Bone health in Parkinson's disease: a systematic review and meta-analysis

[Neuroendocrine and metabolic impairments in patients with Parkinson's disease]

ABSRACT

Neuroendocrine and neurometabolic disorders, although occasionally noted in Parkinson's disease (PD), existed in the shadow of motor and non-motor symptoms (hypokinesia, rigidity, tremor, depression, constipation, etc.). In recent years, they are increasingly being diagnosed and are the subject of special research. These include, in particular, disorders of carbohydrate metabolism, changes in body weight, metabolic disorders in bone tissue, secretion, as well as the secretion of neurohormones, such as melatonin. They are associated with other non-motor symptoms, negatively affect patients' general condition and quality of life, but can be treatable. At the same time, treatment of neuroendocrine and neurometabolic disorders can favorably influence the rate of progression of the disease as a whole. This review discusses the pathophysiological mechanisms, clinical consequences, as well as pharmacological and non-pharmacological approaches to the treatment of neuroendocrine and neurometabolic disorders arising in PD, which have been relatively rarely covered in literature.

Longitudinal prediction of falls and near falls frequencies in Parkinson's disease: a prospective cohort study

Introduction and objective

Several prediction models for falls/near falls in Parkinson’s disease (PD) have been proposed. However, longitudinal predictors of frequency of falls/near falls are poorly investigated. Therefore, we aimed to identify short- and long-term predictors of the number of falls/near falls in PD.

Methods

A prospective cohort of 58 persons with PD was assessed at baseline (mean age and PD duration, 65 and 3.2 years, respectively) and 3.5 years later. Potential predictors were history of falls and near falls, comfortable gait speed, freezing of gate, dyskinesia, retropulsion, tandem gait (TG), pain, and cognition (Mini-Mental State Exam, MMSE). After each assessment, the participants registered a number of falls/near falls during the following 6 months. Multivariate Poisson regression was used to identify short- and long-term predictors of a number of falls/near falls.

Results

Baseline median (q1–q3) motor (UPDRS) and MMSE scores were 10 (6.75–14) and 28.5 (27–29), respectively. History of falls was the only significant short-time predictor [incidence rate ratio (IRR), 15.17] for the number of falls/near falls during 6 months following baseline. Abnormal TG (IRR, 3.77) and lower MMSE scores (IRR, 1.17) were short-term predictors 3.5 years later. Abnormal TG (IRR, 7.79) and lower MMSE scores (IRR, 1.49) at baseline were long-term predictors of the number of falls/near falls 3.5 years later.

Conclusion

Abnormal TG and MMSE scores predict the number of falls/near falls in short and long term, and may be indicative of disease progression. Our observations provide important additions to the evidence base for clinical fall prediction in PD.

Vitamin D and Hyperkinetic Movement Disorders: A Systematic Review

Background

The importance of vitamin D deficiency in Parkinson's disease, its negative influence on bone health, and even disease pathogenesis has been studied intensively. However, despite its possible severe impact on health and quality of life, there is not a sufficient understanding of its role in other movement disorders. This systematic review aims at providing an overview of the prevalence of vitamin D deficiency, bone metabolism alterations, and fractures in each of the most common hyperkinetic movement disorders (HKMDs).

Methods

The study search was conducted through PubMed with keywords or Medical Related Subjects (MeSH) of common HKMDs linked with the terms of vitamin D, osteoporosis, injuries, and fractures.

Results

Out of 1585 studies screened 40 were included in our review. They show that there is evidence that several HKMDs, including Huntington disease, Restless Legs Syndrome, and tremor, are associated with low vitamin D serum levels in up to 83% and 89% of patients. Reduced bone mineral density associated with vitamin D insufficiency was described in Huntington disease.

Discussion

Our survey suggests that vitamin D deficiency, bone structure changes, and fractures are important but yet under-investigated issues in HKMDs. HKMDs-patients, particularly with a history of previous falls, should have their vitamin D-levels tested and supplemented where appropriate.

Highlights

Contrary to Parkinson's disease, vitamin D deficiency, and bone abnormalities are under-investigated in hyperkinetic movement disorders (HKMDs). Several HKMDs, including essential tremor, RLS, and Huntington disease, are associated with vitamin D deficiency in up to 89%, the latter also with reduced bone mineral density. Testing and where appropriate supplementation is recommended.

Dopamine induces in vitro migration of synovial fibroblast from patients with rheumatoid arthritis

Preventing synovial fibroblast (SF) migration into the adjacent cartilage is a desirable therapeutic target in rheumatoid arthritis (RA). As previous studies demonstrated that RASF and SF from osteoarthritis (OA) patients express dopamine receptors (DR), aim of the present study was to investigate the impact of dopamine on mobility of fibroblasts from patients with chronic arthritides. Synovial tissue and fibroblasts were obtained from RA and OA patients. Immunohistochemistry was performed for all DR-subtypes in the invasion zone. Migration- and motility-assays were performed under DR-stimulation. Cytokines were evaluated using ELISA. Expression of DRs was evaluated by flow cytometry, and DR activation was measured by xCELLigence real-time analysis. All DRs were expressed in RA invasion zone. Migration and motility of RASF and OASF were increased after DR stimulation in patients ≤ 75 years old. Synovial fibroblasts from older RA patients (> 75 years old) expressed lower levels of D1-, D2- and D4-DR than patients ≤ 75 years old. DR activation was not altered in older patients. Our results suggest a possible involvement of dopamine on migration of fibroblasts from arthritis patients. Therefore, the synovial dopaminergic pathway might represent a potential therapeutic target to interfere with progressive joint damage in RA patients.

Crosstalk of Brain and Bone-Clinical Observations and Their Molecular Bases

As brain and bone disorders represent major health issues worldwide, substantial clinical investigations demonstrated a bidirectional crosstalk on several levels, mechanistically linking both apparently unrelated organs. While multiple stress, mood and neurodegenerative brain disorders are associated with osteoporosis, rare genetic skeletal diseases display impaired brain development and function. Along with brain and bone pathologies, particularly trauma events highlight the strong interaction of both organs. This review summarizes clinical and experimental observations reported for the crosstalk of brain and bone, followed by a detailed overview of their molecular bases. While brain-derived molecules affecting bone include central regulators, transmitters of the sympathetic, parasympathetic and sensory nervous system, bone-derived mediators altering brain function are released from bone cells and the bone marrow. Although the main pathways of the brain-bone crosstalk remain ‘efferent’, signaling from brain to bone, this review emphasizes the emergence of bone as a crucial ‘afferent’ regulator of cerebral development, function and pathophysiology. Therefore, unraveling the physiological and pathological bases of brain-bone interactions revealed promising pharmacologic targets and novel treatment strategies promoting concurrent brain and bone recovery.

Parkinson's disease and the non-motor symptoms: hyposmia, weight loss, osteosarcopenia

Non-motor symptoms (NMSs) are common in Parkinson's disease (PD) and can precede, sometimes for several years. NMSs include, other than gastrointestinal symptoms like constipation and dysphagia, also hyposmia, weight loss and osteosarcopenia. These three NMSs seem to be inter-related and affect patients' health and quality of life. Unfortunately, patients with these symptoms usually are not initially seen by a neurologist, and by the time they are consulted, nearly ~ 80% of the dopaminergic neurons in the substantia nigra have died. To date, no guidelines exist for screening, assessment and management of NMSs in general. A better understanding of these specific NMSs, likely in the context of others, will make it possible to approach and optimise the treatment of the motor symptoms thereby enhancing the welfare of PD patients. Identifying the NMSs could be very helpful, and among them, hyposmia, weight loss and osteosarcopenia may play an important role in solving the limitations in the diagnosis of PD. A strict collaboration between general practitioners, clinicians, geriatricians and neurologists can be one approach towards the diagnosis of pre-PD. Waiting until the motor symptoms develop and the patient is finally visited by the neurologist could be too late, considering the catastrophic prognosis of the disease.

Sagittal imbalance, muscle atrophy, and osteoporosis: risk factors for revision posterior lumbar fusion surgery in patients with Parkinson's disease

OBJECTIVE

The aim of our study was to evaluate features and complications of patients with Parkinson's disease (PD) who underwent posterior lumbar fusion surgery for lumbar degenerative diseases (LDD), as well as the risk factors for revision.

METHODS

Between January 2010 and December 2016, 132 patients were retrospectively identified for inclusion. Patients were divided into a 29 revision PD group and a 103 non-revision PD group. Patient factors included bone mineral density (BMD) and severity of PD using the Hoehn and Yahr staging system. Surgical factors included surgical levels and fusion methods. Radiographic measurements included pre-operative spinopelvic parameters, paraspinal muscle atrophy, and fatty infiltration. Logistic regression analysis was used to determine independent predictors for revision posterior lumbar fusion.

RESULTS

The average age of the PD patients was 67.96 years, and the follow-up time was 49.01 months. R-PD patients accounted for 21.97% of all PD patients who underwent lumbar fusion surgery. Multivariable analysis indicated that low BMD (p = 0.012), fatty infiltration (p = 0.038), a smaller relative cross-sectional area (rCSA) of the paraspinal muscle (p = 0.008), larger pelvic incidence-lumbar lordosis (PI-LL) (p = 0.01), and sagittal vertical axis (SVA) (p = 0.004) were significant independent risk factors for revision posterior lumbar fusion in PD patients.

CONCLUSION

PD patients with low pre-operative BMD, fatty infiltration, a smaller rCSA of the paraspinal muscle, and larger PI-LL and SVA had a higher rate of revision lumbar fusion. Maintaining sagittal balance, functional exercises, and anti-osteoporosis treatment were important in preventing complications in PD patients.

Bone Mineral Density and Risk of Osteoporotic Fractures in Women with Parkinson's Disease

Osteoporosis and Parkinson's disease (PD) are two important age-related diseases, which have an influence on pain, physical activity, disability, and mortality. The aim of this research was to study the parameters of bone mineral density (BMD), frequency, and 10-year probability of osteoporotic fractures (OFs) in females with Parkinson's disease (PD). We have examined 113 postmenopausal women aged 50-74 years old which were divided into 2 groups (I, control group (CG), n = 53 and II, subjects with PD, n = 60). Bone mineral density of lumbar spine, femoral neck, distal radius, and total body were measured, and quantity and localization of vertebral deformities were performed by the vertebral fracture assessment (VFA). Ten-year probability of OFs was assessed by Ukrainian version of FRAX®. It was established that BMD of lumbar spine, femoral neck, distal radius, and total body in PD women was reliably lower compared to CG. The frequency of OFs in PD subjects was higher compared to CG (51.7 and 11.3%, respectively) with prevalence of vertebral fractures (VFs) in women with PD (52.6% among all fractures). 47.4% of the females had combined VFs: 74.2% of VFs were in thoracic part of the spine and 73.7% were wedge ones. Ten-year probability of major OFs and hip fracture were higher in PD women compared to CG with and without BMD measurements. Inclusion of PD in the FRAX calculation increased the requirement of antiosteoporotic treatment from 5 to 28% (without additional examination) and increased the need of additional BMD measurement from 50 to 68%. Anterior/posterior vertebral height ratios (Th₈-Th₁₁) measured by VFA in PD females without confirmed vertebral deformities were lower compared to indices of CG. In conclusion, women with PD have lower BMD indices, higher rate of osteoporosis, and risk of future low-energy fractures that should be taken into account in the assessment of their osteoporosis risk and clinical management.

Movement disorders: a themed collection

Movement disorders are a diverse and challenging group of neurological conditions. Geriatricians and allied health professionals play a key role in the care of patients living with these disorders. Age and Ageing is making freely available online a collection of 15 papers that highlight the breadth and depth of this field. Perhaps unsurprisingly papers on Parkinson's disease predominate, but rarer movement disorders, including those seen following stroke and Huntington's disease, are also represented. Difficulties in diagnosis are explored, together with innovative approaches to management of both motor and non-motor symptoms. The collection includes qualitative work, longitudinal studies and clinical trials, and both the individual patient perspective and the international perspective are considered. There are papers for generalists, papers for specialists, papers for clinical commissioners and papers for researchers. Comprehensive review articles provide clarity, guidance and pragmatism. Finally, a New Horizons article encourages us to look to the future of movement disorders, which lies not only in developing novel therapies and trials but also in recognising the enormous value of palliative care and the multidisciplinary approach.

Relationship between 25-Hydroxyvitamin D, bone density, and Parkinson's disease symptoms

OBJECTIVES

Vitamin D deficiency is widespread in patients with Parkinson's disease (PD). Our aim was to determine whether serum vitamin D levels correlated with bone mineral density (BMD) and non-motor symptoms in patients with PD.

MATERIALS & METHODS

A consecutive series of 182 patients with PD and 185 healthy controls were included. Serum 25-hydroxyvitamin D (25[OH]D) levels were measured by immunoassay, while BMD of the lumbar spine and femoral neck was measured by dual-energy X-ray absorptiometry. Associations between serum vitamin D levels and clinical data were evaluated using partial correlation analysis.

RESULTS

Patients with PD had significantly lower serum 25(OH)D levels relative to healthy controls (49.75 ± 14.11 vs 43.40 ± 16.51, P < 0.001). Furthermore, PD patients with lower vitamin D levels had a significantly higher frequency of falls (P = 0.033) and insomnia (P = 0.015). They also had significantly higher scores for the Pittsburgh Sleep Quality Index (PSQI; P = 0.014), depression (P = 0.020), and anxiety (P = 0.009). Finally, patients with PD also had a significantly lower mean BMD of the lumbar spine (P = 0.011) and femoral neck (P < 0.001). After adjusting for age, sex, and body mass index, vitamin D levels significantly correlated with falls, insomnia, and scores for the PSQI, depression, and anxiety.

CONCLUSIONS

In patients with PD, vitamin D levels significantly correlated with falls and some non-motor symptoms. However, no associations were found between BMD and the serum 25(OH)D levels in patients with PD. Thus, vitamin D supplementation is a potential therapeutic for non-motor PD symptoms.

Effect of Parkinson's Disease on Hemiarthroplasty Outcomes After Femoral Neck Fractures

BACKGROUND

The purpose of this study was to evaluate the outcomes following hemiarthroplasty (HA) for femoral neck fractures (FNFs) in patients with Parkinson's disease (PD) compared with patients without PD.

METHODS

This was a retrospective review utilizing the Nationwide Readmissions Database, a national database incorporating inpatient hospitalization information. Using the Nationwide Readmissions Database, patients who underwent HA for FNF between 2010-2014 were identified. International Classification of Diseases, 9th Revision, codes were used to find a subset of patients with PD. Primary outcomes of interest included death, hospital readmission, periprosthetic fracture, postoperative dislocation, any revision surgery, and revision surgery for instability, fracture, or infection.

RESULTS

There were a total of 7721 (4%) patients with PD. There was no difference in the risk of death or any postoperative complications during index hospitalization for these patients. However, PD patients had an increased risk of hospital readmission (odds ratio [OR] = 1.13, 95% confidence interval [CI]: 1.02-1.26) and postoperative dislocation (OR = 2.10, 95% CI: 1.58-2.80) within 90 days of surgery. PD patients also had an increased risk of revision surgery for instability (OR = 2.20, 95% CI: 1.48-3.28), despite no difference in the risk of any revision surgery, revision surgery for fracture, or revision surgery for infection.

CONCLUSION

In this retrospective cohort study, PD patients who underwent a HA for FNF had a greater risk of postoperative dislocation and revision surgery for instability within 90 days. These findings are not only important to consider when managing these at-risk patients but also stress the need to allocate operative and postoperative resources to prevent and treat instability.

LEVEL OF EVIDENCE

3 (Retrospective cohort study).

Exercise for Parkinson's disease

Parkinson's disease is the second most common neurodegenerative disease with a prevalence rate of 1-2 per 1000 of the population worldwide. Pharmacological management is the mainstay of treatment. Despite optimal medication, motor impairment particularly balance and gait impairment persist leading to various degree of disability and reduced quality-of-life. The present review describes motor impairment including postural impairment, gait dysfunction, reduced muscle strength and aerobic capacity and falls. Physical therapy and complementary exercises have been proven to improve motor performance and functional mobility. Evidence on the efficacy of physical therapy and complementary exercises is presented in this review. These exercises include gait training with cues, gait training with treadmill, Nordic walking, brisk walking, balance training, virtual reality interventions, Tai Chi and dance. All these treatment interventions produce short-term beneficial effects and some interventions demonstrate long-term benefit. Gait training with treadmill enhance walking performance and the effects sustain for 3-6 months. Balance training improves balance, function and reduces fall rate, and these effects carry over to at least 12 months after training ended. Sustained Tai Chi for 6 months, dance therapy for 12 months, progressive resistive training for 24 months alleviates the PD motor symptoms, suggesting that they could slow down PD progression. Based on this evidence, individuals with PD are encouraged to sustain their training in order to improve/maintain their physical ability and to combat the progression of PD.

Management of fracture risk in Parkinson's: A revised algorithm and focused review of treatments

INTRODUCTION

Falls and fractures are a cause of substantial morbidity in Parkinson's. Despite an excess risk of both falls and osteoporosis, people with Parkinson's perceive that they are less likely to fracture than their peers, despite actually being at higher fracture risk. Recognising this increased risk, in 2014 we published an algorithm to guide management of fracture risk in this high-risk population. Recently, the National Osteoporosis Guideline Group (NOGG) published new guidance revising the 10 year fracture probability intervention thresholds for those over 70 years old to 20.3% for major osteoporotic fracture and 5.4% for hip fracture.

METHODS

In light of the new guidance, we have reappraised the use of two fracture prediction tools, Qfracture and FRAX, and have updated the algorithm to guide the management of bone health and fracture risk in people with Parkinson's.

RESULTS

We outline the treatment options available with particular consideration given to Parkinson specific factors that influence treatment choices.

CONCLUSION

This guidance is relevant to all healthcare specialist managing Parkinson's including neurologists, geriatricians and primary care practitioners.

The fate of thoracolumbar surgeries in patients with Parkinson's disease, and analysis of risk factors for revision surgeries

Background

Compared to patients without Parkinson’s disease (PD), patients with PD who underwent spinal surgeries were reported to have a relatively high complication rate. However, studies that analyze surgical risk factors for these patients are limited.

Methods

From October 2004 to April 2015, patients with PD who underwent spinal surgeries at our department were reviewed. Patients who underwent lumbar or thoracolumbar instrumented surgeries due to degeneration or deformity disease were included. Any reason for revision surgery was recorded. Risk factors including patients’ factors, surgical factors, and lumbo-pelvic radiographic parameters were analyzed. Patients’ factors included patients’ underlying diseases, body mass index (BMI), osteoporotic status, and PD’s severity using the modified Hoehn and Yahr staging scale. Surgical factors included surgical levels, extending to thoracic spine or not, corrective osteotomy, with anterior approach or not, and interbody device. Radiographic parameters included lumbar lordosis (LL), sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), coronal Cobb’s angles, and score for spino-pelvic realignment achievement.

Results

A total of 66 patients were enrolled. The mean age at surgery was 69.0 years old. The mean follow-up time was 51.2 months. Twenty-six revision surgeries were required in 19 patients (29%). Risk factors for revision surgery included modified Hoehn and Yahr stage ≥3 (p <  0.001), cancer history (p = 0.024), osteoporosis (P = 0.012) and underwent corrective osteotomy (p = 0.035). According to binary logistic regression analysis, the modified Hoehn and Yahr stage ≥3 (p <  0.001) was the only independent risk factor. The Kaplan-Meier analysis revealed patients with long instrumentation (surgical levels > 3), T-spine instrumentation, and lower score of spino-pelvic realignment achievement tended to have earlier revision.

Conclusion

For PD patients planning for elective thoracolumbar surgery, aggressive control status of PD before or after surgery is necessary to prevent surgical complications. Longer surgical levels and corrective osteotomy also tended to have earlier revision. A better score in spino-pelvic realignment achievement after surgery could reduce occurrence of revision.

Analysis of Relationships between Spinal Deformity and Walking Ability in Parkinson's Disease Patients

Introduction

This study aimed to determine impacts on walking ability of spinal deformity and imbalance as distinct from movement disorders in Parkinson's disease (PD).

Methods

Thirty-two patients (15 males, 17 females; mean age 72.5 years) were analyzed. Three, thirteen, eleven, and five were at Hoehn-Yahr stages I, II, III, and IV, respectively. In addition to various spinal imbalance and deformity classifications the following were assessed: Cobb angle (CA) for scoliosis, thoracic kyphosis (TK) at T2-12, thoracolumbar kyphosis(TLK) at T12-L2, lumbar lordosis(LL) at L1-S1, pelvic tilt(PT), pelvic incidence(PI), and sagittal vertical axis(SVA). The Timed Up and Go (TUG) test was used to measure walking ability. Patients were evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS) part III, and bone mineral density (BMD) scans.

Results

Nineteen patients (59%) had spinal deformity and imbalance within the following classifications: thoracic scoliosis, 1; thoracic kyphosis, 2; lumbar scoliosis, 15; Pisa syndrome, 3; camptocormia, 2. Mean values were 20.0° CA for scoliosis, 42.3° TK, 14.8° TLK, 26.7° LL, 20.8° PT, 48.8° PI, and 66.4 mm SVA. The mean TUG score was 13.9s. The UPDRS III mean was 36.6±24.5 points. Mean BMD was 0.856 g/cm² at lumbar L2-4 and 0.585 g/cm² at the femoral neck. UPDRS part III (P<0.001), LL (P<0.05), and femoral neck BMD (P<0.05) significantly correlated to TUG test results.

Conclusions

Distinct from the movement disorders of PD (UPDRS III), loss of normal LL and loss of BMD at the femoral neck were shown to be correlated with diminished walking ability (TUG test) in PD patients. When UPDRS improved in response to L-dopa, walking ability improved. In addition to any PD-specific interventions that contribute to the maintenance of ambulation, interventions specific to the restoration of LL, as well as early treatment for osteoporosis may positively affect HRQOL in PD.

Bone Mineral Density, TBS, and Body Composition Indexes in Ukrainian Men with Parkinson's Disease

INTRODUCTION

Current research studies demonstrate the changes of bone mineral density (BMD) in subjects with Parkinson's disease (PD); however, data about bone quality and body composition (BC) indexes are insufficient. The aim of the study was to assess the parameters of BMD, ВС, and trabecular bone score (TBS) in PD males.

MATERIALS AND METHODS

We performed a cross-sectional case-control research design and examined 76 males aged 50-77 years old, who were divided into two groups: first group including men without PD (n=38) and the second group including subjects with PD (n=38). Disease duration was at least 5 years; all PD participants were at levodopa therapy. BMD of lumbar spine, femoral neck, total femur, radius, and total body and TBS L l-L 4 were measured using the DXA method. Whole-body DXA measures were also used for the study of total, lean, and fat masses, skeletal muscle index (SMI), appendicular lean mass index (ALMI), and fat mass index (FMI).

RESULTS

Our study showed an increased incidence of osteoporosis and significantly lower total body BMD (respectively, 1.20 ± 0.13 and 1.26 ± 0.10 g/cm2, p=0.05), but not lumbar spine and femoral neck BMDs, and higher TBS value in PD men comparing to the control group (respectively, 1.33 ± 0.12 and 1.22 ± 0.18 un., p=0.005). Also, we established significantly decreased lower extremities BMD indexes, but not upper extremities, spine, and trunk BMDs in PD males. The femoral neck, proximal femur, and lower extremities BMD indexes in PD men were reliably lower at the side of predominance of clinical symptoms. Parameters of appendicular lean mass and ALMI in PD males were reliably higher, but fat mass values and FMI were lower compared to the control group in the absence of significant differences in lean mass values and SMI in weight-matched control.

CONCLUSION

Due to low BMD values, changes in BC are present in PD males, and appropriate screening and preventive strategies should be instigated to maintain bone health in PD subjects.

Overexpression of Wild-Type Human Alpha-Synuclein Causes Metabolism Abnormalities in Thy1-aSYN Transgenic Mice

Parkinson’s disease is a progressive neurodegenerative disorder characterized by loss of dopaminergic neurons, pathological accumulation of alpha-synuclein and motor symptoms, but also by non-motor symptoms. Metabolic abnormalities including body weight loss have been reported in patients and could precede by several years the emergence of classical motor manifestations. However, our understanding of the pathophysiological mechanisms underlying body weight loss in PD is limited. The present study investigated the links between alpha-synuclein accumulation and energy metabolism in transgenic mice overexpressing Human wild-type (WT) alpha-synuclein under the Thy1 promoter (Thy1-aSYN mice). Results showed that Thy1-aSYN mice gained less body weight throughout life than WT mice, with significant difference observed from 3 months of age. Body composition analysis of 6-month-old transgenic animals showed that body mass loss was due to lower adiposity. Thy1-aSYN mice displayed lower food consumption, increased spontaneous activity, as well as a reduced energy expenditure compared to control mice. While no significant change in glucose or insulin responses were observed, Thy1-aSYN mice had significantly lower plasmatic levels of insulin and leptin than control animals. Moreover, the pathological accumulation of alpha-synuclein in the hypothalamus of 6-month-old Thy1-aSYN mice was associated with a down-regulation of the phosphorylated active form of the signal transducer and activator of transcription 3 (STAT3) and of Rictor (the mTORC2 signaling pathway), known to couple hormonal signals with the maintenance of metabolic and energy homeostasis. Collectively, our results suggest that (i) metabolic alterations are an important phenotype of alpha-synuclein overexpression in mice and that (ii) impaired STAT3 activation and mTORC2 levels in the hypothalamus may underlie the disruption of feeding regulation and energy metabolism in Thy1-aSYN mice.

Enhancers active in dopamine neurons are a primary link between genetic variation and neuropsychiatric disease

Enhancers function as DNA logic gates and may control specialized functions of billions of neurons. Here we show a tailored program of noncoding genome elements active in situ in physiologically distinct dopamine neurons of the human brain. We found 71,022 transcribed noncoding elements, many of which were consistent with active enhancers and with regulatory mechanisms in zebrafish and mouse brains. Genetic variants associated with schizophrenia, addiction, and Parkinson's disease were enriched in these elements. Expression quantitative trait locus analysis revealed that Parkinson's disease-associated variants on chromosome 17q21 cis-regulate the expression of an enhancer RNA in dopamine neurons. This study shows that enhancers in dopamine neurons link genetic variation to neuropsychiatric traits.

Osteocalcin Ameliorates Motor Dysfunction in a 6-Hydroxydopamine-Induced Parkinson's Disease Rat Model Through AKT/GSK3β Signaling

Osteoblasts derived osteocalcin (OCN) is recently reported to be involved in dopaminergic neuronal development. As dopaminergic neuronal injury in the substantia nigra (SN) is a pathological hallmark of Parkinson’s disease (PD), we investigated whether OCN could exert protective effects on 6-hydroxydopamine (6-OHDA)-induced PD rat model. Our data showed that the OCN level in the cerebrospinal fluid (CSF) in PD rat models was significantly lower than that in controls. Intervention with OCN could improve the behavioral dysfunction in PD rat models and reduce the tyrosine hydroxylase (TH) loss in the nigrostriatal system. In addition, OCN could inhibit the astrocyte and microglia proliferation in the SN of PD rats. In vitro studies showed that OCN significantly ameliorated the neurotoxicity of 6-OHDA through the AKT/GSK3β signaling pathway. In summary, OCN plays a protective role against parkinsonian neurodegeneration in the PD rat model, suggesting a potential therapeutic use of OCN in PD.

Functional results and patient satisfaction after long fusion for spinal deformity in Parkinson's disease

BACKGROUND

Patients with Parkinson's disease often present abnormal posture or severe sagittal malalignment, causing significant disability. Surgical fusion is these cases shows high rates of complications, but may nevertheless provide functional benefit; however, this remains to be assessed.

HYPOTHESIS

Long fusion for patients with Parkinson's disease and postural disorder could alleviate disability despite the high risk of complications.

METHODS

We retrospectively reviewed 18 Parkinson patients treated by long fusion for spinal deformity. Functional results on the Oswestry Disability Index (ODI) and patient satisfaction were assessed at a minimum 2 years' follow-up. Predictive factors for good outcome were analyzed.

RESULTS

Median follow-up was 44.4 months (IQR, 36-62.4 months). ODI showed significant improvement, from 64 (IQR, 59-77) preoperatively to 49 (IQR, 40-57) at last follow-up (p=0.0014). Fifteen patients (83%) were very satisfied (n=5) or satisfied (n=10) with the procedure. On multivariate analysis, only age was significantly associated with improvement in ODI at last follow-up (estimate: -9.8; p=0.5).

DISCUSSION

Although long spinal fusion involves a high risk of complications in Parkinson's patients, the improvement in autonomy and patient satisfaction should be borne in mind before rejecting surgery, especially with motivated patients.

LEVEL OF EVIDENCE

IV.

Surgical treatment of spinal disorders in Parkinson's disease

PURPOSE

Most patients suffering from Parkinson's disease (PD) exhibit alterations in the posture, which can in several cases give rise to spine deformities, both in the sagittal and the coronal plane. In addition, degenerative disorders of the spine frequently associated to PD, such as spinal stenosis and sagittal instability, can further impact the quality of life of the patient. In recent years, spine surgery has been increasingly performed, with mixed results. The aim of this narrative review is to analyze the spinal disorders associated to PD, and the current evidence about their surgical treatment.

METHODS

Narrative review.

RESULTS

Camptocormia, i.e., a pronounced flexible forward bending of the trunk with 7% prevalence, is the most reported sagittal disorder of the spine. Pisa syndrome and scoliosis are both common and frequently associated. Disorders to the spinopelvic alignment were not widely investigated, but a tendency toward a lower ability of PD patients to compensate the sagittal malalignment with respect to non-PD elderly subjects with imbalance seems to emerge. Spine surgery in PD patients showed high rates of complications and re-operations.

CONCLUSIONS

Disorders of the posture and spinal alignment, both in the sagittal and in the coronal planes, are common in PD patients, and have a major impact on the quality of life. Outcomes of spine surgery are generally not satisfactory, likely mostly due to muscle dystonia and poor bone quality. Knowledge in this field needs to be consolidated by further clinical and basic science studies. These slides can be retrieved under Electronic Supplementary Material.

Hip fractures and Parkinson's disease: A case series

There are no specific guidelines for treating Parkinson's disease patients who present with a hip fracture. Here we present a large cohort of patients with Parkinson's disease who suffered hip fractures. Our aim was to assess for differences between a Parkinson's disease population and a non-Parkinson's disease population with hip fractures and make recommendations on management guidelines. We performed a comprehensive analysis of prospectively collected data on all patients with hip fracture who were admitted into our department over a period of 29 years. In total 9225 patients with hip fractures were included in this study, 452 (4.9%) patients had Parkinson's disease. The mobility scores were worse pre- and post-operatively in the Parkinson's group as were mini-mental scores and ASA grade. Post-operative complications were similar between the two groups, with no difference in dislocation rate or wound complications. However, other outcomes including mobility and mortality rate at 1year were worse in the Parkinson's group. These patients also had a longer hospital stay and were more likely to be immobile and discharged to an institution. We recommend that Parkinson's disease patients should be assessed more thoroughly in the peri-operative period and arrangement for rehab and discharge planning should commence as soon as possible following admission. The consent process should reflect longer hospital stays, worse mobility, higher mortality and increased likelihood of discharge to institution but concern over increased complications, specifically dislocation was not evident in our data.

Alpha-synuclein, epigenetics, mitochondria, metabolism, calcium traffic, & circadian dysfunction in Parkinson's disease. An integrated strategy for management

The motor deficits which characterise the sporadic form of Parkinson's disease arise from age-related loss of a subset of dopamine neurons in the substantia nigra. Although motor symptoms respond to dopamine replacement therapies, the underlying disease process remains. This review details some features of the progressive molecular pathology and proposes deployment of a combination of nutrients: R-lipoic acid, acetyl-l-carnitine, ubiquinol, melatonin (or receptor agonists) and vitamin D3, with the collective potential to slow progression of these features. The main nutrient targets include impaired mitochondria and the associated oxidative/nitrosative stress, calcium stress and impaired gene transcription induced by pathogenic forms of alpha- synuclein. Benefits may be achieved via nutrient influence on epigenetic signaling pathways governing transcription factors for mitochondrial biogenesis, antioxidant defences and the autophagy-lysosomal pathway, via regulation of the metabolic energy sensor AMP activated protein kinase (AMPK) and the mammalian target of rapamycin mTOR. Nutrients also benefit expression of the transcription factor for neuronal survival (NR4A2), trophic factors GDNF and BDNF, and age-related calcium signals. In addition a number of non-motor related dysfunctions in circadian control, clock genes and associated metabolic, endocrine and sleep-wake activity are briefly addressed, as are late-stage complications in respect of cognitive decline and osteoporosis. Analysis of the network of nutrient effects reveals how beneficial synergies may counter the accumulation and promote clearance of pathogenic alpha-synuclein.

Vitamin D supplementation

Vitamin D testing and supplementation is of great interest to neurologists and their patients. Recommended nutritional intakes of vitamin D in the UK remain focused on bone health, despite increasing evidence for a role outside this area. Here we discuss how neurologists might approach vitamin D testing and supplementation, focusing on two conditions associated with vitamin D deficiency that have an increased risk of downstream complications resulting from these: multiple sclerosis and epilepsy. We set out a rationale for testing serum 25-hydroxyvitamin D concentrations and discuss our personal practice in terms of supplementation, with evidence where available.

Management of Spinal Conditions in Patients With Parkinson Disease

Parkinson disease (PD) is increasingly prevalent in the aging population. Spine disorders in patients with PD may be degenerative in nature or may arise secondary to motor effects related to the parkinsonian disease process. Physicians providing care for patients with PD and spine pathologies must be aware of several factors that affect treatment, including the patterns of spinal deformity, complex drug interactions, and PD-associated osteoporosis. Following spine surgery, complication rates are higher in patients with PD than in those without the disease. Literature on spine surgery in this patient population is limited by small cohort size, the heterogeneous patient population, and variable treatment protocols. However, most studies emphasize the need for preoperative optimization of motor control with appropriate medications and deep brain stimulation, as well as consultation with a movement disorder specialist. Future studies must control for confounding variables, such as the type of surgery and PD severity, to improve understanding of spinal pathology and treatment options in this patient population.

Fragility Fractures and Parkinsonism: Relationship of Fractures with Demography, Severity and Predictors of Adverse Outcomes

Background: The risk of falls is higher in patients with Parkinsonism (PwP) as compared to other older adults, leading to adverse outcomes including fragility fractures. Osteoporosis is under-recognised and the current prevalence of fragility fractures is not well-studied. The objectives of this study are to determine the prevalence of fragility fractures in PwP, to measure the relationship of fractures with demography, severity and to measure predictors of adverse outcomes in this population. Method/Description: This was a retrospective observational cohort study based on the analysis of existing data for all the patients attending Caerphilly Movement Disorder Clinic. Information on demographics, the severity of Parkinsonism and fragility fractures was extracted electronically from the clinical workstation, clinic letters and coding from January 2015 to October 2016. Results: 397 people (mean age = 77.1 ± 9.4, 46% females) were studied. Of these, 77% (306/397) had Parkinsonism and 80% (244/306) had idiopathic Parkinson’s disease (PD). The mean Hoehn & Yahr Score at the time assessment was 3.09 ± 1.16. Additionally, 23.5% (72/306) were deemed to have osteoporosis based on the radiological evidence of fragility fractures. The PwP who sustained fractures were comparatively older (80.4 ± 12.1) and 70% (50/72) were females. The most common site for fractures was vertebral (47.2%; 34/72). Also, 22.2% of the sample (16/72) had suffered a fragility fracture before the diagnosis of PD. However, a majority (77.8%; 56/72) had sustained a fracture during the course of PD with a mean lapse of 6 years (range = 0–13 years) from initial diagnosis. Only 40% (29/72) of patients were prescribed osteoporosis drugs as per guidelines. There is a significant correlation of advancing age, severity and duration of PD with fragility fractures. The single best predictor of mortality is severity of PD, followed by age and fractures. Conclusions: There is a high prevalence of fragility fractures in patients attending movement disorder clinics, although 60% do not receive evidence-based medical treatment for the underlying osteoporosis. The prevalence of fragility fractures is positively correlated with the duration and severity of PD. We acknowledge the relatively small sample size as the study’s limitation.

Neuroendocrine abnormalities in Parkinson's disease

Neuroendocrine abnormalities are common in Parkinson's disease (PD) and include disruption of melatonin secretion, disturbances of glucose, insulin resistance and bone metabolism, and body weight changes. They have been associated with multiple non-motor symptoms in PD and have important clinical consequences, including therapeutics. Some of the underlying mechanisms have been implicated in the pathogenesis of PD and represent promising targets for the development of disease biomarkers and neuroprotective therapies. In this systems-based review, we describe clinically relevant neuroendocrine abnormalities in Parkinson's disease to highlight their role in overall phenotype. We discuss pathophysiological mechanisms, clinical implications, and pharmacological and non-pharmacological interventions based on the current evidence. We also review recent advances in the field, focusing on the potential targets for development of neuroprotective drugs in Parkinson's disease and suggest future areas for research.

Pathogenic LRRK2 variants are gain-of-function mutations that enhance LRRK2-mediated repression of β-catenin signaling

BACKGROUND

LRRK2 mutations and risk variants increase susceptibility to inherited and idiopathic Parkinson's disease, while recent studies have identified potential protective variants. This, and the fact that LRRK2 mutation carriers develop symptoms and brain pathology almost indistinguishable from idiopathic Parkinson's disease, has led to enormous interest in this protein. LRRK2 has been implicated in a range of cellular events, but key among them is canonical Wnt signalling, which results in increased levels of transcriptionally active β-catenin. This pathway is critical for the development and survival of the midbrain dopaminergic neurones typically lost in Parkinson's disease.

METHODS

Here we use Lrrk2 knockout mice and fibroblasts to investigate the effect of loss of Lrrk2 on canonical Wnt signalling in vitro and in vivo. Micro-computed tomography was used to study predicted tibial strength, while pulldown assays were employed to measure brain β-catenin levels. A combination of luciferase assays, immunofluorescence and co-immunoprecipitation were performed to measure canonical Wnt activity and investigate the relationship between LRRK2 and β-catenin. TOPflash assays are also used to study the effects of LRRK2 kinase inhibition and pathogenic and protective LRRK2 mutations on Wnt signalling. Data were tested by Analysis of Variance.

RESULTS

Loss of Lrrk2 causes a dose-dependent increase in the levels of transcriptionally active β-catenin in the brain, and alters tibial bone architecture, decreasing the predicted risk of fracture. Lrrk2 knockout cells display increased TOPflash and Axin2 promoter activities, both basally and following Wnt activation. Consistently, over-expressed LRRK2 was found to bind β-catenin and repress TOPflash activation. Some pathogenic LRRK2 mutations and risk variants further suppressed TOPflash, whereas the protective R1398H variant increased Wnt signalling activity. LRRK2 kinase inhibitors affected canonical Wnt signalling differently due to off-targeting; however, specific LRRK2 inhibition reduced canonical Wnt signalling similarly to pathogenic mutations.

CONCLUSIONS

Loss of LRRK2 causes increased canonical Wnt activity in vitro and in vivo. In agreement, over-expressed LRRK2 binds and represses β-catenin, suggesting LRRK2 may act as part of the β-catenin destruction complex. Since some pathogenic LRRK2 mutations enhance this effect while the protective R1398H variant relieves it, our data strengthen the notion that decreased canonical Wnt activity is central to Parkinson's disease pathogenesis.

Long-term risk of falls in an incident Parkinson's disease cohort: the Norwegian ParkWest study

The objective of this study is to examine the frequency, development, concomitants, and risk factors of falls in a population-based incident Parkinson's disease (PD) cohort. One hundred eighty-one drug-naïve patients with incident PD and 173 normal controls recruited from the Norwegian ParkWest study were prospectively monitored over 7 years. Information on falls was obtained biannually from patients, and at baseline and after 1, 3, 5, and 7 years of follow-up in control subjects. Generalized estimating equation models for correlated data were applied to investigate concomitant features of falls and risk factors for incident falls during 7 years of follow-up in PD. Overall, 64.1% of patients reported falling during the study period. The 7-year cumulative incidence of falls in non-falling patients at baseline (n = 153) was 57.5%, with a relative risk to controls of at least 3.1 (95% confidence interval 1.5-6.3; p < 0.002). Significant concomitants of falls in patients during the study period were higher age, Unified PD Rating Scale motor score, postural instability and gait difficulties (PIGD) phenotype, dementia, and follow-up time. Higher age at baseline, PIGD phenotype at 1-year visit, and follow-up time were independent risk factors for incident falls during follow-up. Nearly two-thirds of patients in the general PD population experience falls within 7 years of diagnosis, representing a more than threefold increased risk compared to age- and gender-matched controls. Patients with higher age at baseline and early PIGD have the greatest risk of falling and may, therefore, be the prime target of specialized assessment and treatment interventions.

Comorbid Parkinson's disease, falls and fractures in the 2010 National Emergency Department Sample

INTRODUCTION

Parkinson's disease (PD) is a progressive, neurodegenerative disorder of multifactorial etiology affecting ∼1% of older adults. Research focused on linking PD to falls and bone fractures has been limited in Emergency Department (ED) settings, where most injuries are identified. We assessed whether injured U.S. ED admissions with PD diagnoses were more likely to exhibit comorbid fall- or non-fall related bone fractures and whether a PD diagnosis with a concomitant fall or bone fracture is linked to worse prognosis.

METHODS

We performed secondary analyses of 2010 Healthcare Utilization Project National ED Sample from 4,253,987 admissions to U.S. EDs linked to injured elderly patients. ED discharges with ICD-9-CM code (332.0) were identified as PD and those with ICD-9-CM code (800.0-829.0) were used to define bone fracture location. Linear and logistic regression models were constructed to estimate slopes (B) and odds ratios (OR) with 95% confidence intervals (CI).

RESULTS

PD admissions had 28% increased adjusted prevalence of bone fracture. Non-fall injuries showed stronger relationship between PD and bone fracture (OR_adj = 1.33, 95% CI: 1.22-1.45) than fall injuries (OR_adj = 1.06, 95% CI: 1.01-1.10). PD had the strongest impact on hospitalization length when bone fracture and fall co-occurred, and total charges were directly associated with PD only for fall injuries. Finally, PD status was not related to in-hospital death in this population.

CONCLUSION

Among injured U.S. ED elderly patient visits, those with PD had higher bone fracture prevalence and more resource utilization especially among fall-related injuries. No association of PD with in-hospital death was noted.

A quality improvement initiative on the management of osteoporosis in older people with Parkinsonism

The risk of falls is higher in patients with people with Parkinsonism (PwP) compared to those without Parkinsonism, and leads to adverse outcomes including fragility fractures. Osteoporosis is under-recognised, and the prevalence of fragility fractures in not well studied. The primary aim of this project is for 100% of new patient referrals to, and 80% of follow up patients within the movement disorder (MD) service with osteoporosis to be treated in accordance with evidence based osteoporosis guidance.

Routinely captured information regarding demographics and fragility fractures was retrospectively extracted from the clinical workstation, clinic letters, and clinical coding between July and November 2015. The prevalence of fragility fracture was 22.6% (68/300), and only 40% (27/68) were on appropriate treatment for osteoporosis.

A quality improvement (QI) methodology based on the model of improvement, Plan-Do-Study-Act (PDSA) cycles were used, and a monthly multidisciplinary team (MDT) meeting was introduced.

This QI initiative has shown that MDT input can reduce referrals to physiotherapists; and also 100% of new patients, and 91% of follow up patients received evidence based osteoporosis treatment.

Risk Factors, Epidemiology and Treatment Strategies for Metabolic Bone Disease in Patients with Neurological Disease

Metabolic bone disease is a major public health concern, especially when it manifests as hip fracture which carries significant morbidity and mortality. Individuals with neurological disease are at higher risk of osteopenia, osteoporosis and fragility fracture compared to age-matched controls, yet this is under-appreciated by these patients. Clinician attention to this topic is therefore of importance and should address the bone health of men as well as women, a group in whom it may be an under-recognised problem. Evidence for optimal management of bone health in neurological disease remains to be defined, but a growing literature provides some useful guidance. This review focuses on two conditions, multiple sclerosis and Parkinson's disease, where research has been active over recent years. In neuroinflammation, shared immunological pathways between bone and brain are a current domain of interest and it will be intriguing to interrogate the action of emerging immunotherapies on these dual compartments.

Comparing the Incidence of Falls/Fractures in Parkinson's Disease Patients in the US Population

Patients with Parkinson’s disease (PD) may experience falls and/or fractures as a result of disease symptoms. There are limited data available from long-term studies estimating the incidence of falls/fractures in patients with PD. The objective was to compare the incidence rate of falls/fractures in PD patients with non-PD patients in a US population. This was a retrospective study using a US-based claims database (Truven Health MarketScan^®) that compared the incidence rate of falls/fractures in PD subjects with non-PD subjects. The study period included the 12 months prior to index date (defined as earliest PD diagnosis [International Classification of Diseases, Ninth Revision, Clinical Modification code 332.0]) and a postindex period to the end of data availability. Fractures were defined by inpatient/outpatient claims as a principal or secondary diagnosis and accompanying procedure codes during the postindex period. Incidence rates and 95% CIs for falls/fractures were calculated as the number of events per 10,000 person-years of follow-up using negative binomial or Poisson regression models. Twenty-eight thousand two hundred and eighty PD subjects were matched to non-PD subjects for the analysis (mean [SD] age, 71.4 [11.8] years; 53% male). A higher incidence rate (adjusted for comorbidities and medications) of all fall/fracture cases and by fall and fracture types was observed for PD subjects versus non-PD subjects; the overall adjusted incidence rate ratio comparing PD to non-PD subjects was 2.05; 95% CI, 1.88–2.24. The incidence rate of falls/fractures was significantly higher in subjects with PD compared with non-PD subjects in a US population.

Bone mass and vitamin D levels in Parkinson's disease: is there any difference between genders?

[Purpose] The aim of this study was to determine the bone mineral density, vitamin D level, and frequencies of osteopenia and osteoporosis in patients with Parkinson's disease and to compare male and female patients with the controls separately. [Subjects and Methods] One hundred fifteen Parkinson's disease patients (47 males, 68 females; age range: 55-85 years) and 117 age- and gender-matched controls (47 males, 70 females) were enrolled in the study. Bone mineral density measured by dual-energy X-ray absorptiometry and serum D vitamin levels of each participant were recorded. [Results] The mean lumbar spine, femur neck, and total femur bone mineral density levels, T-scores, and vitamin D levels were found to be significantly lower in Parkinson's disease patients in both genders. Furthermore, osteoporosis rates were found be significantly higher only in female Parkinson's disease patients compared with female controls. [Conclusion] Data from the present study revealed that while osteoporosis was significantly higher only in female Parkinson's disease patients, all Parkinson's disease patients had lower bone mineral density scores and vitamin D levels compared with the controls regardless of gender, suggesting that clinicians should pay attention to the osteoporosis risk in Parkinson's disease and that adequate preventive measures should be taken in order to limit the future risk due to osteoporotic fractures.

Falls, fractures and bone density in Parkinson's disease - a cross-sectional study

AIM

Evidence suggests that falls and associated bone fractures are more frequent in patients suffering from Parkinson's disease (PD) than in the general population. In this cross-sectional study we evaluated the clinical and biochemical characteristics that are associated to falls, fractures and bone health in a population of PD subjects.

MATERIALS AND METHODS

Forty-two consecutive subjects suffering from idiopathic PD (mild-to-moderate severity) with/without falls in the previous year were included. They were characterized as regards functional independence, balance, fear of falling, bone density (ultrasound densitometry) and plasma levels of vitamin D. Twenty-one age- and sex-matched healthy subjects were evaluated as controls.

RESULTS

We detected a greater degree of osteoporosis in PD subjects as compared to controls, more pronounced in males than in females (Z-score: M -3.8 ± 1.6, F -2.28 ± 0.92, p = 0.0006). A positive correlation was found between independence levels and bone density or vitamin D levels. Twenty seven patients (64%) reported falls in the previous year. These were associated to post-traumatic fractures in 16 subjects (59% of fallers). Women fell more than men (fallers: 20 F/7 M; non fallers: 4 F/11 M, χ² test p = 0.02), although the occurrence of post-traumatic fractures among fallers did not differ between sexes (F 11/9, M 5/2, χ² test p > 0.05). Fallers with post-traumatic fractures showed higher degrees of motor impairment.

CONCLUSIONS

These findings confirm that falls and osteoporosis represent major health issues in PD, already in the middle stages of disease.

Postural, Bone, and Joint Disorders in Parkinson's Disease

Background

Stooped posture was mentioned in the original description of the characteristic features of Parkinson's disease (PD). Since then, a variety of postural, bone, and joint problems have become recognized as common aspects of the illness and deserve attention.

Methods

A Medline literature search for the period from 1970 to 2016 was performed to identify articles relevant to this topic. Keywords for the search included posture, spine, bone disorders, fractures, joint disorders, kyphosis, scoliosis, stooping, camptocormia, Pisa syndrome, frozen shoulder, anterocollis, dropped head syndrome, and pain in combination with PD. The articles were then reviewed to summarize clinical features, frequency, impact, pathophysiology, and treatment options for these conditions.

Results

Postural disorders (kyphoscoliosis, camptocormia, Pisa syndrome, dropped head syndrome), bone mineralization disorders (osteoporosis, bone fractures), and joint disorders (frozen shoulder, dystonia involving joints, joint pain) are often seen in association with PD. Treatment options for these conditions are varied and may include medications, physical therapy, or surgical interventions.

Conclusions

Posture, bone, and joint disorders are common in patients with PD; they often produce added disability, and they may be treatable.

Network Analysis Implicates Alpha-Synuclein (Snca) in the Regulation of Ovariectomy-Induced Bone Loss

The postmenopausal period in women is associated with decreased circulating estrogen levels, which accelerate bone loss and increase the risk of fracture. Here, we gained novel insight into the molecular mechanisms mediating bone loss in ovariectomized (OVX) mice, a model of human menopause, using co-expression network analysis. Specifically, we generated a co-expression network consisting of 53 gene modules using expression profiles from intact and OVX mice from a panel of inbred strains. The expression of four modules was altered by OVX, including module 23 whose expression was decreased by OVX across all strains. Module 23 was enriched for genes involved in the response to oxidative stress, a process known to be involved in OVX-induced bone loss. Additionally, module 23 homologs were co-expressed in human bone marrow. Alpha synuclein (Snca) was one of the most highly connected “hub” genes in module 23. We characterized mice deficient in Snca and observed a 40% reduction in OVX-induced bone loss. Furthermore, protection was associated with the altered expression of specific network modules, including module 23. In summary, the results of this study suggest that Snca regulates bone network homeostasis and ovariectomy-induced bone loss.

Shoulder arthroplasty in patients with Parkinson's disease is associated with increased complications

BACKGROUND

Case series suggest a higher postoperative complication rate after shoulder arthroplasty in patients with Parkinson's disease (PD). The purpose of this study was to evaluate the perioperative complications in patients with PD undergoing conventional total shoulder arthroplasty (TSA), reverse shoulder arthroplasty (RSA), and shoulder hemiarthroplasty (HA).

METHODS

Patients with PD who underwent TSA, RSA, or HA were identified in a national insurance database and then matched to controls without a diagnosis of PD based on age, gender, obesity, diabetes, and tobacco use. Complications were assessed, including infection, dislocation, revision, stiffness, fracture, component loosening, and systemic complications.

RESULTS

The final study cohorts included 3390 TSA patients with PD and 47,034 matched TSA controls; 809 RSA patients with PD and 14,262 matched controls; and 2833 HA patients with PD and 38,850 matched controls. PD was associated with significant higher rates of infection (odds ratio [OR], 1.5, 1.7, 1.5, respectively), dislocation (OR, 2.5, 2.0, 2.8, respectively), revision arthroplasty (OR, 1.7, 1.8, 1.4, respectively), and systemic complications (OR, 1.4, 1.7, 1.3, respectively) after all 3 types of shoulder arthroplasty and with higher rates of periprosthetic fracture after conventional TSA (OR, 1.5) and shoulder HA (OR, 1.5). Component loosening was also more commonly noted in patients with PD after conventional TSA (OR, 1.5) and HA (OR, 1.9).

CONCLUSION

PD is associated with increased rates of infection, dislocation, revision shoulder arthroplasty, fracture, component loosening, and systemic complications after conventional TSA, RSA, and shoulder HA.

Lower Bone Mineral Density in Patients with Parkinson's Disease: A Cross-Sectional Study from Chinese Mainland

KEY POINTS

Significantly lower BMD in PD compared to healthy subjects in both genders.Less than 35 mg(2)/dl(2) of Ca-P product in >80% of PD patients.Significant correlations between BMD and severity of PD.Lower BMD at H&Y stage III/IV than that at H&Y stage I/II.

OBJECTIVES

Although several lines of evidence have suggested that patients with Parkinson's disease (PD) have a higher risk of osteoporosis and fracture, the association between bone mineral density (BMD) and severity of PD patients is unknown.

METHODS

We performed a cross-sectional study of 54 patients with PD and 59 healthy age-matched controls. Multiple clinical scales were used to evaluate the severity of PD, and serum levels of calcium, phosphorus, and homocysteine were measured to determine BMD's association with PD severity.

RESULTS

BMD in PD patients was significantly lower than that in healthy controls. The BMD scores of the spine, femoral neck (FN), and hip were lower in females than in males in the healthy group. In the PD group, BMD in the hip was significantly lower in females compared to males. There was a negative correlation between daily l-DOPA dosage and BMD in the spine and hip in the PD group, while BMD in the spine, neck, and hip was significantly correlated with severity of PD. Besides, we found that among the lumbar spine (LS), FN, and hip, bone loss in the LS was the most severe in PD patients based on the T-scores.

CONCLUSION

Our findings support the hypothesis that patients with PD have a higher risk of osteoporosis, and that low BMD in the spine, FN, and hip may indirectly reflect the severity of PD. Our findings have prompted us to pay more attention to osteoporosis in the LS in Chinese PD patients.