Promoting sympathovagal balance in multiple sclerosis; pharmacological, non-pharmacological, and surgical strategies

The cost-utility analysis of adding ocrelizumab to the treatment plan for primary progressive multiple sclerosis in Iran

BACKGROUND

This study evaluates the cost-effectiveness of adding ocrelizumab to supportive care for primary progressive multiple sclerosis (PPMS) in Iran.

RESEARCH DESIGN AND METHODS

Using a lifetime horizon from the payer's perspective, we developed a decision analytic model with Expanded Disability Status Scales (EDSS) as Markov health states while taking transition probabilities and treatment effects into account. Data were sourced from clinical trials and other literature. The target population was PPMS patients receiving either supportive care or ocrelizumab. We assessed cost- effectiveness through total costs, quality-adjusted life-years (QALYs), and the incremental cost- effectiveness ratio (ICER). Sensitivity analyses addressed uncertainties.

RESULTS

The addition of ocrelizumab to supportive care provided an incremental gain of 0.89 QALYs and an additional cost of US$76,771.34, resulting in an ICER of US$86,220.35 compared to supportive care, which is 5.2 times Iran's GDP per capita (US$16,557). Thus, ocrelizumab is not cost-effective at the threshold of one time GDP per capita. However, the probability of cost-effectiveness increases at higher thresholds. Sensitivity analyses confirmed the robustness of the results.

CONCLUSION

While ocrelizumab is not cost-effective at the threshold of one-time GDP per capita, its clinical benefits are significant. Formulating healthcare policies for high-cost medications with low alternatives like ocrelizumab is essential.

Autonomic nervous system disorders in multiple sclerosis

Multiple sclerosis (MS) is a chronic progressive demyelinating disease of the central nervous system (CNS), which also affects the autonomic nervous system (ANS). Manifestations of MS in the ANS include urological, sexual, gastrointestinal, cardiovascular, and thermoregulatory disorders as well as increased fatigue. These problems are common yet are often underestimated due to the non-specificity of the symptoms and the limited evaluation of the ANS in the usual clinical practice. Most of these symptoms seem to be related to localized lesions in the CNS. However, the mechanisms by which these disorders are caused in MS have not been fully investigated, thus preventing any focused etiological treatment. The most common disorders of the ANS in MS represent a challenge for clinicians due to the variability of the clinical picture and our minimal data on their diagnosis and treatment. Early diagnosis and initiation of individualized treatment regimens, often in need of multiple approaches, seem to yield the best results in managing ANS dysfunction in MS patients.

Can biofeedback-based training alleviate fatigue and vigilance performance in fatigued MS patients?

MS related fatigue might be related to autonomous nervous system (ANS) dysfunctions or to inflammation related vagal (hyper-) activation. Consequently, influencing ANS status may lead to relieve of fatigue. We used two opposite biofeedback interventions to either increase sympathetic ("self-alert training", SAT) or parasympathetic activation ("progressive muscle relaxation", PMR). We recorded fatigue status of patients before and after a challenging vigilance task, their behavioural performance on this task, their skin conductance response (SCR), and parameters indicating parasympathetic activity concerning heart rate variability (HRV). We repeated these recordings after the biofeedback training sessions. Patients of the SAT group were able to learn to increase their SCR voluntarily. Patients of the PMR group showed increasing parameters indicating parasympathetic modulation of the HRV. The vigilance task increased their feeling of fatigue. However, there was no effect of biofeedback training on either fatigue status or performance on the vigilance task. Our results show that MS patients can learn to change voluntarily their ANS activity using biofeedback instructions based on SCR and this can be used in future studies to test the postulated link between ANS and fatigue. However, in this experimental intervention we were unable to document a relation between ANS activity and fatigue.Trial registration: ClinicalTrials.gov identifier: NCT03268187.

PACAP/PAC1 Regulation of Inflammation via Catecholaminergic Neurons in a Model of Multiple Sclerosis

The sympathetic nervous system (SNS) serves to maintain homeostasis of vital organ systems throughout the body, and its dysfunction plays a major role in human disease. The SNS also links the central nervous system to the immune system during different types of stress via innervation of the lymph nodes, spleen, thymus, and bone marrow. Previous studies have shown that pituitary adenylate cyclase-activating polypeptide (PACAP, gene name adcyap1) exhibits anti-inflammatory properties in the experimental autoimmune encephalomyelitis (EAE) model of multiple sclerosis. Because PACAP is known to regulate SNS function, we hypothesized that part of the immunoprotective action of PACAP is due to its neuromodulatory effects on sympathetic neurons. To examine this, we used an inducible, targeted approach to conditionally disrupt not only the PACAP-preferring PAC1 receptor gene (adcyap1r1) in dopamine β-hydroxylase-expressing cells, which includes postganglionic sympathetic neurons, but also catecholaminergic neurons in the brain and adrenomedullary chromaffin cells. In contrast to our previous EAE studies using PACAP global knockout mice which developed severe and prolonged EAE, we found that mice with conditional loss of PAC1 receptors in catecholaminergic cells developed a delayed time course of EAE with reduced helper T cell type 1 (Th1) and Th17 and enhanced Th2 cell polarization. At later time points, similar to mice with global PACAP loss, mice with conditional loss of PAC1 exhibited more severe clinical disease than controls. The latter was associated with a reduction in the abundance of thymic regulatory T cells (Tregs). These studies indicate that PAC1 receptor signaling acts in catecholaminergic cells in a time-dependent manner. At early stages of disease development, it enhances the ability of the SNS to polarize the Th response towards a more inflammatory state. Then, after disease is established, it enhances the ability of the SNS to dampen the inflammatory response via T_regs. The lack of concordance in results between global PACAP KO mice and mice with the PAC1 deletion targeted to catecholaminergic cells during early EAE may be explained by the fact that PACAP acts to regulate inflammation via multiple receptor subtypes and multiple targets, including inflammatory cells.

Spasticity in multiple sclerosis: Contribution of inflammation, autoimmune mediated neuronal damage and therapeutic interventions

In contrast to other diseases that go along with spasticity (e.g. spinal cord injury), spasticity in chronic autoimmune diseases involving the CNS is complicated by the ongoing damage of neuronal networks that leads to permanent changes in the clinical picture of spasticity. Multiple sclerosis (MS) is the most frequent autoimmune disease of the central nervous system (CNS) and spasticity is one of the most disabling symptoms. It occurs in more than 80% MS patients at some point of the disease and is associated with impaired ambulation, pain and the development of contractures. Besides causing cumulative structural damage, neuroinflammation occurring in MS leads to dynamic changes in motor circuit function and muscle tone that are caused by cytokines, prostaglandins, reactive oxygen species and stress hormones that affect neuronal circuits and thereby spasticity. The situation is complicated further by the fact that therapeutics used for the immunotherapy of MS may worsen spasticity and drugs used for the symptomatic treatment of spasticity have been shown to have the potential to alter immune cell function and CNS autoimmunity itself. This review summarizes the current knowledge on the immunologic pathways that are involved in the development, maintenance, dynamic changes and pharmacological modulation of spasticity in MS.

A structural MRI study of cholinergic pathways and cognition in multiple sclerosis

Background

White matter hyperintensities (WMH) in the cholinergic pathways are associated with cognitive performance in Alzheimer's disease. This study aimed to evaluate the relationship between the volume reduction of cholinergic pathways and cognitive function in patients with multiple sclerosis (MS).

Methods

Thirty-two MS patients underwent a brain MRI and cognitive measurements including the Mini-Mental State Examination (MMSE) and the Japanese version of the Montreal Cognitive Assessment (MoCA-J). The extent of WMH within the cholinergic pathways was assessed using the Cholinergic Pathways Hyperintensities Scale (CHIPS). Computerized WMH volumes were also obtained. FreeSurfer was used to measure regional volumes including the cortical and subcortical volumes. The correlations among the CHIPS, the WMH volume, and the clinical data were assessed, in addition to the correlations between the cognitive scores and regional volumes measured by FreeSurfer.

Results

The CHIPS score and the WMH volume were strongly positively correlated with each other (r = 0.87, P < 0.001). The CHIPS score had significantly negative correlations with the MMSE (r = - 0.49, P = 0.003) and the MoCA-J (r = - 0.47, P = 0.005) results. The WMH volume had significantly negative correlations with the MMSE (r = - 0.54, P = 0.001) and the MoCA-J (r = - 0.57, P < 0.001) results. In the analysis by FreeSurfer, both the MMSE and MoCA-J scores had significant positive correlations only with the volume of the corpus callosum.

Conclusions

The CHIPS score tended to be less sensitive to the WMH volume in cognitive function evaluation, although the difference did not reach the level of statistical significance. Thus the CHIPS method may not be as effective in MS patients.

[Autonomic dysfunction in patients with multiple sclerosis]

AIM

To optimize the early diagnosis of the autonomic dysfunction in patients with MS.

MATERIAL AND METHODS

The main group consisted of 46 patients: 15 men and 31 women with MS (McDonald, 2005), the average age was 33.35±9.9 years, the average score of the Expanded disability scale (EDSS) was 2.8±1.17 points. The control group consisted of 24 healthy subjects matched by age and sex with the main group. A study of the autonomic nervous system was carried out using the Scheme for detection of signs of autonomic disorders (A.M. Vein, 1998) and analysis of heart rate variability (HRV) at rest and after active orthostatic test (AOT).

RESULTS

Autonomic dysfunction was found in 73% of the patients. The overall score of the Scheme was significantly higher in MS patients (31.32±9.43 points) compared to the comparison group (2.36±4.39 points, p<0.05). According to HRV, the contribution of brainstem autonomic centers in the regulation of stress-response during AOP was significantly reduced (p<0.05) and was characterized by the lack of activation of the sympathetic division of the ANS. In patients with MS, cerebral influences were dominating on HRV baseline records, evaluated by the domination of the VLF component in the spectrum. During AOP, VLF was almost leveled in both groups, and the VLF changes in patients before and after the AOP reached statistical significance (p<0.05).

CONCLUSION

The use of the Scheme is preferable in outpatient clinics to screen the large numbers of patients with MS, and then selected patients could be referred to the instrumental methods of investigation.

Clinical Applicability of Assessment of Jugular Flow over the Individual Cardiac Cycle Compared with Current Ultrasound Methodology

There is growing interest in measuring cerebral venous outflow with ultrasound (US). However, results obtained with the current US Doppler methodology, which uses just a single value of cross-sectional area (CSA) of the vessel, are highly variable and inconclusive. The product of CSA and time-averaged velocity in the case of pulsatile vessels may be a possible source of error, particularly for a pulsatile vein like the internal jugular vein (IJV), where the cardiac pump transmits a sequence of well-established waves along the conduit. We herein propose a novel technique for US IJV flow assessment that accurately accounts for IJV CSA variations during the cardiac cycle. Five subjects were investigated with a high-resolution real-time B-mode video, synchronized with an electrocardiography trace. In this approach, CSA variations representing the pulsatility of the IJV are overlapped with the velocity curve obtained by the usual spectral Doppler trace. The overlap is then phased point by point using the electrocardiography pacemaker. This allows us to experimentally measure the velocity variation in relation to the change in CSA precisely, ultimately enabling calculation of IJV flow. (i) The sequence of CSA variation with respect to the electrocardiography waves corresponds exactly to the jugular venous pulse as measured in physiology. (ii) The methodology permits us to phase the velocity and CSA, which is ultimately what is currently lacking to precisely calculate the flow in the IJV with US. (iii) The time-averaged flow, calculated with the described technique, is very close to that calculated assuming a constant IJV CSA, whereas the time-dependent flow shows differs as much as 40%. (iv) Finally, we tested the accuracy of the technique with a methodology that may allow for universal assessment of the accuracy of each personal US-based evaluation of flow rate.

Why Current Doppler Ultrasound Methodology Is Inaccurate in Assessing Cerebral Venous Return: The Alternative of the Ultrasonic Jugular Venous Pulse

Assessment of cerebral venous return is growing interest for potential application in clinical practice. Doppler ultrasound (DUS) was used as a screening tool. However, three meta-analyses of qualitative DUS protocol demonstrate a big heterogeneity among studies. In an attempt to improve accuracy, several authors alternatively measured the flow rate, based on the product of the time average velocity with the cross-sectional area (CSA). However, also the quantification protocols lacked of the necessary accuracy. The reasons are as follows: (a) automatic measurement of the CSA assimilates the jugular to a circle, while it is elliptical; (b) the use of just a single CSA value in a pulsatile vessel is inaccurate; (c) time average velocity assessment can be applied only in laminar flow. Finally, the tutorial describes alternative ultrasound calculation of flow based on the Womersley method, which takes into account the variation of the jugular CSA overtime. In the near future, it will be possible to synchronize the electrocardiogram with the brain inflow (carotid distension wave) and with the outflow (jugular venous pulse) in order to nicely have a noninvasive ultrasound picture of the brain-heart axis. US jugular venous pulse may have potential use in neurovascular, neurocognitive, neurosensorial, and neurodegenerative disorders.

Genetic, Epigenetic, and Environmental Factors Influencing Neurovisceral Integration of Cardiovascular Modulation: Focus on Multiple Sclerosis

Thought to be an autoimmune inflammatory CNS disease, multiple sclerosis (MS) involves multiple pathologies with heterogeneous clinical presentations. An impaired neurovisceral integration of cardiovascular modulation, indicated by sympathetic and parasympathetic autonomic nervous system (ANS) dysfunction, is among common MS clinical presentations. ANS dysfunction could not only enhance MS inflammatory and neurodegenerative processes, but can also lead to clinical symptoms such as depression, fatigue, sleep disorder, migraine, osteoporosis, and cerebral hemodynamic impairments. Therefore, factors influencing ANS functional activities, in one way or another, will have a significant impact on MS disease course. This review describes the genetic and epigenetic factors, and their interactions with a number of environmental factors contributing to the neurovisceral integration of cardiovascular modulation, with a focus on MS. Future studies should investigate the improvement in cardiovascular ANS function, as a strategy for preventing and minimizing MS-related morbidities, and improving patients' quality of life.

Autonomic Dysregulation in Multiple Sclerosis

Multiple sclerosis (MS) is a chronic, progressive central neurological disease characterized by inflammation and demyelination. In patients with MS, dysregulation of the autonomic nervous system may present with various clinical symptoms including sweating abnormalities, urinary dysfunction, orthostatic dysregulation, gastrointestinal symptoms, and sexual dysfunction. These autonomic disturbances reduce the quality of life of affected patients and constitute a clinical challenge to the physician due to variability of clinical presentation and inconsistent data on diagnosis and treatment. Early diagnosis and initiation of individualized interdisciplinary and multimodal strategies is beneficial in the management of autonomic dysfunction in MS. This review summarizes the current literature on the most prevalent aspects of autonomic dysfunction in MS and provides reference to underlying pathophysiological mechanisms as well as means of diagnosis and treatment.