Osteoporosis: A Hidden Nonmotor Face of Parkinson's Disease

The first cross-sectional comparative observational study of sexual dysfunction in Emirati and non-Emirati Parkinson's disease patients (EmPark-SD) in the United Arab Emirates

Sexual dysfunction (SD) is a common non-motor symptom in people with Parkinson's disease (PD) yet underreported and undertreated specifically in many ethnic PD groups because of religious, social and personal perceptions. We conducted the first single-centre cross-sectional study in the United Arab Emirates of SD in 513 consecutive patients who agreed to complete the survey questionnaires. Data was collected on SD using the Nonmotor Symptoms Scale (NMSS), Index of Erectile Function, and Female Sexual Function Index. Our results show that the non-Emirati group had higher NMSS-SD scores than the Emirati group. SD was reported independent of ethnicity, race and disease stage (p < 0.001). SD correlated with worsening quality of life (p < 0.001) and anxiety domain, especially in young PD patients (p < 0.001). Our data concludes that there is no significant difference in SD between different ethnicity groups, contrary to common perception. SD appears to be underreported in this population and needs addressing using culturally sensitive bespoke counselling.

Medication Prescription Policy for US Veterans With Metastatic Castration-Resistant Prostate Cancer: Causal Machine Learning Approach

BACKGROUND

Prostate cancer is the second leading cause of death among American men. If detected and treated at an early stage, prostate cancer is often curable. However, an advanced stage such as metastatic castration-resistant prostate cancer (mCRPC) has a high risk of mortality. Multiple treatment options exist, the most common included docetaxel, abiraterone, and enzalutamide. Docetaxel is a cytotoxic chemotherapy, whereas abiraterone and enzalutamide are androgen receptor pathway inhibitors (ARPI). ARPIs are preferred over docetaxel due to lower toxicity. No study has used machine learning with patients' demographics, test results, and comorbidities to identify heterogeneous treatment rules that might improve the survival duration of patients with mCRPC.

OBJECTIVE

This study aimed to measure patient-level heterogeneity in the association of medication prescribed with overall survival duration (in the form of follow-up days) and arrive at a set of medication prescription rules using patient demographics, test results, and comorbidities.

METHODS

We excluded patients with mCRPC who were on docetaxel, cabaxitaxel, mitoxantrone, and sipuleucel-T either before or after the prescription of an ARPI. We included only the African American and white populations. In total, 2886 identified veterans treated for mCRPC who were prescribed either abiraterone or enzalutamide as the first line of treatment from 2014 to 2017, with follow-up until 2020, were analyzed. We used causal survival forests for analysis. The unit level of analysis was the patient. The primary outcome of this study was follow-up days indicating survival duration while on the first-line medication. After estimating the treatment effect, a prescription policy tree was constructed.

RESULTS

For 2886 veterans, enzalutamide is associated with an average of 59.94 (95% CI 35.60-84.28) more days of survival than abiraterone. The increase in overall survival duration for the 2 drugs varied across patient demographics, test results, and comorbidities. Two data-driven subgroups of patients were identified by ranking them on their augmented inverse-propensity weighted (AIPW) scores. The average AIPW scores for the 2 subgroups were 19.36 (95% CI -16.93 to 55.65) and 100.68 (95% CI 62.46-138.89). Based on visualization and t test, the AIPW score for low and high subgroups was significant (P=.003), thereby supporting heterogeneity. The analysis resulted in a set of prescription rules for the 2 ARPIs based on a few covariates available to the physicians at the time of prescription.

CONCLUSIONS

This study of 2886 veterans showed evidence of heterogeneity and that survival days may be improved for certain patients with mCRPC based on the medication prescribed. Findings suggest that prescription rules based on the patient characteristics, laboratory test results, and comorbidities available to the physician at the time of prescription could improve survival by providing personalized treatment decisions.

Causal effects of osteoporosis on structural changes in specific brain regions: a Mendelian randomization study

Observational studies have reported that osteoporosis is associated with cortical changes in the brain. However, the inherent limitations of observational studies pose challenges in eliminating confounding factors and establishing causal relationships. And previous observational studies have not reported changes in specific brain regions. By employing Mendelian randomization, we have been able to infer a causal relationship between osteoporosis and a reduction in the surficial area (SA) of the brain cortical. This effect is partially mediated by vascular calcification. We found that osteoporosis significantly decreased the SA of global brain cortical (β = -1587.62 mm2, 95%CI: -2645.94 mm2 to -529.32 mm2, P = 0.003) as well as the paracentral gyrus without global weighted (β = - 19.42 mm2, 95%CI: -28.90 mm2 to -9.95 mm2, P = 5.85 × 10-5). Furthermore, we estimated that 42.25% and 47.21% of the aforementioned effects are mediated through vascular calcification, respectively. Osteoporosis leads to a reduction in the SA of the brain cortical, suggesting the presence of the bone-brain axis. Vascular calcification plays a role in mediating this process to a certain extent. These findings establish a theoretical foundation for further investigations into the intricate interplay between bone, blood vessels, and the brain.

Addressing Comorbidities in People with Parkinson's Disease: Considerations From An Expert Panel

In the UK, guidance exists to aid clinicians and patients deciding when treatment for Parkinson's disease (PD) should be initiated and which therapies to consider. National Institute for Health and Care Excellence (NICE) guidance recommends that before starting PD treatment clinicians should discuss the following: the patient's individual clinical circumstances; lifestyle; preferences; needs and goals; as well as the potential benefits and harms of the different drug classes. Individualization of medicines and management in PD significantly improves patients' outcomes and quality of life. This article aims to provide simple and practical guidance to help clinicians address common, but often overlooked, co-morbidities. A multi-disciplinary group of PD experts discussed areas where clinical care can be improved by addressing commonly found co-morbidities in people with Parkinson's (PwP) based on clinical experience and existing literature, in a roundtable meeting organized and funded by Bial Pharma UK Ltd. The experts identified four core areas (bone health, cardiovascular risk, anticholinergic burden, and sleep quality) that, if further standardized may improve treatment outcomes for PwP patients. Focusing on anticholinergic burden, cardiac risk, sleep, and bone health could offer a significant contribution to personalizing regimes for PwP and improving overall patient outcomes. Within this opinion-based paper, the experts offer a list of guiding factors to help practitioners in the management of PwP.

Chaudhuri's Dashboard of Vitals in Parkinson's syndrome: an unmet need underpinned by real life clinical tests

We have recently published the notion of the "vitals" of Parkinson's, a conglomeration of signs and symptoms, largely nonmotor, that must not be missed and yet often not considered in neurological consultations, with considerable societal and personal detrimental consequences. This "dashboard," termed the Chaudhuri's vitals of Parkinson's, are summarized as 5 key vital symptoms or signs and comprise of (a) motor, (b) nonmotor, (c) visual, gut, and oral health, (d) bone health and falls, and finally (e) comorbidities, comedication, and dopamine agonist side effects, such as impulse control disorders. Additionally, not addressing the vitals also may reflect inadequate management strategies, leading to worsening quality of life and diminished wellness, a new concept for people with Parkinson's. In this paper, we discuss possible, simple to use, and clinically relevant tests that can be used to monitor the status of these vitals, so that these can be incorporated into clinical practice. We also use the term Parkinson's syndrome to describe Parkinson's disease, as the term "disease" is now abandoned in many countries, such as the U.K., reflecting the heterogeneity of Parkinson's, which is now considered by many as a syndrome.

The Dopamine D1 Receptor Attenuates Titanium Particle-Induced Inhibition of Osteogenesis by Activating the Wnt Signaling Pathway

Periprosthetic osteolysis (PPO), caused by wear particles, has become a major cause of joint replacement failure. Secondary surgery after joint replacement poses a serious threat to public health worldwide. Therefore, determining how to effectively inhibit wear particle-induced PPO has become an urgent issue. Recently, the interaction between osteogenic inhibition and wear particles at the biological interface of the implant has been found to be an important factor in the pathological process. Previous studies have found that the central nervous system plays an important role in the regulation of bone formation and bone remodeling. Dopamine (DA), an important catecholamine neurotransmitter, plays an integral role in the physiological and pathological processes of various tissues through its corresponding receptors. Our current study found that upregulation of dopamine first receptors could be achieved by activating the Wnt/β-catenin pathway, improving osteogenesis in vivo and in vitro, and significantly reducing the inhibition of titanium particle-induced osteogenesis. Overall, these findings suggest that dopamine first receptor (D1R) may be a plausible target to promote osteoblast function and resist wear particle-induced PPO.

Anti-osteoporosis treatments changed body composition in postmenopausal women: A systematic review and meta-analysis

BACKGROUND

Whether the widespread anti-osteoporosis treatments in postmenopausal women also benefit the change of body composition (lean body mass [LBM] and body fat mass [FM]) remains controversial. In order to solve this issue and find out the most effective treatment, we conducted this meta-analysis.

METHODS

We searched the literature, via PubMed, Embase, Scopus, Web of Science, and Cochrane to screen citations from inception to March 26, 2022, for inclusion in this study. Only clinical trials that used anti-osteoporosis treatments in postmenopausal women and displayed the alteration of body composition were included. Stata 14.0 was used for the meta-analysis.

RESULTS

Our meta-analysis results presented that: compared with placebo, hormone replacement therapy (HRT) was associated with increased LBM (standardized mean differences [SMD] = 0.32, 95% confidence interval [CI] = 0.02-0.61) and reduced FM (SMD = -0.30, 95% CI = -0.51 to -0.09) in postmenopausal women. Compared with placebo, physical exercise training showed an effect of decreasing FM (SMD = -0.66, 95% CI = -0.94 to -0.38) but not significant influence LBM (SMD = 1.31, 95% CI = -0.29 to 2.91). The network meta-analysis of our study showed that oral estrogen and progestogen plus exercise (OEPE) treatment might be the most effective anti-osteoporosis treatment (surface under the cumulative ranking curve 99.9) to reduce FM in postmenopausal women.

CONCLUSIONS

anti-osteoporosis treatments, especially HRT, affect body composition. Furthermore, the combination of HRT and exercise training are the most effective treatment to reduce FM while maintaining LBM.

Consecutive Kummell's Disease Combined with Parkinson's Disease and Experienced Internal Fixation Failure: A Case Report and Literature Review

Background

The continuous occurrence of Kummell's disease is extremely rare in clinical practice, and its treatment is difficult. The study aimed to present a rare case of consecutive Kummell's disease combined with Parkinson's disease (PD) and experienced internal fixation failure.

Case presentation

A 69‐year‐old female patient had a history of PD for 10 years, and was treated by posterior decompression, fixation, and fusion because of Kummell's disease of T12 with neurological damage. The patient's back pain and lower limb pain were significantly improved after surgery. Twenty‐two months later, the patient was rehospitalized for Kummell's disease of L4 with neuropathic pain of left lower extremity. She received almost identical surgical procedures as T12 lesion, and the difference was no L4 vertebroplasty preformed due to the fact that the L4 vertebrae collapse was not obvious, the intravertebral vacuum cleft (IVC) range was small, and the pedicle screw fixation strength was high. The pain symptoms were significantly relieved after operation. Unfortunately, there was a complication of internal fixation failure that occurred a month later, and a revision operation was carried out.

Conclusion

Osteoporosis combined with PD may lead patients to become prone to consecutive Kummell's disease, and patients are prone to experience failure of internal fixation. Bone cement filling of vertebral IVC and effective support of anterior vertebral column are very important procedures to ensure the clinical efficacy of treating Kummell's disease.

The Influence of Parkinson's Disease on Outcome and Complication Rate of Reverse Total Shoulder Arthroplasty: A Matched Group Analysis

Parkinson's disease (PD) is associated with a higher complication rate after common orthopedic procedures, such as spinal fusion, knee arthroplasty, or hip arthroplasty. A few reports have also suggested higher complication rates after reverse total shoulder arthroplasty (RTSA). The aim of this study was to assess the outcome and complication profile of patients with RTSA and PD. A total of 17 patients (mean age, 73.9±9.5 years) with PD and RTSA with a minimum follow-up of 2 years were identified on screening of the authors' institutional RTSA database. These patients were compared with a 1:4 matched cohort group of 68 patients (mean age, 73.9±7.9 years) without PD. Complications and revisions for all patients were assessed by review of medical records. Outcome scores included the Constant-Murley score and the Subjective Shoulder Value. At a mean follow-up of 49.5±24 months, statistically significant improvements were obtained in postoperative Subjective Shoulder Value, Constant-Murley score, pain, flexion, abduction, internal rotation, and strength for both groups. However, the control group had significantly greater improvements in flexion, abduction, strength, Subjective Shoulder Value, and Constant-Murley score. Postoperative complications (35% vs 6%; odds ratio, 8.7) and reinterventions (29% vs 1%; odds ratio, 27.9) were substantially greater for patients with PD, with the most frequent complications being fractures of the scapular spine and the acromion. Reverse total shoulder arthroplasty is associated with a significantly higher complication rate and revision rate and an inferior outcome in patients with PD compared with neurologically healthy patients. Indications for RTSA should be carefully evaluated and questioned for patients with PD. [Orthopedics. 2021;44(2):86-91.].

LLLI promotes BMSC proliferation through circRNA_0001052/miR-124-3p

Osteoporosis (OP) is a multifactorial bone disease that occurs worldwide. The treatment of OP is still unsatisfactory. Bone mesenchymal stem cell (BMSC) differentiation is a key process in OP pathogenesis. Low-level laser irradiation (LLLI) has been reported to regulate BMSC proliferation, but the role of circRNAs in the LLLI-based promotion of BMSC proliferation remains unclear. CircRNAs are essential molecular regulators that participate in numerous biological processes and have therapeutic potential. miR-124-3p is an essential microRNA (miRNA), and its expression changes are related to BMSC proliferation ability. In the present study, gain-loss function of experiments demonstrated that circRNA_0001052 could regulate the proliferation of BMSCs by acting as a miR-124-3p sponge through the Wnt4/β-catenin pathway. The results of this study strongly suggest that circRNA_0001052 plays an essential role in BMSC proliferation in response to LLLI treatment, which is a potential therapeutic manipulation with clinical applications.

Bone Mineral Density Loss in Parkinson's Disease: Impact of Clinical Subtypes

Background: This study aimed to compare the BMD status among the clinical subtypes of PD and healthy controls.Methods: Sixty patients with PD and 30 healthy age- and sex-matched controls were included in this study. The patients were divided into postural instability gait difficulty-dominant type (PIGDDT) group and tremor-dominant type (TDT) group based on the Unified Parkinson's Disease Rating Scale (UPDRS) score. BMD was measured using dual-energy X-ray absorptiometry scans in femoral and lumbar regions.Results: The T-scores in femoral and lumbar regions were similar in all groups. The prevalence of osteopenia was higher than the prevalence of osteoporosis in all three groups for femoral regions. The prevalence of osteoporosis in the intertrochanteric region and total femur in the PIGDDT group was higher than in the TDT group and controls. Our data showed a trend toward higher prevalence of osteoporosis in the PIGDDT group.Conclusion: The prevalence of osteopenia and osteoporosis may differ between clinical subtypes of PD and healthy controls. Osteopenia is more common than osteoporosis for all groups. The patients with PIGDDT of PD tended to have higher prevalence of osteoporosis, even at early stages of disease, compared to those with TDT and healthy controls.

Bone-Derived Factors as Potential Biomarkers for Parkinson's Disease

Background: Parkinson’s disease (PD) and osteoporosis are both common aging diseases. It is reported that PD has a close relationship with osteoporosis and bone secretory proteins may be involved in disease progression.

Objectives: To detect the bone-derived factors in plasma and cerebrospinal fluid (CSF) of patients with PD and evaluate their correlations with C-reaction protein (CRP) level, motor impairment, and Hoehn-Yahr (HY) stage of the disease.

Methods: We included 250 PD patients and 250 controls. Levels of osteocalcin (OCN), osteopontin (OPN), osteoprotegerin (OPG), Sclerostin (SO), Bone morphogenetic protein 2 (BMP2), and Dickkopf-1 (DKK-1) in plasma and CSF were measured by custom protein antibody arrays. Data were analyzed using Mann–Whitney U-test and Spearman’s receptor activator of NF-κB (RANK) correlation.

Results: Plasma levels of OCN and OPN were correlated with CRP levels and HY stage and motor impairment of PD. Furthermore, the plasma assessment with CSF detection may enhance their potential prediction on PD.

Conclusions: OCN and OPN may serve as potential biomarkers for PD. The inflammation response may be involved in the cross-talk between the two factors and PD.

Aging-related modifications to G protein-coupled receptor signaling diversity

Aging is a highly complex molecular process, affecting nearly all tissue systems in humans and is the highest risk factor in developing neurodegenerative disorders such as Alzheimer's and Parkinson's disease, cardiovascular disease and Type 2 diabetes mellitus. The intense complexity of the aging process creates an incentive to develop more specific drugs that attenuate or even reverse some of the features of premature aging. As our current pharmacopeia is dominated by therapeutics that target members of the G protein-coupled receptor (GPCR) superfamily it may be prudent to search for effective anti-aging therapeutics in this fertile domain. Since the first demonstration of GPCR-based β-arrestin signaling, it has become clear that an enhanced appreciation of GPCR signaling diversity may facilitate the creation of therapeutics with selective signaling activities. Such 'biased' ligand signaling profiles can be effectively investigated using both standard molecular biological techniques as well as high-dimensionality data analyses. Through a more nuanced appreciation of the quantitative nature across the multiple dimensions of signaling bias that drugs possess, researchers may be able to further refine the efficacy of GPCR modulators to impact the complex aberrations that constitute the aging process. Identifying novel effector profiles could expand the effective pharmacopeia and assist in the design of precision medicines. This review discusses potential non-G protein effectors, and specifically their potential therapeutic suitability in aging and age-related disorders.

Sheth M, Viswanath O, Urits I. Chronic Pain Treatment Strategies in Parkinson's Disease

Neurological disorders, including Parkinson's disease (PD), have increased in prevalence and are expected to further increase in the coming decades. In this regard, PD affects around 3% of the population by age 65 and up to 5% of people over the age of 85. PD is a widely described, physically and mentally disabling neurodegenerative disorder. One symptom often poorly recognized and under-treated by health care providers despite being reported as the most common non-motor symptom is the finding of chronic pain. Compared to the general population of similar age, PD patients suffer from a significantly higher level and prevalence of pain. The most common form of pain reported by Parkinson's patients is of musculoskeletal origin. One of the most used combination drugs for PD is Levodopa-Carbidopa, a dopamine precursor that is converted to dopamine by the action of a naturally occurring enzyme called DOPA decarboxylase. Pramipexole, a D2 dopamine agonist, and apomorphine, a dopamine agonist, and Rotigotine, a dopamine receptor agonist, have showed efficacy on PD-associated pain. Other treatments that have shown efficacy in treating pain of diverse etiologies are acetaminophen, Nonsteroidal anti-inflammatory drugs (NSAIDs), and cyclooxygenase-2 (COX-2) inhibitors. Opioids and opioid-like medications such as oxycodone, morphine, tramadol, and codeine are also commonly employed in treatment of chronic pain in PD. Other opioid related medications such as Tapentadol, a central-acting oral analgesic with combined opioid and noradrenergic properties, and Targinact, a combination of the opioid agonist oxycodone and the opioid antagonist naloxone have shown improvement in pain. Anticonvulsants such as gabapentin, pregabalin, lamotrigine, carbamazepine and tricyclic antidepressants (TCAs) can be trialed when attempting to manage chronic pain in PD. The selective serotonin and noradrenaline reuptake inhibitors (SNRIs) also possess pain relieving and antidepressant properties, but carry less of the risk of anticholinergic side effects seen in TCAs. Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has been shown in multiple studies to be effective against various types of PD associated pain symptoms. Massage therapy (MT) is one of the most common forms of complementary and alternative medicine. Studies have shown that pressure applied during MT may stimulate vagal activity, promoting reduced anxiety and pain, as well as increasing levels of serotonin. In a survey study of PD patients, rehabilitative therapy and physical therapy were rated as the most effective for pain reduction, though with only temporary relief but these studies were uncontrolled. Yoga has been studied for patients with a wide array of neurological disorders. In summary, PD pathology is thought to have a modulating effect on pain sensation, which could amplify pain. This could help explain a portion of the higher incidence of chronic pain felt by PD patients. A treatment plan can be devised that may include dopaminergic agents, acetaminophen, NSAIDs, opioids, antidepressants, physical therapies, DBS and other options discussed in this review. A thorough assessment of patient history and physical examination should be made in patients with PD so chronic pain may be managed effectively.

Current Perspectives on Aerobic Exercise in People with Parkinson's Disease

Parkinson's disease (PD) is a progressive neurological disorder characterized by motor and non-motor symptoms for which only symptomatic treatments exist. Exercise is a widely studied complementary treatment option. Aerobic exercise, defined as continuous movement of the body's large muscles in a rhythmic manner for a sustained period that increases caloric requirements and aims at maintaining or improving physical fitness, appears promising. We performed both a scoping review and a systematic review on the generic and disease-specific health benefits of aerobic exercise for people with PD. We support this by a meta-analysis on the effects on physical fitness (VO2max), motor symptoms (Movement Disorder Society Unified Parkinson's Disease Rating Scale (MDS-UPDRS) motor section), and health-related quality of life (39-item Parkinson's disease Questionnaire (PDQ-39)). Aerobic exercise has generic health benefits for people with PD, including a reduced incidence of cardiovascular disease, a lower mortality, and an improved bone health. Additionally, there is level 1 evidence that aerobic exercise improves physical fitness (VO2max) and attenuates motor symptoms (MDS-UPDRS motor section) in the off-medication state, although the long-term effects (beyond 6 months) remain unclear. Dosing the exercise matters: improvements appear to be greater after training at higher intensities compared with moderate intensities. We found insufficient evidence for a beneficial effect of aerobic exercise on health-related quality of life (PDQ-39) and conflicting results regarding non-motor symptoms. Compliance to exercise regimes is challenging for PD patients but may be improved by adding exergaming elements to the training program. Aerobic exercise seems a safe intervention for people with PD, although care must be taken to avoid falls in at-risk individuals. Further studies are needed to establish the long term of aerobic exercise, including a focus on non-motor symptoms and health-related quality of life.

Acute Spinal Cord Contusion in a Patient with Multiple Upper Cervical Fractures, Parkinson's Disease, and Torticollis: Surgical Management

Case Report. Spine surgery in patients with Parkinson's disease (PD) involves increased risk. We describe a case of cervical myelopathy in a patient with PD, multiple fractures involving the atlas and axis vertebrae, and spasmodic torticollis. The patient was successfully treated with an upper cervical decompression and occipital-cervical (OC) fusion surgery. Strategies for torticollis reduction and successful surgical outcome are discussed. Risks and benefits must be carefully weighed when considering occipital cervical fusion in PD patients. Conclusion. Intraoperative manual reduction of laterocollis is possible after general endotracheal anesthesia, and continuous neuromonitoring is established. Use of optimizing strategies such as perioperative botulinum injections and intraoperative O-arm navigation should be considered.

The relationships of vitamin D, vitamin D receptor gene polymorphisms, and vitamin D supplementation with Parkinson's disease

In recent years, many studies have investigated the correlations between Parkinson's disease (PD) and vitamin D status, but the conclusion remains elusive. The present review focuses on the associations between PD and serum vitamin D levels by reviewing studies on the associations of PD with serum vitamin D levels and vitamin D receptor (VDR) gene polymorphisms from PubMed, Web of Science, Cochrane Library, and Embase databases. We found that PD patients have lower vitamin D levels than healthy controls and that the vitamin D concentrations are negatively correlated with PD risk and severity. Furthermore, higher vitamin D concentrations are linked to better cognitive function and mood in PD patients. Findings on the relationship between VDR gene polymorphisms and the risk of PD are inconsistent, but the FokI (C/T) polymorphism is significantly linked with PD. The occurrence of FokI (C/T) gene polymorphism may influence the risk, severity, and cognitive ability of PD patients, while also possibly influencing the effect of Vitamin D3 supplementation in PD patients. In view of the neuroprotective effects of vitamin D and the close association between vitamin D and dopaminergic neurotransmission, interventional prospective studies on vitamin D supplementation in PD patients should be conducted in the future.

Management of Pain in Parkinson's Disease

Pain is a very frequent symptom with influence on the quality of life in Parkinson’s disease (PD), but is still underdiagnosed and commonly treated only unsystematically. Pain etiology and pain character are often complex and multi-causal, and data regarding treatment recommendations are limited. Pain can be primarily related to PD but frequently it is associated with secondary diseases, such as arthrosis of the spine or joints. However, even basically PD-unrelated pain often is amplified by motor- or non-motor PD symptoms, such as akinesia or depression. Beyond an optimization of anti-parkinsonian treatment, additional pain treatment strategies are usually needed to properly address pain in PD. A careful pain history and diagnostic work-up is essential to rate the underlying pain pathophysiology and to develop a targeted therapeutic concept. This review gives an overview on how pain is treated in PD patients and how patients assess the effectiveness of these therapies; here, the manuscript focuses on pathophysiology-driven suggestions for a multimodal pain management in clinical practice.

A genome-wide scan for pleiotropy between bone mineral density and nonbone phenotypes

Osteoporosis is the most common metabolic bone disorder globally and is characterized by skeletal fragility and microarchitectural deterioration. Genetic pleiotropy occurs when a single genetic element is associated with more than one phenotype. We aimed to identify pleiotropic loci associated with bone mineral density (BMD) and nonbone phenotypes in genome-wide association studies. In the discovery stage, the NHGRI-EBI Catalog was searched for genome-wide significant associations (P value < 5 × 10-8), excluding bone-related phenotypes. SNiPA was used to identify proxies of the significantly associated single nucleotide polymorphisms (SNPs) (r 2 = 1). We then assessed putative genetic associations of this set of SNPs with femoral neck (FN) and lumbar spine (LS) BMD data from the GEFOS Consortium. Pleiotropic variants were claimed at a false discovery rate < 1.4 × 10-3 for FN-BMD and < 1.5 × 10-3 for LS-BMD. Replication of these genetic markers was performed among more than 400 000 UK Biobank participants of European ancestry with available genetic and heel bone ultrasound data. In the discovery stage, 72 BMD-related pleiotropic SNPs were identified, and 12 SNPs located in 11 loci on 8 chromosomes were replicated in the UK Biobank. These SNPs were associated, in addition to BMD, with 14 different phenotypes. Most pleiotropic associations were exhibited by rs479844 (AP5B1, OVOL1 genes), which was associated with dermatological and allergic diseases, and rs4072037 (MUC1 gene), which was associated with magnesium levels and gastroenterological cancer. In conclusion, 12 BMD-related genome-wide significant SNPs showed pleiotropy with nonbone phenotypes. Pleiotropic associations can deepen the genetic understanding of bone-related diseases by identifying shared biological mechanisms with other diseases or traits.

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.

Falls in Synucleinopathies

Parkinson's disease (PD) and other synucleinopathies, namely dementia with Lewy bodies (DLB) and multiple system atrophy (MSA), are common degenerative neurological disorders that share synuclein pathology. Although certain cardinal features of parkinsonism, including bradykinesia and rigidity, respond well to levodopa, axial features, such as gait and balance impairment, are less reliably responsive to dopaminergic therapy and surgical interventions. Consequently, falls are common in PD and other synucleinopathies and are a major contributor toward injury and loss of independence. This underscores the need for appropriate fall risk assessment and implementation of preventative measures in all patients with parkinsonism. The aim of this review is therefore to explore modifiable and non-modifiable risk factors for falls in synucleinopathies. We next review and evaluate the evidence for pharmacological, nonpharmacological, and surgical approaches for fall prevention, and emphasize individualized and multifaceted approaches.

Bile acid abnormality induced by intestinal dysbiosis might explain lipid metabolism in Parkinson's disease

Intestinal dysbiosis refers to an imbalance in the intestinal flora. The concept of small intestinal bacterial overgrowth (SIBO), a condition of abnormal proliferation of the small intestine microbiota, has been proposed as a form of small intestine dysbiosis. In Parkinson's disease patients, weight loss and metabolic disorders such as lipid abnormalities are frequently encountered. This was a prospective investigation of the presence of SIBO using the lactulose breath test, Parkinson's disease symptoms, medications, abdominal symptoms, and blood data involving 39 Parkinson's disease patients. Of the 39 patients, 19 were positive for SIBO, 16 were negative, and 4 were equivocal. SIBO-positive patients had a significantly smaller dopaminergic drug load (dopamine replacement of Parkinson's disease drug potency) (P = 0.009) and significantly lower serum triglyceride (TG) (P = 0.024) and total bilirubin (P = 0.019) levels. No relationship was seen between the presence or absence of SIBO and motor or abdominal symptoms. The following hypothesis was developed with regard to the possibility that intestinal bacterial overgrowth has various effects that are exhibited via bile acid metabolism in Parkinson's disease patients. Serum bilirubin levels become higher as bilirubin metabolism declines with decreases in the intestinal bacteria. At the same time, bile acid is broken down due to increased intestinal bacteria, and lipid absorption decreases. This induces low serum TG levels and leads to weight loss. By a similar mechanism, there is less absorption of vitamin D as bile acid levels decrease, leading to osteoporosis and fractures. The possibility that some of the non-motor manifestations accompanying Parkinson's disease are caused by intestinal dysbiosis needs to be considered.

Chlorpyrifos Exposure Induces Parkinsonian Symptoms and Associated Bone Loss in Adult Swiss Albino Mice

Prenatal and early life exposure of chlorpyrifos (CPF), a widely used pesticide, is known to cause neuronal deficits and Parkinson's disease (PD). However, data about the effect of its exposure at adult stages on PD-like symptoms and associated bone loss is scanty. In the present study, we investigated the impact of CPF on the behavioral alterations seen in PD using adult Swiss albino mice. PD is often associated with bone loss. Hence, skeletal changes were also evaluated using micro-computed tomography and histology. MPTP was used as a positive control. Cell culture studies using MC3T3E-1, SHSY5Y, and primary osteoclast cultures were done to understand the cellular mechanism for the behavioral and skeletal changes. Our results showed that CPF treatment leads to PD-like symptoms due to the loss of dopaminergic neurons. Moreover, CPF has a deleterious effect on the trabecular bone through both indirect changes in circulating factors and direct stimulation of multinucleate osteoclast cell formation. The impact on the bone mass was even stronger than MPTP. In conclusion, this is the first report demonstrating that CPF induces parkinsonian features in adult Swiss albino mice and it is accompanied by loss of trabecular bone.

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.

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.