Neuropathic pain characteristics in patients from Curitiba (Brazil) with spinal cord injury

Occurrence of neuropathic pain and its characteristics in patients with traumatic spinal cord injury

Objectives: Assess the occurrence of neuropathic pain in spinal cord injured persons (SCIP) and define the relationship between neuropathic pain with demographic and clinical characteristics in SCIPs.Methods: This Analytical cross-sectional study was conducted on 104 SCIPs treated at our tertiary care hospital. Initial clinical evaluation was done according to the American Spinal Injury Association (ASIA) impairment scale. A clinical evaluation was done. All subjects were screened with the Leeds Assessment of Neuropathic Symptoms, Signs (LANSS) and DN4 questionnaire for neuropathic pain. The Visual Analogue Scale (VAS) was used to measure the severity of neuropathic pain. Later two groups were created based on the presence and absence of neuropathic pain.Results: The mean age was 35.04 ± 13 years. Fifty-eight patients (55.8%) had a complete injury (ASIA grade A), 41 (39.4%) patients had an incomplete kind of injury (ASIA grade B-D) and 5(4.8%) patients had no deficits (ASIA grade E). Neuropathic pain was present in 77(74.0%) and absent in 27(26.0%) patients. Seventy-one patients (92.2%) experience neuropathic pain in the first year after traumatic SCI. Medicines were a common pain-relieving factor 64(83.1%).Conclusion: 74% of patients complained of neuropathic pain, indicating a significant complication. A comprehensive evaluation and treatment are necessary to address it while including variables like the completeness of injury, duration and timing.

Relationships between cardiovascular disease risk, neuropathic pain, mental health, and autonomic function in chronic spinal cord injury

STUDY DESIGN

Multicentre, cross-sectional study.

OBJECTIVES

To determine if clinical measures of poor mental health (MH-) and neuropathic pain (NP) are related to increased CVD risk in individuals with chronic spinal cord injury (SCI), and further elucidate the relationships between CVD risk, autonomic function, NP, and MH-.

SETTING

Eight SCI rehabilitation centres in the Netherlands.

METHODS

Individuals (n = 257) with a traumatic, chronic (≥10 yrs) SCI, with age at injury between 18-35 years, completed a self-report questionnaire and a one-day visit to a rehabilitation centre for testing. CVD risk was calculated using Framingham risk score. NP was inferred using The Douleur Neuropathique 4 clinical examination, and MH- was assessed using the five-item Mental Health Inventory questionnaire. Cardiovascular autonomic function was determined from peak heart rate during maximal exercise (HRpeak).

RESULTS

There was a high prevalence of both NP (39%) and MH- (45%) following SCI. MH- was significantly correlated with an adverse CVD risk profile (r = 0.174; p = 0.01), increased the odds of adverse 30-year CVD risk by 2.2 (CI 0.92-2.81, p = 0.02), and is an important variable in determining CVD risk (importance=0.74, p = 0.05). Females (p = 0.05) and those with a higher HRpeak (p = 0.046) tended to be more likely to have NP.

CONCLUSIONS

Clinical measures of MH-, but not NP, are important factors for increased CVD risk following SCI. NP tended to be more prevalent in those with more preserved cardiovascular autonomic function. The interrelationships between secondary consequences of SCI are complex and need further exploration.

Is transcranial magnetic stimulation as treatment for neuropathic pain in patients with spinal cord injury efficient? A systematic review

BACKGROUND AND PURPOSE

Neuropathic pain is a clinically relevant complication in individuals with spinal cord injury (SCI). Pharmacological pain treatment is often insufficient and leads to undesirable side effects. Thus, alternative therapeutic approaches such as repetitive transcranial magnetic stimulation (rTMS) are of critical importance. We aimed to evaluate the effectiveness of rTMS in neuropathic pain secondary to SCI.

METHODS

We conducted a systematic review using the PubMed/MEDLINE, EMBASE, and PsycInfo (via OVID) database up April 2021. Only randomized controlled trials were included. Results regarding the pain intensity scores were pooled using a random-effects model.

RESULTS

The search identified a total of 203 potential articles. Of these, eight randomized controlled trials (RCTs) met the eligibility criteria for qualitative synthesis providing the total data of 141 patients. All studies applied high-frequency rTMS. In seven studies, rTMS was applied over the motor cortex, and in one study over the left dorsolateral prefrontal cortex. Five studies reported a significant improvement in baseline pain scores after treatment, and three studies found a significant difference between sham vs. non-sham stimulation at any time. Six RCTs were included in the quantitative synthesis and showed a significant overall reduction of pain intensity in the rTMS groups compared with the sham groups (mean difference - 0.81, 95%CI - 1.45 to - 0.17).

CONCLUSIONS

Our findings indicate that high-frequency rTMS of the primary motor cortex and left dorsolateral prefrontal cortex might be promising stimulation targets for neuropathic pain in SCI.

Prevalence and Characteristics of Neuropathic Pain in Patients With Spinal Cord Injury Referred to a Rehabilitation Center

OBJECTIVE

To identify the prevalence and characteristics of neuropathic pain (NP) in patients with spinal cord injury (SCI) and to investigate associations between NP and demographic or disease-related variables.

METHODS

We retrospectively reviewed medical records of patients with SCI whose pain was classified according to the International Spinal Cord Injury Pain classifications at a single hospital. Multiple statistical analyses were employed. Patients aged <19 years, and patients with other neurological disorders and congenital conditions were excluded.

RESULTS

Of 366 patients, 253 patients (69.1%) with SCI had NP. Patients who were married or had traumatic injury or depressive mood had a higher prevalence rate. When other variables were controlled, marital status and depressive mood were found to be predictors of NP. There was no association between the prevalence of NP and other demographic or clinical variables. The mean Numeric Rating Scale (NRS) of NP was 4.52, and patients mainly described pain as tingling, squeezing, and painful cold. Females and those with below-level NP reported more intense pain. An NRS cut-off value of 4.5 was determined as the most appropriate value to discriminate between patients taking pain medication and those who did not.

CONCLUSION

In total, 69.1% of patients with SCI complained of NP, indicating that NP was a major complication. Treatment planning for patients with SCI and NP should consider that marital status, mood, sex, and pain subtype may affect NP, which should be actively managed in patients with an NRS ≥4.5.

Function and Mechanisms of Truncated BDNF Receptor TrkB.T1 in Neuropathic Pain

Brain-derived neurotrophic factor (BDNF), a major focus for regenerative therapeutics, has been lauded for its pro-survival characteristics and involvement in both development and recovery of function within the central nervous system (CNS). However, studies of tyrosine receptor kinase B (TrkB), a major receptor for BDNF, indicate that certain effects of the TrkB receptor in response to disease or injury may be maladaptive. More specifically, imbalance among TrkB receptor isoforms appears to contribute to aberrant signaling and hyperpathic pain. A truncated isoform of the receptor, TrkB.T1, lacks the intracellular kinase domain of the full length receptor and is up-regulated in multiple CNS injury models. Such up-regulation is associated with hyperpathic pain, and TrkB.T1 inhibition reduces neuropathic pain in various experimental paradigms. Deletion of TrkB.T1 also limits astrocyte changes in vitro, including proliferation, migration, and activation. Mechanistically, TrkB.T1 is believed to act through release of intracellular calcium in astrocytes, as well as through interactions with neurotrophins, leading to cell cycle activation. Together, these studies support a potential role for astrocytic TrkB.T1 in hyperpathic pain and suggest that targeted strategies directed at this receptor may have therapeutic potential.

Evaluation of a Clinical Protocol to Assess and Diagnose Neuropathic Pain During Acute Hospital Admission: Results From Traumatic Spinal Cord Injury

OBJECTIVES

A clinical protocol was developed for clinicians to routinely assess and initiate treatment for patients with neuropathic pain (NP) in an acute care setting. The objectives of this study were to: (1) determine the incidence and onset of NP in patients with traumatic spinal cord injury during acute care and (2) describe how the implementation of a clinical protocol impacts the assessment and diagnosis of NP.

MATERIALS AND METHODS

The study was a cohort analysis with a pre-post-test utilizing a historical control. Data were retrospectively collected from a patient registry and charts. Participants were randomly selected in cohort 1 (control) and cohort 2 (NP clinical protocol).

RESULTS

The incidence of NP was 56% without significant difference between the cohorts (P=0.3). Onset of NP was 8 days (SD=14) across the study and >85% of the participants with NP were diagnosed within 2 weeks. Participants with incomplete injuries had a significant earlier onset than participants with complete injuries (6.2±12.8, 10.9±15.8 d; P=0.003). The mean number of days from hospital admission to initial assessment decreased with use of the NP clinical protocol (3.7±5.7 d; P=0.02).

DISCUSSION

This study demonstrates a high incidence and early onset of NP in traumatic spinal cord injury during acute hospital care, with an earlier emergence in participants with incomplete injury. The NP clinical protocol ensured continuous assessment and documentation of NP while decreasing the time to an initial screen, but did not impact diagnosis.

Frequency and age effects of secondary health conditions in individuals with spinal cord injury: a scoping review

STUDY DESIGN

Scoping review.

OBJECTIVES

To gain a better understanding of the prevalence, course and association with age of secondary health conditions in individuals with spinal cord injury (SCI).

SETTING

Seattle, Washington, USA.

METHODS

We performed searches of electronic databases for studies published from 1986-2011 that provided information regarding the prevalence, course or associations with age and duration of secondary health conditions in individuals with SCI.

RESULTS

Ninety-two studies were included. The findings indicate that: (1) individuals with SCI experience a number of secondary health conditions, many of which occur at a higher rate in those with SCI than the normative population; (2) the most common conditions or symptoms are pain, bowel and bladder regulation problems, muscle spasms, fatigue, esophageal symptom and osteoporosis; (3) a number of conditions, including cardiovascular disease, diabetes, bone mineral density loss, fatigue and respiratory complications or infections, occur with higher frequency in older individuals or those with longer SCI duration, relative to younger individuals or those with shorter SCI duration; and (4) there is a marked lack of longitudinal research examining the natural course of health conditions in individuals aging with SCI.

CONCLUSIONS

The findings support the conclusion that individuals with SCI show signs of 'premature aging' in different organ systems. Longitudinal research is needed to understand when problems are most likely to emerge, and to develop and test the efficacy of interventions to prevent these health conditions and their negative impact.

Neuropathic pain in patients with spinal cord injury: report of 213 patients

Objective Management of neuropathic pain following spinal cord injury (SCI) can be a frustrating experience for patients since it poses a therapeutic challenge. In this article the authors describe the clinical characteristics of a group of patients with pain after spinal cord injury. Methods In this retrospective study, 213 patients with SCI and neuropathic pain were assessed. We analyzed clinical characteristics, treatment options, and pain intensity for these patients. Results The main cause of SCI was spine trauma, which occurred in 169 patients, followed by tumors and infection. Complete lesions were verified in 144 patients. In our study, patients with traumatic SCI and partial lesions seem to be presented with more intense pain; however, this was not statistically significant. Conclusions Neuropathic pain is a common complaint in patients with SCI and presents a treatment challenge. Knowledge of the clinical characteristics of this group of patients may help determine the best approach to intervention.