Central post-stroke pain--a controlled trial of amitriptyline and carbamazepine

Efficacy and safety of pregabalin vs carbamazepine in patients with central post-stroke pain

OBJECTIVE

To compare the efficacy and safety of pregabalin and carbamazepine in patients with central post-stroke pain (CPSP).

METHODS

Patients included in the study were randomly assigned to either flexible-dose pregabalin treatment group or carbamazepine treatment group. The primary efficacy variable was face visual analog scale (F-VAS), the second efficacy assessment was used to assess the effect of treatment on mental health by Hamilton anxiety scale (HAMA) and Hamilton depression scale (HAMD).

RESULTS

The mean baseline pain score F-VAS was 6.47 in the pregabalin group and 6.58 in carbamazepine treatment group. F-VAS was significantly lower in the pregabalin group (1.64) than (3.94) carbamazepine treatment group after treatment. Pregabalin was significantly superior to carbamazepine in endpoint assessments on the HAMA and HAMD after treatment. F-VAS and HAMD were showed efficacy as early as week 2 and maintained for whole duration of the study. The average pregabalin dose in the 12-week study was 214.6 (150-375) mg/day. The mean dose (range) of carbamazepine received by the patients was 275.0 (200-400) mg/day. Mild or moderate, typically transient, somnolence and dizziness were the most common adverse events (AES). The differences of the side effects between the two groups were not significant.

CONCLUSIONS

Pregabalin, but not carbamazepine, may be effective in improving F-VAS, HAMA and HAMD in patients with CPSP.

Synthesis technique and electron beam damage study of nanometer-thin single-crystalline thymine

Samples suitable for electron diffraction studies must satisfy certain characteristics such as having a thickness in the range of 10-100 nm. We report, to our knowledge, the first successful synthesis technique of nanometer-thin sheets of single-crystalline thymine suitable for electron diffraction and spectroscopy studies. This development provides a well-defined system to explore issues related to UV photochemistry of DNA and high intrinsic stability essential to maintaining integrity of genetic information. The crystals are grown using the evaporation technique, and the nanometer-thin sheets are obtained via microtoming. The sample is characterized via x-ray diffraction and is subsequently studied using electron diffraction via a transmission electron microscope. Thymine is found to be more radiation resistant than similar molecular moieties (e.g., carbamazepine) by a factor of 5. This raises interesting questions about the role of the fast relaxation processes of electron scattering-induced excited states, extending the concept of radiation hardening beyond photoexcited states. The high stability of thymine in particular opens the door for further studies of these ultrafast relaxation processes giving rise to the high stability of DNA to UV radiation.

Central neuropathic pain

Central neuropathic pain arises from a lesion or disease of the central somatosensory nervous system such as brain injury, spinal cord injury, stroke, multiple sclerosis or related neuroinflammatory conditions. The incidence of central neuropathic pain differs based on its underlying cause. Individuals with spinal cord injury are at the highest risk; however, central post-stroke pain is the most prevalent form of central neuropathic pain worldwide. The mechanisms that underlie central neuropathic pain are not fully understood, but the pathophysiology likely involves intricate interactions and maladaptive plasticity within spinal circuits and brain circuits associated with nociception and antinociception coupled with neuronal hyperexcitability. Modulation of neuronal activity, neuron-glia and neuro-immune interactions and targeting pain-related alterations in brain connectivity, represent potential therapeutic approaches. Current evidence-based pharmacological treatments include antidepressants and gabapentinoids as first-line options. Non-pharmacological pain management options include self-management strategies, exercise and neuromodulation. A comprehensive pain history and clinical examination form the foundation of central neuropathic pain classification, identification of potential risk factors and stratification of patients for clinical trials. Advanced neurophysiological and neuroimaging techniques hold promise to improve the understanding of mechanisms that underlie central neuropathic pain and as predictive biomarkers of treatment outcome.

Neuropathic Pain in the Emergency Setting: Diagnosis and Management

Neuropathic pain, traditionally considered a chronic condition, is increasingly encountered in the emergency department (ED), accounting for approximately 20% of patients presenting with pain. Understanding the physiology and key clinical presentations of neuropathic pain is crucial for ED physicians to provide optimal treatment. While diagnosing neuropathic pain can be challenging, emphasis should be placed on obtaining a comprehensive medical history and conducting a thorough clinical examination. Patients often describe neuropathic pain as a burning or shock-like sensation, leading them to seek care in the ED after ineffective relief from common analgesics such as paracetamol and NSAIDs. Collaboration between emergency medicine specialists, neurologists, and pain management experts can contribute to the development of evidence-based guidelines specifically tailored for the emergency department setting. This article provides a concise overview of the common clinical manifestations of neuropathic pain that may prompt patients to seek emergency care.

Global Research Trends and Hotspots Analysis of the Scientific Production of Amitriptyline: A Bibliometric Approach

Amitriptyline was first introduced as a medication to treat depression. Over time, this substance has been used to treat other conditions, such as gastrointestinal disorders, fibromyalgia, neuropathic pain, and analgesia, among others. However, there are no published studies that provide a broad view of the possible motivations that have led to changes in the use of amitriptyline. In this study, we have identified the landscape of use for amitriptyline based on knowledge mapping of the 100 most-cited articles about this drug. We searched Web of Science Core Collection without time and language restrictions. We obtained 14,446 results, but we only used the 100 most-cited articles that had amitriptyline as the object of study. We collected the following information from each article: authors, country of the corresponding authors, year of publication, citation count, citation density (number of citations per year), and keywords. In addition, we seek to map in the chosen articles study design and research findings. We found that since 1980, the use of amitriptyline has expanded beyond depression, moving to off-label use to treat a variety of diseases and conditions, including post-herpetic neuralgia, neuropathic pain, primary fibrosis, fibromyalgia, and migraine, can be considered a drug with more clinical applicability than its original clinical indication.

Pharmacological, non-invasive brain stimulation and psychological interventions, and their combination, for treating depression after stroke

BACKGROUND

Depression is an important morbidity associated with stroke that impacts on recovery, yet is often undetected or inadequately treated.

OBJECTIVES

To evaluate the benefits and harms of pharmacological intervention, non-invasive brain stimulation, psychological therapy, or combinations of these to treat depression after stroke.

SEARCH METHODS

This is a living systematic review. We search for new evidence every two months and update the review when we identify relevant new evidence. Please refer to the Cochrane Database of Systematic Reviews for the current status of this review. We searched the Specialised Registers of Cochrane Stroke, and Cochrane Depression Anxiety and Neurosis, CENTRAL, MEDLINE, Embase, five other databases, two clinical trials registers, reference lists and conference proceedings (February 2022). We contacted study authors.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing: 1) pharmacological interventions with placebo; 2) non-invasive brain stimulation with sham stimulation or usual care; 3) psychological therapy with usual care or attention control; 4) pharmacological intervention and psychological therapy with pharmacological intervention and usual care or attention control; 5) pharmacological intervention and non-invasive brain stimulation with pharmacological intervention and sham stimulation or usual care; 6) non-invasive brain stimulation and psychological therapy versus sham brain stimulation or usual care and psychological therapy; 7) pharmacological intervention and psychological therapy with placebo and psychological therapy; 8) pharmacological intervention and non-invasive brain stimulation with placebo and non-invasive brain stimulation; and 9) non-invasive brain stimulation and psychological therapy versus non-invasive brain stimulation and usual care or attention control, with the intention of treating depression after stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias, and extracted data from included studies. We calculated mean difference (MD) or standardised mean difference (SMD) for continuous data, and risk ratio (RR) for dichotomous data, with 95% confidence intervals (CIs). We assessed heterogeneity using the I² statistic and certainty of the evidence according to GRADE.

MAIN RESULTS

We included 65 trials (72 comparisons) with 5831 participants. Data were available for: 1) 20 comparisons; 2) nine comparisons; 3) 25 comparisons; 4) three comparisons; 5) 14 comparisons; and 6) one comparison. We found no trials for comparisons 7 to 9. Comparison 1: Pharmacological interventions Very low-certainty evidence from eight trials suggests pharmacological interventions decreased the number of people meeting the study criteria for depression (RR 0.70, 95% CI 0.55 to 0.88; P = 0.002; 8 RCTs; 1025 participants) at end of treatment and very low-certainty evidence from six trials suggests that pharmacological interventions decreased the number of people with inadequate response to treatment (RR 0.47, 95% CI 0.32 to 0.70; P = 0.0002; 6 RCTs; 511 participants) compared to placebo. More adverse events related to the central nervous system (CNS) (RR 1.55, 95% CI 1.12 to 2.15; P = 0.008; 5 RCTs; 488 participants; very low-certainty evidence) and gastrointestinal system (RR 1.62, 95% CI 1.19 to 2.19; P = 0.002; 4 RCTs; 473 participants; very low-certainty evidence) were noted in the pharmacological intervention than in the placebo group. Comparison 2: Non-invasive brain stimulation Very low-certainty evidence from two trials show that non-invasive brain stimulation had little to no effect on the number of people meeting the study criteria for depression (RR 0.67, 95% CI 0.39 to 1.14; P = 0.14; 2 RCTs; 130 participants) and the number of people with inadequate response to treatment (RR 0.84, 95% CI 0.52, 1.37; P = 0.49; 2 RCTs; 130 participants) compared to sham stimulation. Non-invasive brain stimulation resulted in no deaths. Comparison 3: Psychological therapy Very low-certainty evidence from six trials suggests that psychological therapy decreased the number of people meeting the study criteria for depression at end of treatment (RR 0.77, 95% CI 0.62 to 0.95; P = 0.01; 521 participants) compared to usual care/attention control. No trials of psychological therapy reported on the outcome inadequate response to treatment. No differences in the number of deaths or adverse events were found in the psychological therapy group compared to the usual care/attention control group. Comparison 4: Pharmacological interventions with psychological therapy No trials of this combination reported on the primary outcomes. Combination therapy resulted in no deaths. Comparison 5: Pharmacological interventions with non-invasive brain stimulation Non-invasive brain stimulation with pharmacological intervention reduced the number of people meeting study criteria for depression at end of treatment (RR 0.77, 95% CI 0.64 to 0.91; P = 0.002; 3 RCTs; 392 participants; low-certainty evidence) but not the number of people with inadequate response to treatment (RR 0.95, 95% CI 0.69 to 1.30; P = 0.75; 3 RCTs; 392 participants; very low-certainty evidence) compared to pharmacological therapy alone. Very low-certainty evidence from five trials suggest no difference in deaths between this combination therapy (RR 1.06, 95% CI 0.27 to 4.16; P = 0.93; 487 participants) compared to pharmacological therapy intervention and sham stimulation or usual care. Comparison 6: Non-invasive brain stimulation with psychological therapy No trials of this combination reported on the primary outcomes.

AUTHORS' CONCLUSIONS

Very low-certainty evidence suggests that pharmacological, psychological and combination therapies can reduce the prevalence of depression while non-invasive brain stimulation had little to no effect on the prevalence of depression. Pharmacological intervention was associated with adverse events related to the CNS and the gastrointestinal tract. More research is required before recommendations can be made about the routine use of such treatments.

Antidepressants for pain management in adults with chronic pain: a network meta-analysis

BACKGROUND

Chronic pain is common in adults, and often has a detrimental impact upon physical ability, well-being, and quality of life. Previous reviews have shown that certain antidepressants may be effective in reducing pain with some benefit in improving patients' global impression of change for certain chronic pain conditions. However, there has not been a network meta-analysis (NMA) examining all antidepressants across all chronic pain conditions.

OBJECTIVES

To assess the comparative efficacy and safety of antidepressants for adults with chronic pain (except headache).

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, LILACS, AMED and PsycINFO databases, and clinical trials registries, for randomised controlled trials (RCTs) of antidepressants for chronic pain conditions in January 2022.

SELECTION CRITERIA

We included RCTs that examined antidepressants for chronic pain against any comparator. If the comparator was placebo, another medication, another antidepressant, or the same antidepressant at different doses, then we required the study to be double-blind. We included RCTs with active comparators that were unable to be double-blinded (e.g. psychotherapy) but rated them as high risk of bias. We excluded RCTs where the follow-up was less than two weeks and those with fewer than 10 participants in each arm.  DATA COLLECTION AND ANALYSIS: Two review authors separately screened, data extracted, and judged risk of bias. We synthesised the data using Bayesian NMA and pairwise meta-analyses for each outcome and ranked the antidepressants in terms of their effectiveness using the surface under the cumulative ranking curve (SUCRA). We primarily used Confidence in Meta-Analysis (CINeMA) and Risk of Bias due to Missing Evidence in Network meta-analysis (ROB-MEN) to assess the certainty of the evidence. Where it was not possible to use CINeMA and ROB-MEN due to the complexity of the networks, we used GRADE to assess the certainty of the evidence. Our primary outcomes were substantial (50%) pain relief, pain intensity, mood, and adverse events. Our secondary outcomes were moderate pain relief (30%), physical function, sleep, quality of life, Patient Global Impression of Change (PGIC), serious adverse events, and withdrawal.

MAIN RESULTS

This review and NMA included 176 studies with a total of 28,664 participants. The majority of studies were placebo-controlled (83), and parallel-armed (141). The most common pain conditions examined were fibromyalgia (59 studies); neuropathic pain (49 studies) and musculoskeletal pain (40 studies). The average length of RCTs was 10 weeks. Seven studies provided no useable data and were omitted from the NMA. The majority of studies measured short-term outcomes only and excluded people with low mood and other mental health conditions. Across efficacy outcomes, duloxetine was consistently the highest-ranked antidepressant with moderate- to high-certainty evidence. In duloxetine studies, standard dose was equally efficacious as high dose for the majority of outcomes. Milnacipran was often ranked as the next most efficacious antidepressant, although the certainty of evidence was lower than that of duloxetine. There was insufficient evidence to draw robust conclusions for the efficacy and safety of any other antidepressant for chronic pain.  Primary efficacy outcomes Duloxetine standard dose (60 mg) showed a small to moderate effect for substantial pain relief (odds ratio (OR) 1.91, 95% confidence interval (CI) 1.69 to 2.17; 16 studies, 4490 participants; moderate-certainty evidence) and continuous pain intensity (standardised mean difference (SMD) -0.31, 95% CI -0.39 to -0.24; 18 studies, 4959 participants; moderate-certainty evidence). For pain intensity, milnacipran standard dose (100 mg) also showed a small effect (SMD -0.22, 95% CI -0.39 to 0.06; 4 studies, 1866 participants; moderate-certainty evidence). Mirtazapine (30 mg) had a moderate effect on mood (SMD -0.5, 95% CI -0.78 to -0.22; 1 study, 406 participants; low-certainty evidence), while duloxetine showed a small effect (SMD -0.16, 95% CI -0.22 to -0.1; 26 studies, 7952 participants; moderate-certainty evidence); however it is important to note that most studies excluded participants with mental health conditions, and so average anxiety and depression scores tended to be in the 'normal' or 'subclinical' ranges at baseline already. Secondary efficacy outcomes Across all secondary efficacy outcomes (moderate pain relief, physical function, sleep, quality of life, and PGIC), duloxetine and milnacipran were the highest-ranked antidepressants with moderate-certainty evidence, although effects were small. For both duloxetine and milnacipran, standard doses were as efficacious as high doses. Safety There was very low-certainty evidence for all safety outcomes (adverse events, serious adverse events, and withdrawal) across all antidepressants. We cannot draw any reliable conclusions from the NMAs for these outcomes.

AUTHORS' CONCLUSIONS

Our review and NMAs show that despite studies investigating 25 different antidepressants, the only antidepressant we are certain about for the treatment of chronic pain is duloxetine. Duloxetine was moderately efficacious across all outcomes at standard dose. There is also promising evidence for milnacipran, although further high-quality research is needed to be confident in these conclusions. Evidence for all other antidepressants was low certainty. As RCTs excluded people with low mood, we were unable to establish the effects of antidepressants for people with chronic pain and depression. There is currently no reliable evidence for the long-term efficacy of any antidepressant, and no reliable evidence for the safety of antidepressants for chronic pain at any time point.

The Potential Role of Etanercept in the Management of Post-stroke Pain: A Literature Review

Strokes are the second leading cause of death and disability worldwide. The brain injury resulting from stroke produces a persistent neuroinflammatory response in the brain, resulting in a spectrum of neurologic dysfunction affecting stroke survivors chronically, also known as post-stroke pain. Excess production of tumor necrosis factor alpha (TNF alpha) in the cerebrospinal fluid (CSF) of stroke survivors has been implicated in post-stroke pain. Therefore, this literature review aims to assess and review the role of perispinal etanercept in the management of post-stroke pain. Several studies have shown statistically significant evidence that etanercept, a TNF alpha inhibitor, can reduce symptoms present in post-stroke syndrome by targeting the excess TNF alpha produced in the CSF. Studies have also shown improvements in not only post-stroke pain but also in traumatic brain injury and dementia. Further research is needed to explore the effects of TNF alpha on stroke prognosis and determine the optimal frequency and duration of etanercept treatment for post-stroke pain.

Stellate Ganglion Blocks for Refractory Central Poststroke Pain: A Case Series

Central poststroke pain (CPSP) is a neuropathic pain secondary to cerebrovascular accidents. This is characterized by pain and other sensory abnormalities, which correspond with the area of the injured brain. Despite advancements in therapeutic options, this clinical entity is still challenging to treat. We present 5 patients with CPSP, who were refractory to pharmacotherapy and were successfully managed with stellate ganglion blocks. A significant decrease in pain scores and improvement in functional disabilities were noted in all patients following the intervention.

Pharmacotherapies for Central Post-Stroke Pain: A Systematic Review and Network Meta-Analysis

Background

Central post-stroke pain (CPSP) is a common condition. Several pharmacotherapies have been applied in practice. However, the comparative effectiveness among these pharmacotherapies is unknown.

Aim

The aim of this study is to study the comparative effectiveness among differential pharmacotherapies for CPSP through a network meta-analysis.

Methods

We searched MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials (CENTRAL), and Web of Science from inception to 30 March 2022, without any language restriction. Two reviewers independently screened the retrieved articles, extracted data, and evaluated the risk of bias (RoB). The outcome of interest of the study was the change in the scores of pain intensity scales. We estimated standard mean differences (SMDs) between treatments and calculated corresponding 95% CIs.

Results

Thirteen randomized controlled trials (529 participants) were included after a screen of 1774 articles. Compared with placebo, pamidronate (SMD -2.43, 95% CI -3.54 to -1.31; P − score = 0.93), prednisone (SMD -2.38, 95% CI -3.09 to -1.67; P − score = 0.92), levetiracetam (SMD -2.11, 95% CI -2.97 to -1.26; P − score = 0.87), lamotrigine (SMD -1.39, 95% CI -2.21 to -0.58; P − score = 0.73), etanercept (SMD -0.92, 95% CI -1.8 to -0.03; P − score = 0.59), and pregabalin (SMD -0.46, 95% CI -0.71 to -0.22; P − score = 0.41) had significantly better treatment effect. Pamidronate, prednisone, and levetiracetam ranked as the first three most effective treatments. In subgroup analyses, prednisone, levetiracetam, lamotrigine, and pregabalin were more effective than placebo as oral pharmacotherapies, while etanercept was more effective than placebo as injectable pharmacotherapy.

Conclusions

Our study confirmed that pamidronate, prednisone, and guideline-recommended anticonvulsants were effective for reducing pain intensity for CPSP. Pamidronate and prednisone showed better effect than other pharmacotherapies, which warrants further investigation.

The Management of Poststroke Thalamic Pain: Update in Clinical Practice

Poststroke thalamic pain (PS-TP), a type of central poststroke pain, has been challenged to improve the rehabilitation outcomes and quality of life after a stroke. It has been shown in 2.7–25% of stroke survivors; however, the treatment of PS-TP remains difficult, and in majority of them it often failed to manage the pain and hypersensitivity effectively, despite the different pharmacotherapies as well as invasive interventions. Central imbalance, central disinhibition, central sensitization, other thalamic adaptative changes, and local inflammatory responses have been considered as its possible pathogenesis. Allodynia and hyperalgesia, as well as the chronic sensitization of pain, are mainly targeted in the management of PS-TP. Commonly recommended first- and second-lines of pharmacological therapies, including traditional medications, e.g., antidepressants, anticonvulsants, opioid analgesics, and lamotrigine, were more effective than others. Nonpharmacological interventions, such as transcranial magnetic or direct current brain stimulations, vestibular caloric stimulation, epidural motor cortex stimulation, and deep brain stimulation, were effective in some cases/small-sized studies and can be recommended in the management of therapy-resistant PS-TP. Interestingly, the stimulation to other areas, e.g., the motor cortex, periventricular/periaqueductal gray matter, and thalamus/internal capsule, showed more effect than the stimulation to the thalamus alone. Further studies on brain or spinal stimulation are required for evidence.

Brazilian Academy of Neurology practice guidelines for stroke rehabilitation: part I

The Guidelines for Stroke Rehabilitation are the result of a joint effort by the Scientific Department of Neurological Rehabilitation of the Brazilian Academy of Neurology aiming to guide professionals involved in the rehabilitation process to reduce functional disability and increase individual autonomy. Members of the group participated in web discussion forums with predefined themes, followed by videoconference meetings in which issues were discussed, leading to a consensus. These guidelines, divided into two parts, focus on the implications of recent clinical trials, systematic reviews, and meta-analyses in stroke rehabilitation literature. The main objective was to guide physicians, physiotherapists, speech therapists, occupational therapists, nurses, nutritionists, and other professionals involved in post-stroke care. Recommendations and levels of evidence were adapted according to the currently available literature. Part I discusses topics on rehabilitation in the acute phase, as well as prevention and management of frequent conditions and comorbidities after stroke.

Central Neuropathic Pain Syndromes: Current and Emerging Pharmacological Strategies

Central neuropathic pain is caused by a disease or lesion of the brain or spinal cord. It is difficult to predict which patients will develop central pain syndromes after a central nervous system injury, but depending on the etiology, lifetime prevalence may be greater than 50%. The resulting pain is often highly distressing and difficult to treat, with no specific treatment guidelines currently available. This narrative review discusses mechanisms contributing to central neuropathic pain, and focuses on pharmacological approaches for managing common central neuropathic pain conditions such as central post-stroke pain, spinal cord injury-related pain, and multiple sclerosis-related neuropathic pain. Tricyclic antidepressants, serotonin-norepinephrine reuptake inhibitors, and gabapentinoids have some evidence for efficacy in central neuropathic pain. Medications from other pharmacologic classes may also provide pain relief, but current evidence is limited. Certain non-pharmacologic approaches, neuromodulation in particular, may be helpful in refractory cases. Emerging data suggest that modulating the primary afferent input may open new horizons for the treatment of central neuropathic pain. For most patients, effective treatment will likely require a multimodal therapy approach.

Pharmacotherapy to Manage Central Post-Stroke Pain

Central post-stroke pain is a chronic neuropathic pain syndrome following a cerebrovascular accident. The development of central post-stroke pain is estimated to occur in 8 to 55% of stroke patients and is described as constant or intermittent neuropathic pain accompanied by dysesthesia of temperature and/or pressure sensations. These pain and sensory deficits are within the area of the body corresponding to the stroke lesion. The onset of pain is usually gradual, though it can develop either immediately after stroke or years after. Given the diversity in its clinical presentation, central post-stroke pain is a challenging diagnosis of exclusion. Furthermore, central post-stroke pain is often resistant to pharmacological treatment options and a clear therapeutic algorithm has not been established. Based on current evidence, amitriptyline, lamotrigine, and gabapentinoids should be used as first-line pharmacotherapy options when central post-stroke pain is suspected. Other drugs, such as fluvoxamine, steroids, and Intravenous infusions of lidocaine, ketamine, or even propofol, can be considered in intractable cases. In addition, interventional therapies such as motor cortex stimulation or transcranial magnetic stimulation have been shown to provide relief in difficult-to-treat patients.

Pharmacological treatment of central neuropathic pain: consensus of the Brazilian Academy of Neurology

ABSTRACT Background: Central neuropathic pain (CNP) is often refractory to available therapeutic strategies and there are few evidence-based treatment options. Many patients with neuropathic pain are not diagnosed or treated properly. Thus, consensus-based recommendations, adapted to the available drugs in the country, are necessary to guide clinical decisions. Objective: To develop recommendations for the treatment of CNP in Brazil. Methods: Systematic review, meta-analysis, and specialists opinions considering efficacy, adverse events profile, cost, and drug availability in public health. Results: Forty-four studies on CNP treatment were found, 20 were included in the qualitative analysis, and 15 in the quantitative analysis. Medications were classified as first-, second-, and third-line treatment based on systematic review, meta-analysis, and expert opinion. As first-line treatment, gabapentin, duloxetine, and tricyclic antidepressants were included. As second-line, venlafaxine, pregabalin for CND secondary to spinal cord injury, lamotrigine for CNP after stroke, and, in association with first-line drugs, weak opioids, in particular tramadol. For refractory patients, strong opioids (methadone and oxycodone), cannabidiol/delta-9-tetrahydrocannabinol, were classified as third-line of treatment, in combination with first or second-line drugs and, for central nervous system (CNS) in multiple sclerosis, dronabinol. Conclusions: Studies that address the treatment of CNS are scarce and heterogeneous, and a significant part of the recommendations is based on experts opinions. The CNP approach must be individualized, taking into account the availability of medication, the profile of adverse effects, including addiction risk, and patients' comorbidities.

Prevalence and Management Challenges in Central Post-Stroke Neuropathic Pain: A Systematic Review and Meta-analysis

Introduction

Central post-stroke pain (CPSP) is defined as the neuropathic pain that arises either acutely or in the chronic phase of a cerebrovascular event and is a result of central lesions of the somatosensory tract. The aim of this systematic review and meta-analysis was to establish the prevalence of CPSP, to describe its characteristics, and to discuss the associated management challenges.

Methods

After a systematic Medline search, we identified 69 papers eligible to be included.

Results

The pooled prevalence of CPSP in patients with stroke at any location was 11% (95% CI 7–18%), which can increase to more than 50% in the subgroups of patients with medullary or thalamic strokes. CPSP onset coincides with stroke occurrence in 26% of patients (95% CI 18–35%); CPSP manifests within a month since symptom onset in 31% of patients (95% CI 22–42%), and occurs between the first month and the first year in 41% of patients (95% CI 33.9–49.0%). CPSP develops more than 12 months after stroke onset in 5% of patients (95% CI 3–8%).

Conclusions

Clinicians should look for any evidence of central neuropathic pain for at least 12 months after stroke. Both pharmacological and non-pharmacological interventions can be used for the management of CPSP. Lamotrigine has the strongest evidence (Level II of evidence, derived from small randomized controlled trials) for being effective in the management of CPSP. Future research should focus on well-designed trials of pharmacological and non-pharmacological interventions aiming to relief CPSP, which is a very common but often neglected pain syndrome.

Electronic supplementary material

The online version of this article (10.1007/s12325-020-01388-w) contains supplementary material, which is available to authorized users.

Pharmacological, psychological and non-invasive brain stimulation interventions for preventing depression after stroke

BACKGROUND

Depression is an important consequence of stroke that influences recovery yet often is not detected, or is inadequately treated. This is an update and expansion of a Cochrane Review first published in 2004 and previously updated in 2008.

OBJECTIVES

The primary objective is to test the hypothesis that pharmacological, psychological therapy, non-invasive brain stimulation, or combinations of these interventions reduce the incidence of diagnosable depression after stroke. Secondary objectives are to test the hypothesis that pharmacological, psychological therapy, non-invasive brain stimulation or combinations of these interventions reduce levels of depressive symptoms and dependency, and improve physical functioning after stroke. We also aim to determine the safety of, and adherence to, the interventions.

SEARCH METHODS

We searched the Specialised Register of Cochrane Stroke and the Cochrane Depression Anxiety and Neurosis (last searched August 2018). In addition, we searched the following databases; Cochrane Central Register of Controlled Trials, CENTRAL (the Cochrane Library, 2018, Issue 8), MEDLINE (1966 to August 2018), Embase (1980 to August 2018), PsycINFO (1967 to August 2018), CINAHL (1982 to August 2018) and three Web of Science indexes (2002 to August 2018). We also searched reference lists, clinical trial registers (World Health Organization International Clinical Trials Registry Platform (WHO ICTRP); to August 2018 and ClinicalTrials.gov; to August 2018), conference proceedings; we also contacted study authors.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing: 1) pharmacological interventions with placebo; 2) one of various forms of psychological therapy with usual care and/or attention control; 3) one of various forms of non-invasive brain stimulation with sham stimulation or usual care; 4) a pharmacological intervention and one of various forms of psychological therapy with a pharmacological intervention and usual care and/or attention control; 5) non-invasive brain stimulation and pharmacological intervention with a pharmacological intervention and sham stimulation or usual care; 6) pharmacological intervention and one of various forms of psychological therapy with placebo and psychological therapy; 7) pharmacological intervention and non-invasive brain stimulation with placebo plus non-invasive brain stimulation; 8) non-invasive brain stimulation and one of various forms of psychological therapy versus non-invasive brain stimulation plus usual care and/or attention control; and 9) non-invasive brain stimulation and one of various forms of psychological therapy versus sham brain stimulation or usual care plus psychological therapy, with the intention of preventing depression after stroke.

DATA COLLECTION AND ANALYSIS

Review authors independently selected studies, assessed risk of bias, and extracted data from all included studies. We calculated mean difference (MD) or standardised mean difference (SMD) for continuous data and risk ratio (RR) for dichotomous data with 95% confidence intervals (CIs). We assessed heterogeneity using the I² statistic and assessed the certainty of evidence using GRADE.

MAIN RESULTS

We included 19 RCTs (21 interventions), with 1771 participants in the review. Data were available for 12 pharmacological trials (14 interventions) and seven psychological trials. There were no trials of non-invasive brain stimulation compared with sham stimulation or usual care, a combination of pharmacological intervention and one of various forms of psychological therapy with placebo and psychological therapy, or a combination of non-invasive brain stimulation and a pharmacological intervention with a pharmacological intervention and sham stimulation or usual care to prevent depression after stroke. Treatment effects were observed on the primary outcome of meeting the study criteria for depression at the end of treatment: there is very low-certainty evidence from eight trials (nine interventions) that pharmacological interventions decrease the number of people meeting the study criteria for depression (RR 0.50, 95% CI 0.37 to 0.68; 734 participants) compared to placebo. There is very low-certainty evidence from two trials that psychological interventions reduce the proportion of people meeting the study criteria for depression (RR 0.68, 95% CI 0.49 to 0.94, 607 participants) compared to usual care and/or attention control. Eight trials (nine interventions) found no difference in death and other adverse events between pharmacological intervention and placebo groups (RR 1.25, 95% CI 0.32 to 4.91; 496 participants) based on very low-certainty evidence. Five trials found no difference in psychological intervention and usual care and/or attention control groups for death and other adverse events (RR 1.18, 95% CI 0.73 to 1.91; 975 participants) based on very low-certainty evidence.

AUTHORS' CONCLUSIONS

The available evidence suggests that pharmacological interventions and psychological therapy may prevent depression and improve mood after stroke. However, there is very low certainty in these conclusions because of the very low-certainty evidence. More trials are required before reliable recommendations can be made about the routine use of such treatments after stroke.

Pharmacological, psychological, and non-invasive brain stimulation interventions for treating depression after stroke

BACKGROUND

Depression is an important morbidity associated with stroke that impacts on recovery yet often undetected or inadequately treated. This is an update and expansion of a Cochrane Review first published in 2004 and updated in 2008.

OBJECTIVES

Primary objective • To determine whether pharmacological therapy, non-invasive brain stimulation, psychological therapy, or combinations of these interventions reduce the prevalence of diagnosable depression after stroke Secondary objectives • To determine whether pharmacological therapy, non-invasive brain stimulation, psychological therapy, or combinations of these interventions reduce levels of depressive symptoms, improve physical and neurological function and health-related quality of life, and reduce dependency after stroke • To assess the safety of and adherence to such treatments SEARCH METHODS: We searched the Specialised Registers of Cochrane Stroke and Cochrane Depression Anxiety and Neurosis (last searched August 2018), the Cochrane Central Register of Controlled Trials (CENTRAL; 2018, Issue 1), in the Cochrane Library, MEDLINE (1966 to August 2018), Embase (1980 to August 2018), the Cumulative Index to Nursing and Alllied Health Literature (CINAHL) (1982 to August 2018), PsycINFO (1967 to August 2018), and Web of Science (2002 to August 2018). We also searched reference lists, clinical trial registers (World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) to August 2018; ClinicalTrials.gov to August 2018), and conference proceedings, and we contacted study authors.

SELECTION CRITERIA

Randomised controlled trials comparing (1) pharmacological interventions with placebo; (2) one of various forms of non-invasive brain stimulation with sham stimulation or usual care; (3) one of various forms of psychological therapy with usual care and/or attention control; (4) pharmacological intervention and various forms of psychological therapy with pharmacological intervention and usual care and/or attention control; (5) non-invasive brain stimulation and pharmacological intervention with pharmacological intervention and sham stimulation or usual care; (6) pharmacological intervention and one of various forms of psychological therapy with placebo and psychological therapy; (7) pharmacological intervention and non-invasive brain stimulation with placebo plus non-invasive brain stimulation; (8) non-invasive brain stimulation and one of various forms of psychological therapy versus non-invasive brain stimulation plus usual care and/or attention control; and (9) non-invasive brain stimulation and one of various forms of psychological therapy versus sham brain stimulation or usual care plus psychological therapy, with the intention of treating depression after stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, assessed risk of bias, and extracted data from all included studies. We calculated mean difference (MD) or standardised mean difference (SMD) for continuous data, and risk ratio (RR) for dichotomous data, with 95% confidence intervals (CIs). We assessed heterogeneity using the I² statistic and certainty of the evidence according to GRADE.

MAIN RESULTS

We included 49 trials (56 comparisons) with 3342 participants. Data were available for: (1) pharmacological interventions with placebo (with 20 pharmacological comparisons); (2) one of various forms of non-invasive brain stimulation with sham stimulation or usual care (with eight non-invasive brain stimulation comparisons); (3) one of various forms of psychological therapy with usual care and/or attention control (with 16 psychological therapy comparisons); (4) pharmacological intervention and various forms of psychological therapy with pharmacological intervention and usual care and/or attention control (with two comparisons); and (5) non-invasive brain stimulation and pharmacological intervention with pharmacological intervention and sham stimulation or usual care (with 10 comparisons). We found no trials for the following comparisons: (6) pharmacological intervention and various forms of psychological therapy interventions versus placebo and psychological therapy; (7) pharmacological intervention and non-invasive brain stimulation versus placebo plus non-invasive brain stimulation; (8) non-invasive brain stimulation and one of various forms of psychological therapy versus non-invasive brain stimulation plus usual care and/or attention control; and (9) non-invasive brain stimulation and one of various forms of psychological therapy versus sham brain stimulation or usual care plus psychological therapy. Treatment effects observed: very low-certainty evidence from eight trials suggests that pharmacological interventions decreased the number of people meeting study criteria for depression (RR 0.70, 95% CI 0.55 to 0.88; 1025 participants) at end of treatment, and very low-certainty evidence from six trials suggests that pharmacological interventions decreased the number of people with less than 50% reduction in depression scale scores at end of treatment (RR 0.47, 95% CI 0.32 to 0.69; 511 participants) compared to placebo. No trials of non-invasive brain stimulation reported on meeting study criteria for depression at end of treatment. Only one trial of non-invasive brain stimulation reported on the outcome <50% reduction in depression scale scores; thus, we were unable to perform a meta-analysis for this outcome. Very low-certainty evidence from six trials suggests that psychological therapy decreased the number of people meeting the study criteria for depression at end of treatment (RR 0.77, 95% CI 0.62 to 0.95; 521 participants) compared to usual care/attention control. No trials of combination therapies reported on the number of people meeting the study criteria for depression at end of treatment. Only one trial of combination (non-invasive brain stimulation and pharmacological intervention) therapy reported <50% reduction in depression scale scores at end of treatment. Thus, we were unable to perform a meta-analysis for this outcome. Five trials reported adverse events related to the central nervous system (CNS) and noted significant harm in the pharmacological interventions group (RR 1.55, 95% CI 1.12 to 2.15; 488 participants; very low-certainty evidence). Four trials found significant gastrointestinal adverse events in the pharmacological interventions group (RR 1.62, 95% CI 1.19 to 2.19; 473 participants; very low-certainty evidence) compared to the placebo group. No significant deaths or adverse events were found in the psychological therapy group compared to the usual care/attention control group. Non-invasive brain stimulation interventions and combination therapies resulted in no deaths.

AUTHORS' CONCLUSIONS

Very low-certainty evidence suggests that pharmacological or psychological therapies can reduce the prevalence of depression. This very low-certainty evidence suggests that pharmacological therapy, psychological therapy, non-invasive brain stimulation, and combined interventions can reduce depressive symptoms. Pharmacological intervention was associated with adverse events related to the CNS and the gastrointestinal tract. More research is required before recommendations can be made about the routine use of such treatments.

Canadian Stroke Best Practice Recommendations: Rehabilitation, Recovery, and Community Participation following Stroke. Part One: Rehabilitation and Recovery Following Stroke; 6th Edition Update 2019

The sixth update of the Canadian Stroke Best Practice Recommendations: Rehabilitation, Recovery, and Reintegration following Stroke. Part one: Rehabilitation and Recovery Following Stroke is a comprehensive set of evidence-based guidelines addressing issues surrounding impairments, activity limitations, and participation restrictions following stroke. Rehabilitation is a critical component of recovery, essential for helping patients to regain lost skills, relearn tasks, and regain independence. Following a stroke, many people typically require rehabilitation for persisting deficits related to hemiparesis, upper-limb dysfunction, pain, impaired balance, swallowing, and vision, neglect, and limitations with mobility, activities of daily living, and communication. This module addresses interventions related to these issues as well as the structure in which they are provided, since rehabilitation can be provided on an inpatient, outpatient, or community basis. These guidelines also recognize that rehabilitation needs of people with stroke may change over time and therefore intermittent reassessment is important. Recommendations are appropriate for use by all healthcare providers and system planners who organize and provide care to patients following stroke across a broad range of settings. Unlike the previous set of recommendations, in which pediatric stroke was included, this set of recommendations includes primarily adult rehabilitation, recognizing many of these therapies may be applicable in children. Recommendations related to community reintegration, which were previously included within this rehabilitation module, can now be found in the companion module, Rehabilitation, Recovery, and Community Participation following Stroke. Part Two: Transitions and Community Participation Following Stroke.

A new central post-stroke pain rat model: autologous blood injected thalamic hemorrhage involved increased expression of P2X4 receptor

Stroke is the leading cause of disability and death in the world. Central post-stroke pain (CPSP), a central neuropathic pain syndrome occurring after cerebral stroke, is a serious problem. But on account of the lack of reliable animal models, the mechanisms underlying CPSP remains poorly understood. To better understand of the pathophysiological basis of CPSP, we developed and characterized a new rat model of CPSP. This model is based on a hemorrhagic stroke lesion with intra-thalamic autologous blood (ITAB) injection in the ventral posterolateral nucleus of the thalamus. Behavioral analysis demonstrated that the animals displayed a significant decrease in mechanical allodynia threshold. We found a significant increase in P2 × 4 receptor expression in microglia in thalamic peri-lesion tissues post-hemorrhage. The mechanical allodynia in rats with CPSP were reversed by blocking P2 × 4 receptors. A significant alleviation of mechanical allodynia was achieved following the administration of adrenergic antidepressants and antiepileptics. Meanwhile, we found a significant decrease in P2 × 4 receptor expression after treatment with these drugs. Taken together, our results suggest that targeting P2 × 4 receptor may be effective in the treatment of CPSP.

Long-Term Outcomes in the Management of Central Neuropathic Pain Syndromes: A Prospective Observational Cohort Study

Background:Central neuropathic pain syndromes are a result of central nervous system injury, most commonly related to stroke, traumatic spinal cord injury, or multiple sclerosis. These syndromes are distinctly less common than peripheral neuropathic pain, and less is known regarding the underlying pathophysiology, appropriate pharmacotherapy, and long-term outcomes. The objective of this study was to determine the long-term clinical effectiveness of the management of central neuropathic pain relative to peripheral neuropathic pain at tertiary pain centers.Methods:Patients diagnosed with central (n=79) and peripheral (n=710) neuropathic pain were identified for analysis from a prospective observational cohort study of patients with chronic neuropathic pain recruited from seven Canadian tertiary pain centers. Data regarding patient characteristics, analgesic use, and patient-reported outcomes were collected at baseline and 12-month follow-up. The primary outcome measure was the composite of a reduction in average pain intensity and pain interference. Secondary outcome measures included assessments of function, mood, quality of life, catastrophizing, and patient satisfaction.Results:At 12-month follow-up, 13.5% (95% confidence interval [CI], 5.6-25.8) of patients with central neuropathic pain and complete data sets (n=52) achieved a ≥30% reduction in pain, whereas 38.5% (95% CI, 25.3-53.0) achieved a reduction of at least 1 point on the Pain Interference Scale. The proportion of patients with central neuropathic pain achieving both these measures, and thus the primary outcome, was 9.6% (95% CI, 3.2-21.0). Patients with peripheral neuropathic pain and complete data sets (n=463) were more likely to achieve this primary outcome at 12 months (25.3% of patients; 95% CI, 21.4-29.5) (p=0.012).Conclusion:Patients with central neuropathic pain syndromes managed in tertiary care centers were less likely to achieve a meaningful improvement in pain and function compared with patients with peripheral neuropathic pain at 12-month follow-up.

Alleviation of thalamic pain by cilostazol administration: a case report

Thalamic pain is severe and treatment-resistant; however, there are few available options for improving thalamic pain. This study demonstrated that thalamic pain was alleviated by administration of cilostazol, suggesting that cilostazol may be a candidate for treating thalamic pain.

Deep Brain Stimulation for the Treatment of Dejerine-Roussy Syndrome

BACKGROUND/AIMS

Patients who suffer from Dejerine-Roussy syndrome commonly experience severe poststroke hemibody pain which has historically been attributed to thalamic lesions. Despite pharmacological treatment, a significant proportion of the population is resistant to traditional therapy. Deep brain stimulation is often appropriate for the treatment of resistant populations. In this review we aim to summarize the targets that are used to treat Dejerine-Roussy syndrome and provide insight into their clinical efficacy.

METHODS

In reviewing the literature, we defined stimulation success as achievement of a minimum of 50% pain relief.

RESULTS

Contemporary targets for deep brain stimulation are the ventral posterior medial/ventral posterior lateral thalamic nuclei, periaqueductal/periventricular gray matter, the ventral striatum/anterior limb of the internal capsule, left centromedian thalamic nuclei, the nucleus ventrocaudalis parvocellularis internis, and the posterior limb of the internal capsule.

CONCLUSIONS

Due to technological advancements in deep brain stimulation, its therapeutic effects must be reevaluated. Despite a lack of controlled evidence, deep brain stimulation has been effectively used as a therapeutic in clinical pain management. Further clinical investigation is needed to definitively evaluate the therapeutic efficacy of deep brain stimulation in treating the drug-resistant patient population.

Central poststroke pain: A systematic review

Background Physical, psychological, and/or social impairment can result after a stroke and can be exacerbated by pain. One type of pain after stroke, central poststroke pain, is believed to be due to primary central nervous system mechanisms. Estimated prevalence of central poststroke pain ranges widely from 8% to 55% of stroke patients, suggesting a difficulty in reliably, accurately, and consistently identifying central poststroke pain. This may be due to the absence of a generally accepted definition. Aim We aimed to clarify the role of thalamic strokes and damage to the spinothalamic pathway in central poststroke pain patients. Also, we aimed to gain a current understanding of anatomic substrates, brain imaging, and treatment of central poststroke pain. Summary of review Two independent reviewers identified 10,144 publications. Based on Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines, we extracted data from 23 papers and categorized the articles' aims into four sections: somatosensory deficits, pathway stimulation, clinical trials, and brain imaging. Conclusions Our systematic review suggests that damage to the spinothalamic pathway is associated with central poststroke pain and this link could provide insights into mechanisms and treatment. Moreover, historical connection of strokes in the thalamic region of the brain and central poststroke pain should be reevaluated as many studies noted that strokes in other regions of the brain have high occurrence of central poststroke pain as well.

Demystifying Poststroke Pain: From Etiology to Treatment

Pain after stroke is commonly reported but often incompletely managed, which prevents optimal recovery. This situation occurs in part because of the esoteric nature of poststroke pain and its limited presence in current discussions of stroke management. The major specific afflictions that affect patients with stroke who experience pain include central poststroke pain, complex regional pain syndrome, and pain associated with spasticity and shoulder subluxation. Each disorder carries its own intricacies that require specific approaches to treatment and understanding. This review aims to present and clarify the major pain syndromes that affect patients who have experienced a stroke in order to aid in their diagnosis and treatment.

Antidepressants in the Treatment of Chronic Pain

Antidepressants have been successfully used for chronic pain syndromes for approximately 30 years. One theory is that analgesic action is secondary to the antidepressant effects of the medications. Placebo-controlled trials have documented that antidepressants treat neuropathic pain, musculoskeletal pain, chronic pain, and cancer pain. The most frequently studied antidepressant for pain is amitriptyline. Other antidepressants that have shown analgesic activity include imipramine, citalopram, paroxetine, nortriptyline, desipramine, and mianserin. Fluoxetine and trazodone have not been shown to successfully treat pain syndromes. Venlafaxine, a new antidepressant, most recently was shown to have antidepressant activity in fibromyalgia. More studies need to be done with newer antidepressants to confirm their place in treating pain syndromes.

Guidelines for Adult Stroke Rehabilitation and Recovery: A Guideline for Healthcare Professionals From the American Heart Association/American Stroke Association

PURPOSE

The aim of this guideline is to provide a synopsis of best clinical practices in the rehabilitative care of adults recovering from stroke.

METHODS

Writing group members were nominated by the committee chair on the basis of their previous work in relevant topic areas and were approved by the American Heart Association (AHA) Stroke Council's Scientific Statement Oversight Committee and the AHA's Manuscript Oversight Committee. The panel reviewed relevant articles on adults using computerized searches of the medical literature through 2014. The evidence is organized within the context of the AHA framework and is classified according to the joint AHA/American College of Cardiology and supplementary AHA methods of classifying the level of certainty and the class and level of evidence. The document underwent extensive AHA internal and external peer review, Stroke Council Leadership review, and Scientific Statements Oversight Committee review before consideration and approval by the AHA Science Advisory and Coordinating Committee.

RESULTS

Stroke rehabilitation requires a sustained and coordinated effort from a large team, including the patient and his or her goals, family and friends, other caregivers (eg, personal care attendants), physicians, nurses, physical and occupational therapists, speech-language pathologists, recreation therapists, psychologists, nutritionists, social workers, and others. Communication and coordination among these team members are paramount in maximizing the effectiveness and efficiency of rehabilitation and underlie this entire guideline. Without communication and coordination, isolated efforts to rehabilitate the stroke survivor are unlikely to achieve their full potential.

CONCLUSIONS

As systems of care evolve in response to healthcare reform efforts, postacute care and rehabilitation are often considered a costly area of care to be trimmed but without recognition of their clinical impact and ability to reduce the risk of downstream medical morbidity resulting from immobility, depression, loss of autonomy, and reduced functional independence. The provision of comprehensive rehabilitation programs with adequate resources, dose, and duration is an essential aspect of stroke care and should be a priority in these redesign efforts. (Stroke.2016;47:e98-e169. DOI: 10.1161/STR.0000000000000098.).

Brain Stimulation Therapy for Central Post-Stroke Pain from a Perspective of Interhemispheric Neural Network Remodeling

Central post-stroke pain (CPSP) is a debilitating, severe disorder affecting patient quality of life. Since CPSP is refractory to medication, various treatment modalities have been tried with marginal results. Following the first report of epidural motor cortex (M1) stimulation (MCS) for CPSP, many researchers have investigated the mechanisms of electrical stimulation of the M1. CPSP is currently considered to be a maladapted network reorganization problem following stroke, and recent studies have revealed that the activities of the impaired hemisphere after stroke may be inhibited by the contralesional hemisphere. Even though this interhemispheric inhibition (IHI) theory was originally proposed to explain the motor recovery process in stroke patients, we considered that IHI may also contribute to the CPSP mechanism. Based on the IHI theory and the fact that electrical stimulation of the M1 suppresses CPSP, we hypothesized that the inhibitory signals from the contralesional hemisphere may suppress the activities of the M1 in the ipsilesional hemisphere, and therefore pain suppression mechanisms may be malfunctioning in CPSP patients. In this context, transcranial direct current stimulation (tDCS) was considered to be a reasonable procedure to address the interhemispheric imbalance, as the bilateral M1 can be simultaneously stimulated using an anode (excitatory) and cathode (inhibitory). In this article, we review the potential mechanisms and propose a new model of CPSP. We also report two cases where CPSP was addressed with tDCS, discuss the potential roles of tDCS in the treatment of CPSP, and make recommendations for future studies.

Central Neuropathic Pain Syndromes

Chronic pain is common in patients with neurologic complications of a central nervous system insult such as stroke. The pain is most commonly musculoskeletal or related to obligatory overuse of neurologically unaffected limbs. However, neuropathic pain can result directly from the central nervous system injury. Impaired sensory discrimination can make it challenging to differentiate central neuropathic pain from other pain types or spasticity. Central neuropathic pain may also begin months to years after the injury, further obscuring recognition of its association with a past neurologic injury. This review focuses on unique clinical features that help distinguish central neuropathic pain. The most common clinical central pain syndromes-central poststroke pain, multiple sclerosis-related pain, and spinal cord injury-related pain-are reviewed in detail. Recent progress in understanding of the pathogenesis of central neuropathic pain is reviewed, and pharmacological, surgical, and neuromodulatory treatments of this notoriously difficult to treat pain syndrome are discussed.

[Spinal cord stimulation for thalamic pain: Case report and review of the current literature]

BACKGROUND

Spinal cord stimulation (SCS) is an established procedure for treatment of chronic neuropathic pain of peripheral origin. The efficacy of SCS in case of central poststroke pain (CPSP), especially thalamic pain, has not been adequately proven.

OBJECTIVES

The efficacy of SCS as an extracranial neurostimulation method for the management of central pain syndrome was investigated.

MATERIALS AND METHODS

In this study, relevant pharmacological and nonpharmacological measures for central pain management were reviewed. A case of successful SCS for thalamic pain after ischemic insult is presented. Explanatory approaches of pathophysiological processes and a review of the current literature underline our results.

RESULTS

In the case presented, SCS was found effective in the treatment of thalamic pain.

CONCLUSION

The efficacy of SCS might be caused by segmental and supraspinal processes and collaboration of activating and inhibiting pathways. The integrity of the spinothalamic tract is mandatory. SCS is a treatment option for central pain syndrome, especially thalamic pain. Comparable studies confirm the potency of this technique. In contrast to other neuromodulation procedures spinal cord stimulation is less invasive, has a lower perioperative risk and is often less expensive. Further studies are needed to define its potential and role in the treatment of thalamic pain.

Management of Central Poststroke Pain

Background and Purpose—

Central poststroke pain is a chronic neuropathic disorder that follows a stroke. Current research on its management is limited, and no review has evaluated all therapies for central poststroke pain.

Methods—

We conducted a systematic review of randomized controlled trials to evaluate therapies for central poststroke pain. We identified eligible trials, in any language, by systematic searches of AMED, CENTRAL, CINAHL, DARE, EMBASE, HealthSTAR, MEDLINE, and PsychINFO. Eligible trials (1) enrolled ≥10 patients with central poststroke pain; (2) randomly assigned them to an active therapy or a control arm; and (3) collected outcome data ≥14 days after treatment. Pairs of reviewers, independently and in duplicate, screened titles and abstracts of identified citations, reviewed full texts of potentially eligible trials, and extracted information from eligible studies. We used a modified Cochrane tool to evaluate risk of bias of eligible studies, and collected patient-important outcomes according to recommendations by the Initiative on Methods, Measurement, and Pain Assessment in Clinical Trials. We conducted, when possible, random effects meta-analyses, and evaluated our certainty in treatment effects using the Grading of Recommendations Assessment, Development, and Evaluation System.

Results—

Eight eligible English language randomized controlled trials (459 patients) tested anticonvulsants, an antidepressant, an opioid antagonist, repetitive transcranial magnetic stimulation, and acupuncture. Results suggested that all therapies had little to no effect on pain and other patient-important outcomes. Our certainty in the treatment estimates ranged from very low to low.

Conclusions—

Our findings are inconsistent with major clinical practice guidelines; the available evidence suggests no beneficial effects of any therapies that researchers have evaluated in randomized controlled trials.

Amitriptyline for neuropathic pain in adults

BACKGROUND

This is an updated version of the original Cochrane review published in Issue 12, 2012. That review considered both fibromyalgia and neuropathic pain, but the effects of amitriptyline for fibromyalgia are now dealt with in a separate review.Amitriptyline is a tricyclic antidepressant that is widely used to treat chronic neuropathic pain (pain due to nerve damage). It is recommended as a first line treatment in many guidelines. Neuropathic pain can be treated with antidepressant drugs in doses below those at which the drugs act as antidepressants.

OBJECTIVES

To assess the analgesic efficacy of amitriptyline for relief of chronic neuropathic pain, and the adverse events associated with its use in clinical trials.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and EMBASE to March 2015, together with two clinical trial registries, and the reference lists of retrieved papers, previous systematic reviews, and other reviews; we also used our own hand searched database for older studies.

SELECTION CRITERIA

We included randomised, double-blind studies of at least four weeks' duration comparing amitriptyline with placebo or another active treatment in chronic neuropathic pain conditions.

DATA COLLECTION AND ANALYSIS

We performed analysis using three tiers of evidence. First tier evidence derived from data meeting current best standards and subject to minimal risk of bias (outcome equivalent to substantial pain intensity reduction, intention-to-treat analysis without imputation for dropouts; at least 200 participants in the comparison, 8 to 12 weeks' duration, parallel design), second tier from data that failed to meet one or more of these criteria and were considered at some risk of bias but with adequate numbers in the comparison, and third tier from data involving small numbers of participants that were considered very likely to be biased or used outcomes of limited clinical utility, or both.

MAIN RESULTS

We included 15 studies from the earlier review and two new studies (17 studies, 1342 participants) in seven neuropathic pain conditions. Eight cross-over studies with 302 participants had a median of 36 participants, and nine parallel group studies with 1040 participants had a median of 84 participants. Study quality was modest, though most studies were at high risk of bias due to small size.There was no first-tier or second-tier evidence for amitriptyline in treating any neuropathic pain condition. Only third-tier evidence was available. For only two of seven studies reporting useful efficacy data was amitriptyline significantly better than placebo (very low quality evidence).More participants experienced at least one adverse event; 55% of participants taking amitriptyline and 36% taking placebo. The risk ratio (RR) was 1.5 (95% confidence interval (CI) 1.3 to 1.8) and the number needed to treat for an additional harmful outcome was 5.2 (3.6 to 9.1) (low quality evidence). Serious adverse events were rare. Adverse event and all-cause withdrawals were not different, but were rarely reported (very low quality evidence).

AUTHORS' CONCLUSIONS

Amitriptyline has been a first-line treatment for neuropathic pain for many years. The fact that there is no supportive unbiased evidence for a beneficial effect is disappointing, but has to be balanced against decades of successful treatment in many people with neuropathic pain. There is no good evidence of a lack of effect; rather our concern should be of overestimation of treatment effect. Amitriptyline should continue to be used as part of the treatment of neuropathic pain, but only a minority of people will achieve satisfactory pain relief. Limited information suggests that failure with one antidepressant does not mean failure with all.

A Comprehensive Review of Central Post-Stroke Pain

Although central post-stroke pain is widely recognized as a severe chronic neuropathic pain condition, its consolidated definition, clinical characteristics, and diagnostic criteria have not been defined due to its clinically diverse features. The present study was undertaken to comprehensively review current literature and provide a more complete picture of central post-stroke pain with respect to its definition, prevalence, pathophysiology, clinical characteristics, and diagnostic problems, and to describe the range of therapies currently available. In particular, nursing care perspectives are addressed. It is hoped that this review will help nurses become knowledgeable about central post-stroke pain and provide valuable information for the drafting of effective nursing care plans that improve outcomes and quality of life for patients with central post-stroke pain.

Neuropathic pain: principles of diagnosis and treatment

Neuropathic pain is caused by disease or injury of the nervous system and includes various chronic conditions that, together, affect up to 8% of the population. A substantial body of neuropathic pain research points to several important contributory mechanisms including aberrant ectopic activity in nociceptive nerves, peripheral and central sensitization, impaired inhibitory modulation, and pathological activation of microglia. Clinical evaluation of neuropathic pain requires a thorough history and physical examination to identify characteristic signs and symptoms. In many cases, other laboratory investigations and clinical neurophysiological testing may help identify the underlying etiology and guide treatment selection. Available treatments essentially provide only symptomatic relief and may include nonpharmacological, pharmacological, and interventional therapies. Most extensive evidence is available for pharmacological treatment, and currently recommended first-line treatments include antidepressants (tricyclic agents and serotonin-norepinephrine reuptake inhibitors) and anticonvulsants (gabapentin and pregabalin). Individualized multidisciplinary patient care is facilitated by careful consideration of pain-related disability (eg, depression and occupational dysfunction) as well as patient education; repeat follow-up and strategic referral to appropriate medical/surgical subspecialties; and physical and psychological therapies. In the near future, continued preclinical and clinical research and development are expected to lead to further advancements in the diagnosis and treatment of neuropathic pain.

Pharmacogenetics and analgesic effects of antidepressants in chronic pain management

Antidepressants are widely administered to chronic pain patients, but there is large interindividual variability in their efficacy and adverse effect rates that may be attributed to genetic factors. Studies have attempted to determine the impact of genetic polymorphisms in enzymes and transporters that are involved in antidepressant pharmacokinetics, for example, cytochrome P450 and P-gp. The impacts of genetic polymorphisms in the targets of antidepressants, such as the serotonin receptor or transporter, the noradrenaline transporter and the COMT and monoamine oxydase enzymes, have also been described. This manuscript discusses the current knowledge of the influence of genetic factors on the plasma concentrations, efficacy and adverse effects of the major antidepressants used in pain management.