Identification and Characterization of Unique Subgroups of Chronic Pain Individuals with Dispositional Personality Traits.

Objective. The current study attempted to identify and characterize distinct CP subgroups based on their level of dispositional personality traits. The secondary objective was to compare the difference among the subgroups in mood, coping, and disability. Methods. Individuals with chronic pain were assessed for demographic, psychosocial, and personality measures. A two-step cluster analysis was conducted in order to identify distinct subgroups of patients based on their level of personality traits. Differences in clinical outcomes were compared using the multivariate analysis of variance based on cluster membership. Results. In 229 participants, three clusters were formed. No significant difference was seen among the clusters on patient demographic factors including age, sex, relationship status, duration of pain, and pain intensity. Those with high levels of dispositional personality traits had greater levels of mood impairment compared to the other two groups (p < 0.05). Significant difference in disability was seen between the subgroups. Conclusions. The study identified a high risk group of CP individuals whose level of personality traits significantly correlated with impaired mood and coping. Use of pharmacological treatment alone may not be successful in improving clinical outcomes among these individuals. Instead, a more comprehensive treatment involving psychological treatments may be important in managing the personality traits that interfere with recovery.

The Long Term Role of Anxiety Sensitivity and Experiential Avoidance on Pain Intensity, Mood, and Disability among Individuals in a Specialist Pain Clinic.

Background. Anxiety sensitivity (AS) and experiential avoidance (EA) have been shown to have an interactive effect on the response an individual has to chronic pain (CP) potentially resulting in long term negative outcomes. Objective. The current study attempted to (1) identify distinct CP subgroups based on their level of EA and AS and (2) compare the subgroups in terms of mood and disability. Methods. Individuals with CP were recruited from an academic pain clinic. Individuals were assessed for demographic, psychosocial, and personality measures at baseline and 1-year follow-up. A cluster analysis was conducted to identify distinct subgroups of patients based on their level of EA and AS. Differences in clinical outcomes were compared using the Repeated Measures MANOVA. Results. From a total of 229 participants, five clusters were formed. Subgroups with lower levels of AS but similar high levels of EA did not differ in outcomes. Mood impairment was significantly greater among those with high levels of EA compared to lower levels (p < 0.05). Significant improvement in disability (p < 0.05) was only seen among those with lower levels of EA and AS. Conclusions. This cluster analysis demonstrated that EA had a greater influence on mood impairment, while both EA and AS levels affected disability outcomes among individuals with CP.

Mood, Disability, and Quality of Life among a Subgroup of Rheumatoid Arthritis Individuals with Experiential Avoidance and Anxiety Sensitivity.

Objective. The current study aimed to identify and characterize distinct RA subgroups based on their level of EA and AS and compares the difference among the subgroups in mood, disability, and quality of life. Methods. Individuals with chronic pain for at least 3 months were recruited from an academic rheumatoid clinic. Participants were assessed for demographic, psychosocial, and personality measures. A two-step cluster analysis was conducted to identify distinct subgroups of patients. Differences in clinical outcomes were compared using the Multivariate ANOVA based on cluster membership. Results. From a total of 223 participants, three distinct subgroups were formed based on cluster analysis. Cluster 1 (N = 78) included those with low levels of both EA and AS. Cluster 2 (N = 81) consisted of individuals with moderate levels of EA and low levels AS. Cluster 3 (N = 64) included those with moderate levels of EA and high AS. Compared to those in Cluster 1, those in Cluster 3 had significantly higher levels of mood impairment and disability and lower quality of life (p < 0.05). Significantly lower levels of mood impairment were seen in Cluster 1 compared to Cluster 2 (p < 0.05). However, no significant difference in disability or quality of life was seen between the two groups. Conclusions. The three subgroups differed significantly in levels of impairment in mood, disability, and quality of life. However, levels of EA had a greater impact on disability and quality of life than AS.

Effectiveness of transcranial direct current stimulation for the management of neuropathic pain after spinal cord injury: a meta-analysis.

OBJECTIVES: To conduct a systematic review and meta-analysis to examine the effect of transcranial direct current stimulation (tDCS) on reducing neuropathic pain intensity in individuals with spinal cord injury (SCI). METHODS: Medline, CINAHL, EMBASE and PsycINFO databases were searched for all relevant articles published from 1980 to November 2014. Trials were included if (i) tDCS intervention group and a placebo control group were present; (ii) at least 50% of participants in the study had an SCI and there were at least three participants; (iii) participants were aged 18 years or older; and (iv) persistent pain for at least 3 months. Studies were excluded if: (i) the tDCS intervention group was compared with an active treatment group; (ii) there was insufficient reporting detail to enable pooling of data; and (iii) it was a nonclinical trial (that is, reviews, epidemiology, basic sciences). A standardized mean difference (SMD) ± s.e. and 95% confidence interval (CI) was calculated for each outcome of interest and the results were pooled using a fixed or random effects model, as appropriate. Effect sizes were interpreted as: small > 0.2, moderate > 0.5, large > 0.8. RESULTS: Five studies met inclusion criteria of which four were randomized controlled trials and one was a prospective controlled trial. The pooled analysis found a significant effect of tDCS on reducing neuropathic pain after SCI post treatment (SMD = 0.510 ± 0.202; 95% CI, 0.114-0.906; P < 0.012); however, this effect was not maintained at follow-up (SMD = 0.353 ± 0.272; 95% CI, -0.179 to 0.886; P < 0.194). A reduction of 1.33 units on a 10-item scale was observed post treatment. No significant adverse events were reported. CONCLUSION: Meta-analytic results indicate a moderate effect of tDCS in reducing neuropathic pain among individuals with SCI; however, the effect was not maintained at follow-up. A mean pooled decrease of 1.33 units on a 10-item scale was found post treatment. Several factors were implicated in the effectiveness of tDCS in reducing pain. Due to the limited number of studies and lack of follow-up, more evidence is required before treatment recommendations can be made.

A systematic review of the therapeutic interventions for heterotopic ossification after spinal cord injury.

STUDY DESIGN: Systematic review. OBJECTIVE: To conduct a systematic review of the effectiveness of interventions used to prevent and treat heterotopic ossification (HO) after spinal cord injury (SCI). SETTING: St Joseph's Parkwood Hospital, London, Ontario, Canada. METHODS: MEDLINE, CINAHL, EMBASE and PsycINFO databases were searched for articles addressing the treatment of HO after SCI. Studies were selected by two reviewers and were only included for analysis if at least 50% of the subjects had an SCI, there were at least three SCI subjects and if the study subjects participated in a treatment or intervention. Study quality was assessed by two independent reviewers using the Downs and Black evaluation tool for all studies, as well as the PEDro assessment scale for randomized control trials only. Levels of evidence were assigned using a modified Sackett scale. RESULTS: A total of 13 studies met the inclusion criteria. The selected articles were divided into prevention or treatment of post-SCI HO. Nonsteroidal anti-inflammatory drugs (NSAIDs), warfarin, and pulse low-intensity electrogmagnetic field (PLIMF) therapy were reviewed as prophylactic measures. Bisphosphonates, radiotherapy and excision were reviewed as treatments of post-SCI HO. CONCLUSIONS: Pharmacological treatments of HO after SCI had the highest level of research evidence supporting their use. Of these, NSAIDs showed greatest efficacy in the prevention of HO when administered early after an SCI, whereas bisphosphonates were the intervention with strongest supportive evidence once HO had developed. Of the non-pharmacological interventions, PLIMF was supported by the highest level of evidence; however, more research is needed to fully understand its role.

Physical and functional correlations of ankle-foot orthosis use in the rehabilitation of stroke patients.

OBJECTIVE: To examine factors associated with the use of ankle-foot orthoses (AFOs) in stroke patients undergoing rehabilitation. DESIGN: Retrospective cohort study of the frequency of AFO use. SETTING: Inpatient rehabilitation unit. PARTICIPANTS: Consecutive stroke patients (n = 423) admitted to an inpatient rehabilitation unit over a 10-year period. INTERVENTION: Discharge with AFO. MAIN OUTCOME MEASURES: Functional outcome measurement scores of patients who were and who were not prescribed an AFO were examined. The groups were compared by using admission and discharge Chedoke-McMaster Stroke Impairment Inventory (CM; each measure analyzed separately), FIMtrade mark instrument (walking, stairs, overall measures), and Berg Balance Scale scores. RESULTS: Ninety-three of the 423 patients (22%) were discharged with an AFO. Overall, they scored consistently lower than patients who were discharged without an AFO. Statistically significant differences (p <.001) were noted between AFO users and nonusers in admission and discharge scores in the arm, hand, leg, and foot components of the CM and the FIM stairs and walking component scores. Average admission and discharge Berg scores differed between the 2 groups (p =.005, p =.013, respectively). Overall FIM scores were also significantly different both at admission and discharge (p <.001, p =.025, respectively). CONCLUSION: Use of AFOs at discharge was associated with significantly lower admission and discharge CM scores of the arm, hand, leg, and foot; FIM walking and stairs scores; total FIM scores; and Berg Balance Scale scores.

Employment-related factors in chronic pain and chronic pain disability.

BACKGROUND: Disability is a multifactorial phenomenon. Social scientists suggest that nonclinical factors, including age, education, and job status, correlate with disability. OBJECTIVE: Do employment-related factors predict chronic pain and/or chronic pain disability? METHODOLOGY: The literature search identified 15 observational studies to provide the evidence about this question. RESULTS: Review topics included job satisfaction, type of work, modified work and work autonomy, other employment-related factors, and socioeconomic status. Most subjects in the studies had low back pain. The studies used return to work as an outcome predicting chronic pain disability. CONCLUSIONS: Lack of modified work and lack of work autonomy predicted chronic pain disability (level 2). There was limited evidence (level 3) that lack of job satisfaction, perception of difficult job conditions and demands, heavy physical demands of the job, private rather than public employment, and lower socioeconomic group predict chronic pain disability. The number of years employed varied as a predictor in different studies (level 4b).

Compensation and chronic pain.

BACKGROUND: The literature contains many different viewpoints on the impact of compensation on recovery from chronic pain. OBJECTIVE: What is the role of compensation in chronic pain and/or chronic pain disability? METHODOLOGY: The literature search identified 11 observational studies to provide evidence about this question. RESULTS: There is a paucity of high-quality data on the subject of the impact of compensation on chronic pain. This subject was reviewed under the headings of (1) injury claim rate and duration; (2) recovery; and (3) rehabilitation treatment programs. The studies were of subjects with musculoskeletal pain, mainly low back pain. CONCLUSIONS: Filing a compensation claim for costs, retaining a lawyer, or higher pain intensities were limited predictors of longer claims (level 3). As the ratio of compensation to preinjury wage increases, there is moderate evidence (level 2) that the duration of the claim increases and that disability is more likely. Compensation status, particularly combined with higher pain intensities, is associated with poorer prognosis after rehabilitation treatment programs (level 3).

Cardiovascular consequences of loss of supraspinal control of the sympathetic nervous system after spinal cord injury.

Spinal cord injury (SCI) with resultant quadriplegia or high paraplegia is associated with significant dysfunction of the sympathetic nervous system. This alteration of sympathetic nervous system activity occurs as a consequence of loss of supraspinal control of the sympathetic nervous system and is further complicated by at least three subsequent phenomena that occur below the level of SCI: reduced overall sympathetic activity, morphologic changes in sympathetic preganglionic neurons, and peripheral alpha-adrenoceptor hyperresponsiveness. Reduced sympathetic activity below the level of SCI appears to result in orthostatic hypotension, low resting blood pressure, loss of diurnal fluctuation of blood pressure, reflex bradycardia, and, rarely, cardiac arrest. Peripheral alpha-adrenoceptor hyperresponsiveness likely accounts for some, if not the majority, of the excessive pressor response in autonomic dysreflexia and may also contribute to decreased blood flow in the peripheral microcirculation, potentially increasing susceptibility to pressure sores. What has yet to be established is whether this alpha-adrenoceptor hyperresponsiveness is a consequence of receptor hypersensitivity or a failure of presynaptic reuptake of noradrenaline at the receptor level. Better understanding of the pathophysiology of sympathetic nervous system dysfunction after high-level SCI should allow development of more effective measures to manage clinical complications.

Trauma and fibromyalgia: is there an association and what does it mean?

OBJECTIVES: The primary objective is to review current research with respect to the role of trauma in fibromyalgia (FM). A secondary objective is to hypothesize which steps need to be taken, first to determine whether such an association truly exists, and second to clarify what such an association might mean. METHODS: An extensive literature review was undertaken, including Medline from 1979 to the present. RESULTS: The strongest evidence supporting an association between trauma and FM is a recently published Israeli study in which adults with neck injuries had greater than a 10-fold increased risk of developing FM within 1 year of their injury, compared with adults with lower extremity fractures (P= .001). Several other studies provide a hypothetical construct for such an association. These include studies on (1) postinjury sleep abnormalities; (2) local injury sites as a source of chronic distant regional pain; and (3) the concept of neuroplasticity. There are, however, several primary arguments against such an association: (1) FM may not be a distinct clinical entity; (2) FM may be a psychological, rather than physical, disease; (3) the evidence supporting any association is limited and not definitive; (4) the Israeli study, itself, has some methodological limitations; and (5) other factors may be more important than the injurious event in determining chronic symptoms after an acute injury. CONCLUSIONS: Although there is some evidence supporting an association between trauma and FM, the evidence is not definitive. Further prospective studies are needed to confirm this association and to identify whether trauma has a causal role.

Social issues in the rehabilitation of younger stroke patients.

OBJECTIVES: To study social factors and outcomes in stroke rehabilitation patients under the age of 50. STUDY DESIGN: Retrospective chart review examining (1) martial status and employment status on admission and at 3 months post discharge, (2) discharge destination, (3) the presence of absence of children under the age of 16, and (4) psychosocial difficulties as recorded by staff during hospitalization. SUBJECTS AND SETTING: Eighty-three consecutive stroke patients under the age of 50 admitted to a Canadian tertiary-care hospital rehabilitation unit. MAIN OUTCOME MEASURES: Discharge destination and primary caregiver at discharge, and return to work and marital separation 3 months after rehabilitation discharge. RESULTS: Of the 55 patients with spouses, 8 (14.5%) separated within 3 months of hospital discharge. Fifteen of the 83 patients (18.1%) were not able to return to their premorbid place of residence; 4 (4.8%) required institutionalization. Of the 64 patients employed outside the home or studying at the time of their stroke, only 13 (20.3%) were able to return to work within 3 months of their discharge to home. Only 9.4% of those working full-time were able to return to full-time employment. CONCLUSIONS: Rehabilitation of young stroke patients is associated with a variety of social problems, including marital breakup, child care responsibilities, and return to employment, which are uniquely important in this age group.

Antidepressants in rehabilitation.

Antidepressant medications have a variety of uses in addition to the treatment of depression. This article focuses on the two most widely used categories of antidepressants, tricyclic antidepressants (TCAs) and the newer selective serotonin reuptake inhibitors (SSRIs), and highlights their use in post-stroke depression and chronic pain.

Frequency of videofluoroscopic modified barium swallow studies and pneumonia in stroke rehabilitation patients: a comparative study.

OBJECTIVE: To study the association between the frequency of videofluoroscopic modified barium swallow (VMBS) studies and the incidence of pneumonia in stroke rehabilitation patients. DESIGN: Retrospective comparative study. SUBJECTS AND SETTING: Five hundred sixty-three consecutive stroke patients admitted to one hospital rehabilitation unit in London, Ontario, Canada were compared with 461 consecutive stroke patients admitted to another hospital rehabilitation unit in the same city. INTERVENTIONS: The number of initial and total VMBS studies and the timing from stroke onset to initial VMBS studies. MAIN OUTCOME MEASURE: Incidence of pneumonia. RESULTS: At the first hospital, 146 patients (25.9%) had 232 total VMBS studies performed, whereas at the second hospital 57 patients (12.4%) had 73 total studies (p<.001). For the first 15 days there was no significant difference in the number of initial VMBS studies performed (8.2% vs. 9.2%). There was a marked difference in the number of initial VMBS studies performed after 15 days (17.2% vs. 2.0%, p<.0001). The difference between the hospitals in the number of VMBS studies in patients with brain stem strokes was not statistically significant, but for patients with hemispheric stroke, the difference was statistically significant. Pneumonia developed in 12 patients at the first hospital (2.1%) and 10 patients at the second hospital (2.2%), a difference that was not significant. CONCLUSIONS: The more frequent use of VMBS beyond 15 days after stroke was not associated with a change in the incidence of pneumonia among hemispheric stroke rehabilitation patients, assuming the two units were otherwise similar.

Poststroke seizures in stroke rehabilitation patients.

The incidence, seizure type, location and type of stroke, and anticonvulsant medications, including adverse effects, were studied in a stroke rehabilitation population. Of 563 consecutive stroke patients admitted to the rehabilitation unit, 14 had a history of a seizure and were excluded from the primary study group. Of the remaining 549 stroke rehabilitation patients, 43 (7.8%) suffered a poststroke seizure (PSS). When only hemispheric patients were studied, the incidence of poststroke seizures rose to 43 of 460 (9.3%) as no brainstem stroke patients suffered seizures. The average age of the PSS patients was 55.4 years. The incidence of PSS in all stroke infarction patients was significantly smaller (22 of 450, 4.9%) when compared with hemorrhagic strokes (21 of 99, 21.2%) (P<.001). The incidence of PSS among hemispheric infarcts was 22 of 379 (5.8%) versus 21 of 81 (25.9%) of hemispheric hemorrhagic strokes (P<.001). Twenty-six PSS patients had primarily cortical involvement, 13 had both cortical and subcortical involvement, and only 4 had primarily subcortical involvement. Seizures occurred within the first 24 hours in 23.8% of stroke patients, 52.4% within the first week, in 66.7% within the first month, in 83.3% within the first 6 months, and in 88.1% within the first year. In the 43 patients with PSS, 19 (44.2%) were reportedly focal in nature, 12 (27.2%) were generalized, and 6 (14.0%) were focal with secondary generalization. Three (7.0%) were complex-partial seizures and 3(7.0%) were of an undetermined type. Of the 14 stroke rehabilitation patients excluded from the study group because of a prestroke seizure, 6 (42.9%) suffered a PSS in contrast to the 43 of 549 (7.8%) with no premorbid history of a seizure (P<.001).

Sudden death in the dysphagic stroke patient--a case of airway obstruction caused by a food bolus: a brief report.

The clinical events leading up to the sudden death of a dysphagic stroke patient with dementia is described. A 63-yr-old man sustained right thalamic and mid-brain infarctions. On the inpatient stroke rehabilitation ward, he exhibited significant impulsivity and dementia, the latter felt to be premorbid. The patient frequently coughed, and modified barium swallow testing showed dysphagia, with aspiration occurring only when consuming greater than teaspoon amounts of liquid. He subsequently died at home while eating a meal. Autopsy showed an intact large cheese ball (bocconcini) occluding the airway. Sudden death in the impulsive stroke patient secondary to airway occlusion by a food bolus has not previously been reported, although such patients seem to be at greater risk. New eating-related interventions are warranted for dysphagic patients who exhibit impulsivity. It is proposed that food particle size be limited to 1 cm2 and that such patients be closely monitored while eating.