: 2.53±0.54 vs. 7.88±1.21 vs. 1.6 ± 0.68; P<.001). FAI was higher in patients with T1DM compared to controls as well (P = .038). There was no difference in DHEA-S concentrations between T1DM and PCOS patients (269 ± 112 μg/dL vs. 297 ± 100 μg/dL; P>.05).

CONCLUSION

Menstrual disorders and androgen-related traits in young women with T1DM may be attributed to an increase in androgen bioavailability due to decreased SHBG concentrations.

The prevalence and characteristics of non-functioning and autonomous cortisol secreting adrenal incidentaloma after patients' stratification by body mass index and age

BACKGROUND

The escalating prevalence of adrenal incidentaloma (AI) has been associated with the improvement of radiologic techniques and widespread imaging in aging population. It is currently unclear whether patients with obesity more likely develop AI and the current rise in the prevalence of AI could be at least partly associated with the respective rise in obesity. We compared the prevalence and characteristics of non-functional (NF) and autonomous cortisol secreting (ACS) adrenal incidentalomas (AIs) after the study population was stratified by different body mass indexes (BMI) and age groups.

METHODS

Retrospective cross-sectional study comprising of 432 patients (40.6% male, 59.4% female) with NFAI (N = 290) and ACS (N = 142), of median age 63.4 (54.0-71.6) years and median BMI 28.6 (25.5-31.7) kg/m². The data collection contained 11.132 points including demographic, anthropometric, radiologic, hormonal and metabolic parameters.

RESULTS

We observed 68-87% higher prevalence of AI across different age groups in NFAI and ACS in obese/overweight compared to normal weight subjects. Patients with ACS were older (P = 0.008), with higher basal cortisol (P < 0.001), lower basal DHEAS (P = 0.001), lower suppression DHEAS (P = 0.027) and higher aldosterone (P = 0.039). AIs with ACS were larger than NFAI (P < 0.001). Interestingly, ACS group had lower body mass (P = 0.023) and did not differ in BMI, blood pressure, heart rate, lipid profile, fasting glucose and presence of diabetes mellitus type 2 when compared to NFAI., By contrast to the similarity of metabolic profiles in ACS and NFAI, some components of adverse metabolic traits were rather associated with higher BMI and older age, in particular in NFAI.

CONCLUSION

The prevalence of NFAI and ACS were significantly higher in overweight/obese subgroup across the age distribution. Stratification by age and BMI displayed significant differences in some metabolic traits, in particular in NFAI.

Glucose metabolism disorders in patients with adrenal gland disorders: pathophysiology and management

The aim of this review is to explore and discuss disorders of glucose metabolism that can arise in individuals with adrenal gland disorders, as well as to enumerate the available therapeutic treatments for these while considering their benefits and drawbacks. Hyperfunctioning adrenal glands, as in hypercortisolism, hyperaldosteronism, and malignancy, or hypofunctioning of adrenal glands, as in adrenal insufficiency, can lead to carbohydrate metabolism dysregulation with subsequent glucometabolic repercussions, either hyperglycemia or hypoglycemia. Glycemic disorders further affect patients' quality of life and represent a therapeutic dilemma for physicians. Current management strategies for glycemic dysregulation in individuals with adrenal gland disorders are fighting the underlying causes, as well as utilizing antidiabetic therapies that aid in maintaining euglycemia. Further research focused on discovering drug preparations of greater accuracy and effectiveness tailored to patients with adrenal problems as well as studies investigating optimal lifestyle management models for these individuals will assist towards achieving optimal regulation of glucose metabolism.

Adrenal Incidentalomas are Tied to Increased Risk of Diabetes: Findings from a Prospective Study

CONTEXT

The frequency of adrenal incidentalomas and their association with comorbid conditions have been assessed mostly in retrospective studies that may be prone to ascertainment bias.

OBJECTIVE

The objective of this work is to evaluate the frequency of adrenal incidentalomas and their associated comorbid conditions.

DESIGN

A prospective cohort study was conducted.

SETTING

This study took place at a radiology department at a public hospital.

PARTICIPANTS

Unselected outpatients who underwent an abdominal computed tomography (CT) from January 2017 to June 2018. Patients with known or suspected adrenal disease or malignancy were excluded.

EXPOSURE

All abdominal CT scans were evaluated by an experienced radiologist. Hormonal workup including a 1-mg dexamethasone suppression test was performed in patients bearing adrenal incidentalomas.

MAIN OUTCOME AND MEASURE

Frequency of adrenal incidentalomas in abdominal CT of unselected patients; frequency of comorbid conditions, and hormonal workup in patients bearing adrenal incidentalomas.

RESULTS

We recruited 601 patients, and in 7.3% of them an adrenal tumor was found serendipitously. The patients bearing an adrenal incidentaloma had higher body mass index (P = .009) and waist circumference (P = .004) and were more frequently diabetic (P = .0038). At multivariable regression analysis, diabetes was significantly associated with the presence of adrenal incidentalomas (P = .003). Autonomous cortisol secretion was observed in 50% of patients who did not suppress cortisol less than 50 nmol/L after 1 mg dexamethasone.

CONCLUSIONS

The frequency of adrenal incidentalomas is higher than previously reported. Moreover, adrenal incidentalomas are tied to increased risk of type 2 diabetes. This finding is free from ascertainment bias because patients with adrenal incidentalomas were drawn from a prospective cohort with the same risk of diabetes as the background population.

Is Follow-up of Adrenal Incidentalomas Always Mandatory?

Adrenal masses are mainly detected unexpectedly by an imaging study performed for reasons unrelated to any suspect of adrenal diseases. Such masses are commonly defined as "adrenal incidentalomas" and represent a public health challenge because they are increasingly recognized in current medical practice. Management of adrenal incidentalomas is currently matter of debate. Although there is consensus on the need of a multidisciplinary expert team evaluation and surgical approach in patients with significant hormonal excess and/or radiological findings suspicious of malignancy demonstrated at the diagnosis or during follow-up, the inconsistency between official guidelines and the consequent diffuse uncertainty on management of small adrenal incidentalomas still represents a considerable problem in terms of clinical choices in real practice. The aim of the present work is to review the proposed strategies on how to manage patients with adrenal incidentalomas that are not candidates to immediate surgery. The recent European Society of Endocrinology/European Network for the Study of Adrenal Tumors guidelines have supported the view to avoid surveillance in patients with clear benign adrenal lesions <4 cm and/or without any hormonal secretion; however, newer prospective studies are needed to confirm safety of this strategy, in particular in younger patients.

Cardiometabolic profile of non-functioning and autonomous cortisol-secreting adrenal incidentalomas. Is the cardiometabolic risk similar or are there differences?

OBJECTIVE

To study the differences in the cardiometabolic profile between patients with non-functioning adrenal incidentalomas (NFAI) and incidentalomas with autonomous cortisol secretion (ACS).

METHODS

A total of 149 patients with adrenal incidentalomas were retrospectively evaluated and followed-up for a mean time of 34.6 months at Departments of Endocrinology and Metabolic Diseases Units of four tertiary Spanish hospitals. Patients were grouped as NFAI or ACS adenomas based on two cutoffs in the dexamethasone suppression test (DST): 3.0 µg/dl (NFAI_DST3 or ACS_DST3) and 1.8 µg/dl (ACS_DST1.8 and NFAI_DST1.8).

RESULTS

The mean age of both groups was 62.0 (10.31) and was similar in ACS and NFAI. The prevalence of diabetes, high blood pressure, cardiovascular, and cerebrovascular disease was higher in ACS than in NFAI, but differences only reached statistical significance for cerebrovascular disease using the 3.0 µg/dl cutoff (15.8% vs 2.3%, p = 0.01) and for diabetes using the 1.8 µg/dl cutoff (38.0% vs 22.0%, p = 0.04). No differences were found in the prevalence of dyslipidemia. The prevalence of obesity was lower in patients with ACS than in NFAI 26.3% vs 39.2%, p = 0.18 (NFAI_DST3 vs ACS_DST3) and 32.1% vs 40.6%, p = 0.56 (ACS_DST1.8 vs NFAI_DST1.8), but the differences did not reach statistical significance. Maximum adenoma diameter (R-squared = 0.15, p < 0.001) and cerebrovascular disease (OR = 1.59, p = 0.04) were the only parameters that could be predicted by the DST. The DST was an inadequate predictor of clinical (systolic and diastolic blood pressure, body mass index), hormonal (DHEAS, ACTH, UFC, and basal serum cortisol), biochemical (glucose, cholesterol, LDL, HDL, and triglycerides), and other radiological (laterality, lipid content) parameters. Throughout the follow-up, patients did not develop overt Cushing's Syndrome; three NFAI_DST3 developed ACS_DST3, eight NFAI_DST1.8 developed ACS_DST1.8, and one NFAI_DST1.8 progressed to ACS_DST3. In both groups (NFAI and ACS) the metabolic profile remained stable.

CONCLUSIONS

Our data suggest higher prevalence of diabetes and cerebrovascular disease in ACS patients compared with NFAI. However, probably because of the small sample size, the differences only reached statistical significance using the cutoffs of 1.8 µg/dl for diabetes and 3.0 µg/dl for cerebrovascular disease. Patients with ACS and NFAI rarely progress to more aggressive forms of hypercortisolism, and the metabolic profile usually remains stable during the follow-up.