Bone metabolism and mass in women with Cushing's syndrome and adrenal incidentaloma

Management of Adrenal Cortical Adenomas: Assessment of Bone Status in Patients with (Non-Functioning) Adrenal Incidentalomas

Our aim is to analyse the bone profile in adults with (non-functioning) adrenal incidentalomas (AIs), specifically addressing the impact of autonomous cortisol secretion (ACS). This narrative review, based on a PubMed search from inception to February 2023 (case reports, non-ACS, and other secondary causes of osteoporosis were excluded), included 40 original studies, a total of 3046 patients with female prevalence (female:male ratio of 1921:1125), aged between 20.5 and 95.5 years old. This three decade-based analysis showed that 37 studies provided dual-energy X-ray absorptiometry (DXA) information; another five studies reports results on bone micro-architecture, including trabecular bone score (TBS), spinal deformity index, and high-resolution peripheral quantitative computed tomography; 20 cohorts included data on bone turnover markers (BTMs), while four longitudinal studies followed subjects between 1 and 10.5 years old (surgical versus non-adrenalectomy arms). Post-dexamethasone suppression test (DST) cortisol was inversely associated with bone mineral density (BMD). TBS predicted incidental vertebral fractures (VFx) regardless of BMD, being associated with post-DST cortisol independently of age and BMD. Low BTMs were identified in ACS, but not all studies agreed. An increased prevalence of ACS-related osteoporosis was confirmed in most studies (highest prevalence of 87.5%), as well as of VFx, including in pre-menopause (42.5%), post-menopause (78.6%), and male patients (72.7%) depending on the study, with a 10-fold increased incidental VFx risk up to a 12-fold increased risk after a 2-year follow-up. No specific medication against osteoporosis is indicated in ACS, but adrenalectomy (according to four studies) should be part of the long-term strategy. This bone profile case sample-based study (to our knowledge, one of the largest of its kind) showed that AIs, including the subgroup designated as having ACS, embraces a large panel of osseous complications. The level of evidence remains far from generous; there are still no homogenous results defining ACS and identifying skeletal involvement, which might be a consequence of different investigation clusters underling adrenal and bone assessments over time. However, bone status evaluations and associated therapy decisions remain an essential element of the management of adults with AIs-ACS.

Comorbidities in Mild Autonomous Cortisol Secretion - A Clinical Review of Literature

Mild autonomous cortisol secretion (mACS) is a state of cortisol excess usually associated with existence of adrenal incidentaloma. Because of the lack of symptoms of the disease, the biochemical evaluation is the most important to determine a diagnosis. However, scientific societies have different diagnostic criteria for mACS, which makes the treatment of this disease and using results of original papers in daily practice more difficult. Chronic hypercortisolemic state, even if mild, may lead to diseases that are mostly connected with overt Cushing's syndrome. Some of them can cause a higher mortality of patients with mACS and those problems need to be addressed. In this review we describe the comorbidities associated with mACS: cardiovascular disorders, arterial hypertension, diabetes mellitus, insulin resistance, dyslipidemia, obesity, metabolic syndrome, non-alcoholic fatty liver disease, vertebral fractures and osteoporosis. The point of this paper is to characterise them and determine if and how these conditions should be managed. Two databases - PubMed and Web of Science were searched. Even though the evidence are scarce, this is an attempt to lead clinicians through the problems associated with this enigmatic condition.

Association of urinary free cortisol with bone formation in patients with mild autonomous cortisol secretion

CONTEXT

Mild autonomous cortisol secretion (ACS) is associated with an increased risk of vertebral fractures (VFx). However, the influence of this condition on bone turnover or its association with mild ACS is still controversial.

OBJECTIVE

This study aimed to evaluate the impact of mild ACS on bone quality among patients living with the disease.

DESIGN AND SETTING

A retrospective study was conducted using data from 55 mild ACS and 12 nonfunctioning adrenal tumour (NFT) patients who visited Chiba University Hospital, Japan, from 2006 to 2018.

PATIENTS AND MAIN OUTCOME MEASURES

We analysed clinical features and bone-related factors, including bone mineral density (BMD) and VFx, performed blood tests to assess bone metabolism markers in patients with mild ACS and NFT, and assessed the associations between bone-related markers and endocrinological parameters in patients with mild ACS.

RESULTS

No significant differences between mild ACS and NFT patients were observed with respect to the presence or absence of VFx and BMD. Urinary free cortisol (UFC) was higher in mild ACS patients with VFx than those without (p = .037). The T-score and young adult mean (YAM) of the BMD of the femoral neck in mild ACS patients with a body mass index <25 were positively correlated with dehydroepiandrosterone sulphate levels (ρ: 0.42, p = .017; ρ: 0.40, p = .024, respectively). Pearson's correlation analysis showed that bone-specific alkaline phosphatase was negatively correlated with UFC in the patients with mild ACS (ρ: -0.37, p = .026).

CONCLUSIONS

These results suggest that urinary free cortisol may be useful for predicting bone formation in mild ACS patients.

Osteopathy in mild adrenal Cushing's syndrome and Cushing disease

Pathophysiology and effects of endogenous glucocorticoid (GC) excess on skeletal endpoints as well as awareness and management of bone fragility are reviewed. Cushing's syndrome (CS) increase the risk of fracture affecting prevalently bone quality. Bone antiresorptive agents (SERMs, bisphosphonates and denosumab) as well as teriparatide increase bone mineral density and in some instances reduce fracture risk. Awareness and management of bone health in CS can be improved.

Adrenal Incidentaloma

An adrenal incidentaloma is now established as a common endocrine diagnosis that requires a multidisciplinary approach for effective management. The majority of patients can be reassured and discharged, but a personalized approach based upon image analysis, endocrine workup, and clinical symptoms and signs are required in every case. Adrenocortical carcinoma remains a real concern but is restricted to <2% of all cases. Functional adrenal incidentaloma lesions are commoner (but still probably <10% of total) and the greatest challenge remains the diagnosis and optimum management of autonomous cortisol secretion. Modern-day surgery has improved outcomes and novel radiological and urinary biomarkers will improve early detection and patient stratification in future years to come.

Biochemical bone turnover markers in hormonal disorders in adults: a narrative review

BACKGROUND

Hormonal disorders are often associated with abnormal levels of bone turnover markers (BTMs). N-terminal propeptide of type I procollagen (PINP) and serum C-terminal cross-linking telopeptide of type I collagen (CTX-I) are the reference markers of bone formation and bone resorption, respectively.

METHODS

A comprehensive literature search within the MEDLINE and Web of Science databases was performed.

RESULTS

Acromegaly is associated with higher BTM levels, which decrease during the remission after treatment. Adult-onset growth hormone deficiency is often associated with decreased BTM levels. Growth hormone replacement therapy stimulates bone turnover and increases BTM levels. Hypothyroidism is characterized by general slowing of bone metabolism which is reflected by lower BTM levels. The replacement thyroid hormone therapy increases the bone turnover rate and BTM levels increase. Patients with thyroid cancer receive a suppressive dose of thyroid hormones and may have slightly elevated BTM levels. Patients with overt hyperthyroidism had higher BTM levels and anti-thyroid therapy induces a rapid decrease in the BTM levels. Patients with overt primary hyperparathyroidism have higher BTM levels, whereas those with asymptomatic and normocalcemic hyperparathyroidism usually have normal BTM levels. Hypoparathyroidism is characterized by slightly decreased BTM levels. Cushing's syndrome is characterized consistently by markedly decreased osteocalcin concentration, whereas data on other BTMs are discordant.

CONCLUSIONS

BTMs help us to better understand mechanisms of the impact of hormonal disorders and their treatment on bone metabolism. However, it is unknown whether BTMs may be used to monitor the effect of their treatments on bone in the clinical practice.

Bone Evaluation by High-Resolution Peripheral Quantitative Computed Tomography in Patients With Adrenal Incidentaloma

CONTEXT

Data regarding high-resolution peripheral quantitative computed tomography (HR-pQCT) in patients with adrenal incidentaloma (AI) are unknown.

PURPOSE

To evaluate the areal bone mineral density (aBMD), microstructure, and fractures in patients with nonfunctioning AI (NFAI) and autonomous cortisol secretion (ACS).

METHODS

We evaluated 45 patients with NFAI (1 mg dexamethasone suppression test [DST] ≤1.8 µg/dL) and 30 patients with ACS (1 mg DST 1.9-5.0 µg/dL). aBMD was measured using dual-energy X-ray absorptiometry; vertebral fracture by spine X-ray; and bone geometry, volumetric bone mineral density (vBMD), and microstructure by HR-pQCT.

RESULTS

Patients with ACS showed lower aBMD values at the spine, femoral neck, and radius 33% than those with NFAI. Osteoporosis was frequent in both groups: NFAI (64.9%) and ACS (75%). Parameters at the distal radius by HR-pQCT were decreased in patients with ACS compared to those with NFAI: trabecular vBMD (Tb.vBMD, P = 0.03), inner zone of the trabecular region (Inn.Tb.vBMD, P = 0.01), the bone volume/tissue volume ratio (BV/TV, P = 0.03) and trabecular thickness (P = 0.04). As consequence, a higher ratio of the outer zone of the trabecular region/inner zone vBMD (Meta/Inn.vBMD, P = 0.003) was observed. A correlation between the cortisol levels after 1 mg DST and Meta/Inn.vBMD ratio was found (r = 0.29; P = 0.01). The fracture frequency was 73.7% in patients with ACS vs 55.6% in patients with NFAI (P = 0.24).

CONCLUSION

Our findings point to an association between trabecular bone microarchitectural derangement at the distal radius and ACS. Our data suggest that AI have a negative impact on bone when assessed by HR-pQCT, probably associated to subclinical hypercortisolism.

The Impact of Mild Autonomous Cortisol Secretion on Bone Turnover Markers

CONTEXT

Several studies have reported increased risk of fragility fractures in patients with mild autonomous cortisol secretion (MACS), discordant to the degree of bone density deterioration.

OBJECTIVE

To evaluate the effect of MACS on bone metabolism in patients with adrenal adenomas.

DESIGN

Cross-sectional study with prospective enrollment, 2014-2019.

SETTING

Referral center.

PATIENTS

213 patients with adrenal adenomas: 22 Cushing syndrome (CS), 92 MACS and 99 nonfunctioning adrenal tumors (NFAT).

MAIN OUTCOME MEASURES

Osteocalcin, procollagen I intact N-terminal (PINP), C-terminal telopeptide (CTX), sclerostin.

RESULTS

Patients with CS demonstrated lower markers of bone formation compared with patients with MACS and NFAT (CS vs MACS vs NFAT: mean osteocalcin 14.8 vs 20.1 vs 21.3 ng/mL [P < 0.0001]; mean PINP 34.8 vs 48.7 vs 48.5 µg/L [P = 0.003]). Severity of cortisol excess was inversely associated with sclerostin (CS vs MACS vs NFAT: mean sclerostin 419 vs 538 vs 624 ng/L, [P < 0.0001]). In a multivariable model of age, sex, body mass index, cortisol, and bone turnover markers, sclerostin was a significant predictor of low bone mass in patients with MACS (OR 0.63 [CI 95%, 0.40-0.98] for each 100 ng/L of sclerostin increase).After adrenalectomy, osteocalcin, CTX, and sclerostin increased by a mean difference of 6.3 ng/mL, 0.12 ng/mL, and 171 pg/mL (P = 0.02 for all), respectively.

CONCLUSIONS

Lower sclerostin level in patients with MACS reflects a reduction in osteocyte function or number associated with exposure to chronic cortisol excess. Increase in bone turnover markers after adrenalectomy suggests restoration of favorable bone metabolism.

Evaluation of bone health in patients with adrenal tumors

PURPOSE OF REVIEW

Adrenal tumors occur in 5% of population with higher prevalence in elderly. Patients with adrenal tumors present with overt hormonal excess in up to 15% of cases, and mild autonomous cortisol secretion in 30-40% of cases. Overt Cushing syndrome, mild autonomous cortisol secretion, pheochromocytoma, and primary aldosteronism have been associated with higher cardiovascular morbidity and mortality. Increasing experimental and clinical evidence also suggests that adrenal hormone excess is detrimental to bone health. This review aims to discuss the effect of cortisol, aldosterone, and catecholamine excess on bone metabolism, secondary osteoporosis, and fragility fractures.

RECENT FINDINGS

Several studies have reported that patients with hormonally active adrenal tumors demonstrate increased prevalence of fragility fractures incongruous to bone density scan findings. The utility of dual absorptiometry X-ray (DXA) in diagnosing secondary osteoporosis is unclear in patients with cortisol, aldosterone, and catecholamine excess. Trabecular bone score and bone turn over markers could serve as potential diagnostic tools in assessment of severity of bone disease in patients with hormonally active adrenal tumors.

SUMMARY

Adrenalectomy is the mainstay of therapy in patients with overt hormone production. Appropriate case detection strategies to identify patients at risk of fragility fractures are needed in patients not treated with adrenalectomy, such as bilateral primary aldosteronism and mild autonomous cortisol secretion.

Bone Health in Patients with Cushing's Syndrome

INTRODUCTION

Osteoporosis is a well-recognized complication of Cushing's syndrome (CS). Data on bone health in patients with CS from south Asian countries, which are vitamin D deficient, are scarce.

AIMS

We assessed bone mineral density (BMD) in patients with CS in comparison to controls. We also looked into how BMD differs in different types of endogenous CS.

MATERIALS AND METHODS

Thirty-seven cases of CS and 48 matched controls were studied for clinical, biochemical, hormonal, and bone densitometry parameters.

RESULTS

BMD (both total lumbar spine (LS) and hip) as well as Z scores were significantly lower in CS patients as compared to controls. Neither LS nor hip BMD was significantly different among different etiological groups of CS. The difference in BMD was also not significant between eumenorrhoeic and oligo-/amenorrhoeic patients with CS.

CONCLUSION

Patients with CS are at increased risk of having fracture secondary to osteopenia and osteoporosis. There is no significant association of vitamin D and intact parathormone with low BMD in patients with CS.

Pituitary Diseases and Bone

Neuroendocrinology of bone is a new area of research based on the evidence that pituitary hormones may directly modulate bone remodeling and metabolism. Skeletal fragility associated with high risk of fractures is a common complication of several pituitary diseases such as hypopituitarism, Cushing disease, acromegaly, and hyperprolactinemia. As in other forms of secondary osteoporosis, pituitary diseases generally affect bone quality more than bone quantity, and fractures may occur even in the presence of normal or low-normal bone mineral density as measured by dual-energy X-ray absorptiometry, making difficult the prediction of fractures in these clinical settings. Treatment of pituitary hormone excess and deficiency generally improves skeletal health, although some patients remain at high risk of fractures, and treatment with bone-active drugs may become mandatory. The aim of this review is to discuss the physiological, pathophysiological, and clinical insights of bone involvement in pituitary diseases.

MECHANISMS IN ENDOCRINOLOGY: Endogenous subclinical hypercortisolism and bone: a clinical review

In recent years, the condition of subclinical hypercortisolism (SH) has become a topic of growing interest. This is due to the fact that SH prevalence is not negligible (0.8-2% in the general population) and that, although asymptomatic, this subtle cortisol excess is not harmless, being associated with an increased risk of complications, in particular of osteoporosis and fragility fractures. As specific symptoms of hypercortisolism are absent in SH, the SH diagnosis relies only on biochemical tests and it is a challenge for physicians. As a consequence, even the indications for the evaluation of bone involvement in SH patients are debatable and guidelines are not available. Finally, the relative importance of bone density, bone quality and glucocorticoid sensitivity in SH is a recent field of research. On the other hand, SH prevalence seems to be increased in osteoporotic patients, in whom a vertebral fracture may be the presenting symptom of an otherwise asymptomatic cortisol excess. Therefore, the issue of who and how to screen for SH among the osteoporotic patients is widely debated. The present review will summarize the available data regarding the bone turnover, bone mineral density, bone quality and risk of fracture in patients with endogenous SH. In addition, the role of the individual glucocorticoid sensitivity in SH-related bone damage and the problem of diagnosing and managing the bone consequences of SH will be reviewed. Finally, the issue of suspecting and screening for SH patients with apparent primary osteoporosis will be addressed.

Adrenal incidentaloma: evaluation and management

Adrenal incidentalomas are adrenal masses discovered incidental to imaging studies performed for reasons unrelated to adrenal pathology. Although most adrenal incidentalomas are non-functioning benign adenomas, their increasing prevalence presents diagnostic and therapeutic challenges. The assessment of adrenal incidentalomas is aimed at deciding whether or not the tumour should be surgically removed. Adrenalectomy is indicated for phaeochromocytoma, other symptomatic hormone-secreting tumours and those with a high risk of malignancy. Biochemical screening for tumour hypersecretion is mandatory in all adrenal incidentalomas, since hormone secreting tumours may be clinically silent. The diagnosis of phaeochromocytoma is of paramount importance because of its life-threatening complications. Non-functioning adrenal incidentalomas need assessment for risk of malignancy, and this is based on the size of the tumour and its imaging characteristics. An observational policy with periodic radiological and biochemical reassessment is pursued in patients with non-functioning incidentalomas with low malignancy risk. The duration and frequency of reassessment remains unclear, as the natural history of adrenal incidentalomas has yet to be clearly defined, and there is a lack of controlled studies comparing surgical intervention with observation. However, the possibility of acquiring autonomous hypersecretion or conversion to malignancy in an incidentaloma diagnosed to be a benign non-functioning lesion is very low, and most patients may be safely discharged after an initial follow-up period of 2 years.

Fracture risk assessment before and after resolution of endogenous hypercortisolism: is the FRAX® algorithm useful?

PURPOSE

Fracture risk data following curative treatment of Cushing's syndrome (CS) are scarce and the role of bisphosphonates in bone recovery after remission is controversial. We evaluated the effects of hypercortisolism remission in bone recovery in CS. Then, we assessed if the FRAX(®) algorithm calculated before the cure can predict fracture risk after cure.

METHODS

Thirty-six patients with CS were retrospectively investigated. Bone turnover markers, bone mineral density (BMD) at the lumbar spine (L1-L4) and left femur (both neck and total hip were considered), and fracture risk using FRAX(®) algorithm with femoral neck BMD were evaluated at diagnosis and after a median follow-up of 24 months (range 12-108 months) from hypercortisolism remission. Data about bone active therapy were analyzed.

RESULTS

Hypercortisolism remission was associated with the improvement of all densitometric parameters and with the reduction of fracture risk. The percentage change in BMD and the fracture risk were not significantly different in bisphosphonate-treated vs. untreated patients. During follow-up, three fractured patients at baseline exhibited a new vertebral fracture. A baseline 10-year probability of major osteoporotic fractures (FRAX(®) Major) of 17 % was able to predict the occurrence of a new vertebral fracture during follow-up after cure with 100 % sensitivity, 77 % specificity, 81 % positive predictive value and 100 % negative predictive value.

CONCLUSIONS

Osteoporosis and fracture risk may be reversible after curative treatment of CS, regardless of bisphosphonate therapy. We suggest applying the FRAX(®) algorithm to all active CS patients using a baseline FRAX(®) Major of 17 % as "intervention threshold".

Glucocorticoid-induced osteoporosis: lessons from Cushing's syndrome

Glucocorticoid-induced osteoporosis (GIO) is the most frequent form of secondary bone disorders. Most of our knowledge on its pathogenesis and treatment has been obtained by investigating patients treated with exogenous glucocorticoids. This review will focus on the bone disorder in endogenous Cushing's syndrome, updating recent advances in its pathophysiology, diagnostic aspects and the various predictors which are important in determining bone mineral density (BMD) and fracture risk. We now know strong evidence that beside BMD, bone microarchitecture, one of the most important elements of bone quality, is a key factor in determining fracture risk. Recently, two new methods (spinal deformity index and trabecular bone score) have been shown to be useful markers of bone microarchitecture in GIO. Investigations of GIO in endogenous Cushing's syndrome have also contributed to our understanding on its natural history and reversibility. Relying on recently published guidelines for management of exogenous GIO, a short list of suggestions is provided regarding the optimal diagnostic and therapeutic approach to patients with endogenous GIO.

Cortisol secretion, bone health, and bone loss: a cross-sectional and prospective study in normal non-osteoporotic women in the early postmenopausal period

OBJECTIVE

The aim of the study was to evaluate the relationship between cortisol secretion, bone health, and bone loss in a cohort of normal women in the early postmenopausal period.

METHODS

We measured lumbar and hip bone mineral density (BMD) by dual-energy X-ray absorptiometry (DXA) and heel ultrasound parameters in 82 healthy, nonosteoporotic (lumbar T-score ≥-2.0) women (median age 52.5 years, range 42-61). These women were examined in two sessions, 1 year apart, in the early postmenopausal period (onset of menopause between 6 and 60 months). Parameters of the hypothalamic-pituitary-adrenal (HPA) axis function were morning serum cortisol, morning and midnight salivary cortisol, 24-h urinary free cortisol (UFC), serum cortisol after 0.5 and 1 mg overnight dexamethasone, and DHEA-S.

RESULTS

In multiple regression analyses, the following significant inverse correlations were found: i) lumbar BMD and either 24-h UFC (P<0.005) or morning serum cortisol (P<0.05), ii) total femur and femoral neck BMD with morning serum cortisol (P=0.05 and P<0.05), and iii) heel ultrasound stiffness index and midnight salivary cortisol (P<0.005). The annual rate of change in lumbar and femoral BMD did not correlate with any of the above-mentioned hormonal variables. No difference was found in the parameters of HPA axis function in slow (loss of BMD <1%) vs fast (loss of BMD ≥3%) bone losers.

CONCLUSIONS

HPA axis may contribute to postmenopausal bone health, but differences in cortisol secretion do not influence the differential rate of bone loss between slow and fast bone losers in the early postmenopausal period, at least in healthy women.

Diagnostic performance of salivary cortisol and serum osteocalcin measurements in patients with overt and subclinical Cushing's syndrome

OBJECTIVE

The cut-off value for salivary cortisol measurement for the diagnosis of Cushing's syndrome (CS) may depend both on the severity of the disease and the composition of control group. Therefore, we examined the utility of midnight salivary cortisol measurements in patients who were evaluated for signs and symptoms of CS or because they had adrenal incidentalomas. Because serum osteocalcin (OC) is considered as a sensitive marker of hypercortisolism, we also investigated whether OC could have a role in the diagnosis of CS.

PATIENTS AND METHODS

Each of the 151 patients was included into one of the following groups: (A) overt CS (n=23), (B) subclinical CS (n=18), (C) inactive adrenal adenomas (n=40), (D) patients without HPA disturbances (n=70). Patients (C+D) were used as controls. Serum, salivary and urinary cortisol, and OC were measured by electrochemiluminescence immunoassay.

RESULTS

Group A had suppressed OC as compared to both group B and group (C+D). Serum and salivary cortisol concentrations showed strong negative correlations with OC in patients with overt CS. The areas under the curves of salivary and serum cortisol at 24:00 h (0.9790 and 0.9940, respectively) serum cortisol after low dose dexamethasone test (0.9930) and OC (0.9220) obtained from ROC analysis for the diagnosis of overt CS were not statistically different.

CONCLUSION

This study confirms the usefulness of midnight salivary cortisol measurements in the diagnosis of overt CS in the everyday endocrinological praxis. Our results suggest that OC may have a role in the diagnosis of overt CS.

Urinary deoxypyridinoline is a BMD-independent marker for prevalent vertebral fractures in postmenopausal women treated with glucocorticoid

SUMMARY

Urinary deoxypyridinoline (DPD) level was associated with prevalent vertebral fractures in glucocorticoid (GC)-treated postmenopausal women independently of lumbar spine bone mineral density (BMD).

INTRODUCTION

Bone metabolic indices are the potential predictors of bone fragility. However, their diagnostic efficiency for identifying the risk of GC-induced vertebral fractures is still unclear. We therefore evaluated whether bone metabolic indices would assess the risk of vertebral fractures in GC-treated women.

METHODS

One hundred seventy-five women treated with GC for more than 6 months were enrolled in this study.

RESULTS

Both premenopausal and postmenopausal women with vertebral fractures had significantly higher urinary DPD levels than those without vertebral fractures. When multivariable logistic regression analysis was performed with the presence of vertebral fractures as a dependent variable and each of DPD or osteocalcin level adjusted for age, weight, height, current and maximum doses of GC, duration of GC treatment, as well as lumbar spine BMD as an independent variable, DPD level was identified as a factor associated with the presence of vertebral fractures in postmenopausal women but not in premenopausal women.

CONCLUSION

Urinary DPD level was significantly associated with prevalent vertebral fractures in GC-treated postmenopausal women independently of lumbar spine BMD.

Beneficial metabolic effects of prompt surgical treatment in patients with an adrenal incidentaloma causing biochemical hypercortisolism

CONTEXT

In patients with adrenal incidentalomas, subclinical hypercortisolism (SH) is associated with an increased prevalence of the metabolic syndrome. The effect of surgical/conservative approach is debated.

OBJECTIVE

The objective of the study was to determine the effect of the surgical and conservative approaches on the metabolic syndrome in patients with adrenal incidentalomas.

DESIGN

This was a retrospective longitudinal study (18-48 months follow-up).

SETTING

The study was conducted on an in- and outpatient basis.

PATIENTS

One hundred eight patients with adrenal incidentalomas were studied for the presence of SH, which was diagnosed in the presence of more than two of the following: urinary free cortisol greater than 70 microg per 24 h (193 nmol per 24 h), cortisol after 1 mg dexamethasone suppression test greater than 3.0 microg/dl (83 nmol/liter), ACTH less than 10 pg/ml (2.2 pmol/liter).

INTERVENTIONS

Surgery was performed in 25 patients with SH (group TrSH+) and 30 without SH (group TrSH-), whereas the conservative approach was chosen by 16 patients with SH (group UntrSH+) and 37 without SH (group UntrSH-).

MAIN OUTCOME MEASURES

During the follow-up, the improvement/worsening of body weight, blood pressure, or glucose and cholesterol levels was defined in the presence of a greater than 5% weight decrease/increase and following the European Society of Cardiology or the Adult Treatment Panel III criteria, respectively.

RESULTS

In group TrSH+, weight, blood pressure, and glucose levels improved (32, 56, and 48%, respectively) more frequently than in group UntrSH+ (12.5%, P = 0.05; 0.0%, P < 0.0001; 0.0%, P = 0.001; and 0.0%, P = 0.0014, respectively). In group UntrSH+, blood pressure, glucose, and low-density lipoprotein levels worsened more frequently (50.0, 37.5, and 50.0%, respectively) than in group TrSH+ (0.0%, P < 0.0001; 0.0%, P = 0.001; and 20.0%, P = 0.05, respectively).

CONCLUSIONS

Regarding the various components of the metabolic syndrome, in patients with adrenal incidentalomas and SH, surgery is beneficial.

Bone turnover in patients with endogenous Cushing's syndrome before and after successful treatment

We investigated bone turnover and its restoration in a large number of patients in the active phase and after cure of endogenous Cushing's syndrome. Furthermore, the usefulness of serum osteocalcin and collagen breakdown products as potential markers of active Cushing's syndrome was also evaluated.

INTRODUCTION

Suppressed bone formation is one of the most characteristic features of Cushing's syndrome (CS). Despite numerous previous reports, many aspects of the disturbed bone metabolism of these patients are unexplored. In this study, we investigated the time course of bone marker changes after the cure of CS as well as correlations between bone markers and serum cortisol concentrations.

METHODS

Eighty-seven patients with CS were studied. Patients were followed up to 48 months after surgical cure. Serum osteocalcin (OC) and collagen breakdown products (CTX) were measured with immunochemiluminescence method and compared to the results of 161 healthy controls.

RESULTS

OC showed a negative, while CTX displayed a positive correlation with serum cortisol. Patients with diabetes mellitus and myopathy had significantly lower serum OC levels compared to those without these complications. The area under the curve of OC obtained by receiver-operating characteristics analysis for the discrimination of patients with CS from healthy controls was 0.9227. Postoperative OC increased rapidly from the first few days or weeks reaching its maximum at the sixth month and remained stable after the 24th postoperative month.

CONCLUSIONS

Our study demonstrated significant correlations between serum cortisol and both bone formation and resorption markers in the active phase of CS. We propose that OC may serve as a sensitive biologic marker of glucocorticoid activity in endogenous CS during its active phase and it may reflect the clinical cure of the disease.

Persistent increase of osteoprotegerin levels after cortisol normalization in patients with Cushing's syndrome

OBJECTIVE

Osteoprotegerin (OPG) has been identified as a decoy receptor that inhibits osteoclast differentiation and, more recently, as a paracrine regulator of vascular calcification. OPG is suppressed by glucocorticoids (GC); however, results from experimental and clinical studies are not univocal. The aim of this study was to evaluate OPG and bone metabolism in patients with Cushing's syndrome (CS) before and after cure.

DESIGN AND METHODS

Twenty-six patients with CS (all women, mean age: 39.1+/-11.9 years) and 24 age- and gonadal status-matched healthy women were studied for bone mineral density, bone metabolism, OPG, and receptor activator of nuclear factor-kB ligand at baseline. Twelve patients were also studied 6-18 months after surgery, with persistent normalization of cortisol levels.

RESULTS

OPG was significantly higher and osteocalcin (OC) was significantly lower in CS patients than in controls (OPG: 4.17+/-1.23 vs 2.95+/-0.79 pmol/l, P=0.00001; OC: 15.0+/-6.1 vs 18.8+/-6.8 ng/ml, P=0.04 in CS and controls respectively). After cure, we found no difference in OPG levels, despite a significant increase in OC levels (from 16.4+/-11 to 37.2+/-15 ng/ml, P=0.03).

CONCLUSION

Patients with CS showed increased OPG serum levels that remained unchanged after recovery, despite a restoration of bone formation. We speculate that high levels of OPG could reflect the persistent damage of the GCs on cardiovascular system.

Bone mineral density, prevalence of vertebral fractures, and bone quality in patients with adrenal incidentalomas with and without subclinical hypercortisolism: an Italian multicenter study

CONTEXT

In patients with adrenal incidentalomas and subclinical hypercortisolism (SH), the factors influencing bone and the prevalence of vertebral fractures are debated. Spinal deformity index (SDI), which reflects bone quality, has never been evaluated.

OBJECTIVE

The objective of the study was to investigate in these patients SDI and factors influencing the prevalence of fractures.

DESIGN

This was a retrospective, multicenter study.

SETTING

The study was conducted on an in- and outpatient basis.

PATIENTS

Patients included 287 adrenal incidentaloma patients (111 eugonadal males, 31 premenopausal, 145 postmenopausal females) and 194 controls (90 eugonadal males, 29 premenopausal, 75 postmenopausal females).

MAIN OUTCOME MEASURE

Bone mineral density (BMD) was measured by dual X-ray absorptiometry at lumbar spine and femoral neck. By radiograph each vertebra was assessed as intact (grade 0) or grade 1 (20-25%), 2 (25-40%), or 3 (>40%) deformity; SDI was calculated by summing the grade of deformity for each vertebra. SH was diagnosed in the presence of at least two of the following: urinary free cortisol greater than 70 microg per 24 h (193.1 nmol/liter), cortisol after 1-mg dexamethasone test greater than 3.0 microg/dl (>82.8 nmol/liter), ACTH less than 10 pg/ml (<2.2 pmol/liter).

RESULTS

BMD was significantly lower in SH+ than SH- patients and controls (lumbar spine -0.73 +/- 1.43, 0.17 +/- 1.33, 0.12 +/- 1.21, respectively; femoral neck -0.37 +/- 1.06, 0.07 +/- 1.09, 0.17 +/- 1.02). Patients with SH had higher fracture prevalence and SDI than those without SH and controls (70.6, 22.2, 21.8%, respectively, P < 0.0001; 0.31 +/- 0.68, 0.39 +/- 0.93, 1.35 +/- 1.27, respectively, P < 0.0001). Fractures and SDI were associated with SH (odds ratio 7.27, 95% confidence interval 3.94-13.41, P = 0.0001; beta = 0.352, t = 6.241, P = 0.0001, respectively) regardless of age, BMD, menopause, and gender.

CONCLUSION

SH is associated with low BMD, high fracture prevalence, and reduced bone quality as measured by SDI.

Affective Disorders, Bone Metabolism, and Osteoporosis

The nature of the relationship between affective disorders, bone mineral density (BMD), and bone metabolism is unresolved, although there is growing evidence that many medications used to treat affective disorders are associated with low BMD or alterations in neuroendocrine systems that influence bone turnover. The objective of this review is to describe the current evidence regarding the association of unipolar and bipolar depression with BMD and indicators of bone metabolism, and to explore potential mediating and confounding influences of those relationships. The majority of studies of unipolar depression and BMD indicate that depressive symptoms are associated with low BMD. In contrast, evidence regarding the relationship between bipolar depression and BMD is inconsistent. There is limited but suggestive evidence to support an association between affective disorders and some markers of bone turnover. Many medications used to treat affective disorders have effects on physiologic systems that influence bone metabolism, and these conditions are also associated with a range of health behaviors that can influence osteoporosis risk. Future research should focus on disentangling the pathways linking psychotropic medications and their clinical indications with BMD and fracture risk.

Eugonadal male patients with adrenal incidentalomas and subclinical hypercortisolism have increased rate of vertebral fractures

OBJECTIVE

Subclinical hypercortisolism (SH) is suggested to exert a deleterious effect on bone. This effect and the role of gonadal status in male subjects are not fully elucidated. We evaluated bone mineral density (BMD) and prevalence of vertebral fractures in eugonadal male subjects with adrenal incidentalomas (AI) and without SH.

DESIGN

This 12-month observational multicentre study was performed between January and December 2006 on inpatient basis in three referral Italian centres.

PATIENTS

Eighty-eight consecutive eugonadal male patients with AI and 90 matched control subjects were studied.

MEASUREMENTS

All subjects underwent the determination of BMD by dual-energy X-ray absorptiometry at lumbar spine (LS) and femoral neck (FN), and spinal radiograph. In AI patients SH was diagnosed in the presence of two of the following: urinary free cortisol > 193.1 nmol/l, cortisol after 1 mg dexamethasone suppression test > 82.8 nmol/l, ACTH levels < 2.2 pmol/l.

RESULTS

As compared to patients without SH (SH-, n = 66) and controls, patients with SH (SH+, n = 22) had lower BMD at LS (Z-score: SH+, -1.04 +/- 1.84; SH-, 0.19 +/- 1.34, Controls 0.20 +/- 1.28, P = 0.001 and FN (Z-score: SH+, -0.63 +/- 1.01; SH-, 0.01 +/- 1.01, Controls 0.26 +/- 1.06, P = 0.002) and higher prevalence of fractures (SH+, 72.7%; SH-, 21.2%, Controls 20.0%, P = 0.0001). Multivariable analyses showed that SH was associated to BMD at LS (beta = -0.378, P = 0.0001) and vertebral fractures (OR = 7.81, 95% CI 1.96-31.17, P = 0.004).

CONCLUSION

In eugonadal male patients with AI, SH is associated with low BMD and high prevalence of vertebral fractures.

The pituitary-adrenal axis and body composition

The activity of the pituitary-adrenal axis can profoundly impact on body composition. This is dramatically seen in Cushing's syndrome (CS) but changes in body composition are also implicated in depression and alcoholic pseudocushing's. The pathophysiological mechanisms underlying these changes remain poorly understood. Changes to body composition in CS include increased fat mass, decreased bone mass, thinning of the skin and reduced lean mass. Why these tissues are affected so dramatically is unclear. Additionally, the change in body composition between individuals varies considerably for reasons which are only now becoming evident. This paper reviews the phenotypic changes with altered pituitary-adrenal axis activity and discusses the mechanisms involved. The primary focus is on adipose, bone, muscle and skin since the most dramatic changes are seen in these tissues.

Skeletal differences in bone mineral area and content before and after cure of endogenous Cushing's syndrome

We examined bone densitometric data in a four-year follow-up period before and after the cure of CS. Plasma cortisol concentrations were similar, but the duration of estimated glucocorticoid excess was longer in patients with prevalent bone fractures compared to those without fractures. After therapy of CS, bone area, BMC and BMD increased significantly at the LS and femur during follow-up, but they decreased at the forearm, suggesting redistribution of bone minerals from the peripheral to the axial skeleton.

INTRODUCTION

Only a few studies report the changes in bone mineral density (BMD) after the cure of Cushing's syndrome (CS).

METHODS

Forty-one patients with Cushing's disease, 21 patients with adrenal CS and 6 patients with ectopic CS were prospectively enrolled. BMD, bone mineral content (BMC) and bone area were measured by DXA.

RESULTS

No significant correlations were found between serum cortisol concentrations and baseline bone densitometric data. After successful therapy of CS, bone area and BMD increased significantly at the lumbar spine (LS) and femur during follow-up, but they decreased at the forearm. The progressive increase in BMC at the LS had a significant negative correlation with the change of the BMC of radius in the first and second follow-up years. The change in the body mass index was an independent predictor for changes in BMC both at the LS and at the forearm at the second year of remission.

CONCLUSIONS

The regional differences and the time-dependent changes of BMC suggest that the source of marked increase in axial BMC after the cure of CS is, at least partly, due to the redistribution of bone minerals from the peripheral to the axial skeleton.

Glucocorticoid excess affects cortical bone geometry in premenopausal, but not postmenopausal, women

Glucocorticoid (GC) excess causes a great increase in fracture risk, but the effects of GC excess on cortical bone geometry are unknown. The present study was performed to examine the effects of GC excess on cortical bone geometry in both premenopausal and postmenopausal women. Ninety-six women receiving oral GC treatments and 10 women with Cushing syndrome (CS) were each compared to age-matched control subjects using peripheral quantitative computed tomography. Total area, periosteal circumference, and polar strength strain index (SSIp) were significantly lower in GC-treated patients compared with control subjects in premenopausal women but not in postmenopausal women. Moreover, cortical area and thickness as well as periosteal circumference and SSIp were significantly lower in patients with CS compared to controls in premenopausal women but not in postmenopausal women. Total area, cortical area, cortical thickness, periosteal circumference, as well as SSIp were significantly lower in GC-treated patients with vertebral fractures compared to those without vertebral fractures in premenopausal women but not in postmenopausal women. In conclusion, endogenous or exogenous GC excess affects bone geometry of forearms of premenopausal, but not postmenopausal, women. These effects of GC excess on bone geometry may provide a strength loss mechanism beneath increased vertebral fracture risk.

Skeletal involvement in adult patients with endogenous hypercortisolism

Overt endogenous glucocorticoid excess is a well-recognized cause of bone loss and osteoporotic fractures. Cortisol excess inhibits bone formation, increases bone resorption, impairs calcium absorption from the gut, and affects the secretion of several hormones (in particular gonadotropins and GH), cytokines, and growth factors, influencing bone metabolism. The glucocorticoid excess mainly affects trabecular bone, leading to vertebral fractures in up to 70% of patients. Osteoporotic fractures may be the presenting symptom of an otherwise silent glucocorticoid excess and can precede the diagnosis of hypercortisolism by up to 2 yr. The removal of glucocorticoid excess leads to a recovery of bone mass which is, however, often incomplete and delayed, although it reduces the risk of osteoporotic fractures. Bisphosphonate therapy has been suggested to be useful in maintaining bone mass in these patients. Subclinical hypercortisolism, a condition of impaired hypothalamic- adrenal-axis homeostasis without the classical signs and symptoms of glucocorticoid excess, is a recently defined entity, which has been shown to be associated to increased bone resorption, bone loss, and high prevalence of vertebral fractures regardless of gonadal status. However, data about the effect of this subtle glucocorticoid excess on bone are still scarce and conflicting. Moreover, it is not yet known whether removing the cause of subclinical hypercortisolism leads to a recovery of bone mass and reduces the risk of osteoporotic fractures. Finally, recent data suggest that subclinical hypercortisolism is a common and underrated finding in patients with established osteoporosis. In summary, it is crucial to evaluate the risk of osteoporosis and fractures in patients with glucocorticoid excess; on the other hand, it also seems advisable to screen for glucocorticoid excess patients with osteoporotic fractures without known secondary causes of osteoporosis.

High Cognitive Dietary Restraint Is Associated With Increased Cortisol Excretion in Postmenopausal Women

BACKGROUND

Cognitive dietary restraint (perceived ongoing effort to limit dietary intake to manage body weight) is common in women at all life stages. In young women, high dietary restraint has been associated with both increased excretion of cortisol (a stress hormone) and reduced bone mass. Whether this occurs in older women is unknown and is reported here for the first time.

METHODS

Postmenopausal women (49-75 years old) with high (n = 41) or low (n = 37) dietary restraint were compared to examine differences in urinary cortisol excretion, body composition assessed by dual-energy x-ray absorptiometry (bone mineral density, % body fat), dietary intake, anthropometrics, current exercise, and perceived stress.

RESULTS

Women with high or low dietary restraint did not differ in age, body mass index, waist-to-hip ratio, energy intake, perceived stress, current exercise, or measures of body composition. However, urinary cortisol excretion was higher in the high restraint group (248.2 +/- 61.7 nmol/d vs 204.3 +/- 66.1 nmol/d; p =.01). Multiple regression analysis indicated that restraint group (high or low) independently predicted 7.6% of the variance in cortisol excretion.

CONCLUSIONS

Postmenopausal women with high dietary restraint excrete more cortisol than do those with low restraint, suggesting that dietary restraint may be a source of stress. Although this was not associated with negative health effects in this sample, further investigation is warranted.

Restoration of the coupling process and normalization of bone mass following successful treatment of endogenous Cushing's syndrome: a prospective, long-term study

OBJECTIVE

Endogenous Cushing's syndrome (CS) is associated with bone loss and an increased risk of fractures. However, the long-term outcome of treatment on bone health has not been adequately clarified.

DESIGN

We followed 33 patients with active CS prospectively before and twice after treatment (mean follow-up 33 (n = 25) and 71 months (n = 18), respectively). The patients were compared to age-, sex- and body mass index (BMI)-matched controls, also followed longitudinally.

METHODS

Bone mineral indices (bone mineral density (BMD), bone mineral content (BMC) and bone area) were evaluated in the lumbar spine (LS), femoral neck (FN), and total body (TB) by dual-energy X-ray absorptiometry (DXA). Biochemical markers of bone turnover were assessed by serum levels of osteocalcin and C-terminal telopeptides of Type-1 collagen (CTX-1).

RESULTS

Mann-Whitney rank sum tests showed that BMD of the LS, FN and TB was reduced by 14.8% (P < 0.001), 15.7% (P < 0.001), and 9.2% (P < 0.001) in CS vs. controls at baseline, with markedly reduced serum osteocalcin (P = 0.014) and increased CTX-1 (P = 0.012) levels, but no correlation between markers. At first follow-up, BMD was increased in LS (7.9%, P < 0.001) and FN (3.5%, P = 0.003) compared to baseline. The time-dependent rise in BMD (LS (r = 0.59; P = 0.002) and FN (r = 0.52; P = 0.007); Spearman's rank correlation), in CS was paralleled by increased osteocalcin (275%, P < 0.001) and correlation between biochemical markers (r = 0.92, P < 0.001; Pearson's correlation). TB BMD did not increase significantly before the second follow-up, when BMD Z-scores were normalized in all three compartments.

CONCLUSION

Our observations demonstrate restoration of coupled bone remodeling and normalization of bone mineral density in all measured skeletal compartments of treated CS patients after prolonged recovery, first significant in predominantly trabecular bone (i.e. lumbar spine).

Results and long-term follow-up after unilateral adrenalectomy for ACTH-independent hypercortisolism in a series of fifty patients

Untreated hypercortisolism is a fatal state, causing functional disability. Even after successful treatment, clinical recovery is slower than the biochemical one, but data about clinical results, well-being and working capacity after surgery are scarce. This retrospective study aimed at evaluating the long-term outcome of patients after adrenalectomy for ACTH-independent hypercortisolism by the analysis of the clinical results, the survival and the subjective well-being status after surgery. Clinical data in 50 patients suffering from ACTH-independent hypercortisolism and treated between 1980 and 2000 by unilateral adrenalectomy were recorded. At a mean follow-up of 134 months, 3 patients were dead. All the surviving patients were asked to self estimate the physical and psychological recovery after surgery. After surgery, 100% of patients were biochemically cured. A clinical recovery was observed in most cases: obesity in 59.6% and hypertension in 57.5%. Bone mass density (BMD) significantly improved (+20%). The long-term mortality rate did not differ from normal population. Subjectively, a full recovery was confirmed by 95.6% of the surviving patients; it was correlated with the subjective feeling of physical recovery (95.6%) and regained working ability (93.3%). Despite of biochemical and clinical cure, no subjective improvement of the psychological conditions was observed in 26.7% of cases. At long-term follow-up, most objective symptoms of Cushing's syndrome (CS) disappear; subjective health and working ability are often regained, but a psychological impairment could persist in spite of a successful treatment.

Bone loss is more severe in primary adrenal than in pituitary-dependent Cushing's syndrome

Either exogenous or endogenous glucocorticoid excess is an established cause of osteoporosis and fractures. Glucocorticoids exert their negative effects on bone through mechanisms that are not yet completely elucidated; however, as many as 50% of patients with Cushing's syndrome suffer from osteoporosis. Bone loss induced by glucocorticoids is potentially reversible after resolution of glucocorticoid excess. It is presently unknown if Cushing's disease (CD) sustained by a pituitary ACTH-producing adenoma and adrenal-dependent Cushing's syndrome (ACS) sustained by an adrenocortical adenoma have a different potential of inducing osteopenia. The aim of the present study was to retrospectively analyze bone mineral density (BMD) in 26 patients with CD (4 men, 22 women, aged 14-79 years), 12 patients with ACS (4 men, 8 women, aged 32-79 years) and 38 healthy subjects carefully matched for sex, age and body mass index (BMI). Measurement of BMD was performed by dual-energy X-ray absorptiometry (DXA) using the Hologic QDR 4500 W instrument. Data were analyzed using absolute BMD values (g/cm2), T-score and Z-score referred to the manufacturer's normative data for the lumbar spine and to the NHANES III dataset for the hip. The patients with CD and ACS were comparable for age, BMI, estimated duration of disease, urinary free cortisol (UFC) levels, midnight serum cortisol and gonadal function. The analysis of variance demonstrated that lumbar bone densitometric parameters were significantly different among the three groups. They were more reduced in patients with ACS (BMD, 0.76+/-0.03 g/cm2; T-score, -2.78+/-0.28; Z-score, -2.25+/-0.30) while patients with CD (BMD, 0.87+/-0.02 g/cm2; T-score, -1.74+/-0.24; Z-score, -0.99+/-0.32) showed DXA values between the first group and controls (BMD, 1.02+/-0.02 g/cm2; T-score, -0.35+/-0.19; Z-score, 0.33+/-0.16). The difference in BMD at the spine remained statistically significant ( P=0.04) after adjustment for the non-significant differences in age, UFC and fat mass between CD and ACS. Conversely, femoral bone densitometric parameters were not significantly different between patients with ACS and CD, even if they were more reduced than in controls. In patients with ACS, we observed a reduction of DHEA-S levels, expressed as standard score ( Z-score) values referred to a group of 180 healthy subjects stratified by sex and different age groups (<40 years, between 40 and 60 years, >60 years) to circumvent the pronounced effect of gender and age on such hormone (ACS DHEA-S Z-score -0.88+/-1.4 versus CD DHEA-S Z-score 2.25+/-2.35, P=0.0001). DHEA-S Z-score values were significantly correlated with lumbar BMD ( r=0.41, P=0.02) and femoral BMD ( r=0.43, P=0.01). DHEA-S Z-score values were also significantly correlated with osteocalcin levels ( r=0.45, P=0.01). Our data suggest that bone loss is greater in ACS than in CD. A plausible explanation comes from the reduced DHEA-S level in ACS since DHEA-S has well known anabolic actions on bone. However, this hypothesis needs to be confirmed in large, prospective series of patients with Cushing's syndrome of different etiology.

Effect of single doses of dexamethasone and adrenocorticotrop hormone on serum bone markers in healthy subjects and in patients with adrenal incidentalomas and Cushing's syndrome

The aim of the present study was to explore whether short-term changes in glucocorticoid activity which occur during dynamic testing of the pituitary adrenal axis with dexamethasone, ACTH, or metyrapone could have an effect on serum osteocalcin (OC) and beta-crosslaps (beta-CTx) concentrations in healthy subjects, in patients with adrenal incidentalomas and in those with Cushing's syndrome. The study included 40 healthy subjects (35 women and 5 men, age range 18-69 yr), 49 patients with adrenal incidentalomas (34 women and 15 men, age range 19-77 yr) and 8 patients with Cushing's syndrome (5 cortisol-producing adenomas and 3 pituitary-dependent Cushing's syndrome, 3 women and 5 men, age range 19-70 yr). Serum OC and beta-CTx concentrations were determined with electrochemoluminescent immunoassays at midnight, after an overnight fast between 08:00 and 09:00 h, after an overnight dexamethasone test (1 mg, orally) and after a single dose of metyrapone (30 mg/kg, orally). In healthy subjects and in patients with adrenal incidentalomas, serum bone marker concentrations were also measured after a single dose of ACTH injection (Cortrosyn depot, 1 mg im). Patients with Cushing's syndrome, but not those with adrenal incidentalomas, showed significantly lower serum OC at midnight (18.5+/-12 ng/ml, mean+/-SD) and between 08:00 and 09:00 h (17.7+/-9.6 ng/ml) compared to corresponding values obtained in healthy subjects (24.5+/-7.0 and 28.3+/-12.2 ng/ml, respectively). Serum OC concentrations were significantly decreased after a single dose of 1-mg dexamethasone in healthy subjects (from 28.3+/-12.2 to 21.8+/-9.5 ng/ml) and in patients with adrenal incidentalomas (from 29.8+/-15.9 to 24.1+/-14.1 ng/ml), whereas serum OC concentrations remained unchanged in patients with Cushing's syndrome. In addition, serum OC concentrations were even more markedly decreased after a single dose of ACTH injection in both healthy subjects (12.5+/-4.6 ng/ml) and in patients with adrenal incidentalomas (12.2+/-6.5 ng/ml). By contrast, metyrapone administration failed to induce significant changes in OC levels. There were no significant differences in beta-CTx concentrations between the three groups or after drug treatments. Thus, serum OC levels should be interpreted with caution when obtained during testing of the pituitary-adrenal axis with dexamethasone or ACTH.

The clinically inapparent adrenal mass: update in diagnosis and management

Clinically inapparent adrenal masses are incidentally detected after imaging studies conducted for reasons other than the evaluation of the adrenal glands. They have frequently been referred to as adrenal incidentalomas. In preparation for a National Institutes of Health State-of-the-Science Conference on this topic, extensive literature research, including Medline, BIOSIS, and Embase between 1966 and July 2002, as well as references of published metaanalyses and selected review articles identified more than 5400 citations. Based on 699 articles that were retrieved for further examination, we provide a comprehensive update of the diagnostic and therapeutic approaches focusing on endocrine and radiological features as well as surgical options. In addition, we present recent developments in the discovery of tumor markers, endocrine testing for subclinical disease including autonomous glucocorticoid hypersecretion and silent pheochromocytoma, novel imaging techniques, and minimally invasive surgery. Based on the statements of the conference, the available literature, and ongoing studies, our aim is to provide practical recommendations for the management of this common entity and to highlight areas for future studies and research.

Evaluation of bone mineral density of the peripheral skeleton in pre- and postmenopausal women with newly diagnosed endogenous Cushing's syndrome

OBJECTIVE

Cushing's syndrome (CS) is a well recognized cause of bone loss. Although many previous studies have shown decreased bone mineral density (BMD) in the lumbar spina and proximal femur of patients with endogenous CS, so far, the data estimating BMD in their peripheral skeleton are sparse. The aim of the present study was to evaluate BMD in the forearm and heel of women with newly diagnosed CS and to investigate its possible correlation with serum osteocalcin (BGP) and 24-hour urinary free cortisol levels (UFC).

PATIENTS AND METHODS

BMD in the forearm (distal and ultradistal area) of 29 (13 premenopausal and 16 postmenopausal) women with newly diagnosed CS (18 with pituitary adenoma, 10 with adrenal tumor and 1 with ectopic) was measured by dual x-ray absorptiometry (DEXA) and was compared with BMD of 29 age, body mass index (BMI)- and oestrogen status matched healthy controls. Furthermore, in 18 (9 premenopausal and 9 postmenopausal) of the above patients (14 with pituitary adenoma, 5 with adrenal tumor and 1 with ectopic) broadband ultrasound attenuation (BUA) by quantitative ultrasound (QUS) of the heel was estimated and 18 age-, BMI- and oestrogen status matched healthy women served as controls. In all the patients serum BGP and UFC were measured at the time of diagnosis of CS.

RESULTS

Compared to their matched controls, BMD in the forearm and BUA values in the heel did not differ in the premenopausal women with CS, while in the postmenopausal group BMD in the forearm was decreased (P < 0.05) but not BUA. Apart from a weak negative correlation between serum BGP and BMD in the ultradistal site of the forearm in premenopausal women (P = 0.05), serum BGP and UFC did not show significant correlation with BMD or BUA.

CONCLUSIONS

BMD in the forearm is reduced only in postmenopausal women with newly diagnosed endogenous CS, while BUA in the heel is unaffected in both pre- and postmenopausal patients. Moreover, serum BGP and UFC do not seem to be relevant markers for assessing bone loss in the peripheral skeleton at the time of diagnosis of hypercortisolemia.

Cushing's syndrome and bone

Structural and functional impairment of skeletal system is a relevant cause of morbidity and disability in patients with Cushing's syndrome (CS). Approximately 30-50% of patients with CS experience fractures (particularly at the spinal level) consistent with the 50% incidence of osteoporosis. Growth failure, pubertal arrest are the hallmarks of CS in children and growing adolescents leading to reduced final adult height and peak bone mass. The decrease in osteoblast number and function, through different mechanisms, seems to play a central role in the bone loss in CS. Patients with CS have decreased serum levels of osteocalcin and alkaline phosphatase. Considering the preferential bone loss in the cancellous skeleton it is reasonable to measure BMD, possibly with Dual X-rays absorptiometry (DEXA) at lumbar spine, in all patients with CS. Patients cured from CS have increased prevalence of spine damage: therefore, a radiological follow-up of the skeleton should be included in the management of patients with CS not only during the active phase but also after cure. Glucocorticoid-induced osteoporosis is reversible. The recovery of bone loss in CS is slow, taking approximately ten years to become complete. In the meanwhile, patients with severe osteopenia are exposed to a high risk of fracture. Alendronate may induce a more rapid improvement in BMD than cortisol normalization alone and it could be useful in patients with persistent postsurgical hypercortisolism to prevent further bone loss. The decision to discontinue antiresorptive therapy should be based on clinical monitoring and DEXA measurements.