Multilayer depressive symptom networks in adults with bodily pain living in precarious housing or homelessness.

Housing insecurity is associated with co-occurring depression and pain interfering with daily activities. Network analysis of depressive symptoms along with associated risk or protective exposures may identify potential targets for intervention in patients with co-occurring bodily pain. In a community-based sample of adults (n = 408) living in precarious housing or homelessness in Vancouver, Canada, depressive symptoms were measured by the Beck Depression Inventory; bodily pain and impact were assessed with the 36-item Short Form Health Survey. Network and bootstrap permutation analyses were used to compare depressive symptoms endorsed by Low versus Moderate-to-Severe (Mod + Pain) groups. Multilayer networks estimated the effects of risk and protective factors. The overall sample was comprised of 78% men, mean age 40.7 years, with 53% opioid use disorder and 14% major depressive disorder. The Mod + Pain group was characterized by multiple types of pain, more persistent pain, more severe depressive symptoms and a higher rate of suicidal ideation. Global network connectivity did not differ between the two pain groups. Suicidal ideation was a network hub only in the Mod + Pain group, with high centrality and a direct association with exposure to lifetime trauma. Antidepressant medications had limited impact on suicidal ideation. Guilt and increased feelings of failure represented symptoms from two other communities of network nodes, and completed the shortest pathway from trauma exposure through suicidal ideation, to the non-prescribed opioid exposure node. Interventions targeting these risk factors and symptoms could affect the progression of depression among precariously housed patients.

The American Congress of Rehabilitation Medicine Diagnostic Criteria for Mild Traumatic Brain Injury.

OBJECTIVE: To develop new diagnostic criteria for mild traumatic brain injury (TBI) that are appropriate for use across the lifespan and in sports, civilian trauma, and military settings. DESIGN: Rapid evidence reviews on 12 clinical questions and Delphi method for expert consensus. PARTICIPANTS: The Mild Traumatic Brain Injury Task Force of the American Congress of Rehabilitation Medicine Brain Injury Special Interest Group convened a Working Group of 17 members and an external interdisciplinary expert panel of 32 clinician-scientists. Public stakeholder feedback was analyzed from 68 individuals and 23 organizations. RESULTS: The first 2 Delphi votes asked the expert panel to rate their agreement with both the diagnostic criteria for mild TBI and the supporting evidence statements. In the first round, 10 of 12 evidence statements reached consensus agreement. Revised evidence statements underwent a second round of expert panel voting, where consensus was achieved for all. For the diagnostic criteria, the final agreement rate, after the third vote, was 90.7%. Public stakeholder feedback was incorporated into the diagnostic criteria revision prior to the third expert panel vote. A terminology question was added to the third round of Delphi voting, where 30 of 32 (93.8%) expert panel members agreed that 'the diagnostic label 'concussion' may be used interchangeably with 'mild TBI' when neuroimaging is normal or not clinically indicated.' CONCLUSIONS: New diagnostic criteria for mild TBI were developed through an evidence review and expert consensus process. Having unified diagnostic criteria for mild TBI can improve the quality and consistency of mild TBI research and clinical care.

Litigation, Performance Validity Testing, and Treatment Outcomes in Adults With Mild Traumatic Brain Injury.

OBJECTIVE: To investigate whether involvement in litigation and performance validity test (PVT) failure predict adherence to treatment and treatment outcomes in adults with persistent symptoms after mild traumatic brain injury (mTBI). SETTING: Outpatient concussion clinics in British Columbia, Canada. Participants were assessed at intake (average 12.9 weeks postinjury) and again following 3 to 4 months of rehabilitation. PARTICIPANTS: Adults who met the World Health Organization Neurotrauma Task Force definition of mTBI. Litigation status was known for 69 participants (n = 21 reported litigation), and 62 participants completed a PVT (n = 13 failed the Test of Memory Malingering) at clinic intake. DESIGN: Secondary analysis of a clinical trial (ClinicalTrials.gov #NCT03972579). MAIN MEASURES: Outcomes included number of completed sessions, homework adherence, symptoms (Rivermead Post Concussion Symptoms Questionnaire), disability ratings (World Health Organization Disability Assessment Schedule 2.0), and patient-rated global impression of change. RESULTS: We did not observe substantial differences in session and homework adherence associated with litigation or PVT failure. Disability and postconcussion symptoms generally improved with treatment. Involvement in litigation was associated with a smaller improvement in outcomes, particularly disability (B = 2.57, 95% confidence interval [CI] [0.25-4.89], P = .03) and patient-reported global impression of change (odds ratio [OR] = 4.19, 95% CI [1.40-12.57], P = .01). PVT failure was not associated with considerable differences in treatment outcomes. However, participants who failed the PVT had a higher rate of missing outcomes (31% vs 8%) and perceived somewhat less global improvement (OR = 3.47, 95% CI [0.86-14.04]; P = .08). CONCLUSION: Adults with mTBI who are in litigation or who failed PVTs tend to adhere to and improve following treatment. However, involvement in litigation may be associated with attenuated improvements, and pretreatment PVT failure may predict lower engagement in the treatment process.

Risk factors for hippocampal cavities in a marginally housed population.

Cavities in the hippocampus are morphological variants of uncertain significance. Aberrant neurodevelopment along with vascular and inflammatory etiologies have been proposed. We sought to characterize these cavities and their potential risk factors in a marginally housed population, with high rates of viral infection, addiction, and mental illness. (1) The volume of hippocampal cavities (HCavs) is greater in this highly multimorbid population compared to the general population. (2) Conventional vascular risk factors such as greater age and systolic blood pressure are associated with higher HCav volume. (3) Nonprescribed substance-related risk factors such as stimulant use or dependence, and smoking are associated with increased HCav volume independent of vascular risk factors. This is a retrospective analysis of an ongoing prospective study. We analyzed baseline data, including medical history, physical exam, psychiatric diagnosis, and MRI from a total of 375 participants. Hippocampal cavities were defined as spaces isointense to CSF on T1 MRI sequences, bounded on all sides by hippocampal tissue, with a volume of at least 1 mm3 . Risk factors were evaluated using negative binomial multiple regression. Stimulant use was reported by 87.3% of participants, with stimulant dependence diagnosed in 83.3% of participants. Prevalence of cavities was 71.6%, with a mean total bilateral HCav volume of 13.89 mm3 . On average, a 1 mmHg greater systolic blood pressure was associated with a 2.17% greater total HCav volume (95% CI = [0.57%, 3.79%], p = .0076), while each cigarette smoked per day trended toward a 2.69% greater total HCav volume (95% CI = [-0.87%, 5.54%], p = .058). A diagnosis of stimulant dependence was associated with a 95.6% greater total HCav volume (95% CI = [5.39%, 263.19%], p = .0335). Hypertension and diagnosis of stimulant dependence were associated with a greater total volume of HCav.

Dynamic networks of psychotic symptoms in adults living in precarious housing or homelessness.

BACKGROUND: People living in precarious housing or homelessness have higher than expected rates of psychotic disorders, persistent psychotic symptoms, and premature mortality. Psychotic symptoms can be modeled as a complex dynamic system, allowing assessment of roles for risk factors in symptom development, persistence, and contribution to premature mortality. METHOD: The severity of delusions, conceptual disorganization, hallucinations, suspiciousness, and unusual thought content was rated monthly over 5 years in a community sample of precariously housed/homeless adults (n = 375) in Vancouver, Canada. Multilevel vector auto-regression analysis was used to construct temporal, contemporaneous, and between-person symptom networks. Network measures were compared between participants with (n = 219) or without (n = 156) history of psychotic disorder using bootstrap and permutation analyses. Relationships between network connectivity and risk factors including homelessness, trauma, and substance dependence were estimated by multiple linear regression. The contribution of network measures to premature mortality was estimated by Cox proportional hazard models. RESULTS: Delusions and unusual thought content were central symptoms in the multilevel network. Each psychotic symptom was positively reinforcing over time, an effect most pronounced in participants with a history of psychotic disorder. Global connectivity was similar between those with and without such a history. Greater connectivity between symptoms was associated with methamphetamine dependence and past trauma exposure. Auto-regressive connectivity was associated with premature mortality in participants under age 55. CONCLUSIONS: Past and current experiences contribute to the severity and dynamic relationships between psychotic symptoms. Interrupting the self-perpetuating severity of psychotic symptoms in a vulnerable group of people could contribute to reducing premature mortality.

Feasibility of Concussion Rehabilitation Approaches Tailored to Psychological Coping Styles: A Randomized Controlled Trial.

OBJECTIVE: To evaluate the feasibility of a clinical trial involving participants with concussion randomized to treatments designed to address fear avoidance or endurance coping, which are risk factors for disability. A secondary objective was to evaluate whether each treatment could affect selective change on targeted coping outcomes. DESIGN: Randomized controlled trial. SETTING: Outpatient concussion clinics. PARTICIPANTS: Adults (N=73, mean age=42.5y) who had persistent postconcussion symptoms and high avoidance or endurance behavior were enrolled at a mean of 12.9 weeks post injury. Ten participants did not complete treatment. INTERVENTIONS: Participants were randomized to an interdisciplinary rehabilitation program delivered via videoconferencing and tailored to avoidance coping (graded exposure therapy [GET]) or endurance coping (operant condition-based pacing strategies plus mindfulness training [Pacing+]). MAIN OUTCOME MEASURES: Feasibility outcomes included screening efficiency, accrual, credibility, treatment fidelity, adherence, and retention. Avoidance was measured with the Fear Avoidance Behavior after Traumatic Brain Injury Questionnaire and endurance behavior with the Behavioral Response to Illness Questionnaire. RESULTS: Screening efficiency, or the proportion of clinic patients who were assessed for eligibility, was 44.5% (275 of 618). A total of 65.8% (73 of 111) of eligible patients were randomized (37 to GET, 36 to Pacing+), meeting accrual targets; 91.7% (55 of 60) of participants perceived treatment as credible. Therapists covered a mean of 96.8% of essential prescribed elements, indicating excellent fidelity. The majority (71.2%; 47 of 66) of participants consistently attended treatment sessions and completed between-session homework. Retention was strong, with 65 of 73 (89%) randomized participants completing the outcome assessment. GET was associated with greater posttreatment reductions in avoidance behavior compared with Pacing+ (Cohen's drepeated measures, 0.81), whereas the treatment approach-specific effect of Pacing+ on endurance behavior was less pronounced (Cohen's drepeated measures, 0.39). CONCLUSIONS: These findings support a future efficacy-focused clinical trial. GET has the potential to selectively reduce fear avoidance behavior after concussion, and, via this mechanism, to prevent or reduce disability.

Characterizing Traumatic Brain Injury and Its Association with Losing Stable Housing in a Community-based Sample.

OBJECTIVE: Traumatic brain injury (TBI) is increasingly recognized as a common and impactful health determinant in homeless and precariously housed populations. We sought to describe the history of TBI in a precariously housed sample and evaluate how TBI was associated with the initial loss and lifetime duration of homelessness and precarious housing. METHOD: We characterized the prevalence, mechanisms, and sex difference of lifetime TBI in a precariously housed sample. We also examined the impact of TBI severity and timing on becoming and staying homeless or precariously housed; 285 precariously housed participants completed the Brain Injury Screening Questionnaire in addition to other health assessments. RESULTS: A history of TBI was reported in 82.1% of the sample, with 64.6% reporting > 1 TBI, and 21.4% reporting a moderate or severe TBI. Assault was the most common mechanism of injury overall, and females reported significantly more traumatic brain injuries due to physical abuse than males (adjusted OR = 1.26, 95% CI = 1.14 to 1.39, P < 0.0001). The first moderate or severe TBI was significantly closer to the first experience of homelessness (b = 2.79, P = 0.003) and precarious housing (b = 2.69, P < 0.0001) than was the first mild TBI. In participants who received their first TBI prior to becoming homeless or precariously housed, traumatic brain injuries more proximal to the initial loss of stable housing were associated with a longer lifetime duration of homelessness (RR = 1.04, 95% CI = 1.02 to 1.06, P < 0.0001) and precarious housing (RR = 1.03, 95% CI = 1.01 to 1.04, P < 0.0001). CONCLUSIONS: These findings demonstrate the high prevalence of TBI in this vulnerable population, and that aspects of TBI severity and timing are associated with the loss and lifetime duration of stable housing.

Criterion validity of the brief test of adult cognition by telephone (BTACT) for mild traumatic brain injury.

OBJECTIVES: There is a growing demand for remote assessment options for measuring cognition after mild traumatic brain injury (mTBI). The current study evaluated the criterion validity of the Brief Test of Adult Cognition by Telephone (BTACT) in distinguishing between adults with mTBI and trauma controls (TC) who sustained injuries not involving the head or neck. METHODS: The BTACT was administered to the mTBI (n = 46) and TC (n = 35) groups at 1-2 weeks post-injury. Participants also completed the Rivermead Post Concussion Symptoms Questionnaire. RESULTS: The BTACT global composite score did not significantly differ between the groups (t(79) = -1.04, p = 0.30); the effect size was small (d = 0.23). In receiver operating characteristic curve analyses, the BTACT demonstrated poor accuracy in differentiating between the groups (AUC = 0.567, SE = 0.065, 95% CI [0.44, 0.69]). The BTACT's ability to discriminate between mTBI and TCs did not improve after excluding mTBI participants (n = 15) who denied ongoing cognitive symptoms (AUC = 0.567, SE = 0.072, 95% CI [0.43, 0.71]). CONCLUSIONS: The BTACT may lack sensitivity to subacute cognitive impairment attributable to mTBI (i.e., not explained by bodily pain, post-traumatic stress, and other nonspecific effects of injury).

History of Functional Somatic Syndromes and Persistent Symptoms After Mild Traumatic Brain Injury.

OBJECTIVE: Somatization is thought to underlie functional somatic syndromes (FSSs) and may also contribute to prolonged symptoms after mild traumatic brain injury (mTBI). The investigators evaluated the prevalence of FSSs in patients seeking specialty care after mTBI and whether a history of FSSs was associated with symptom persistence. METHODS: A total of 142 patients with mTBI completed questionnaires regarding demographic information, injury characteristics, and medical history, including history of diagnosed FSSs at clinic intake (mean=41 days postinjury [SD=22.41]). Postconcussion symptoms were assessed at clinic intake and again 1 and 3 months later. A linear mixed-effects model was used to determine whether history of FSSs was related to persistent mTBI symptoms over time. RESULTS: A history of at least one FSS was reported by 20.4% of patients. In the linear mixed model, postconcussion symptom scores were not significantly different over time among patients with a history of one or more FSSs or two or more FSSs from those with no FSSs. A history of one or more FSSs or two or more FSSs (versus no FSS) was not associated with increased odds of severe postconcussion symptoms at clinic intake (one or more FSSs: odds ratio=0.88, 95% CI=0.38-2.03; two or more FSSs: odds ratio=1.78, 95% CI=0.45-7.03), at the 1-month follow-up visit (one or more FSSs: odds ratio=0.57, 95% CI=0.22-1.45; two or more FSSs: odds ratio=0.57, 95% CI=0.14-2.37), or at the 3-month follow-up visit (one or more FSSs: odds ratio=0.97, 95% CI=0.36-2.63; two or more FSSs: odds ratio=1.27, 95% CI=0.29-5.65). CONCLUSIONS: In this sample, the prevalence rates of FSSs were higher than rates previously reported for the general population. However, FSS history did not predict higher postconcussion symptom burden at clinic intake or persistence over the following 3 months. Further research is needed to clarify the potential role of somatization in poor mTBI outcome.

De-implementing Prolonged Rest Advice for Concussion in Primary Care Settings: A Pilot Stepped Wedge Cluster Randomized Trial.

OBJECTIVE: To evaluate the feasibility and preliminary efficacy of a de-implementation intervention to support return-to-activity guideline use after concussion. SETTING: Community. PARTICIPANTS: Family physicians in community practice (n = 21 at 5 clinics). DESIGN: Pilot stepped wedge cluster randomized trial with qualitative interviews. Training on new guidelines for return to activity after concussion was provided in education outreach visits. MAIN MEASURES: The primary feasibility outcomes were recruitment, retention, and postencounter form completion (physicians prospectively recorded what they did for each new patient with concussion). Efficacy indicators included a knowledge test and guideline compliance based on postencounter form data. Qualitative interviews covered Theoretical Domains Framework elements. RESULTS: Recruitment, retention, and postencounter form completion rates all fell below feasibility benchmarks. Family physicians demonstrated increased knowledge about the return-to-activity guideline (M = 8.8 true-false items correct out of 10 after vs 6.3 before) and improved guideline adherence (86% after vs 25% before) after the training. Qualitative interviews revealed important barriers (eg, beliefs about contraindications) and facilitators (eg, patient handouts) to behavior change. CONCLUSIONS: Education outreach visits might facilitate de-implementation of prolonged rest advice after concussion, but methodological changes will be necessary to improve the feasibility of a larger trial. The qualitative findings highlight opportunities for refining the intervention.

Preseason Vestibular Ocular Motor Screening in Children and Adolescents.

OBJECTIVES: The primary purpose of this study was to examine vestibular/ocular motor screening (VOMS) test performance in a sample of healthy youth ice hockey players. A particular focus was to investigate the potential effects of age and pre-existing health conditions, including concussion history, attention-deficit/hyperactivity disorder (ADHD), learning disability (LD), headaches/migraines, and depression/anxiety on preseason baseline VOMS performance, including the near point of convergence (NPC) distance. DESIGN: Cross-sectional cohort. SETTING: Outpatient physiotherapy clinic. PARTICIPANTS: Three hundred eighty-seven male youth hockey players, with an average age of 11.9 years (SD = 2.2, range = 8-17), completed the VOMS and responded to self- or parent-reported demographic and medical history questionnaires during preseason baseline assessments. INDEPENDENT VARIABLES ASSESSED: Age, sex, and mental and physical health history including ADHD, headaches, depression, anxiety, migraine, and LD. OUTCOME MEASURE: Vestibular/ocular motor screening. RESULTS: The large majority of boys scored within normal limits on the VOMS, ie, they reported no symptom provocation of more than 2 points on any VOMS subset (89%) and had a normal NPC distance, ie, <5 cm (78%). The individual VOMS subtests had low abnormality rates, and demographic and pre-existing health conditions, such as age, headache or migraine history, previous neurodevelopmental conditions, or mental health problems, were not associated with clinically meaningful symptom provocation during the VOMS. CONCLUSIONS: There was a low rate of abnormal findings for the individual VOMS subtests, with the exception of NPC distance, among male youth hockey players during preseason assessment.

Characterization of Bodily Pain and Use of Both Prescription and Non-Prescription Opioids in Tenants of Precarious Housing.

BACKGROUND: opioid use, which includes both prescribed and non-prescribed drugs, is relatively common amongst marginalized populations. Past research has shown that among those who use non-prescribed or diverted opioids recreationally, many were first exposed to the drug as prescribed pain medication. Objective: to better understand the relationship between pain and opioid use in tenants of precarious housing. Methods: in the present study, 440 individuals from a cohort living in homeless or precariously housed conditions in a neighborhood with high rates of poverty and drug use were interviewed for their bodily pain and opioid use. We examined the relationship between bodily pain levels, assessed using the Maudsley Addiction Profile questionnaire, and prescribed, non-prescribed and combined self-reported opioid use in the prior 28 days assessed using the Timeline Followback and Doctor-Prescribed Medication Timeline Followback questionnaires. Results: Analysis of the results indicated that sex (female), age (younger) and early exposure to opioids (≤ age 18) predicted current opioid use, but there was no association between current bodily pain levels and opioid use. Conclusions: these unexpected findings indicate the complex nature of the relationship between pain and opioid use in this population.

Cerebral Small Vessel Disease, Risk Factors, and Cognition in Tenants of Precarious Housing.

BACKGROUND AND PURPOSE: We aim to describe the burden, characteristics, and cognitive associations of cerebral small vessel disease in a Canadian sample living with multimorbidity in precarious housing. METHODS: Participants received T1, T2-fluid-attenuated inversion recovery, and susceptibility-weighted imaging 3T magnetic resonance imaging sequences and comprehensive clinical, laboratory, and cognitive assessments. Cerebral small vessel disease burden was characterized using a modified Small Vessel Disease (mSVD) score. One point each was given for moderate-severe white matter hyperintensities, ≥1 cerebral microbleeds, and ≥1 lacune. Multivariable regression explored associations between mSVD score, risk factors, and cognitive performance. RESULTS: Median age of the 228 participants (77% male) was 44.7 years (range, 23.3-63.2). In n=188 participants with consistent good quality magnetic resonance imaging sequences, mSVD scores were 0 (n=127, 68%), 1 (n=50, 27%), and 2 (n=11, 6%). Overall, one-third had an mSVD ≥1 n=61 (32%); this proportion was unchanged when adding participants with missing sequences n=72/228 (32%). The most prevalent feature was white matter hyperintensities 53/218 (24%) then cerebral microbleed 16/191 (8%) and lacunes 16/228 (7%). Older age (odds ratio, 1.10 [95% CI, 1.05-1.15], P<0.001), higher diastolic blood pressure (odds ratio, 1.05 [95% CI, 1.01-1.09], P=0.008), and a history of injection drug use (odds ratio, 3.13 [95% CI, 1.07-9.16], P=0.037) had significant independent associations with a mSVD score of ≥1 in multivariable analysis. mSVD ≥1 was associated with lower performance on tests of verbal memory, sustained attention, and decision-making, contributing 4% to 5% of the variance in each cognitive domain. CONCLUSIONS: The 32% prevalence of cerebral small vessel disease in this young, socially marginalized cohort was higher than expected for age and was associated with poorer cognitive performance.

Associations of substance use, psychosis, and mortality among people living in precarious housing or homelessness: A longitudinal, community-based study in Vancouver, Canada.

BACKGROUND: The "trimorbidity" of substance use disorder and mental and physical illness is associated with living in precarious housing or homelessness. The extent to which substance use increases risk of psychosis and both contribute to mortality needs investigation in longitudinal studies. METHODS AND FINDINGS: A community-based sample of 437 adults (330 men, mean [SD] age 40.6 [11.2] years) living in Vancouver, Canada, completed baseline assessments between November 2008 and October 2015. Follow-up was monthly for a median 6.3 years (interquartile range 3.1-8.6). Use of tobacco, alcohol, cannabis, cocaine, methamphetamine, and opioids was assessed by interview and urine drug screen; severity of psychosis was also assessed. Mortality (up to November 15, 2018) was assessed from coroner's reports and hospital records. Using data from monthly visits (mean 9.8, SD 3.6) over the first year after study entry, mixed-effects logistic regression analysis examined relationships between risk factors and psychotic features. A past history of psychotic disorder was common (60.9%). Nonprescribed substance use included tobacco (89.0%), alcohol (77.5%), cocaine (73.2%), cannabis (72.8%), opioids (51.0%), and methamphetamine (46.5%). During the same year, 79.3% of participants reported psychotic features at least once. Greater risk was associated with number of days using methamphetamine (adjusted odds ratio [aOR] 1.14, 95% confidence interval [CI] 1.05-1.24, p = 0.001), alcohol (aOR 1.09, 95% CI 1.01-1.18, p = 0.04), and cannabis (aOR 1.08, 95% CI 1.02-1.14, p = 0.008), adjusted for demographic factors and history of past psychotic disorder. Greater exposure to concurrent month trauma was associated with increased odds of psychosis (adjusted model aOR 1.54, 95% CI 1.19-2.00, p = 0.001). There was no evidence for interactions or reverse associations between psychotic features and time-varying risk factors. During 2,481 total person years of observation, 79 participants died (18.1%). Causes of death were physical illness (40.5%), accidental overdose (35.4%), trauma (5.1%), suicide (1.3%), and unknown (17.7%). A multivariable Cox proportional hazard model indicated baseline alcohol dependence (adjusted hazard ratio [aHR] 1.83, 95% CI 1.09-3.07, p = 0.02), and evidence of hepatic fibrosis (aHR 1.81, 95% CI 1.08-3.03, p = 0.02) were risk factors for mortality. Among those under age 55 years, a history of a psychotic disorder was a risk factor for mortality (aHR 2.38, 95% CI 1.03-5.51, p = 0.04, adjusted for alcohol dependence at baseline, human immunodeficiency virus [HIV], and hepatic fibrosis). The primary study limitation concerns generalizability: conclusions from a community-based, diagnostically heterogeneous sample may not apply to specific diagnostic groups in a clinical setting. Because one-third of participants grew up in foster care or were adopted, useful family history information was not obtainable. CONCLUSIONS: In this study, we found methamphetamine, alcohol, and cannabis use were associated with higher risk for psychotic features, as were a past history of psychotic disorder, and experiencing traumatic events. We found that alcohol dependence, hepatic fibrosis, and, only among participants <55 years of age, history of a psychotic disorder were associated with greater risk for mortality. Modifiable risk factors in people living in precarious housing or homelessness can be a focus for interventions.

Management of Concussion and Mild Traumatic Brain Injury: A Synthesis of Practice Guidelines.

At least 3 million Americans sustain a mild traumatic brain injury (mTBI) each year, and 1 in 5 have symptoms that persist beyond 1 month. Standards of mTBI care have evolved rapidly, with numerous expert consensus statements and clinical practice guidelines published in the last 5 years. This Special Communication synthesizes recent expert consensus statements and evidenced-based clinical practice guidelines for civilians, athletes, military, and pediatric populations for clinicians practicing outside of specialty mTBI clinics, including primary care providers. The article offers guidance on key clinical decisions in mTBI care and highlights priority interventions that can be initiated in primary care to prevent chronicity.

Autoreactivity to Sulfatide by Human Invariant NKT Cells.

Invariant NKT (iNKT) cells are innate-like lymphocytes that recognize lipid Ags presented by CD1d. The prototypical Ag, α-galactosylceramide, strongly activates human and mouse iNKT cells, leading to the assumption that iNKT cell physiology in human and mouse is similar. In this article, we report the surprising finding that human, but not mouse, iNKT cells directly recognize myelin-derived sulfatide presented by CD1d. We propose that sulfatide is recognized only by human iNKT cells because of the unique positioning of the 3-O-sulfated ß-galactose headgroup. Surface plasmon resonance shows that the affinity of human CD1d-sulfatide for the iNKT cell receptor is relatively low compared with CD1d-α-galactosylceramide (KD of 19-26 µM versus 1 µM). Apolipoprotein E isolated from human cerebrospinal fluid carries sulfatide that can be captured by APCs and presented by CD1d to iNKT cells. APCs from patients with metachromatic leukodystrophy, who accumulate sulfatides due to a deficiency in arylsulfatase-A, directly activate iNKT cells. Thus, we have identified sulfatide as a self-lipid recognized by human iNKT cells and propose that sulfatide recognition by innate T cells may be an important pathologic feature of neuroinflammatory disease and that sulfatide in APCs may contribute to the endogenous pathway of iNKT cell activation.

Antidepressants for depression after concussion and traumatic brain injury are still best practice.

BACKGROUND: Depression is a common complication of traumatic brain injury (TBI). New evidence suggests that antidepressant medication may be no more effective than placebo in this population. MAIN BODY: Selective serotonin reuptake inhibitors are recommended as first-line treatment for depression in contemporary expert consensus clinical practice guidelines for management of TBI. This recommendation is based on multiple prior meta-analyses of clinical trials in depression after TBI as well as depression in the general population. The evidence is mixed. A recent clinical trial and new meta-analysis including that trial found no benefit of antidepressants for depression following TBI. We argue that this finding should not change practice, i.e., patients who present with depression after TBI should still be considered for antidepressant treatment, because they may (1) benefit from robust placebo effects, (2) benefit from an alternative or adjunctive medication if the agent prescribed first does not achieve a depression remission, and (3) make improvements that are not captured well by traditional depression outcome measures, which are confounded by TBI sequelae. Patients with mild TBI are especially appropriate for antidepressant therapy because they, on average, more closely resemble patients with no known TBI history enrolled in typical primary Major Depressive Disorder clinical trials than patients enrolled in TBI trials in placebo-controlled trials published to date. CONCLUSION: TBI, and especially mild TBI, is not a contraindication for antidepressant therapy. Health providers should routinely screen and initiate treatment for depression after TBI.

Characterization of mental health in cannabis dispensary users, using structured clinical interviews and standardized assessment instruments.

BACKGROUND: Cannabis is commonly used for its medical properties. In particular, cannabis is purported to have beneficial effects on a wide range of neuropsychiatric conditions. Studies assessing mental health in cannabis dispensary users typically evaluate symptoms using self-report check lists, which provide limited information about symptom severity, and whether subjects meet criteria for a psychiatric diagnosis. There is, therefore, a need for studies which assess mental health in dispensary users with standardized and well validated scientific instruments, such as those used in clinical drug trials. METHODS: One hundred medical cannabis users were recruited from a community dispensary. All subjects completed a structured clinical interview with the Mini-International Neuropsychiatric Interview (MINI). Subjects also completed the Perceived Stress Scale-10, PROMIS Fatigue Scale, PROMIS Sleep Disturbance Scale, Beck Depression Inventory, the Patient Health Questionnaire-15 and the Brief Pain Inventory. Details about cannabis use were also recorded. RESULTS: Lifetime prevalence of mental illness in this cohort was high, and a large proportion of subjects endorsed psychological symptoms. The proportion of subjects who met criteria for classification of a current psychiatric disorder was low for mood disorders, but high for anxiety disorders and substance abuse/dependence. Cannabis use differed between the main psychiatric conditions. CONCLUSIONS: The present results indicate that rates of mental illness may be high in medical cannabis dispensary users. Use of structured clinical assessments combined with standardized symptom severity questionnaires provide a feasible way to provide a more rigorous and detailed evaluation of conditions and symptoms in this population.

The effects of enhanced attention and working memory on smooth pursuit eye movement.

It has long been suggested that increasing attentional demands can alter smooth pursuit eye movements, but the precise nature of the changes generated is not clear. Our goal was to examine smooth pursuit with a task that enhanced attention to the target and that increased demands on working memory, without distracting from the target. 15 subjects tracked a target moving around a predictable circular trajectory at a constant tangential velocity. An n-back task with two levels of additional working memory load was integrated into the pursuit target to increase cognitive demands. In the single-task conditions, subjects either performed pursuit alone or the n-back task with a stationary target. In the dual-task conditions, pursuit and the n-back task were performed together. Performance of the n-back tasks was not impaired by simultaneous smooth pursuit. The n-back tasks had negligible effects on horizontal or vertical pursuit gain, but generated increased phase lag and reduced the variability of position error during pursuit. Increasing the difficulty of the n-back task further reduced the variability of position errors. We conclude that enhanced attention does not alter the velocity gain of smooth pursuit but rather improves its consistency. As long as attention remains focused on the target, increased attentional demands further reduce pursuit variability. Increases in phase lag may serve to improve attentional processing of the target.

Work Productivity Loss After Mild Traumatic Brain Injury.

OBJECTIVES: To examine the completeness of return to work (RTW) and the degree of productivity loss in individuals who do achieve a complete RTW after mild traumatic brain injury (MTBI). DESIGN: Multisite prospective cohort. SETTING: Outpatient concussion clinics. PARTICIPANTS: Patients (N=79; mean age, 41.5y; 55.7% women) who sustained an MTBI and were employed at the time of the injury. Participants were enrolled at their first clinic visit and assessed by telephone 6 to 8 months postinjury. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Structured interview of RTW status, British Columbia Postconcussion Symptom Inventory (BC-PSI), Lam Employment Absence and Productivity Scale (LEAPS), Mini International Neuropsychiatric Interview, and brief pain questionnaire. Participants who endorsed symptoms from ≥3 categories with at least moderate severity on the BC-PSI were considered to meet International Classification of Diseases, 10th Revision criteria for postconcussional syndrome. RTW status was classified as complete if participants returned to their preinjury job with the same hours and responsibilities or to a new job that was at least as demanding. RESULTS: Of the 46 patients (58.2%) who achieved an RTW, 33 (71.7%) had a complete RTW. Participants with complete RTW had high rates of postconcussional syndrome (44.5%) and comorbid depression (18.2%), anxiety disorder (24.2%), and bodily pain (30.3%). They also reported productivity loss on the LEAPS, such as "getting less work done" (60.6%) and "making more mistakes" (42.4%). In a regression model, productivity loss was predicted by the presence of postconcussional syndrome and a comorbid psychiatric condition, but not bodily pain. CONCLUSIONS: Even in patients who RTW after MTBI, detailed assessment revealed underemployment and productivity loss associated with residual symptoms and psychiatric complications.