Easy to interpret coordinate based meta-analysis of neuroimaging studies: Analysis of brain coordinates (ABC).

BACKGROUND: Functional MRI and voxel-based morphometry are important in neuroscience. They are technically challenging with no globally optimal analysis method, and the multiple approaches have been shown to produce different results. It is useful to be able to meta-analyse results from such studies that tested a similar hypothesis potentially using different analysis methods. The aim is to identify replicable results and infer hypothesis specific effects. Coordinate based meta-analysis (CBMA) offers this, but the multiple algorithms can produce different results, making interpretation conditional on the algorithm. NEW METHOD: Here a new model based CBMA algorithm, Analysis of Brain Coordinates (ABC), is presented. ABC aims to be simple to understand by avoiding empirical elements where possible and by using a simple to interpret statistical threshold, which relates to the primary aim of detecting replicable effects. RESULTS: ABC is compared to both the most used and the most recently developed CBMA algorithms, by reproducing a published meta-analysis of localised grey matter changes in schizophrenia. There are some differences in results and the type of data that can be analysed, which are related to the algorithm specifics. COMPARISON TO OTHER METHODS: Compared to other algorithms ABC eliminates empirical elements where possible and uses a simple to interpret statistical threshold. CONCLUSIONS: There may be no optimal way to meta-analyse neuroimaging studies using CBMA. However, by eliminating some empirical elements and relating the statistical threshold directly to the aim of finding replicable effects, ABC makes the impact of the algorithm on any conclusion easier to understand.

Beta interferons as immunotherapy in multiple sclerosis: a new outlook on a classic drug during the COVID-19 pandemic.

Beta interferons (IFN-ß) are pleiotropic cytokines with antiviral properties. They play important roles in the pathogenesis of multiple sclerosis (MS), an incurable immune-mediated disorder of the central nervous system. The clinical expression of MS is heterogeneous, with relapses of neuroinflammation and with disability accrual in considerable part unrelated to the attacks. The injectable recombinant IFN-ß preparations are the first approved disease-modifying treatments for MS. They have moderate efficacy in reducing the frequency of relapses, but good long-term cost-efficacy and safety profiles, so are still widely used. They have some tolerability and adherence issues, partly mitigated in recent years by the introduction of a PEGylated formulation and use of 'smart' autoinjector devices. Their general impact on long-term disability is modest but could be further improved by developing accurate tools for identifying the patient profile of best responders to IFN-ß. Here, we present the IFN-ß-based immunomodulatory therapeutic approaches in MS, highlighting their place in the current coronavirus disease (COVID-19) pandemic. The potential role of IFN-ß in the treatment of COVID-19 is also briefly discussed.

Comorbidity in multiple sclerosis: its temporal relationships with disease onset and dose effect on mortality.

BACKGROUND AND PURPOSE: We aimed to determine the burden of comorbidities at the time of diagnosis of multiple sclerosis (MS), the risk of developing new comorbidities after diagnosis and the effect of comorbidities on mortality in patients with MS. METHODS: This study used data from 2526 patients with incident MS and 9980 age-, sex- and physician-matched controls without MS identified from the UK Clinical Practice Research Datalink. RESULTS: Before the MS diagnosis, the adjusted odds ratio for the association between MS and a Charlson comorbidity index score of 1-2, 3-4 or ≥5 was 131 [95% confidence interval (CI), 1.17-1.47], 1.65 (95% CI, 1.20-2.26) or 3.26 (95% CI, 1.58-6.70), respectively. MS was associated with increased risks of cardiovascular and neurological/mental diseases. After diagnosis, the adjusted hazard ratio for the association between MS and an increased risk of developing comorbidities was 1.13 (95% CI, 1.00-1.29). The risk of developing any comorbidity in terms of neoplasms, musculoskeletal/connective tissue diseases or neurological/mental diseases was higher in MS. Patients with MS had a higher mortality risk compared with controls, with a hazard ratio of 2.29 (95% CI, 1.81-2.73) after adjusting for comorbidities. There was a dose effect of pre-existing comorbidities on mortality. CONCLUSIONS: Patients with MS have an increased risk of developing multiple comorbidities both before and after diagnosis and pre-existing comorbidities have an impact on survival.

Coordinate based meta-analysis of networks in neuroimaging studies.

Meta-analysis of summary results from published neuroimaging studies independently testing a common hypothesis is performed using coordinate based meta-analysis (CBMA), which tests for consistent activation (in the case of functional MRI studies) of the same anatomical regions. Using just the reported coordinates it is also possible to meta-analyse coactivated regions to reveal a network-like structure of coordinate clusters (network nodes) distributed at the coactivated locations and a measure of the coactivation strength (network edges), which is determined by the presence/absence of reported activation. Here a new coordinate-based method to estimate a network of coactivations is detailed, which utilises the Z score accompanying each reported. Coordinate based meta-analysis of networks (CBMAN) assumes that if the activation pattern reported by independent studies is truly consistent, then the relative magnitude of these Z scores might also be consistent. It is hypothesised that this is detectable as Z score covariance between coactivated regions provided the within study variances are small. Advantages of using the Z scores instead of coordinates to measure coactivation strength are that censoring by the significance thresholds can be considered, and that using a continuous measure rather than a dichotomous one can increase statistical power. CBMAN uses maximum likelihood estimation to fit multivariate normal distributions to the standardised Z scores, and the covariances are considered as edges of a network of coactivated clusters (nodes). Here it is validated by numerical simulation and demonstrated on real data used previously to demonstrate CBMA. Software to perform CBMAN is freely available.

Epilepsy and associated mortality in patients with multiple sclerosis.

BACKGROUND AND PURPOSE: We aimed to determine the prevalence of epilepsy in patients with multiple sclerosis (MS) at diagnosis, the risk of developing epilepsy after the diagnosis of MS and the relative risk of mortality associated with epilepsy. METHODS: We used the UK Clinical Practice Research Data-link to identify 2526 patients with incident MS and 9980 age-, sex- and index year-matched non-MS controls from 1997 to 2006. Logistic regression was used to estimate odds ratios [95% confidence interval (CI)] for epilepsy and Cox regression was used to estimate hazard ratios (HRs) (95% CI) for epilepsy and mortality. RESULTS: Patients with incident MS were on average 45 years old and 70.9% were female. At diagnosis, the prevalence of epilepsy in patients with MS was 1.30% compared with 0.57% in non-MS controls. At diagnosis, MS was associated with an adjusted odds ratio (95% CI) of 2.11 (1.36-3.27) for pre-existing epilepsy. Among epilepsy-free patients, the cumulative probabilities of developing epilepsy, first recorded within 10 years of the index date, were 2.77% for patients with MS and 0.90% for controls. MS was associated with an adjusted HR (95% CI) of 6.01 (2.94-12.29) for epilepsy. Among patients with MS, epilepsy was associated with an HR (95% CI) of 2.23 (1.02-4.84) for all-cause mortality. CONCLUSIONS: This population-based study found an increased prevalence of epilepsy in patients with MS at diagnosis when compared with non-MS controls and the risk of developing epilepsy was also higher following the MS diagnosis. Patients with MS with epilepsy had a higher risk of mortality compared with those without.

Coordinate based random effect size meta-analysis of neuroimaging studies.

Low power in neuroimaging studies can make them difficult to interpret, and Coordinate based meta-analysis (CBMA) may go some way to mitigating this issue. CBMA has been used in many analyses to detect where published functional MRI or voxel-based morphometry studies testing similar hypotheses report significant summary results (coordinates) consistently. Only the reported coordinates and possibly t statistics are analysed, and statistical significance of clusters is determined by coordinate density. Here a method of performing coordinate based random effect size meta-analysis and meta-regression is introduced. The algorithm (ClusterZ) analyses both coordinates and reported t statistic or Z score, standardised by the number of subjects. Statistical significance is determined not by coordinate density, but by a random effects meta-analyses of reported effects performed cluster-wise using standard statistical methods and taking account of censoring inherent in the published summary results. Type 1 error control is achieved using the false cluster discovery rate (FCDR), which is based on the false discovery rate. This controls both the family wise error rate under the null hypothesis that coordinates are randomly drawn from a standard stereotaxic space, and the proportion of significant clusters that are expected under the null. Such control is necessary to avoid propagating and even amplifying the very issues motivating the meta-analysis in the first place. ClusterZ is demonstrated on both numerically simulated data and on real data from reports of grey matter loss in multiple sclerosis (MS) and syndromes suggestive of MS, and of painful stimulus in healthy controls. The software implementation is available to download and use freely.

Decreased interferon-ß induced STAT-4 activation in immune cells and clinical outcome in multiple sclerosis.

OBJECTIVES: Interferon-ß (IFN-ß) is used in the treatment of multiple sclerosis (MS). IFN-ß activation of signal transduction and activation of transcription (STAT)-4 is linked to its immunomodulatory effects. Previous studies suggest a type I IFN deficit in immune cells of patients MS, but data on interferon-α/ß receptor (IFNAR) expression and the relationship with treatment response are conflicting. Here, we compare IFN-ß-mediated STAT4 activation in immune cells of untreated patients with MS and controls. MATERIALS AND METHODS: Peripheral blood mononuclear cells from 27 untreated patients with relapsing MS, obtained before the initiation of IFN-ß treatment, and 12 matched controls were treated in vitro with IFN-ß. Total and phosphorylated STAT4 (pSTAT4) and IFNAR were measured by flow cytometry and quantitative PCR. The patients were followed up for 5 years. RESULTS: pSTAT4 induction by IFN-ß was lower in patients with MS than in controls, as was expression of IFNAR. pSTAT4 expression did not correlate with the clinical outcome at 5 years, measured by EDSS change. There was a negative correlation between the baseline IFNAR1 mRNA levels and relapse rate. CONCLUSIONS: The results suggest decreased IFN-ß responsiveness in patients with MS, associated with reduced STAT4 activation and reduced IFNAR expression. This reduced responsiveness does not appear to affect the long-term clinical outcome of IFN-ß treatment.

Effects of pro-inflammatory cytokines on cannabinoid CB1 and CB2 receptors in immune cells.

AIMS: To investigate the regulation of cannabinoid receptors CB1 and CB2 on immune cells by pro-inflammatory cytokines and its potential relevance to the inflammatory neurological disease, multiple sclerosis (MS). CB1 and CB2 signalling may be anti-inflammatory and neuroprotective in neuroinflammatory diseases. Cannabinoids can suppress inflammatory cytokines but the effects of these cytokines on CB1 and CB2 expression and function are unknown. METHODS: Immune cells from peripheral blood were obtained from healthy volunteers and patients with MS. Expression of CB1 and CB2 mRNA in whole blood cells, peripheral blood mononuclear cells (PBMC) and T cells was determined by quantitative real-time polymerase chain reaction (qRT-PCR). Expression of CB1 and CB2 protein was determined by flow cytometry. CB1 and CB2 signalling in PBMC was determined by Western blotting for Erk1/2. RESULTS: Pro-inflammatory cytokines IL-1ß, IL-6 and TNF-α (the latter likely NF-κB dependently) can upregulate CB1 and CB2 on human whole blood and peripheral blood mononuclear cells (PBMC). We also demonstrate upregulation of CB1 and CB2 and increased IL-1ß, IL-6 and TNF-α mRNA in blood of patients with MS compared with controls. CONCLUSION: The levels of CB1 and CB2 can be upregulated by inflammatory cytokines, which can explain their increase in inflammatory conditions including MS.

The endocannabinoid system: a revolving plate in neuro-immune interaction in health and disease.

Studies of the last 40 years have brought to light an important physiological network, the endocannabinoid system. Endogenous and exogenous cannabinoids mediate their effects through activation of specific cannabinoid receptors. This modulatory homoeostatic system operates in the regulation of brain function and also in the periphery. The cannabinoid system has been shown to be involved in regulating the immune system. Studies examining the effect of cannabinoid-based drugs on immunity have shown that many cellular and cytokine mechanisms are modulated by these agents, thus raising the hypothesis that these compounds may be of value in the management of chronic inflammatory diseases. The special properties of endocannabinoids as neurotransmitters, their pleiotropic effects and the impact on immune function show that the endocannabinoid system represents a revolving plate of neural and immune interactions. In this paper, we outline current information on immune effects of cannabinoids in health and disease.

Central inflammation versus peripheral regulation in multiple sclerosis.

Th17 cells are a highly pro-inflammatory T-helper cell subset characterised by the expression of IL17. They have been implicated in a variety of allergic and autoimmune conditions. T-regulatory (Treg) cells, a subset of CD4 cells which express Foxp3, CD25, IL10 and TGFß, can suppress the activity of Th17 cells. In this study, we show that the circulating levels of Th17 and Treg cells in peripheral blood are correlated; furthermore, the expression of the pro-inflammatory cytokine IL17 and the anti-inflammatory cytokine IL10 by CD4 cells are also correlated. However, we found no clear correlation between cerebrospinal fluid (CSF) IL10 and IL17 cytokine levels in MS, approaching a negative correlation at the time of relapse, and an overall negative correlation between CSF IL17 and TGFß levels, suggesting a lack of central regulation of pro:anti-inflammatory balance in this demyelinating condition.

Randomized controlled trial of Sativex to treat detrusor overactivity in multiple sclerosis.

BACKGROUND: Bladder dysfunction is a common feature of multiple sclerosis (MS). OBJECTIVE: In this study we aimed to assess the efficacy, tolerability and safety of Sativex(®) (nabiximols) as an add-on therapy in alleviating bladder symptoms in patients with MS. METHODS: We undertook a 10-week, double-blind, randomized, placebo-controlled, parallel-group trial in 135 randomized subjects with MS and overactive bladder (OAB). RESULTS: The primary endpoint was the reduction in daily number of urinary incontinence episodes from baseline to end of treatment (8 weeks). Other endpoints included incidence of nocturia and urgency, overall bladder condition (OBC), daytime frequency, Incontinence Quality of Life (I-QOL), Patient's Global Impression of Change (PGIC) and volume voided. The primary endpoint showed little difference between Sativex and placebo. Four out of seven secondary endpoints were significantly in favour of Sativex: number of episodes of nocturia (adjusted mean difference -0.28, p = 0.010), OBC (-1.16, p = 0.001), number of voids/day (-0.85, p = 0.001) and PGIC (p = 0.005). Of the other endpoints, number of daytime voids was statistically significantly in favour of Sativex (-0.57, p = 0.044). The improvement in I-QOL was in favour of Sativex but did not reach statistical significance. CONCLUSIONS: Although the primary endpoint did not reach statistical significance, we conclude that Sativex did have some impact on the symptoms of overactive bladder in patients with MS, providing evidence of some improvement in symptoms associated with bladder dysfunction in these subjects.

Current and future disease-modifying therapies in multiple sclerosis.

The development of disease-modifying therapies (DMT) in multiple sclerosis (MS) has rapidly evolved over the last few years and continues to do so. Prior to the United States Food and Drug Administration approval of the immunomodulatory agent, interferon-beta1b in 1993, no other drug had been shown to alter the course of the disease in a controlled study of MS. At present, there are five licenced disease-modifying agents in MS - interferon-beta1b, interferon-beta1a, glatiramer acetate, natalizumab and mitoxantrone. All have shown significant therapeutic efficacy in large controlled trials. However, current therapies are only partially effective and are not free from adverse effects. Moreover, available DMTs are overwhelmingly biased in favour of those with relapsing-remitting disease. Effective treatment for progressive MS is severely limited, with only interferon-beta1b and mitoxantrone having licenced use in secondary progressive, but not primary progressive disease. Monoclonal antibodies, such as natalizumab selectively target immune pathways involved in the pathogenic process of MS. Alemtuzumab, daclizumab and rituximab are other notable monoclonal antibodies currently undergoing phase II and III trials in MS. Alemtuzumab has so far shown promising therapeutic benefit in relapsing disease, although immunological adverse effects have been a problem. Oral therapies have the benefit of improved tolerability and patient compliance compared with current parenteral treatments. Cladribine and fingolimod (FTY720) have shown encouraging results in their phase III clinical trials. It is also worth noting the evidence for starting DMT in patients with clinically isolated syndrome, whereby early treatment has shown to delay the onset of clinically definite MS in separate phase III studies.

Th17/Th1 phenotype in demyelinating disease.

BACKGROUND: Th17 cells are thought to contribute to the immunopathology of allergic and autoimmune conditions. Their role in multiple sclerosis (MS) pathology remains to be fully elucidated. OBJECTIVE: To assess peripheral blood Th17 responses in patients with MS compared to controls. METHODS: We isolated peripheral blood mononuclear cells from 41 MS patients and 23 healthy controls, which were then stimulated using phorbol ester and ionomycin, labelled for CD3, CD8, CD154, IL-17 and IFN-gamma and analysed using flow cytometry. RESULTS: Minimal IL-17 was detectable in unstimulated cells. Following stimulation with phorbol ester and ionomycin, PBMCs taken from MS patients in relapse developed a more inflammatory profile than those taken from controls or non-relapse patients, with greater expression of CD154, IL-17 and dual expression of IL-17/IFN-gamma. CONCLUSION: We suggest a greater tendency to Th17 and Th1/Th17 response to non-specific stimulation in MS patients in relapse compared to controls and non-relapse patients.

Plasma endocannabinoid levels in multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is a chronic inflammatory disease of the CNS. Therapies that affect the endocannabinoid (EC) system may have immunomodulatory, symptomatic and neuroprotective effects. AIM: The aim of this study was to determine how levels of EC and related compounds are altered in MS. METHODS: Plasma and whole blood were collected from 24 MS patients (10 relapsing-remitting (RR); 8 secondary-progressive (SP); 6 primary-progressive (PP); 19 females; 25-66 years) and 17 controls (10 females; 22-62 years). Plasma EC and related compounds were quantified by liquid chromatography-tandem mass spectrometry. Fatty acid amide hydrolase (FAAH), cannabinoid receptors CB(1) and CB(2) mRNA were measured by quantitative reverse transcriptase-polymerase chain reaction. RESULTS: Anandamide (AEA) and palmitoylethanolamide (PEA) were higher in RRMS compared to controls (p=0.001 and p=0.027). AEA, PEA and oleoylethanolamide were also increased in SPMS plasma (p=0.001, p=0.004, and p=0.005). PPMS patients had higher AEA plasma levels compared to controls (p=0.009). FAAH mRNA was decreased in SPMS (p=0.04) but not in RRMS or PPMS blood. CB(1) (p=0.012) and CB(2) mRNA (p=0.003) were increased in the PPMS. CONCLUSION: The EC system is altered in MS. It may be dynamically modulated depending on the subtype of the disease, but further studies with larger subgroups are needed to confirm this.

Glucocorticoids increase CD4CD25 cell percentage and Foxp3 expression in patients with multiple sclerosis.

OBJECTIVES: To determine whether percentages of CD4(+)CD25(high) T cells (a group of regulatory T cells, Treg) differ in patients with multiple sclerosis (MS) in relapse vs remission after glucocorticoid treatment and whether treatment for relapses changes Treg population and the expression of Foxp3, a key Treg-associated molecule. MATERIALS AND METHODS: Peripheral blood mononuclear cells (PBMC) were obtained from 20 patients with MS during relapse, just before and 2 days after starting steroid treatment (i.v. methylprednisolone 1 g/day for 3 days) and then 6 weeks after treatment. CD4(+)CD25(hi) cells were analysed by using flow cytometry. Cytokines were measured by using an ELISA and Foxp3, CD3 and CD25 expression by using quantitative real-time PCR. RESULTS: The percentage of CD4(+)CD25(hi) cells, plasma IL-10 and Foxp3/CD3 ratio increased 48 h after methylprednisolone initiation and returned to baseline values by 6 weeks post-treatment. CONCLUSIONS: Results suggest that glucocorticoids increase Treg cell functional molecules and percentages. This may be a mechanism whereby steroids expedite recovery from MS relapses.

Disconnection as a mechanism for cognitive dysfunction in multiple sclerosis.

Disconnection of cognitively important processing regions by injury to the interconnecting white matter provides a potential mechanism for cognitive dysfunction in multiple sclerosis. The contribution of tract-specific white matter injury to dysfunction in different cognitive domains in patients with multiple sclerosis has not previously been studied. We apply tract-based spatial statistics (TBSS) to diffusion tensor imaging (DTI) in a cohort of multiple sclerosis patients to identify loci where reduced white matter tract fractional anisotropy (FA) predicts impaired performance in cognitive testing. Thirty-seven multiple sclerosis patients in remission (median age 43.5 years; Expanded Disability Status Scale range 1.5-6.5; 35 relapsing remitting, two secondary-progressive) underwent 3 T MRI including high-resolution DTI. Multiple sclerosis patients underwent formal testing of performance in multiple cognitive domains. Normalized cognitive scores were used for voxel-wise statistical analysis using TBSS, while treating age as a covariate of no interest. Permutation-based inference on cluster size (t > 2, P <0.05 corrected) was used to correct for multiple comparisons. Statistical mapping revealed differential patterns of FA reduction for tests of sustained attention, working memory and processing speed, visual working memory and verbal learning and recall. FA was not associated with frontal lobe function or visuospatial perception. Cognitively relevant tract localizations only partially overlapped with areas of high FLAIR lesion probability, confirming the contribution of normal-appearing white matter abnormality to cognitive dysfunction. Of note, tract localizations showing significant associations with cognitive impairment were found to interconnect cortical regions thought to be involved in processing in these cognitive domains, or involve possible compensatory processing pathways. This suggests that TBSS reveals functionally relevant tract injury underlying cognitive dysfunction in patients with multiple sclerosis.

Stroop performance in multiple sclerosis: information processing, selective attention, or executive functioning?

Cognitive impairments in information processing speed, attention and executive functioning are widely reported in patients with multiple sclerosis (MS). Several studies have identified impaired performance on the Stroop test in people with MS, yet uncertainty remains over the cause of this phenomenon. In this study, 25 patients with MS were assessed with a neuropsychological test battery including a computerized Stroop test and a computerized test of information processing speed, the Graded Conditional Discrimination Tasks (GCDT). The patient group was compared with an individually age, sex and estimated premorbid IQ-matched healthy control group. The patients' reaction times (RTs) were significantly longer than those of the controls on all Stroop test trials and there was a significantly enhanced absolute (RT(incongruent)-RT(neutral)) and relative (100 x [RT(incongruent)-RT(neutral)]/RT(neutral)) Stroop interference effect for the MS group. The linear function relating RT to stimulus complexity in the GCDT was significantly steeper in the patient group, indicating slowed information processing. The results are discussed with reference to the difference engine model, a theory of diversity in speeded cognition. It is concluded that, in the assessment of people with MS, great caution must be used in the interpretation of performance on neuropsychological tests which rely on RT as the primary measure.

Eye movement involvement in Parry-Romberg Syndrome: a clinicopathologic case report.

We report the case of a 38-year-old woman who developed a progressive bilateral disease in which the eye motility disorder-diplopia-is the outstanding feature over a period of 12 years. The muscle biopsy of the medial rectus muscle did not show any trace of striated muscle. To the best of our knowledge, this is the first pathological report in an affected extraocular muscle of a patient with Parry-Romberg syndrome (PRS). Previous rare reports of diplopia in PRS have been attributed to enophthalmos, progressive atrophy of the orbit, ocular motor nerve dysfunction, or mechanical restrictions.