Vertebral Fractures Associated with Spinal Sagittal Imbalance and Quality of Life in Acromegaly: A Radiographic Study with EOS 2D/3D Technology

DXA-derived lumbar bone strain index corrected for kyphosis is associated with vertebral fractures and trabecular bone score in acromegaly

PURPOSE

The bone strain index (BSI) is a marker of bone deformation based on a finite element analysis inferred from dual X-ray absorptiometry (DXA) scans, that has been proposed as a predictor of fractures in osteoporosis (i.e., higher BSI indicates a lower bone's resistance to loads with consequent higher risk of fractures). We aimed to investigate the association between lumbar BSI and vertebral fractures (VFs) in acromegaly.

METHODS

Twenty-three patients with acromegaly (13 males, mean age 58 years; three with active disease) were evaluated for morphometric VFs, trabecular bone score (TBS), bone mineral density (BMD) and BSI at lumbar spine, the latter being corrected for the kyphosis as measured by low-dose X-ray imaging system (EOS®-2D/3D).

RESULTS

Lumbar BSI was significantly higher in patients with VFs as compared to those without fractures (2.90 ± 1.46 vs. 1.78 ± 0.33, p = 0.041). BSI was inversely associated with TBS (rho -0.44; p = 0.034), without significant associations with BMD (p = 0.151), age (p = 0.500), BMI (p = 0.957), serum IGF-I (p = 0.889), duration of active disease (p = 0.434) and sex (p = 0.563).

CONCLUSIONS

Lumbar BSI corrected for kyphosis could be proposed as integrated parameter of spine arthropathy and osteopathy in acromegaly helping the clinicians in identifying patients with skeletal fragility possibly predisposed to VFs.

The direct impact of pegvisomant on osteoblast functions and bone development

PURPOSE

Acromegaly is a chronic disease characterized by growth hormone (GH) hypersecretion, usually caused by a pituitary adenoma, resulting in elevated circulating levels of insulin-like growth factor type I (IGF-I). Pegvisomant (PEG), the GH-receptor (GHR) antagonist, is used in treating acromegaly to normalize IGF-I hypersecretion. Exposure to increased levels of GH and IGF-I can cause profound alterations in bone structure that are not completely reverted by treatment of GH hypersecretion. Indeed, there is evidence that drugs used for the treatment of acromegaly might induce direct effects on skeletal health regardless of biochemical control of acromegaly.

METHODS

We investigated, for the first time, the effect of PEG on cell proliferation, differentiation, and mineralization in the osteoblast cell lines MC3T3-E1 and hFOB 1.19 and its potential impact on bone development in zebrafish larvae.

RESULTS

We observed that PEG did not affect osteoblast proliferation, apoptosis, alkaline phosphatase (ALP) activity, and mineralization. After PEG treatment, the analysis of genes related to osteoblast differentiation showed no difference in Alp, Runx2, or Opg mRNA levels in MC3T3-E1 cells. GH significantly decreased cell apoptosis (- 30 ± 11%, p < 0.001) and increased STAT3 phosphorylation; these effects were suppressed by the addition of PEG in MC3T3-E1 cells. GH and PEG did not affect Igf-I, Igfbp2, and Igfbp4 mRNA levels in MC3T3-E1 cells. Finally, PEG did not affect bone development in zebrafish larvae at 5 days post-fertilization.

CONCLUSION

This study provides a first evidence of the impact of PEG on osteoblast functions both in vitro and in vivo. These findings may have clinically relevant implications for the management of skeletal health in subjects with acromegaly.

ACROMORFO study: gait analysis in a cohort of acromegalic patients

PURPOSE

In acromegaly, skeletal complications resulted to be associated with low quality of life (QoL) and high risk of falls. The aim of the present study was to perform a quantitative assessment of movement through gait analysis technique in patients with acromegaly.

STUDY POPULATION

Thirty-three acromegalic patients [9 with active disease (AD), 14 with controlled disease (CD) and 10 with disease remission (RD)] and 20 healthy subjects were enrolled for the study.

MEASUREMENTS

Kinetic and kinematic data were collected with 3D-gait analysis. Kinematic data were processed to compute the Gait Profile Score (GPS), a parameter that summarizes the overall deviation of kinematic gait data relative to unaffected population.

RESULTS

The acromegalic group showed longer stance phase duration (p < 0.0001) compared to controls. The GPS and several gait variable scores resulted to be statistically higher in the acromegalic group compared to healthy controls. GPS values were significantly higher in AD compared to CD (p < 0.05) and RD groups (p = 0.001). The AD group presented significantly higher values in terms of hip rotation and ankle dorsiflexion compared to CD and RD groups and with regard to the foot progression compared to RD. Interestingly, patients with RD exhibited a more physiological gait pattern.

CONCLUSION

Acromegalic patients showed quantitative alterations of gait pattern, suggesting instability and increased risk of falls. Arthropathy, along with its associated abnormal joint loading, proprioceptive impairment and hyperkyphosis could be contributing factors. Disease control and remission appear to improve postural balance. A better knowledge on walking performance in acromegaly would help to develop specific rehabilitation programmes to reduce falls' risk and improve QoL.

Conventional X-rays in the diagnosis and follow-up of vertebral fractures in patients with acromegaly: a real-life study

OBJECTIVES

To explore the role of conventional X-ray imaging in detecting vertebral fractures (VFs) in patients with acromegaly, both at diagnosis of disease and at the last clinical visit. The risk factors for VFs were also evaluated.

DESIGN AND METHODS

A retrospective cohort study was conducted on 60 consecutive patients with acromegaly, in a tertiary referral centre. Thoracolumbar spine radiography (X-spine) was performed at the last clinical visit during the follow-up in order to detect VFs. Routine chest radiograph, performed as a part of the general evaluation at diagnosis of acromegaly, were retrospectively analysed to screen for baseline VFs.

RESULTS

At diagnosis of acromegaly, chest X-ray revealed that 10 (17%) patients had VFs. Of the 50 patients without VFs at diagnosis of acromegaly, 33 (66%) remained unfractured at the last clinical visit (median [IQR] time, 144 [96-192] months after the diagnosis of acromegaly), whereas 17 (34%) had VFs. Overall, 22 patients (37%) had novel VFs detected on X-spine including five patients with previous VFs. Risk factor for incident VFs was the presence of hypogonadism at diagnosis of acromegaly (p = 0.016).

CONCLUSIONS

In acromegaly patients, conventional X-rays can detect vertebral fractures early at diagnosis of acromegaly. They can also reveal incident VFs, which may occur several years later even in patients without VFs at diagnosis, above all in relation to hypogonadism.

Cholecalciferol Use Is Associated With a Decreased Risk of Incident Morphometric Vertebral Fractures in Acromegaly

CONTEXT

Skeletal fragility is observed in 30% to 60% of acromegaly patients, representing an emerging complication of the disease that increases disability. Despite several studies having investigated the clinical and hormonal prognostic factors for the occurrence of vertebral fractures (VFs) in acromegaly, very few data are available on their prevention/treatment including the effect of vitamin D (VD) supplementation, which has been reported to have a fracture-protective effect in several studies in patients with osteoporosis.

OBJECTIVE

We aimed to investigate the role of cholecalciferol (D3) supplementation in the prevention of incident VFs (i-VFs) in acromegaly.

METHODS

A longitudinal, retrospective and multicenter study was performed on 61 acromegaly patients treated and untreated with D3 supplementation.

RESULTS

Twenty-six patients were treated with D3 supplementation according to clinical guidelines. The median D3 weekly dosage was 8500 IU (interquartile range [IQR]: 3900). The median duration of D3 supplementation was 94 months (IQR: 38). At last follow-up, i-VFs were diagnosed in 14 patients (23%). I-VFs were less prevalent in patients on D3 supplementation (14.3% of cases) compared to patients not treated with D3 (85.7%; P = .02). The final level of serum V25OH-D was significantly lower in patients who developed i-VFs (28.6 ng/mL, IQR: 4.1) compared to patients who did not develop i-VFs (34.2 ng/mL, IQR: 9.6; P = .05). The logistic regression confirmed the protective role of D3 supplementation on the occurrence of i-VFs (odds ratio: 0.16; 95% CI, 0.03-0.79; P = .01).

CONCLUSION

It is likely that D3 supplementation could lead to a reduction in i-VFs in acromegaly.

Acromegaly and the long-term fracture risk of the vertebra and hip: a national cohort study

In this national cohort study, the patients with acromegaly had significantly higher risks of clinical vertebral (HR 2.09 [1.58-2.78]) and hip (HR 2.52 [1.61-3.95]) fractures than the controls. The increased fracture risk in patients with acromegaly was time-dependent and was observed even during the early period of follow-up.

PURPOSE

Acromegaly is characterized by the overproduction of growth hormone (GH) and insulin-like growth factor-1 (IGF-1), both play important roles in regulating bone metabolism. We investigated the risk of vertebral and hip fractures in patients with acromegaly compared to age- and sex-matched controls.

METHODS

This nationwide population-based cohort study included 1,777 patients with acromegaly aged 40 years or older in 2006-2016 and 8,885 age- and sex-matched controls. A Cox proportional hazards model was used to estimate the adjusted hazard ratio (HR) [95% confidence interval].

RESULTS

The mean age was 54.3 years and 58.9% were female. For approximately 8.5 years of follow-up, the patients with acromegaly had significantly higher risks of clinical vertebral (HR 2.09 [1.58-2.78]) and hip (HR 2.52 [1.61-3.95]) fractures than the controls in the multivariate analyses. There were significant differences in the risks of clinical vertebral (P < 0.0001) and hip (P < 0.0001) fractures between the patients with acromegaly and the controls in the Kaplan-Meier survival analysis. The multivariable-adjusted HRs for clinical vertebral fractures comparing the patients with acromegaly with controls during and excluding the first 7 years of observation were 1.69 [1.15-2.49] and 2.70 [1.75-4.17], respectively. The HRs for hip fractures during and excluding the first 7 years of observation were 2.29 [1.25-4.18] and 3.36 [1.63-6.92], respectively.

CONCLUSIONS

The patients with acromegaly had a higher risk of hip fractures as well as clinical vertebral fractures than the controls. The increased fracture risk in patients with acromegaly was time-dependent and was observed even during the early period of follow-up.

Looking at the spine in controlled Acromegaly

Skeletal fragility with high risk of vertebral fractures (VFs) is an emerging complication of growth hormone (GH) hypersecretion. VFs often coexist with spine arthropathy and both clinical conditions negatively impact on quality of life of acromegalic subjects. Management of spine osteopathy and arthropathy in acromegaly could be challenging since both complications can persist or even progress after biochemical control of disease. This article analyzes the latest evidence about possible pathophysiological links between VFs and spine arthropathy in active and controlled acromegaly, as well as the diagnostic and therapeutic aspects concerning the holistic management of acromegalic osteo-arthropathy.

Vertebral Fractures in Acromegaly: A Systematic Review

INTRODUCTION

Acromegaly is characterized by a very particular alteration of bone microarchitecture, leading to increased vertebral fragility. However, due to inconsistent and insufficient evidence, no guidelines are available for the evaluation of this osteopathy.

METHODS

We performed a literature review of studies published between 1968 and January 2022 on the PubMed and SCOPUS databases using the terms "acromegaly" and "vertebral fractures". Twenty-four studies were found eligible for inclusion, published between June 2005 and November 2021. Included studies evaluated acromegaly patients, who were assessed for the presence of vertebral fractures. We excluded case reports, reviews, meta-analyses, letters to the editor, articles not written in English, and research performed on the same set of patients without significant differences in study design. Risk of bias was avoided by following the ROBIS risk of bias recommendations. We executed rigorous data collection, and the results are depicted as a narrative overview, but also, as statistical synthesis. Limitations of the evidence presented in the study include study heterogeneity, small sample sizes, and a small number of prospective studies with short follow-up.

FINDINGS

Data regarding vertebral fractures (VFs) in acromegaly and their influencing factors are variable. Twenty-four studies were included, nine out of which had a prospective design. The smallest group of acromegaly patients had 18 subjects and the largest included 248 patients. Prevalence ranges between 6.5% and 87.1%, although most studies agree that it is significantly higher than in controls. VFs also have a higher incidence (between 5.6% and 42%) and are more frequently multiple (between 46.15% and 71%). Evidence shows that disease activity and active disease duration are influencing factors for the prevalence and incidence of VFs. Nonetheless, hypogonadism does not seem to influence the frequency of VFs. While reports are conflicting regarding the use of bone mineral density in acromegaly, evidence seems to be slightly in favor of it not being associated with VFs. However, trabecular bone score is significantly lower in fractured patients, although no prospective studies are available.

INTERPRETATION

Vertebral fractures evaluation should be performed with regularity in all acromegalic patients, especially in the presence of active disease. Disease activity is an important determinant of vertebral fracture incidence and prevalence, although hypogonadism is less so. To clarify the predictive value of both BMD and TBS for vertebral fractures, additional, larger, prospective studies are necessary.

Impact of the diagnostic delay of acromegaly on bone health: data from a real life and long term follow-up experience

INTRODUCTION

Acromegaly is a chronic disease with systemic complications. Disease onset is insidious and consequently typically burdened by diagnostic delay. A longer diagnostic delay induces more frequently cardiovascular, respiratory, metabolic, neuropsychiatric and musculoskeletal comorbidities. No data are available on the effect of diagnostic delay on skeletal fragility. We aimed to evaluate the effect of diagnostic delay on the frequency of incident and prevalent of vertebral fractures (i-VFs and p-VFs) in a large cohort of acromegaly patients.

PATIENTS AND METHODS

A longitudinal, retrospective and multicenter study was conducted on 172 acromegaly patients.

RESULTS

Median diagnostic delay and duration of follow-up were respectively 10 years (IQR: 6) and 10 years (IQR: 8). P-VFs were observed in 18.6% and i-VFs occurred in 34.3% of patients. The median estimated diagnostic delay was longer in patients with i-VFs (median: 11 years, IQR: 3), in comparison to those without i-VFs (median: 8 years, IQR: 7; p = 0.02). Age at acromegaly diagnosis and at last follow-up were higher in patients with i-VFs, with respect to those without i-VFs. The age at acromegaly diagnosis was positively associated with the diagnostic delay (p < 0.001, r = 0.216). A longer history of active acromegaly was associated with a high frequency of i-VFs (p = 0.03). The logistic regression confirmed that patients with a diagnostic delay > 10 years had 1.5-folds increased risk of developing i-VFs (OR: 1.5; 95%CI: 1.1-2; p = 0.017).

CONCLUSION

Our data showed that the diagnostic delay in acromegaly has a significant impact on VF risk, further supporting the clinical relevance of an early acromegaly diagnosis.

Evaluating the Impact of Acromegaly on Quality of Life

Acromegaly has a substantial negative impact on quality of life (QoL). This review aims to discuss the impact of acromegaly on QoL from the clinical perspective as well as from the patient perspective. Furthermore, it aims to evaluate the use of patient-reported outcome measures (PROMs) in acromegaly and how PROMs aid decision-making. The recommendations presented in this review are based on recent clinical evidence on the impact of acromegaly on QoL combined with the authors' own clinical experience treating patients with acromegaly. We recommend that a patient-centered approach should be considered in treatment decisions, integrating conventional biochemical outcomes, tumor control, comorbidities, treatment complications, and PROMs, including QoL measures. This more integrated approach seems effective in treating comorbidities and improving patient-reported outcomes and is critical, as many patients do not achieve biochemical or tumor control and comorbidities, impairment in QoL may not remit even when full biochemical control is achieved.

Questionnaire and tools: clinical powerful instrument in acromegaly diagnosis and management

PURPOSE

Acromegaly is a rare chronic disease characterized by systemic comorbidity and reduced quality of life. Although achieving biochemical control has always been the primary goal of acromegaly therapy, recent evidence has shown that the traditional assessment does not adequately capture the complexity of symptoms and patients' perception. These findings result in the need to improve a fast decision-making process of the clinician, who should not only take into account biochemical-instrumental criteria, but also patients' symptoms. With the aim of supporting the clinician in the diagnostic and therapeutic decision-making process several disease-specific tools have been developed. The aim of this review is to provide a description of the acromegaly-specific tools, presenting their main features, their application in daily practice, and their efficacy and utility.

METHODS

A systematic search of Medline/PubMed, ISI-Web of Knowledge, and Google Scholar databases was done.

RESULTS

Specific instruments and questionnaires have recently been developed to assist clinicians in the assessment of acromegaly. These are either Patient-Reported Outcome tools, such as Acromegaly Quality of Life Questionnaire (AcroQoL) and Pain Assessment Acromegaly Symptom Questionnaire (PASQ), or Clinician-Reported Outcome tools, such as ACROSCORE, SAGIT^® and Acromegaly Disease Activity Tool (ACRODAT^®). Such tools are extremely flexible and, therefore, have been widely adopted by endocrinologists and other professionals, so much so that they have also been included as recommendations in the 2018 international guidelines.

CONCLUSION

Questionnaires and tools are useful in the management of acromegaly patients. They help clinicians evaluate patients' symptoms and could assist in the evaluation of disease activity.

Artificial intelligence-based radiomics on computed tomography of lumbar spine in subjects with fragility vertebral fractures

PURPOSE

There is emerging evidence that radiomics analyses can improve detection of skeletal fragility. In this cross-sectional study, we evaluated radiomics features (RFs) on computed tomography (CT) images of the lumbar spine in subjects with or without fragility vertebral fractures (VFs).

METHODS

Two-hundred-forty consecutive individuals (mean age 60.4 ± 15.4, 130 males) were evaluated by radiomics analyses on opportunistic lumbar spine CT. VFs were diagnosed in 58 subjects by morphometric approach on CT or XR-ray spine (D4-L4) images. DXA measurement of bone mineral density (BMD) was performed on 17 subjects with VFs.

RESULTS

Twenty RFs were used to develop the machine learning model reaching 0.839 and 0.789 of AUROC in the train and test datasets, respectively. After correction for age, VFs were significantly associated with RFs obtained from non-fractured vertebrae indicating altered trabecular microarchitecture, such as low-gray level zone emphasis (LGLZE) [odds ratio (OR) 1.675, 95% confidence interval (CI) 1.215-2.310], gray level non-uniformity (GLN) (OR 1.403, 95% CI 1.023-1.924) and neighboring gray-tone difference matrix (NGTDM) contrast (OR 0.692, 95% CI 0.493-0.971). Noteworthy, no significant differences in LGLZE (p = 0.94), GLN (p = 0.40) and NGDTM contrast (p = 0.54) were found between fractured subjects with BMD T score < - 2.5 SD and those in whom VFs developed in absence of densitometric diagnosis of osteoporosis.

CONCLUSIONS

Artificial intelligence-based analyses on spine CT images identified RFs associated with fragility VFs. Future studies are needed to test the predictive value of RFs on opportunistic CT scans in identifying subjects with primary and secondary osteoporosis at high risk of fracture.

High Prevalence of Vertebral Fractures Associated With Preoperative GH Levels in Patients With Recent Diagnosis of Acromegaly

CONTEXT

Osteopathy and morphometric vertebral fractures (VFs) are emerging complications in acromegaly. However, the prediction of VFs in this clinical setting is still a matter of uncertainty, and it is debated whether they are an early event in the natural history of the disease.

OBJECTIVE

We aimed to evaluate the prevalence and determinants of morphometric VFs in patients with recently diagnosed acromegaly.

METHODS

We enrolled 92 patients (43 men/49 women) on admission to the neurosurgery unit before transsphenoidal surgery, and compared them with control individuals without secondary forms of osteoporosis and pituitary disorders. We performed a VF assessment on preoperative chest x-ray images and collected biochemical, demographic, and clinical data.

RESULTS

We detected a significantly higher prevalence of VFs (33.7%) in patients with acromegaly than in controls (P = .001). Among the patients with acromegaly and VFs, 12 (38.7%) showed multiple VFs, and 5 (16.1%) showed moderate/severe VFs. Patients with VFs had higher random serum growth hormone (GH) levels than those with no VFs (P = .03), but there was no difference in insulin-like growth factor-1 (IGF-1) (P = .07) and IGF-1/Upper Normal Limit ratio (P = .08). Free 3,5,3'-triiodothyronine was slightly lower in patients with acromegaly and VFs than in those without VFs (P = .05). In multiple logistic analysis, GH was independently associated with risk for VFs (P = .003). The preoperative serum GH cutoff value that predicted VFs was 12 ng/mL.

CONCLUSION

For the first time, high prevalence of radiological VFs is reported in patients with recent diagnosis of acromegaly. Therefore, we can hypothesize that VFs are an early phenomenon of acromegaly and related to GH levels. VF assessment should be included in the workup at the diagnosis of acromegaly.

Skeletal disorders associated with the growth hormone-insulin-like growth factor 1 axis

Growth hormone (GH) and insulin-like growth factor 1 (IGF1) are important regulators of bone remodelling and metabolism and have an essential role in the achievement and maintenance of bone mass throughout life. Evidence from animal models and human diseases shows that both GH deficiency (GHD) and excess are associated with changes in bone remodelling and cause profound alterations in bone microstructure. The consequence is an increased risk of fractures in individuals with GHD or acromegaly, a condition of GH excess. In addition, functional perturbations of the GH-IGF1 axis, encountered in individuals with anorexia nervosa and during ageing, result in skeletal fragility and osteoporosis. The effect of interventions used to treat GHD and acromegaly on the skeleton is variable and dependent on the duration of the disease, the pre-existing skeletal state, coexistent hormone alterations (such as those occurring in hypogonadism) and length of therapy. This variability could also reflect the irreversibility of the skeletal structural defect occurring during alterations of the GH-IGF1 axis. Moreover, the effects of the treatment of GHD and acromegaly on locally produced IGF1 and IGF binding proteins are uncertain and in need of further study. This Review highlights the pathophysiological, clinical and therapeutic aspects of skeletal fragility associated with perturbations in the GH-IGF1 axis.

Direct effects of octreotide on osteoblast cell proliferation and function

PURPOSE

Octreotide (OCT) is a first-generation somatostatin analog (SSA) used in the treatment of acromegaly and neuroendocrine tumors (NETs). In both diseases, OCT interacts with somatostatin receptors 2 and 5 (SSTR2 and SSTR5), inhibiting hormone hypersecretion and cell proliferation. Skeletal health is an important clinical concern in acromegaly and NETs, since acromegalic osteopathy and NET bone metastasis occur in a remarkable number of patients. While OCT's effect on NET and pituitary cells has been extensively investigated, its direct action on bone cells remains unknown.

METHODS

Here, we investigated OCT direct effects on cell proliferation, differentiation, mineralization, and chemoattractant capacity of murine primary osteoblasts and osteoblast cell line MC3T3-E1.

RESULTS

OCT inhibited osteoblasts and MC3T3-E1 cell proliferation (- 30 ± 16%, and - 22 ± 4%, both p < 0.05 vs control) and increased MC3T3-E1 cell apoptosis (+ 76 ± 32%, p < 0.05 vs control). The anti-proliferative action of OCT was mediated by SSTR2 and SSTR5 in MC3T3-E1, while its pro-apoptotic effect was abrogated in SSTR2-silenced cells. The analysis of genes related to the early and late phases of osteoblast differentiation showed that OCT did not affect Alp, Runx2, Bglap, Spp1, and Sost levels in MC3T3-E1 cells. Similarly, OCT did not affect ALP activity, mineralization, and osteoclastogenic induction. Finally, Vegfa expression decreased in OCT-treated MC3T3-E1 cells and OCT inhibited pancreatic NET cell migration toward the osteoblast-conditioned medium.

CONCLUSION

This study provides the first evidence of the direct action of OCT on osteoblasts which may have clinically relevant implications for the management of skeletal health in subjects with acromegaly and metastatic NETs.

Vertebral Fractures Occur Despite Control of Acromegaly and Are Predicted by Cortical Volumetric Bone Mineral Density

CONTEXT

Recent studies suggest that cortical bone could also play a role in vertebral fracture (VF) development in acromegaly.

OBJECTIVE

Evaluate the occurrence of VFs and their relationship to dual energy x-ray absorptiometry-derived bone parameters.

METHODS

A single-center 2-year prospective study of acromegaly patients was conducted. Each subject had L1-4 spine, femoral neck and total hip (TH) areal BMD measured using DXA, and trabecular bone score (TBS) measurement performed. 3D Shaper™ was used to assess proximal femur trabecular and cortical volumetric (v)BMD, cortical surface (s)BMD, and cortical thickness (Cth). VF assessment was performed using the lateral spine imaging IVA™ mode with a Hologic Horizon® densitometer using a semiquantitative approach. Study outcomes were assessed at 2 time points: baseline and month 24.

RESULTS

70 acromegaly patients (34 M/36F; average 55.1 years) were studied, including 26 with active disease. In 13 patients, 9 with controlled disease, VF was observed. A decrease in TBS, sBMD, neck trabecular vBMD, TH, and neck cortical vBMD in VF compared with non-VF subjects was observed (P < .05). Multivariate analysis of fracture prediction showed TH cortical vBMD as the best fracture prediction parameter with area under the curve of 0.774. TBS was negatively associated with fasting plasma glucose and glycated hemoglobin (HBA1c) at each time point during the follow-up.

CONCLUSION

From the total number of 13 VF subjects, 9 were in the controlled disease group. The most sensitive and specific predictor of incident VF was TH cortical vBMD, suggesting that cortical bone is involved in fracture development.

Prevalence of vertebral fractures and serum sclerostin levels in acromegaly

OBJECTIVE

An increased prevalence of vertebral fractures (VFs) has been reported in previous studies. The aim of this study was to evaluate the association between bone mineral density (BMD), bone turnover markers, serum sclerostin levels, and vertebral fractures (VFs) in acromegaly patients. We also evaluated the effects of gonadal status, disease activity, treatment modality, age, sex, and body mass index (BMI) on skeletal endpoints.

DESIGN

Case-control study.

PATIENTS AND MEASUREMENTS

Seventy acromegaly patients (M/F:36/34, mean age 45.5 ± 11.9 years) and 70 controls (M/F:31/39; mean age 45.66 ± 11.9 years) were included. VFs, BMD, calcium metabolism, markers of bone turnover, and sclerostin levels were evaluated. BMD was measured by dual-energy X-ray absorptiometry (Hologic QDR 4500). Conventional lateral radiography of the spine was performed and the Genant method was used for the assessment of fractures of T4-L5 vertebrae.

RESULTS

The prevalence of vertebral fractures was higher in acromegalic patients as compared with the control group (72.9 vs. 20%; p < 0.001). Serum phosphate (P) levels (3.46 ± 0.59 mg/dl vs. 3.11 ± 0.44 mg/dl; p < 0.001) and b-cross laps (CTx) levels (0.47 µg/l, range 0.04-2.38 vs. 0.28 µg/l, range 0.11-0.80; p < 0.001) were significantly higher in acromegaly patients than control subjects. Serum sclerostin levels were similar between either acromegaly patients and control subjects or acromegaly patients with VF and without VF. In the means of treatment modality, VFs were more frequent in patients treated with adjuvant gamma knife radiosurgery (GKS) (p = 0.07). In the binary logistic regression analysis, the age of the acromegaly patients, the presence of hypogonadism, and GKS treatment were the factors significantly correlated with the occurrence of spinal fractures.

CONCLUSIONS

The prevalence of VFs in patients with acromegaly is higher than in control subjects. Since advanced age, the presence of hypogonadism and GKS treatment were the factors predicting VFs in acromegaly; radiological evaluations should be considered as an emerging tool especially in those patients. Although markers of bone turnover elevated in acromegaly, they were not useful for the prediction of fractures. Serum sclerostin levels showed no discrepancy between the two groups and further studies are required for assessment of sclerostin role in this form of secondary osteoporosis.

Update on vertebral fractures in pituitary diseases: from research to clinical practice

Derangement of pituitary hormone axes can induce changes in bone remodeling and metabolism with possible alterations in bone microarchitectural structure and increased susceptibility to fractures. Vertebral fractures (VFs), which are a hallmark of skeletal fragility, have been described in a very large number of patients with pituitary diseases. These fractures are clinically relevant, since they predispose to further fractures and may negatively impact on patients' quality of life. However, the management of skeletal fragility and VFs in the specific setting of pituitary diseases is a challenge, since the awareness for this disease is still low, prediction of VFs is uncertain, the diagnosis of VFs cannot be solely based on a clinical approach and also needs a radiological and morphometric approach, the risk of fractures may not be decreased via treatment of pituitary hormone disorders, and the effectiveness of bone-active drugs in this setting is not always evidence-based. This review is an update on skeletal fragility in patients with pituitary diseases, with a focus on clinical and therapeutic aspects concerning the management of VFs.