Prognostic value of neurofilament light in blood in patients with polyneuropathy: A systematic review.

Neurofilament light protein (NfL) is a part of the neuronal skeleton, primarily expressed in axons, and is released when nerves are damaged. NfL has been found to be a potential diagnostic biomarker in different types of polyneuropathies. However, whether NfL levels can be used as a predictor for the risk of disease progression is currently less understood. We searched MEDLINE (PubMed), Embase, Cochrane Library, and Web of Science Searches and included longitudinal studies with a baseline and follow-up examination of adult patients with polyneuropathy and NfL measured in blood. Twenty studies investigating NfL as a predictor of disease progression were identified, examining eight polyneuropathy subtypes. The results from studies in Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) patients were divergent, with two out of five studies finding a significant association between NfL levels and clinical outcomes. Meta-analysis of the three Guillian-Barré Syndrome (GBS) studies found higher odds for the inability to run after 1 year in patients with high levels of NfL (odds ratio 2.18, 95% confidence interval 1.04-4.56). Results from studies examining other subacute or chronic polyneuropathies like Charcot-Marie-Tooth (CMT) varied in study design and results. Our findings suggest NfL can be used as a predictor of disease progression, particularly in polyneuropathies such as CIDP and GBS. However, NfL may not serve as a reliable and cost-effective biomarker for slowly progressive polyneuropathies like CMT. Future standardized studies considering NfL as a prognostic blood biomarker in patients with different types of polyneuropathies are warranted.

Humoral immune response to COVID-19 vaccine in patients with myasthenia gravis.

We investigated the humoral response to the Pfizer-BioNTech COVID-19 (BNT162b2) vaccine in patients with myasthenia gravis on or off immunosuppressants and compared this to the response in healthy individuals. The SARS-CoV-2 IgG response and neutralizing capacity were measured in 83 patients (57 on immunosuppressants) and 332 healthy controls at baseline, three weeks, and two and six months after the vaccine. We found that the proportion of positive humoral response was lower in patients on immunosuppressants vs. controls at three weeks and two months (p ≤ 0.001), but not at six months post-vaccination (p = 0.379).

Hypokalemic periodic paralysis: a 3-year follow-up study.

BACKGROUND AND OBJECTIVES: Primary hypokalemic periodic paralysis (HypoPP) is an inherited channelopathy most commonly caused by mutations in CACNA1S. HypoPP can present with different phenotypes: periodic paralysis (PP), permanent muscle weakness (PW), and mixed weakness (MW) with both periodic and permanent weakness. Little is known about the natural history of HypoPP. METHODS: In this 3-year follow-up study, we used the MRC scale for manual muscle strength testing and whole-body muscle MRI (Mercuri score) to assess disease progression in individuals with HypoPP-causing mutations in CACNA1S. RESULTS: We included 25 men (mean age 43 years, range 18-76 years) and 12 women (mean age 42 years, range 18-76 years). Two participants were asymptomatic, 21 had PP, 12 MW, and two PW. The median number of months between baseline and follow-up was 42 (range 26-52). Muscle strength declined in 11 patients during follow-up. Four of the patients with a decline in muscle strength had no attacks of paralysis during follow-up, and two of these patients had never had attacks of paralysis. Fat replacement of muscles increased in 27 patients during follow-up. Eight of the patients with increased fat replacement had no attacks of paralysis during follow-up, and two of these patients had never had attacks of paralysis. DISCUSSION: The study demonstrates that HypoPP can be a progressive myopathy in both patients with and without attacks of paralysis.

A Scoping Review Investigating the "Gene-Dosage Theory" of Mitochondrial DNA in the Healthy Skeletal Muscle.

This review provides an overview of the evidence regarding mtDNA and valid biomarkers for assessing mitochondrial adaptions. Mitochondria are small organelles that exist in almost all cells throughout the human body. As the only organelle, mitochondria contain their own DNA, mitochondrial DNA (mtDNA). mtDNA-encoded polypeptides are subunits of the enzyme complexes in the electron transport chain (ETC) that are responsible for production of ATP to the cells. mtDNA is frequently used as a biomarker for mitochondrial content, since changes in mitochondrial volume are thought to induce similar changes in mtDNA. However, some exercise studies have challenged this "gene-dosage theory", and have indicated that changes in mitochondrial content can adapt without changes in mtDNA. Thus, the aim of this scoping review was to summarize the studies that used mtDNA as a biomarker for mitochondrial adaptions and address the question as to whether changes in mitochondrial content, induce changes in mtDNA in response to aerobic exercise in the healthy skeletal muscle. The literature was searched in PubMed and Embase. Eligibility criteria included: interventional study design, aerobic exercise, mtDNA measurements reported pre- and postintervention for the healthy skeletal muscle and English language. Overall, 1585 studies were identified. Nine studies were included for analysis. Eight out of the nine studies showed proof of increased oxidative capacity, six found improvements in mitochondrial volume, content and/or improved mitochondrial enzyme activity and seven studies did not find evidence of change in mtDNA copy number. In conclusion, the findings imply that mitochondrial adaptions, as a response to aerobic exercise, can occur without a change in mtDNA copy number.

Misinterpretation of non-systemic vasculitic neuropathy results in delayed treatment.

This case report presents two patients who were diagnosed with non-systemic vasculitic neuropathy (NSVN). The phenotypes were atypical: 1) slowly progressive neuropathy and 2) plexopathy in contrast to the classic NSVN phenotype: painful, asymmetric with subacute progression. Both patients had remarkable responses to the immunosuppressants prednisolone and rituximab, and the cases highlight the importance to consider NSVN as a differential diagnosis of patients with neuropathy of unknown aetiology, as treatment can be initiated to avoid irreversible nerve damage.

Effect of strength training on functional outcomes and strength in patients with polyneuropathy: A scoping review.

Introduction: Polyneuropathy (PNP) is a chronic progressive disease that over time can lead to damage of sensory, motor and/or autonomic peripheral nerves. Symptoms vary from predominantly sensory to severe sensorimotor affection both proximally and distally. This can result in considerable functional impairments that affect activities of daily living. In other neurological patients, strength training has shown to improve strength and functional outcomes. Since medical treatment only exists for very few percentages of the underlying causes it is obvious to consider if strength training could be a potential treatment for functional impairments. To date little is known on the effect of strength training in patients with PNP. Aim: The aim of this scoping review was to summarize research on strength training and outcomes on physical function in patients with PNP. Methods: We systematically searched five data bases; Pubmed, Embase, Cinahl, Cochrane library and Web of science. Studies on strength training (load ≥70% of 1RM) in patients with PNP were included. The search was carried out in November 2022. Results: 362 articles were screened by title and abstract, 101 articles were full text screened. Eight studies were included. Patients with Charcot-Marie-Tooth (CMT), chronic inflammatory polyneuropathy (CIDP) and diabetic polyneuropathy (DPN) were represented in the studies (five RCTs, two case-series, and one cross-over trial). The methodological quality ranged from fair-poor in seven studies, one study reached good quality. Results from the studies indicated that strength training in CMT, CIDP and DPN may improve strength. However, various outcomes were used to evaluate strength training, so direct comparisons were difficult. Discussion: In this scoping review we summarized research on strength training and outcomes evaluated in interventions in patients with PNP. Eight studies were included, they indicated that strength training may be beneficial for patients with PNP. However, due to low methodological strength of most studies a recommendation for patients with PNP cannot be made. Thus, the low number of studies with relatively low quality, where various functional outcomes were used, underscores the importance of future studies to evaluate the effect of strength training on relevant functional outcomes and strength in patients with PNP.

Validation of Two Activity Monitors in Slow and Fast Walking Hospitalized Patients.

To evaluate interventions to promote physical activity, valid outcome measures are important. This study evaluated the validity and reliability of the ActivPAL3™ and the SENS motion® activity monitors with regard to the number of steps taken, walking, and sedentary behavior in hospitalized patients (n = 36) (older medical patients (+65 years) (n = 12), older patients (+65) with acute hip fracture (n = 12), and patients (+18) who underwent acute high-risk abdominal surgery (n = 12)). Both monitors showed good (≥60%) percentage agreement with direct observation for standing and no. of steps (all gait speeds) and high agreement (≥80%) for lying. For walking, ActivPAL3™ showed moderate percentage agreement, whereas SENS motion® reached high percentage agreement. The relative reliability was moderate for sedentary behavior for both monitors. The ActivPAL3™ showed poor (walking) to moderate (steps) reliability for walking and steps, whereas SENS motion® showed moderate reliability for both activities. For slow walkers, the relative reliability was moderate for SENS motion® and poor for ActivPAL3™. This trial is registered with the ClinicalTrials.gov identifier NCT04120740.

Feasibility and implementation fidelity of a co-designed intervention to promote in-hospital mobility among older medical patients-the WALK-Copenhagen project (WALK-Cph).

BACKGROUND: Mobility interventions can prevent functional decline among older patients, but implementation of such interventions may be complicated by barriers in the clinical setting. The WALK-Copenhagen project (WALK-Cph) is aimed at promoting a 24-h mobility among older medical patients during hospitalization. The WALK-Cph intervention was co-designed by researchers and stakeholders to tailor the intervention to the clinical context. The aim of this study was to investigate the feasibility and implementation fidelity of the WALK-Cph intervention before evaluating clinical effectiveness in a randomized controlled trial (ClinicalTrials.gov NCT03825497). METHODS: The WALK-Cph intervention consisted of six components: a welcome folder explaining the importance of in-hospital activity, a WALK-plan prescribing up to three daily walking sessions during and after hospitalization, a WALK-path in the hallway that patients were motivated to use daily, exercise posters in the hallways and bedrooms, self-service on beverages and clothes, and discharge with a WALK-plan. The present study reports on phase 2 of WALK-Cph and consists of a feasibility and a fidelity component. The study was conducted at the two WALK-Cph intervention departments after the initiation of the WALK-Cph intervention. A cohort of older medical patients (+65) was recruited for the feasibility study to assess recruitment and data collection procedures and the method for assessment of activity. Simultaneously, implementation fidelity was assessed by observing clinical practice and intervention delivery at the intervention departments. RESULTS: A feasibility cohort of 48 patients was included. Inclusion was considered feasible with recruitment rates between 62% and 70% of all eligible patients. Also, data collection was conducted without obstacles, and all patients accepted to wear activity monitors. The fidelity observations showed that three of the six intervention components were partially implemented as planned whereas three components were not implemented as planned. CONCLUSION: The WALK-Cph intervention was found feasible, and although the intervention was not implemented with fidelity, the level of fidelity was considered sufficient to continue with further testing of the WALK-Cph intervention in a large-scale trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT03825497 (retrospectively registered). Protocol PubMed ID (PMID): 29523569.

Adaptations and modifications to a co-designed intervention and its clinical implementation: a qualitative study in Denmark.

BACKGROUND: There is a long-standing debate in implementation research on whether adaptations to evidence-based interventions (EBIs) are desirable in health care. If an intervention is adapted and not delivered as conceived and planned, it is said to have low fidelity. The WALK-Cph project was developed based on the assumption that involving stakeholders in co-design processes would facilitate the fidelity of an intervention to increase the mobility of acutely admitted older medical patients and its implementation in two hospitals in Denmark. The purpose of this study is to describe and analyse adaptations and modifications that were made to the co-designed WALK-Cph intervention and its implementation. METHODS: This study used a qualitative design. An ethnographic field study was performed using participant observations, workshops and semi-structured interviews. Data were analysed twice using the Framework Method. The first analysis was based on the frameworks from Stirman, Moore and Proctor. The second analysis, a retrospective modifications analysis, was based on the Adaptation-Impact Framework. RESULTS: Many different types of adaptations and modifications were made to the WALK-Cph intervention and its implementation plan. Most of the modifications were made on the contents of the intervention. In total, 44 adaptations and modifications were made, of which 21 were planned (adaptations) and 23 were made haphazardly (modifications). Most of the content and context adaptations and modifications made on the intervention had a mixed result regarding enhanced fidelity. The retrospective modifications analysis showed that modifications were ongoing and both situationally and contextually shaped. CONCLUSIONS: Although an extensive co-design process was carried out to facilitate the fidelity of the WALK-Cph intervention, this study showed that many adaptations and modifications were still made to both the intervention and its implementation plan. It could indicate that the co-design process had a small effect or that adaptations and modifications are ongoing and both situationally and contextually shaped, which challenge the assumption and the desire to be able to plan and control changes.