Steroid myopathy: some unresolved issues

Muscle ultrasound to identify prednisone-induced muscle damage in adults with nephrotic syndrome

Steroid myopathy is a non-inflammatory toxic myopathy that primarily affects the proximal muscles of the lower limbs. Due to its non-specific symptoms, it is often overshadowed by patients' underlying conditions. Prolonged or high-dosage use of glucocorticoids leads to a gradual decline in muscle mass. There are no tools available to identify the course of steroid myopathy before the patient displays substantial clinical symptoms. In this study, we investigated individuals with nephrotic syndrome receiving prednisone who underwent muscle ultrasound to obtain cross-sectional and longitudinal pictures of three major proximal muscles in the lower limbs: the vastus lateralis, tibialis anterior, and medial gastrocnemius muscles. Our findings revealed that grip strength was impaired in the prednisolone group, creatine kinase levels were reduced within the normal range; echo intensity of the vastus lateralis and medial gastrocnemius muscles was enhanced, the pennation angle was reduced, and the tibialis anterior muscle exhibited increased echo intensity and decreased thickness. The total dose of prednisone and the total duration of treatment impacted the degree of muscle damage. Our findings indicate that muscle ultrasound effectively monitors muscle structure changes in steroid myopathy. Combining clinical symptoms, serum creatine kinase levels, and grip strength improves the accuracy of muscle injury evaluation.

Autoimmune blistering diseases treated with glucocorticoids: An international study of steroid-induced myopathy

BACKGROUND

Patients with autoimmune blistering diseases (AIBDs) are often exposed to chronic glucocorticoid (GC) treatment with many side effects. Glucocorticoid-induced myopathy (GIM) is a well-established side effect, which particularly affects the proximal muscles. The Glucocorticoid Toxicity Index (GTI) is a validated global assessment tool which quantifies GC toxicity over time.

OBJECTIVES

This study marks the first study which analyses GIM in patients with AIBDs. The objectives of this study were to utilize the GTI to investigate the nature and prevalence of GIM in AIBD patients and explore potential risk factors.

METHODS

This international cohort study was conducted in blistering disease clinics across Australia, China, Greece, Iran, Japan, the Philippines, Turkey and the United States of America between February 2019 and July 2023. The GTI tool was completed by a medical practitioner at each patient visit. Data related to glucocorticoid toxicity were entered into the Steritas GTI 2.0 to generate an aggregate improvement and cumulative worsening score at each visit.

RESULTS

The study included 139 patients. There were 132 episodes of myopathy, and 47.5% of patients developed muscle weakness at some point during the study period. Cumulative GC dose correlated positively with myopathy risk, while average dose and treatment duration were not significant. Older age, male gender and obesity more than doubled the likelihood of developing GIM.

CONCLUSIONS

GIM is a common side effect experienced by AIBD patients on GC treatment. Muscle weakness is less likely to occur if cumulative GC dose is less than 0.75 mg/kg/day. Studies of exercise programs to mitigate myopathy and newer alternative treatments to reduce cumulative GC dose should be considered.

Glucocorticoid-Induced Myopathy: Typology, Pathogenesis, Diagnosis, and Treatment

Glucocorticoid-induced myopathy is a non-inflammatory toxic myopathy typified by proximal muscle weakness, muscle atrophy, fatigue, and easy fatigability. These vague symptoms coupled with underlying disorders may mask the signs of glucocorticoid-induced myopathy, leading to an underestimation of the disease's impact. This review briefly summarizes the classification, pathogenesis, and treatment options for glucocorticoid-induced muscle wasting. Additionally, we discuss current diagnostic measures in clinical research and routine care used for diagnosing and monitoring glucocorticoid-induced myopathy, which includes gait speed tests, muscle strength tests, hematologic tests, bioelectrical impedance analysis (BIA), dual-energy X-ray absorptiometry (DXA), computed tomography (CT), magnetic resonance imaging (MRI), electromyography, quantitative muscle ultrasound, histological examination, and genetic analysis. Continuous monitoring of patients receiving glucocorticoid therapy plays an important role in enabling early detection of glucocorticoid-induced myopathy, allowing physicians to modify treatment plans before significant clinical weakness arises.

Supplementation with β-hydroxy-β-methylbutyrate after resistance training in post-acute care patients with sarcopenia: A randomized, double-blind placebo-controlled trial

OBJECTIVES

This study aimed to evaluate the efficacy of adding β-hydroxy-β- methylbutyrate (HMB) supplementation to a 12-week exercise-based rehabilitation program in older adults with sarcopenia after discharge from a post-acute geriatric rehabilitation unit.

STUDY DESIGN

A randomized, double-blind, placebo-controlled trial with two parallel groups. The intervention group received 3 g/day of Ca-HMB and participated in a 12- week resistance training program (3 sessions/week). The control group received a placebo and followed the same training program.

MAIN OUTCOME MEASURES

The primary outcomes were the improvements of handgrip strength and physical performance assessed through the Short Physical Performance Battery (SPPB) and 4-meter gait speed; and handgrip strength. All variables were assessed at baseline, post-intervention, and 1-year follow-up.

RESULTS

After completing the 12-week exercise program, the intervention group showed significant improvements in SPPB-Balance (1.3, 95 %CI 0.3 to 2.4) and total SPPB score (2.2, 95 %CI 0.4 to 4.0). Intra-group analysis demonstrated gains in the SPPB-Chair Stand (0.7 points, 95 %CI 0.0 to 1.4) and total SPPB score (2.1 points, 95 %CI 0.3 to 3.9) in the intervention group. Improvements in handgrip strength were observed in women (3.7 kg, 95 %CI: 0.2 to 7.3) at the end of the intervention, and persisted at the 1-year follow-up.

CONCLUSIONS

Our findings suggest that the supplementation of 3 g/day of Ca-HMB with resistance exercise may significantly enhance muscle strength and physical performance among older women with sarcopenia after recent hospitalization. Given this study's limitations, the intervention's effectiveness cannot be drawn, and further studies are needed.

Management of Neurologic Complications in Patients with Brain and Spine Tumors

Patients with brain and spine tumors represent a distinct population with unique needs. We provide a practical review of neurologic care in this group with an emphasis on familiarizing the general neurologist to the nuances of neuro-oncologic supportive care. We review the management of cerebral edema, steroid dosing, and pertinent side effects. We discuss seizure management, including choice of anticonvulsants, putative antitumor effects, and important seizure mimics like drop attacks. We review the presentation and symptomatology of stroke-like migraine attack after radiation therapy (SMART syndrome). We describe the signs and symptoms that should prompt concern for metastatic spinal cord compression, as well as both acute and definitive treatment options. Finally, we discuss the underappreciated incidence of venous thromboembolic events, particularly in patients with gliomas, and review the data on management.

Oral corticosteroid use and sarcopenia-related traits in older people with chronic airway disease: a population-based study

Background

Sarcopenia is characterised by two major phenotypic components: low handgrip strength (HGS) and appendicular skeletal muscle index (ASMI). Oral corticosteroid (OCS) use is an important medication for acute respiratory exacerbations in patients with COPD and asthma. However, the association of OCS and sarcopenia components in older people is largely unexplored. The aim of this study was to examine the association between OCS use and HGS or ASMI in the general population and explore interactions with chronic airway diseases.

Methods

From the population-based Rotterdam Study, 5054 participants (age 69.0±8.8 years; 56% females) were included in the cross-sectional analysis and 1324 in the longitudinal analysis. Associations between OCS and muscle strength and mass were analysed using linear regression models adjusted for age, sex, fat %, height, kidney function, smoking and comorbidities.

Results

At baseline, ever-OCS users had lower handgrip strength (β= -0.48, 95% CI -0.84- -0.12) than never-OCS users, with cumulative frequency (≥10 OCS prescriptions)-dependent effects (β= -1.25, 95% CI -2.16- -0.33). COPD ever-OCS users, but not asthma, had lower handgrip strength (β= -0.98, 95% CI -1.91- -0.06) and lower lean mass (β= -0.14, 95% CI -0.27- -0.01) than never-OCS users. After 5.6 years of follow-up in those free of sarcopenia traits at baseline, COPD ever-OCS users developed lower handgrip strength (β= -1.64, 95% CI -2.87- -0.40) with frequency (β= -3.64, 95% CI -6.57- -0.72) and duration (β= -1.51, 95% CI -2.87- -0.15) association compared to never-OCS users.

Conclusions

OCS use is associated with a decline in handgrip strength in people with COPD in a cumulative frequency and duration-dependent manner. Routine muscle examination may be necessary for patients with COPD.

Musculoskeletal involvement: COVID-19 and post COVID 19

The worldwide pandemic of coronavirus disease 2019 (COVID-19) was known to predominantly affect the lungs, but it was realized that COVID-19 had a large variety of clinical involvement. Cardiovascular, gastrointestinal, neurological, and musculoskeletal systems are involved by direct or indirect mechanisms with various manifestations. The musculoskeletal involvement can manifest during COVID-19 infection, due to medications used for the treatment of COVID-19, and in the post/long COVID-19 syndrome. The major symptoms are fatigue, myalgia/arthralgia, back pain, low back pain, and chest pain. During the last two years, musculoskeletal involvement increased, but no clear consensus was obtained about the pathogenesis. However, there is valuable data that supports the hypothesis of angiotensinconverting enzyme 2, inflammation, hypoxia, and muscle catabolism. Additionally, medications that were used for treatment also have musculoskeletal adverse effects, such as corticosteroid-induced myopathy and osteoporosis. Therefore, while deciding the drugs, priorities and benefits should be taken into consideration. Symptoms that begin three months from the onset of the COVID-19 infection, continue for at least two months, and cannot be explained by another diagnosis is accepted as post/long COVID-19 syndrome. Prior symptoms may persist and fluctuate, or new symptoms may manifest. In addition, there must be at least one symptom of infection. Most common musculoskeletal symptoms are myalgia, arthralgia, fatigue, back pain, muscle weakness, sarcopenia, impaired exercise capacity, and physical performance. In addition, the female sex, obesity, elderly patients, hospitalization, prolonged immobility, having mechanical ventilation, not having vaccination, and comorbid disorders can be accepted as clinical predictors for post/long COVID-19 syndrome. Musculoskeletal pain is also a major problem and tends to be in chronic form. There is no consensus on the mechanism, but inflammation and angiotensin-converting enzyme 2 seem to play an important role. Localized and generalized pain may occur after COVID-19, and general pain is at least as common as localized pain. An accurate diagnosis allows physicians to initiate pain management and proper rehabilitation programs.

Irisin and Bone in Sickness and in Health: A Narrative Review of the Literature

Irisin is a hormone-like myokine produced by the skeletal muscle in response to exercise. Upon its release into the circulation, it is involved in the browning process and thermogenesis, but recent evidence indicates that this myokine could also regulate the functions of osteoblasts, osteoclasts, and osteocytes. Most human studies have reported that serum irisin levels decrease with age and in conditions involving bone diseases, including both primary and secondary osteoporosis. However, it should be emphasized that recent findings have called into question the importance of circulating irisin, as well as the validity and reproducibility of current methods of irisin measurement. In this review, we summarize data pertaining to the role of irisin in the bone homeostasis of healthy children and adults, as well as in the context of primary and secondary osteoporosis. Additional research is required to address methodological issues, and functional studies are required to clarify whether muscle and bone damage per se affect circulating levels of irisin or whether the modulation of this myokine is caused by the inherent mechanisms of underlying diseases, such as genetic or inflammatory causes. These investigations would shed further light on the effects of irisin on bone homeostasis and bone disease.

Role of Glucocorticoid Signaling and HDAC4 Activation in Diaphragm and Gastrocnemius Proteolytic Activity in Septic Rats

Sepsis increases glucocorticoid and decreases IGF-1, leading to skeletal muscle wasting and cachexia. Muscle atrophy mainly takes place in locomotor muscles rather than in respiratory ones. Our study aimed to elucidate the mechanism responsible for this difference in muscle proteolysis, focusing on local inflammation and IGF-1 as well as on their glucocorticoid response and HDAC4-myogenin activation. Sepsis was induced in adult male rats by lipopolysaccharide (LPS) injection (10 mg/kg), and 24 h afterwards, rats were euthanized. LPS increased TNFα and IL-10 expression in both muscles studied, the diaphragm and gastrocnemius, whereas IL-6 and SOCS3 mRNA increased only in diaphragm. In comparison with gastrocnemius, diaphragm showed a lower increase in proteolytic marker expression (atrogin-1 and LC3b) and in LC3b protein lipidation after LPS administration. LPS increased the expression of glucocorticoid induced factors, KLF15 and REDD1, and decreased that of IGF-1 in gastrocnemius but not in the diaphragm. In addition, an increase in HDAC4 and myogenin expression was induced by LPS in gastrocnemius, but not in the diaphragm. In conclusion, the lower activation of both glucocorticoid signaling and HDAC4-myogenin pathways by sepsis can be one of the causes of lower sepsis-induced proteolysis in the diaphragm compared to gastrocnemius.

Irisin and Secondary Osteoporosis in Humans

Irisin is a peptide secreted by skeletal muscle following exercise that plays an important role in bone metabolism. Numerous experiments in vitro and in mouse models have shown that the administration of recombinant irisin promotes osteogenesis, protects osteocytes from dexamethasone-induced apoptosis, prevents disuse-induced loss of bone and muscle mass, and accelerates fracture healing. Although some aspects still need to be elucidated, such as the dose- and frequency-dependent effects of irisin in cell cultures and mouse models, ample clinical evidence is emerging to support its physiological relevance on bone in humans. A reduction in serum irisin levels, associated with an increased risk of osteoporosis and bone fractures, was observed in postmenopausal women and in both men and women during aging, Recently, cohort studies of subjects with secondary osteoporosis showed that these patients have lower circulating levels of irisin, suggesting that this myokine could be a novel marker to monitor bone quality in this disease. Although there are still few studies, this review discusses the emerging data that are highlighting the involvement of irisin in some diseases that cause secondary osteoporosis.

Quantitative assessment of muscle mass and gene expression analysis in dogs with glucocorticoid-induced muscle atrophy

The present study aimed to quantitatively evaluate muscle mass and gene expression in dogs with glucocorticoid-induced muscle atrophy. Five healthy beagles received oral prednisolone for 4 weeks (1 mg/kg/day), and muscle mass was then evaluated via computed tomography. Histological and gene expression analyses were performed using biopsy samples from the biceps femoris before and after prednisolone administration. The cross-sectional area of the third lumbar paraspinal and mid-femoral muscles significantly decreased after glucocorticoid administration (from 27.5 ± 1.9 to 22.6 ± 2.0 cm² and from 55.1 ± 4.7 to 50.7 ± 4.1 cm², respectively; P<0.01). The fast- and slow-twitch muscle fibers were both atrophied (from 2,779 ± 369 to 1,581 ± 207 μm² and from 2,871 ± 211 to 1,971 ± 169 μm², respectively; P<0.05). The expression of the growth factor receptor-bound protein 10 (GRB10) significantly increased after prednisolone administration (P<0.05). Because GRB10 suppresses insulin signaling and the subsequent mammalian target of rapamycin complex 1 activity, increased expression of GRB10 may have resulted in a decrease in protein anabolism. Taken together, 1 mg/kg/day oral prednisolone for 4 weeks induced significant muscle atrophy in dogs, and GRB10 might participate in the pathology of glucocorticoid-induced muscle atrophy in canines.

Improvement in the Physical Function and Quality of Life through Exercise and Physical Activity Intervention Using a Smartphone after Allogeneic Hematopoietic Cell Transplantation: A Case Report

PURPOSE

Physical activity (PA) interventions positively affect the physical function (PF) in patients with advanced cancer. However, patients must remain motivated during the intervention. We report a case wherein a smartphone application for PA intervention was useful in motivating the patient to improve adherence.

METHODS

A 40-year-old woman underwent an allogeneic hematopoietic cell transplantation (allo-HCT) for an advanced extranodal natural killer/T-cell lymphoma. On day 6, she developed the posterior reversible encephalopathy syndrome. She was managed in the intensive care unit for 3 days, and her PF declined markedly. We initiated a smartphone-based PA intervention from day 35. She was instructed to maintain a PA diary for self-monitoring of the daily steps and to set a new step-count goal every week.

RESULTS

The PA and PF improved within a short period thereafter. However, she developed severe acute graft-versus-host disease and was administered with high-dose systemic corticosteroids from day 49. The PA, PF, and quality of life (QOL) decreased again. The intervention was continued for 5 months with a high adherence. The PA, PF, and QOL improved gradually. She resumed independent activities of daily living and was discharged on day 202.

CONCLUSION

Smartphone-based PA intervention may be effective against post-allo-HCT physical dysfunction.

Clinical features and diagnostic tools in idiopathic inflammatory myopathies

Idiopathic inflammatory myopathies (IIMs) are rare autoimmune disorders affecting primarily muscles, but other organs can be involved. This review describes the clinical features, diagnosis and treatment for IIMs, namely polymyositis (PM), dermatomyositis (DM), sporadic inclusion body myositis (sIBM), immune-mediated necrotizing myopathy (IMNM), and myositis associated with antisynthetase syndrome (ASS). The diagnostic approach has been updated recently based on the discovery of circulating autoantibodies, which has enhanced the management of patients. Currently, validated classification criteria for IIMs allow clinical studies with well-defined sets of patients but diagnostic criteria to guide the care of individual patients in routine clinical practice are still missing. This review analyzes the clinical manifestations and laboratory findings of IIMs, discusses the efficiency of modern and standard methods employed in their workup, and delineates optimal practice for clinical care. Α multidisciplinary diagnostic approach that combines clinical, neurologic and rheumatologic examination, evaluation of electrophysiologic and morphologic muscle characteristics, and assessment of autoantibody immunoassays has been determined to be the preferred approach for effective management of patients with suspected IIMs.

Diurnal Salivary Cortisol in Sarcopenic Postmenopausal Women: The OsteoLaus Cohort

Sarcopenia, similar to hypercortisolism, is characterized by loss of muscle mass and strength. Cortisol circadian rhythm changes with aging (blunted late-day nadir values) were suggested to contribute to this decline. We aimed to explore the relationship between diurnal salivary cortisol values and sarcopenia diagnosis and its components in postmenopausal women. This is a cross-sectional study within the OsteoLaus population-based cohort in Lausanne (Switzerland). Participants had a body composition assessment by dual X-ray absorptiometry (DXA), a grip strength (GS) measure, and salivary cortisol measures (at awakening, 30 min thereafter, 11 AM (sc-11AM) and 8 PM (sc-8PM)). Associations between salivary cortisol and sarcopenia diagnosed by six different criteria (based on appendicular lean mass (ALM) assessed by DXA, and muscle strength by GS), and its components, were analyzed. 471 women aged > 50 years (63.0 ± 7.5) were included. Various definitions identified different participants as sarcopenic, who consistently presented higher salivary cortisol at 11 AM and/or 8 PM. There were no associations between salivary cortisol levels and ALM measures, either absolute or after correction to height squared (ALM index) or body mass index. GS was inversely correlated to sc-11AM (r = - 0.153, p < 0.001) and sc-8PM (r = - 0.118, p = 0.002). Each 10 nmol/l increase of sc-11AM, respectively sc-8PM, was associated with a GS decrease of 1.758 (SE 0.472) kg, respectively 2.929 (SE 1.115) kg. In postmenopausal women, sarcopenia is associated with higher salivary cortisol levels at 11 AM and 8 PM. An increase of daily free cortisol levels in the physiological range could participate to sarcopenia development by decreasing muscle function in postmenopausal women.

Cardiopulmonary exercise testing in COVID-19 patients at 3 months follow-up

Background

Long-term effects of Coronavirus Disease of 2019 (COVID-19) are of utmost relevance.

We aimed to determine: 1) the functional capacity of COVID-19 survivors by cardiopulmonary exercise testing (CPET); 2) the characteristics associated with cardiopulmonary exercise testing (CPET) performance; 3) the safety and tolerability of CPET.

Methods

We prospectively enrolled consecutive patients with laboratory-confirmed COVID-19 from Azienda Sanitaria Locale 3, Genoa. Three months after hospital discharge a complete clinical evaluation, trans-thoracic echocardiography, CPET, pulmonary function tests, and dominant leg extension (DLE) maximal strength measurement were performed.

Results

From the 225 patients discharged alive from March to November 2020, we excluded 12 incomplete/missing cases and 13 unable to perform CPET, leading to a final cohort of 200. Median percent-predicted peak oxygen uptake (%pVO2) was 88% (78.3–103.1).

Ninety-nine (49.5%) patients had %pVO2 below, whereas 101 (50.5%) above the 85% predicted value.

Among the 99 patients with reduced %pVO2, 61 (61%) had a normal anaerobic threshold: of these, 9(14.8%) had respiratory, 21(34.4%) cardiac, and 31(50.8%) non-cardiopulmonary reasons for exercise limitation. Inerestingly, 80% of patients experienced at least one disabling symtpom, not related to %pVO2 or functional capacity.

Multivariate linear regression showed percent-predicted forced expiratory volume in one-second(β = 5.29,p = 0.023), percent-predicted diffusing capacity of lungs for carbon monoxide(β = 6.31,p = 0.001), and DLE maximal strength(β = 14.09,p = 0.008) to be independently associated with pVO2.

No adverse event was reported during or after CPET, and no involved health professional developed COVID-19.

Conclusions

At three months after discharge, about 1/3rd of COVID-19 survivors show functional limitations, mainly explained by muscular impairment, calling for future research to identify patients at higher risk of long-term effects that may benefit from careful surveillance and targeted rehabilitation.

How we can mitigate the side effects associated with systemic glucocorticoid after allogeneic hematopoietic cell transplantation

Allogeneic hematopoietic cell transplantation (allo-HCT) is a potentially curative treatment for patients with a hematologic disease. Although the clinical outcomes after allo-HCT have significantly improved during the last few decades, graft-versus-host disease (GVHD) is still a major cause of post-HCT morbidity and mortality. Systemic glucocorticoids (GC) remain an integral part of treatment in patients with GVHD including both acute and chronic GVHD. Although it is well-known that usage of systemic GC is associated with various side effects, the short- and long-term effects of GCs in the HCT setting are not well-characterized due to limited published data. In order to clarify this issue, we summarize the information on side effects associated with GCs, focusing specifically on the sequelae of these agents in the early post-HCT period. In instances where limited data are available, we included data from other fields such as autoimmune diseases, given the potential parallels between autoimmune conditions and GVHD.

Glucocorticoid-induced myopathy in people with asthma: a systematic review

OBJECTIVES

To review the current literature on the evidence and the underlying characteristics of glucocorticoids (type, dosage, and duration) associated with myopathy in asthma.

DATA SOURCES

Four electronic databases were searched to October 19, 2020.

STUDY SELECTION

Inclusion criteria: adults or adolescents with asthma, taking systemic glucocorticoids, and measures of muscle impairments.

RESULTS

Nine studies met the eligibility criteria. The methodologic quality of most studies was fair or good. Two studies reported significantly lower inspiratory muscle function in outpatients taking daily oral glucocorticoids (≥10 mg), but one study reported no such difference. No differences was found in limb muscle strength in one study. Only 11-36% patients with acute exacerbation taking glucocorticoids intravenously suffered from limb muscle weakness during/after critical care admissions. Two studies reported significant associations between dosage of oral glucocorticoid use and inspiratory and limb muscle function, whereas seven studies did not find any significant correlations among the characteristics of systemic glucocorticoids and myopathy. Two studies comparing people with non-glucocorticoid dependent asthma taking inhaled glucocorticoid and healthy people did not find any significant differences in their inspiratory muscle strength and endurance.

CONCLUSIONS

There were limited studies and inconsistent results on glucocorticoid-induced myopathy in people with asthma, and its association with the characteristics of glucocorticoids use. We recommended future studies should use a commonly accepted operational definition of myopathy, utilize a cohort study design, measure the cumulative dosage of glucocorticoids, and integrate possible confounding factors in the analysis.

Persisting Muscle Dysfunction in Cushing's Syndrome Despite Biochemical Remission

CONTEXT

Glucocorticoid-induced myopathy is a characteristic symptom of endogenous Cushing's syndrome (CS). Its long-term outcome is largely unknown.

OBJECTIVE

To evaluate long-term muscle function following the remission of endogenous CS.

STUDY DESIGN

Observational longitudinal cohort study.

SETTING

Tertiary care hospitals and a specialized outpatient clinic.

PATIENTS

As part of the prospective multicenter German Cushing's Registry, we assessed muscle strength in patients with overt endogenous CS. We studied the patients at the time of diagnosis (n = 88), after 6 months (n = 69), and thereafter annually, following surgical remission over a period of up to 4 years (1 year: n = 55; 2 years: n = 34; 3 years: n = 29; 4 years: n = 22). Muscle function was evaluated by hand grip strength and by chair rising test.

RESULTS

Grip strength was decreased to 83% of normal controls (100%) at the time of diagnosis. It further decreased to 71% after 6 months in remission (P ≤ 0.001) and showed no improvement during further follow-up compared with baseline. Chair rising test performance improved initially (8 seconds at baseline vs 7 seconds after 6 months, P = 0.004) but remained at this reduced level thereafter (7 seconds after 3 years vs 5 seconds in controls, P = 0.038). In multivariate analysis, we identified, as predictors for long-term muscle dysfunction, age, waist-to-hip ratio, and hemoglobin A1c at baseline. Furthermore, muscle strength during follow-up was strongly correlated with quality of life.

CONCLUSION

This study shows that CS-associated myopathy does not spontaneously resolve during remission. This calls for action to identify effective interventions to improve muscle dysfunction in this setting.

Cushing's syndrome: Overview of clinical presentation, diagnostic tools and complications

Cushing's syndrome (CS) is a severe condition that results from chronic exposure to elevated circulating cortisol levels; it is a rare but potentially life-threating condition, especially when not timely diagnosed and treated. Even though the diagnosis can be straightforward in florid cases due to their typical phenotype, milder forms can be missed. Despite the availability of different screening tests, the diagnosis remains challenging as none of the available tools proved to be fully accurate. Due to the ubiquitous effect of cortisol, it is easy understandable that its excess leads to a variety of systemic complications including hypertension, metabolic syndrome, bone damages and neurocognitive impairment. This article discusses clinical presentation of CS with an eye on the most frequent cortisol-related comorbidities and discuss the main pitfalls of first- and second-line tests in endogenous hypercortisolism diagnostic workup.

Circulating Irisin Levels as a Marker of Osteosarcopenic-Obesity in Cushing's Disease

PURPOSE

To evaluate circulating irisin levels in patients with active and controlled Cushing's disease (CD).

DESIGN

Forty-four patients with CD evaluated during the active phase and after 12 months of biochemical remission and 40 controls were recruited.

METHODS

Phenotypic, anthropometric, hormonal and metabolic parameters, including insulin sensitivity estimation by homeostatic model of insulin resistance, Matsuda index and oral disposition index and circulating irisin levels were evaluated.

RESULTS

Patients with active CD showed lower irisin levels compared to controls (p<0.001) and controlled CD (p<0.001). The independent variables significantly associated with irisin were waist circumference (WC) (p=0.025), body fat percentage (BF%) (p=0.009), PTH (p=0.007) and chair rising test (CRT) (p<0.001) in active CD and WC (p=0.013), BF% (p=0.014), PTH (p=0.038), CRT (p=0.029) and urinary-free cortisol (p<0.001) in controlled CD.

CONCLUSION

Circulating irisin levels tend to be lower in patients with active CD compared to those with controlled CD and controls. They are strongly associated with osteosarcopenia and central obesity in CD and therefore may be a possible marker of diagnosis.

Glucocorticoid Receptor Polymorphisms Influence Muscle Strength in Cushing's Syndrome

CONTEXT

An important clinical feature of Cushing's syndrome (CS) is proximal muscle myopathy caused by glucocorticoid induced protein metabolism. However, interindividual differences cannot be explained solely by the pure extent of hypercortisolemia.

OBJECTIVE

To evaluate the effects of glucocorticoid receptor (GR) polymorphisms (BclI, N363S, ER22/23EK and A3669G), which influence peripheral glucocorticoid sensitivity on muscular function in endogenous CS.

METHODS

205 patients with proven endogenous CS (128 central, 77 adrenal) from 3 centers of the German Cushing's Registry and 125 subjects, in whom CS was ruled out, were included. All subjects were assessed for grip strength (via hand grip dynamometer) and performed a chair-rising test (CRT). DNA samples were obtained from peripheral blood leukocytes for GR genotyping.

RESULTS

In patients with active CS, normalized handgrip strength of the dominant and nondominant hand was higher in A3669G minor allele than in wildtype carriers (P = .006 and P = .021, respectively). CS patients in remission and ruled-out CS showed no differences in handgrip strength regarding A3669G minor allele and wildtype carriers. Male CS patients harboring the ER22/23EK wildtype presented lower hand grip strength than minor allele carriers (P = .049 dominant hand; P = .027 nondominant hand). The other polymorphisms did not influence handgrip strength. CRT showed no differences regarding GR polymorphisms carrier status.

CONCLUSION

Handgrip strength seems to be more susceptible to hypercortisolism in A3669G wildtype than in A3669G minor allele carriers. This might partially explain the inter-individual differences of glucocorticoid-induced myopathy in patients with endogenous CS. ER22/23EK polymorphism seems to exert sex-specific differences.

Effect of the severity of acute graft-versus-host disease on physical function after allogeneic hematopoietic stem cell transplantation

PURPOSE

The purpose of this study was to retrospectively investigate the effect of the severity of acute graft-versus-host disease (GVHD) on physical function after allogeneic hematopoietic stem cell transplantation (allo-HSCT).

METHODS

76 patients were included as subjects of this study. Severity of acute GVHD was classified according to the method defined by Grucksberg. To evaluate physical function, the knee extensor strength and six-minute walk distance (6MWD) were performed.

RESULTS

Among these patients, 54% developed acute GVHD; of these, 32%, 54%, and 15% of patients had grade I, grade II, and grades III-IV GVHD, respectively. In the grade I-II groups, mild acute GVHD following allo-HSCT resulted in a gradual decline in physical function, which improved at discharge. However, in cases of severe acute GVHD, physical function deteriorated, implementation of rehabilitation became difficult, and the decline in physical function persisted even at discharge.

CONCLUSION

These results indicate that severe acute GVHD negatively affects physical function leading to longer hospital days because of inadequate rehabilitation interventions.

Ultrasound-based detection of glucocorticoid-induced impairments of muscle mass and structure in Cushing's disease

PURPOSE

To investigate the glucocorticoid-induced impairments of muscle mass and structure in patients presenting different stages of steroid myopathy progression.

METHODS

Thirty-three patients (28 women) affected by active (N = 20) and remitted (N = 13) Cushing's disease were recruited and the following variables were assessed: walking speed, handgrip strength, total body and appendicular muscle mass by bioelectrical impedance analysis (BIA), thickness and echo intensity of lower limb muscles by ultrasonography.

RESULTS

The two groups of patients showed comparable values of both handgrip strength [median (interquartile range) values: active disease: 27.4 (7.5) kg vs. remitted disease: 26.4 (9.4) kg; P = 0.58] and walking speed [active disease: 1.0 (0.2) m/s vs. remitted disease: 1.1 (0.3) m/s; P = 0.43]. Also, the thickness of the four muscles and all BIA-derived sarcopenic indices were comparable (P > 0.05 for all comparisons) between the two groups. On the contrary, the echo intensity of vastus lateralis, tibialis anterior (lower portion), and medial gastrocnemius was significantly (P < 0.05 for all comparisons) higher in patients with active disease compared to patients with remitted disease. Finally, significant negative correlations were found in the whole group of patients between muscle echo intensity and muscle function assessments.

CONCLUSIONS

We provided preliminary evidence that the ultrasound-derived measurements of muscle thickness and echo intensity can be useful to detect and track the changes of muscle mass and structure in patients with steroid myopathy and we suggest that the combined assessment of muscle mass, strength, and performance should be systematically applied in the routine examination of steroid myopathy patients.

MECHANISMS OF ENDOCRINE DISEASE: Sarcopenia in endocrine and non-endocrine disorders

Objective This paper reviews the main mechanisms, diagnostic criteria, treatment options and available data on sarcopenia in endocrine and non-endocrine disorders. The literature notes the presence of sarcopenia as a comorbid condition or a complication of another clinical situation and not a disease that only affects elderly patients. Method We performed a literature review, focusing on the following: mechanisms related to sarcopenia in elderly patients, and sarcopenia as it presents in the context of chronic and endocrine diseases; diagnostic tools and methods; aspects of sarcopenia and treatment options specific to chronic diseases and endocrine disorders respectively. Results Sarcopenia in chronic and endocrine disorders shares many mechanisms with sarcopenia affecting elderly patients, but certain diseases can have a predominant aspect that leads to sarcopenia. The prevalence of sarcopenia varies, depending on different diagnostic criteria, from around 12 to 60% in chronic illnesses and 15 to 90% in endocrine disorders. The interplay between sarcopenia, chronic diseases and elderly patients requires further study, to clarify the impact of each, in terms of prognosis and mortality. Conclusion Awareness of the presentation of sarcopenia in the context of other diseases and ages (and not just the elderly) is fundamental to ensure that preventive measures can be deployed.

The Differential Effect of Excess Aldosterone on Skeletal Muscle Mass by Sex

The effects of excess aldosterone on skeletal muscle in individuals with primary aldosteronism (PA) are unknown. To examine the effects of aldosterone on skeletal muscle mass in patients with PA, by sex, 309 consecutive patients were enrolled. Skeletal muscle and fat mass of 62 patients with PA were compared with those of 247 controls with non-functioning adrenal incidentaloma (NFAI). Body composition parameters were measured using bioelectrical impedance analysis, and plasma aldosterone concentration (PAC) was measured using radioimmunoassay. The PAC in all women, but not in men, showed an inverse association with both appendicular skeletal muscle mass (ASM) (β = -0.197, P = 0.016) and height-adjusted ASM (HA-ASM) (β = -0.207, P = 0.009). HA-ASM in women (but not in men) with PA was 5.0% lower than that in women with NFAI (P = 0.036). Furthermore, women with PA had a lower HA-ASM than 1:1 age- and sex-matched controls with NFAI by 5.7% (P = 0.049) and tended to have a lower HA-ASM than 1:3 age-, sex-, and menopausal status-matched controls without adrenal incidentaloma (AI) by 7.3% (P = 0.053). The odds ratio (OR), per quartile increase in PAC, of low HA-ASM in women was 1.18 [95% confidence interval (CI), 1.01-1.39; P = 0.035]. The odds of HA-ASM in subjects with PA were 10.63-fold (95% CI: 0.83-135.50) higher, with marginal significance (P = 0.069) than in those with NFAI. Skeletal muscle mass in women with PA was lower than that in women with NFAI; suggesting that excess aldosterone has adverse effects on skeletal muscle metabolism.

Cardiovascular Health in Children and Adolescents With Congenital Adrenal Hyperplasia Due to 21-Hydroxilase Deficiency

Increasing evidence indicates that adults with Congenital Adrenal Hyperplasia (CAH) may have a cluster of cardiovascular (CV) risk factors. In addition, ongoing research has highlighted that children and adolescents with CAH are also prone to developing unfavorable metabolic changes, such as obesity, hypertension, insulin resistance, and increased intima-media thickness, which places them at a higher risk of developing CV disease in adulthood. Moreover, CAH adolescents may exhibit subclinical left ventricular diastolic dysfunction and impaired exercise performance, with possible negative consequences on their quality of life. The therapeutic management of patients with CAH remains a challenge and current treatment regimens do not always allow optimal biochemical control. Indeed, overexposure to glucocorticoids and mineralocorticoids, as well as to androgen excess, may contribute to the development of unfavorable metabolic and CV abnormalities. Long-term prospective studies on large cohorts of patients will help to clarify the pathophysiology of metabolic alterations associated with CAH. Meanwhile, further efforts should be made to optimize treatment and identify new therapeutic approaches to prevent metabolic derangement and improve long-term health outcomes of CAH patients.

Diagnostic evaluation in steroid-induced myopathy: case report suggesting clinical utility of quantitative muscle ultrasonography

PURPOSE

We present a patient with adrenal Cushing's syndrome causing steroid myopathy. The purpose of the case report is to illustrate the clinical usefulness of quantitative muscle ultrasonography for the assessment of glucocorticoid-induced changes in muscle mass (MM) and structure.

METHODS

Assessments of physical performance, muscle strength, MM (i.e., total body skeletal MM, appendicular skeletal MM, and thickness of lower limb muscles), and muscle structure (i.e., echo intensity of lower limb muscles) were performed in the patient both in the active phase of the disease (preoperatively) and 6 months after surgical intervention (postoperatively).

RESULTS

Muscle strength, physical performance, and MM were low both preoperatively and postoperatively. We also found preoperatively an increased echo intensity that normalized postoperatively.

CONCLUSIONS

Clinical implications of these findings are double-fold. First, although the muscle structure can recover quickly in steroid myopathy patients, the recovery of MM may take months to years. Second, we show that muscle echo intensity can be useful to track the progression of steroid myopathy overtime and may help to indicate early response to therapeutic interventions. Further prospective studies are needed to confirm the value of muscle echo intensity in patients with endogenous or exogenous Cushing's syndrome presenting with steroid myopathy.

An unusual case of shortness of breath

Myopathy is a well-known complication of hypercortisolism and commonly involves proximal lower-limb girdle. We report a rare case of Cushing’s syndrome in a 60-year-old female presenting with significant respiratory muscle weakness and respiratory failure. She had history of rheumatoid arthritis, primary biliary cirrhosis and primary hypothyroidism and presented with weight gain and increasing shortness of breath. Investigations confirmed a restrictive defect with impaired gas transfer but with no significant parenchymatous pulmonary disease. Respiratory muscle test confirmed weakness of respiratory muscles and diaphragm. Biochemical and radiological investigations confirmed hypercortisolaemia secondary to a left adrenal tumour. Following adrenalectomy her respiratory symptoms improved along with an objective improvement in the respiratory muscle strength, diaphragmatic movement and pulmonary function test.

Alteration in skeletal muscle mass in women with subclinical hypercortisolism

PURPOSE

Despite the well-known deleterious effects of cortisol on skeletal muscle, whether subtle cortisol excess in subclinical hypercortisolism (SH) affects skeletal muscle mass is unknown. Our objective was to understand the effects of the cortisol level on skeletal muscle mass in patients with SH.

METHODS

We compared skeletal muscle mass and fat mass (FM) between 21 patients with SH (12 women and 9 men) and 224 controls (67 women and 157 men) with nonfunctioning adrenal incidentaloma (NFAI). Medical records were reviewed, and we measured body composition parameters using bioelectrical impedance analysis and serum cortisol levels after the overnight 1-mg dexamethasone suppression test (DST).

RESULTS

After adjusting for confounding factors, 1-mg DST levels were inversely correlated with appendicular skeletal muscle mass (ASM) (γ = -0.245, P = 0.040), lower limb ASM (γ = -0.244, P = 0.040), and appendicular skeletal muscle index (ASMI; height-adjusted ASM) (γ = -0.229, P = 0.048) in all women, but not men. ASM and ASMI were significantly lower by 6.2% (P = 0.033) and 5.9% (P = 0.046), respectively, in women with SH compared with those with NFAI, but not men. Conversely, FM and percent fat mass were similar between the two groups. Compared with women with NFAI, among those with SH, lower limb, but not upper limb, ASM was lower by 6.8% (P = 0.020).

CONCLUSIONS

This study showed that women with SH had lower skeletal muscle mass, especially of the lower limb, and suggested that subtle cortisol excess also has adverse effects on skeletal muscle metabolism.

Physiological culture conditions alter myotube morphology and responses to atrophy treatments: implications for in vitro research on muscle wasting

Standard in vitro myotube culture conditions are nonphysiological and there is increasing evidence that this may distort adaptations to both catabolic and anabolic stimuli and hamper preclinical research into mechanisms and treatments for muscle atrophy in cancer and other chronic diseases. We tested a new model of myotube culture which mimics more accurately the basal conditions for muscle tissue in patients with chronic disease, such as cancer. Myotubes derived from C2C12 myoblasts, cultured under the modified conditions were thinner, more numerous, with more uniform morphology and an increased proportion of mature myotubes. Furthermore, modified conditions led to increased expression of mir-210-3p, genes related to slow-twitch, oxidative phenotype and resistance to commonly used experimental atrophy-inducing treatments. However, treatment with a combination of drugs used in anti-cancer treatment (doxorubicin and dexamethasone) under the modified culture conditions did lead to myotube atrophy which was only partially prevented by co-administration of curcumin. The results underline the importance and potential advantages of using physiological conditions for in vivo experiments investigating mechanisms of muscle atrophy and especially for preclinical screening of therapies for cancer-related muscle wasting.

Diagnostic work-up in steroid myopathy

INTRODUCTION

Steroid myopathy is a well-known sign of endogenous Cushing's syndrome as well as a side effect of glucocorticoid administration. The clinical finding of muscle weakness and the clinical inspection of the muscle size are the most commonly used diagnostic tools, sometimes in combination with needle electromyography, but there are no means to detect the myopathy before the appearance of clinical or electrodiagnostic signs. Until now, no guidelines have been produced for a disease-specific evaluation of muscle impairment in patients with Cushing's syndrome.

REVIEW

We reviewed the measurement properties and limitations of the following tools that are currently adopted in clinical research and routine care for diagnosis and monitoring of steroid myopathy: muscle strength assessment; needle biopsy; intramuscular and surface electromyography; laboratory assays; muscle mass assessments (through bioelectrical impedance analysis, dual-energy X-ray absorptiometry, and computed tomography).

CONCLUSIONS

We suggest that the management of steroid myopathy patients in clinical research and practice would benefit from a multidisciplinary approach based on the combined assessment of muscle mass, strength, and performance. However, further studies are required to establish an operational definition of steroid myopathy and to identify population-specific criteria for diagnosis of the myopathic process.

Impact of HSCT Conditioning and Glucocorticoid Dose on Exercise Adherence and Response

PURPOSE

Evidence from randomized controlled trials (RCT) that exercise interventions have beneficial effects in patients undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT) is growing. However, intensive chemotherapy conditioning and glucocorticoid (GC) treatment is always part of an allo-HSCT and possibly affect exercise adherence and training response. Therefore, we aimed to examine whether various conditioning protocols or different doses of GC treatment affect exercise adherence and/or training response during the inpatient period.

METHODS

We analyzed inpatient data from intervention groups of two large RCT in allo-HSCT patients (n = 113). The intervention incorporated partly supervised endurance and resistance exercise three to five times per week. According to the potentially interfering factors, the patients were divided into groups depending on intensity of conditioning (myeloablative conditioning (MAC), reduced-intensity conditioning (RIC), and nonmyeloablative conditioning (NMC)) and cumulative dose of GC treatment (GC low ≤9 mg·kg prednisone or GC high >9 mg·kg prednisone) and were compared.

RESULTS

Median exercise adherence (target value, five sessions weekly) during the inpatient period was 64% in MAC, 54% in RIC, and 63% in NMC. The proportion of prematurely terminated training sessions ranged from 11% to 15%. Tiredness was the most frequent cause of exercise termination in all groups. Exercise adherence, duration (min·wk) and type of training was significantly associated with GC dose. With regard to training response, results suggest that GC-low patients tend to respond better in knee extensor muscle strength.

CONCLUSIONS

Exercise adherence during inpatient period is significantly affected by dose of GC treatment but not by condition regimen. However, given the reasonable adherence rates also in the GC-high group, data support the feasibility and importance of exercising for all allo-HSCT patients during the inpatient period.

Factors influencing spinal sagittal balance, bone mineral density, and Oswestry Disability Index outcome measures in patients with rheumatoid arthritis

PURPOSE

To identify the factors influencing spinal sagittal alignment, bone mineral density (BMD), and Oswestry Disability Index (ODI) outcome measures in patients with rheumatoid arthritis (RA).

METHODS

We enrolled 272 RA patients to identify the factors influencing sagittal vertical axis (SVA). Out of this, 220 had evaluation of bone mineral density (BMD) and vertebral deformity (VD) on the sagittal plane; 183 completed the ODI questionnaire. We collected data regarding RA-associated clinical parameters and standing lateral X-ray images via an ODI questionnaire from April to December 2012 at a single center. Patients with a history of spinal surgery or any missing clinical data were excluded. Clinical parameters included age, sex, body mass index, RA disease duration, disease activity score 28 erythrocyte sedimentation rate (DAS28-ESR), serum anti-cyclic citrullinated peptide antibody, serum rheumatoid factor, serum matrix metalloproteinase-3, BMD and treatment type at survey, such as methotrexate (MTX), biological disease-modifying anti-rheumatic drugs, and glucocorticoids. We measured radiological parameters including pelvic incidence (PI), lumbar lordosis (LL), and SVA. We statistically identified the factors influencing SVA, BMD, VD, and ODI using multivariate regression analysis.

RESULTS

Multivariate regression analysis showed that larger SVA correlated with older age, higher DAS28-ESR, MTX nonuse, and glucocorticoid use. Lower BMD was associated with female, older age, higher DAS28-ESR, and MTX nonuse. VD was associated with older age, longer disease duration, lower BMD, and glucocorticoid use. Worse ODI correlated with older age, larger PI-LL mismatch or larger SVA, higher DAS28-ESR, and glucocorticoid use.

CONCLUSIONS

In managing low back pain and spinal sagittal alignment in RA patients, RA-related clinical factors and the treatment type should be taken into consideration.

Acute myopathy following intra-muscular injection of compound betamethasone: A case report

RATIONALE

We report a case of acute steroid myopathy in a patient with eczema receiving one dose of intra-muscular injection of Compound betamethasone.

PATIENT CONCERNS

Acute steroid myopathy (ASM) is usually caused by exogenous corticosteroids, and typically, occurs with therapy using intravenous corticosteroids at high doses.

DIAGNOSES

The patient was considered as a diagnosis of acute steroid myopathy.

INTERVENTIONS

The patient was treated with non-steroid anti-inflammatory drug and other symptomatic therapy.

OUTCOMES

ASM was gradually improved after 2 weeks symptomatic treatment and completely recovered after one-month treatment.

LESSONS

The diagnosis of steroid myopathy is a clinical diagnosis based on characteristic symptoms. Higher dose of steroids, especially fluorinated steroids, for longer periods of time increases the risk of steroid-induced myopathy.

Persistence of myopathy in Cushing's syndrome: evaluation of the German Cushing's Registry

BACKGROUND

Cushing's syndrome (CS) is characterized by an excessive secretion of glucocorticoids that results in a characteristic clinical phenotype. One feature of clinical hypercortisolism is breakdown of protein metabolism translating into clinical consequences including glucocorticoid-induced myopathy. While surgery is effective in control of cortisol excess, the effect of biochemical remission on muscular function is yet unclear.

METHODS

In a cross-sectional study we analyzed 47 patients with CS during the florid phase (ActiveCS). 149 additional patients were studied 2-53 years (mean: 13 years) after surgery in biochemical long-term remission (RemissionCS). Also, 93 rule-out CS patients were used as controls (CON). All subjects were assessed for grip strength using a hand grip dynamometer and underwent the chair rising test (CRT).

RESULTS

Hand grip strength (85% vs 97% of norm, P = 0.002) and the CRT performance (9.5 s vs 7.1 s, P = 0.001) were significantly lower in ActiveCS compared to the CON group. Six months after treatment grip strength further decreased in CS (P = 0.002) and CRT performance remained impaired. The RemissionCS group (mean follow-up 13 years) had reduced hand grip strength (92% compared to normal reference values for dominant hand, P < 0.001). The chair rising test performance was at 9.0 s and not significantly different from the ActiveCS group (P = 0.45).

CONCLUSION

CS affects muscle strength in the acute phase, but functional impairment remains detectable also during long-term follow-up despite biochemical remission.

Complications of Cushing's syndrome: state of the art

Cushing's syndrome is a serious endocrine disease caused by chronic, autonomous, and excessive secretion of cortisol. The syndrome is associated with increased mortality and impaired quality of life because of the occurrence of comorbidities. These clinical complications include metabolic syndrome, consisting of systemic arterial hypertension, visceral obesity, impairment of glucose metabolism, and dyslipidaemia; musculoskeletal disorders, such as myopathy, osteoporosis, and skeletal fractures; neuropsychiatric disorders, such as impairment of cognitive function, depression, or mania; impairment of reproductive and sexual function; and dermatological manifestations, mainly represented by acne, hirsutism, and alopecia. Hypertension in patients with Cushing's syndrome has a multifactorial pathogenesis and contributes to the increased risk for myocardial infarction, cardiac failure, or stroke, which are the most common causes of death; risks of these outcomes are exacerbated by a prothrombotic diathesis and hypokalaemia. Neuropsychiatric disorders can be responsible for suicide. Immune disorders are common; immunosuppression during active disease causes susceptibility to infections, possibly complicated by sepsis, an important cause of death, whereas immune rebound after disease remission can exacerbate underlying autoimmune diseases. Prompt treatment of cortisol excess and specific treatments of comorbidities are crucial to prevent serious clinical complications and reduce the mortality associated with Cushing's syndrome.

Neuromuscular complications in cancer

Cancer is becoming a treatable and even often curable disease. The neuromuscular system can be affected by direct tumor invasion or metastasis, neuroendocrine, metabolic, dysimmune/inflammatory, infections and toxic as well as paraneoplastic conditions. Due to the nature of cancer treatment, which frequently is based on a DNA damaging mechanism, treatment related toxic side effects are frequent and the correct identification of the causative mechanism is necessary to initiate the proper treatment. The peripheral nervous system is conventionally divided into nerve roots, the proximal nerves and plexus, the peripheral nerves (mono- and polyneuropathies), the site of neuromuscular transmission and muscle. This review is based on the anatomic distribution of the peripheral nervous system, divided into cranial nerves (CN), motor neuron (MND), nerve roots, plexus, peripheral nerve, the neuromuscular junction and muscle. The various etiologies of neuromuscular complications - neoplastic, surgical and mechanic, toxic, metabolic, endocrine, and paraneoplastic/immune - are discussed separately for each part of the peripheral nervous system.

Quantitative and qualitative adaptations of muscle fibers to glucocorticoids

INTRODUCTION

The aim of this study was to understand the effects of short-term glucocorticoid administration in healthy subjects.

METHODS

Five healthy men received dexamethasone (8 mg/day) for 7 days. Vastus lateralis muscle biopsy and knee extension torque measurement were performed before and after administration. A large number of individual muscle fibers were dissected from the biopsy samples (pre-administration: n = 165, post-administration: n = 177).

RESULTS

Maximal knee extension torque increased after administration (∼ 13%), whereas both type 1 and type 2A fibers had decreased cross-sectional area (type 1: ∼ 11%, type 2A: ∼ 17%), myosin loss (type 1: ∼ 18%, type 2A: ∼ 32%), and loss of specific force (type 1: ∼ 24%, type 2A: ∼ 33%), which were preferential for fast fibers.

CONCLUSION

Short-term dexamethasone administration in healthy subjects elicits quantitative and qualitative adaptations of muscle fibers that precede (and may predict) the clinical appearance of myopathy in glucocorticoid-treated subjects.

Sarcopenia in Endocrine Disorders - The Iceberg or Its Tip?

Endocrine myopathies represent disorders of the musculoskeletal system that significantly impair the state of health. Sarcopenia is their pathophysiological common denominator. Recent reports have shown that endocrine disorders, even when subclinical, may also be associated with tendinopathies. It may thus be suggested that both hormones and hormonal disorders have complex actions on the musculoskeletal system and that musculoskeletal endocrinology represents a fascinating research area still awaiting exploration.

Cardiovascular abnormalities and impaired exercise performance in adolescents with congenital adrenal hyperplasia

CONTEXT

PATIENTS with classic congenital adrenal hyperplasia (CAH) are treated with lifelong glucocorticoids (GCs). Cardiovascular and metabolic effects of such therapy in adolescents have never been quantified.

OBJECTIVE

Our objective was to investigate left ventricular (LV) morphology, function, and exercise performance in adolescents with CAH.

DESIGN AND SETTING

We conducted a cross-sectional and controlled study conducted at a tertiary referral center.

PATIENTS

Twenty patients with classic CAH (10 females) aged 13.6 ± 2.5 years and 20 healthy controls comparable for sex and pubertal status were enrolled in the study and compared with a group of 18 patients without CAH receiving a similar dose of GCs for juvenile idiopathic arthritis.

MAIN OUTCOMES MEASURES

Echocardiographic assessment and symptom-limited exercise testing were performed. Anthropometric, hormonal and biochemical parameters were also measured.

RESULTS

Compared with healthy controls, patients with CAH exhibited an increased body mass index (P < .001), waist-to-height ratio (P < .001), and percent body fat (P < .001) as well as higher insulin concentrations and homeostasis model assessment of insulin resistance index even after adjustment for body mass index (P = .03 and P = .05, respectively). Moreover, CAH patients exhibited an impaired exercise capacity as shown by reduced peak workload (99 ± 27 vs 126 ± 27 W, P < .01) and higher systolic blood pressure response at peak (156 ± 18 vs 132 ± 11 mm Hg, P < .01; Δ = 45 ± 24 vs 22 ± 10 mm Hg, P = .05) with respect to healthy controls. CAH males displayed mild LV diastolic dysfunction as documented by significant prolongation of both isovolumic relaxation time (118 ± 18 vs 98 ± 11 milliseconds, P < .05) and mitral deceleration time (138 ± 25 vs 111 ± 15 milliseconds, P < .01). No significant differences in cardiovascular function were found between CAH and juvenile idiopathic arthritis patients.

CONCLUSION

Adolescents with CAH exhibit impaired exercise performance and enhanced systolic blood pressure response during exercise. In our population, such abnormalities appear related to GC therapy rather than CAH per se. CAH males, but not females, present mild LV diastolic dysfunction that correlates with testosterone concentrations suggesting a sex hormone-related difference.

Advances in the epidemiology, pathogenesis, and management of Cushing's syndrome complications

Cushing's syndrome (CS) is a clinical condition resulting from chronic exposure to glucocorticoid excess. As a consequence, hypercortisolism contributes significantly to the early development of systemic disorders by direct and/or indirect effects. Complications such as obesity, hypertension, diabetes, dyslipidemia, and hypercoagulability cause premature atherosclerosis and increase cardiovascular mortality. Impairment of the skeletal system is a relevant cause of morbidity and disability in these patients especially due to the high prevalence of vertebral fractures. In addition, muscle weakness, emotional lability, depression, and impairment of quality of life are very common. Clinical management of these patients is complex and should be particularly careful in identifying global cardiovascular risks and aim at controlling all complications. Although the primary goal in the prevention and treatment of complications is the correction of hypercortisolism, treatment does not completely eliminate these comorbidities. Given that cardiovascular risk and fracture risk can persist after cure, early detection of each morbidity could prevent the development of irreversible damage. In this review we present the various complications of CS and their pathogenetic mechanisms. We also suggest the clinical management of these patients based on our extensive clinical experience and on the available literature.