Apathy and Depression Among People Aging With Traumatic Brain Injury: Relationships to Cognitive Performance and Psychosocial Functioning.

OBJECTIVE: Apathy and depression are both common after moderate to severe traumatic brain injury (TBI) and may be especially important to distinguish in older adults with TBI. The authors examined apathy and depression in relation to cognitive performance domains and their potentially unique contribution to psychosocial functioning in this patient population. METHODS: A total of 106 participants (mean±SD age=64±8 years) with chronic moderate to severe TBI (≥1 year) completed questionnaires assessing severity of apathy (Frontal Systems Behavior Scale-apathy subscale) and depression (Geriatric Depression Scale-15) symptoms, health-related quality of life (HRQoL), and societal participation. Participants also completed neuropsychological tests of episodic memory, processing speed, and executive functioning. RESULTS: Apathy symptom severity was significantly associated with all cognitive performances in correlations adjusted for the familywise error rate; a relationship with executive functioning remained after controlling for demographic and injury variables. Depression symptom severity was not significantly associated with cognition after statistical correction. Both symptomatologies uniquely contributed to HRQoL. Only depression symptoms contributed to societal participation. On the basis of clinical cutoffs, half the sample had neither depression nor apathy, approximately 25% met criteria for only apathy, and 25% had both apathy and depression. The combined presence of clinical depression and apathy was associated with worse HRQoL and societal participation. CONCLUSIONS: This is the first study to examine apathy and depression in relation to cognition and psychosocial functioning in an older sample with a history of TBI. Findings suggest that the two syndromes can be dissociated in clinically meaningful ways, which may help to refine psychiatric and behavioral interventions in this vulnerable population.

The Effects of Repetitive Head Impact Exposure on Mental Health Symptoms Following Traumatic Brain Injury.

OBJECTIVE: This study aimed to characterize the types and timing of repetitive head impact (RHI) exposures in individuals with moderate to severe traumatic brain injury (TBI) and to examine the effects of RHI exposures on mental health outcomes. SETTING: TBI Model Systems National Database. PARTICIPANTS: 447 patients with moderate to severe TBI who reported RHI exposure between 2015 and 2022. DESIGN: Secondary data analysis. MAIN MEASURES: RHI exposures reported on the Ohio State University TBI Identification Method (OSU TBI-ID) were characterized by exposure category, duration, and timing relative to the index TBI. Mental health outcomes were evaluated at the 5-year follow-up assessment using the Patient Health Questionnaire-9 (PHQ-9) for depression symptoms and the Generalized Anxiety Disorder-7 (GAD-7) for anxiety symptoms. RESULTS: The majority of RHI exposures were sports-related (61.1%), followed by other causes (20.8%; including falls), repetitive violence/assault (18.8%), and military exposures (6.7%). Males predominantly reported sports and military exposures, while a larger proportion of females reported violence and falls. Sports exposures were most common before the index TBI, while exposures from falls and violence/abuse were most common after TBI. RHI exposures occurring after the index TBI were associated with higher levels of depression (ß = 5.05; 95% CI, 1.59-8.50) and anxiety (ß = 4.53; 95% CI, 1.02-8.05) symptoms than exposures before the index TBI. CONCLUSION: The findings emphasize the need to consider RHI exposures and their interaction with TBI when assessing mental health outcomes. Understanding the prevalence and challenges associated with RHI post-TBI can inform targeted interventions and improve the well-being of individuals with TBI. Preventive measures and ongoing care should be implemented to address the risks posed by RHI, particularly in individuals with prior TBI, especially surrounding fall and violence/abuse prevention.

Characterization and Treatment of Chronic Pain After Traumatic Brain Injury-Comparison of Characteristics Between Individuals With Current Pain, Past Pain, and No Pain: A NIDILRR and VA TBI Model Systems Collaborative Project.

OBJECTIVE: To estimate the prevalence of chronic pain after traumatic brain injury (TBI) and identify characteristics that differ from those without chronic pain. SETTING: Community. PARTICIPANTS: A total of 3804 TBI Model Systems (TBIMS) participants who completed the Pain Survey at TBIMS follow-up. DESIGN: A multisite, cross-sectional observational cohort study. MAIN OUTCOME MEASURES: Functional outcomes, pain experience, and treatment. RESULTS: 46% reported current chronic pain, 14% reported past (post-injury) chronic pain, and 40% reported no chronic pain. Bivariate differences in sociodemographic and injury characteristics between the 3 pain groups were generally small in effect size, reflecting little clinical difference. However, medium effect sizes were seen for all functional outcomes, such that individuals with current chronic pain had worse functional outcomes compared with individuals in the past pain or no pain groups. Treatment utilization rates were higher for individuals with current chronic pain compared with past pain, with medical treatments being most frequently utilized. Individuals with past pain perceived more improvement with treatment than did those with current chronic pain as represented by a large effect size. CONCLUSIONS: Chronic pain affects approximately 60% of those living with TBI. The implications of chronic pain for functional outcomes support inclusion of pain metrics in prognostic models and observational studies in this population. Future research is needed to proactively identify those at risk for the development of chronic pain and determine the efficacy and access to pain treatment.

Associations of Chronic Pain With Psychosocial Outcomes After Traumatic Brain Injury: A NIDILRR and VA TBI Model Systems Collaborative Project.

OBJECTIVE: To examine the differences in participation, life satisfaction, and psychosocial outcomes among individuals with traumatic brain injury (TBI) endorsing current, past, or no chronic pain. SETTING: Community. PARTICIPANTS: Three thousand eight hundred four TBI Model Systems participants 1 to 30 years of age postinjury classified into 1 of 3 groups based on their pain experience: current pain, past pain, no pain completed a Pain Survey at their usual follow-up appointment which on average was approximately 8 years postinjury. DESIGN: Multisite, cross-sectional observational cohort study. MAIN OUTCOME MEASURES: Sociodemographic and injury characteristics and psychosocial outcomes (ie, satisfaction with life, depression, anxiety, posttraumatic stress disorder [PTSD], sleep quality, community participation). RESULTS: Persons with current chronic pain demonstrated higher scores on measures of PTSD, anxiety, and depression, and the lower scores on measures of sleep quality, community participation and satisfaction with life. Those with resolved past pain had mean scores for these outcomes that were all between the current and no chronic pain groups, but always closest to the no pain group. After adjusting for sociodemographic and function in multivariate analysis, having current chronic pain was associated with more negative psychosocial outcomes. The largest effect sizes (ES; in absolute value) were observed for the PTSD, depression, anxiety, and sleep quality measures (ES = 0.52-0.81) when comparing current pain to past or no pain, smaller ES were observed for life satisfaction (ES = 0.22-0.37) and out and about participation (ES = 0.16-0.18). When comparing past and no pain groups, adjusted ES were generally small for life satisfaction, PTSD, depression, anxiety, and sleep quality (ES = 0.10-0.23) and minimal for participation outcomes (ES = 0.02-0.06). CONCLUSIONS: Chronic pain is prevalent among individuals with TBI and is associated with poorer psychosocial outcomes, especially for PTSD, depression, anxiety, and sleep disturbance. The results from this study highlight the presence of modifiable comorbidities among those with chronic pain and TBI. Persons who experience persistent pain following TBI may be at greater risk for worse psychosocial outcomes.

The Interaction of Opiate Misuse and Marijuana Use on Behavioral Health Outcomes Using the Traumatic Brain Injury Model Systems Pain Collaborative Dataset.

OBJECTIVE: To determine if the interaction of opiate misuse and marijuana use frequency is associated with behavioral health outcomes. SETTING: Community. PARTICIPANTS: Three thousand seven hundred fifty participants enrolled in the Traumatic Brain Injury Model Systems who completed the Pain Survey and had complete opioid use and marijuana use information. DESIGN: Cross-sectional, secondary analysis from a multisite observational cohort. MAIN OUTCOME MEASURES: Clinically significant behavioral health symptoms for posttraumatic stress disorder (PTSD), depression, anxiety, and sleep quality. RESULTS: Three thousand five hundred thirty-five (94.3%) participants did not misuse opiates, 215 (5.7%) did misuse opiates (taking more opioid pain medication than prescribed and/or using nonprescription opioid pain medication); 2683 (70.5%) participants did not use marijuana, 353 (9.3%) occasionally used marijuana (less than once a week), and 714 (18.8%) regularly used marijuana (once a week or more frequently). There was a statistically significant relationship (P < .05) between the interaction of opiate misuse and marijuana use frequency and all behavioral health outcomes and several covariates (age, sex, cause of injury, severity of injury, and pain group category). Pairwise comparisons confirm that statistically significant associations on behavioral health outcomes are driven by endorsing opiate misuse and/or regular marijuana use, but occasional marijuana use was not associated. CONCLUSIONS: Higher odds of clinically significant PTSD, depression, anxiety, and poor sleep quality are present in people with traumatic brain injury (TBI) who misuse opiates and/or who use marijuana regularly. In the absence of opiate misuse, regular marijuana use had higher odds of worse behavioral health outcomes than occasional and no use. The interaction of opiate misuse and regular marijuana use yielded the highest odds. Individuals with TBI should be informed of the relationship of substance use and behavioral health outcomes and that current chronic pain may mediate the association.

Developing multidimensional participation profiles after traumatic brain injury: a TBI model systems study.

Purpose. To characterize societal participation profiles after moderate-severe traumatic brain injury (TBI) along objective (Frequency) and subjective (Satisfaction, Importance, Enfranchisement) dimensions.Materials and Methods. We conducted secondary analyses of a TBI Model Systems sub-study (N = 408). Multiaxial assessment of participation included the Participation Assessment with Recombined Tools-Objective and -Subjective questionnaires (Participation Frequency and Importance/Satisfaction, respectively) and the Enfranchisement Scale. Participants provided responses via telephone interview 1-15 years post-injury. Multidimensional participation profiles (classes) were extracted using latent profile analysis.Results. A 4-class solution was identified as providing maximal statistical separation between profiles and being clinically meaningful based on profile demographic features. One profile group (48.5% of the sample) exhibited the "best" participation profile (High Frequency, Satisfaction, Importance, and Enfranchisement) and was also the most advantaged according to socioeconomic indicators. Other profile groups showed appreciable heterogeneity across participation dimensions. Age, race/ethnicity, education level, ability to drive, and urbanicity were features that varied between profiles.Conclusions. Societal participation is a critical, but inherently complex, TBI outcome that may not be adequately captured by a single index. Our data underscore the importance of a multidimensional approach to participation assessment and interpretation using profiles. The use of participation profiles may promote precision health interventions for community integration.Implications for RehabilitationOur study found unidimensional measures of societal participation in traumatic brain injury (TBI) populations that focus exclusively on frequency indicators may be overly simplistic and miss key subjective components of participationTaking a multidimensional perspective, we documented four meaningfully distinct participation subgroups (including both objective and subjective dimensions of societal participation) within the TBI rehabilitation populationMultidimensional profiles of participation may be used to group individuals with TBI into target groups for intervention (e.g., deeper goal assessment for individuals who do not rate standard participation activities as important, but also do not participate and do not feel enfranchised).

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.

Traumatic brain injury as a chronic disease: insights from the United States Traumatic Brain Injury Model Systems Research Program.

Traumatic brain injury (TBI) is a global health priority, associated with substantial burden. Historically conceptualised as an injury event with finite recovery, TBI is now recognised as a chronic condition that can affect multiple domains of health and function, some of which might deteriorate over time. Many people who have had a TBI remain moderately to severely disabled at 5 years, are rehospitalised up to 10 years post-injury, and have a reduced lifespan relative to the general population. Understanding TBI as a chronic disease process can be highly informative for optimising care, which has traditionally focused on acute care. Chronic brain injury care models must be informed by a holistic understanding of long-term outcomes and the factors that can affect how care needs evolve over time. The United States Traumatic Brain Injury Model Systems of Care follows up individuals with moderate-to-severe TBI for over 30 years, allowing characterisation of the chronic (2-30 years or more post injury) functional, cognitive, behavioural, and social sequelae experienced by individuals who have had a moderate-to-severe TBI and the implications for their health and quality of life. Older age, social determinants of health, and lower acute functional status are associated with post-recovery deterioration, while younger age and greater functional independence are associated with risky health behaviours, including substance misuse and re-injury. Systematically collected data on long-term outcomes across multiple domains of health and function are needed worldwide to inform the development of models for chronic disease management, including the proactive surveillance of commonly experienced health and functional challenges.

Effects of Perceived Discrimination on Behavioral Health Outcomes in People Aging With Traumatic Brain Injury.

OBJECTIVE: To evaluate major and everyday experiences of discrimination (MED and EED, respectively) in relation to behavioral health outcomes in people with traumatic brain injury (PwTBI). SETTING: Outpatient research laboratory. PARTICIPANTS: Adults, 50 years or older, with a chronic (1+ year) history of moderate or severe TBI ( N = 118). DESIGN: Cross-sectional observational study. MAIN MEASURES: MED and EED (primary measures of interest) and behavioral health outcomes: global cognition, psychological symptoms, neurobehavioral symptoms, societal participation, and health-related quality of life (HRQoL). In participants with available geodata ( N = 28), neighborhood socioeconomic deprivation (ND) was examined as a potential contributor to MED, EED, and measured outcomes. RESULTS: EED and MED were significantly associated with psychological symptoms, neurobehavioral symptoms, and HRQoL after correction for multiple comparisons. Counter to expectations, EED were related to higher societal participation. MED and EED were unrelated to cognition. When MED and EED were entered together in hierarchical regressions, only EED made significant contributions beyond demographic and injury-related covariates to each outcome. Sensitivity analyses revealed that most of these relationships were not solely accounted for by disability-related discrimination. ND showed negligible associations with discrimination but moderate effect sizes for cognition and participation. Race was not significantly related to discrimination and was not a significant predictor in regression models but was strongly associated with ND. CONCLUSION: The current data provide preliminary support for perceived discrimination as an important factor in neurobehavioral and psychosocial health, but not cognitive performance, after TBI. These relationships appear to be driven by daily experiences of discriminatory treatment versus single major instances of injustice. Measured outcomes may also reflect socioeconomic challenges and structural discrimination faced by diverse PwTBI, although more work in this area is urgently needed. Multiple sources of marginalization and disenfranchisement and their functional effects should be considered in TBI rehabilitation and outcome monitoring.

Societal Participation of People With Traumatic Brain Injury Before and During the COVID-19 Pandemic: A NIDILRR Traumatic Brain Injury Model Systems Study.

OBJECTIVE: To examine the effect of the COVID-19 pandemic on societal participation in people with moderate-to-severe traumatic brain injury (TBI). DESIGN: Cross-sectional retrospective cohort. SETTING: National TBI Model Systems centers, United States. PARTICIPANTS: TBI Model Systems enrollees (N=7003), ages 16 and older and 1-30 years postinjury, interviewed either prepandemic (PP) or during the pandemic (DP). The sample was primarily male (72.4%) and White (69.5%), with motor vehicle collisions as the most common cause of injury (55.1%). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURE: The 3 subscales of the Participation Assessment with Recombined Tools-Objective: Out and About (community involvement), Productivity, and Social Relations. RESULTS: Out and About, but not Productivity or Social Relations, scores were appreciably lower among DP participants compared to PP participants (medium effect). Demographic and clinical characteristics showed similar patterns of association with participation domains across PP and DP. When their unique contributions were examined in regression models, age, self-identified race, education level, employment status, marital status, income level, disability severity, and life satisfaction were variably predictive of participation domains, though most effects were small or medium in size. Depression and anxiety symptom severities each showed small zero-order correlations with participation domains across PP and DP but had negligible effects in regression analyses. CONCLUSIONS: Consistent with the effect of COVID-19 on participation levels in the general population, people with TBI reported less community involvement during the pandemic, potentially compounding existing postinjury challenges to societal integration. The pandemic does not appear to have altered patterns of association between demographic/clinical characteristics and participation. Assessing and addressing barriers to community involvement should be a priority for TBI treatment providers. Longitudinal studies of TBI that consider pandemic-related effects on participation and other societally linked outcomes will help to elucidate the potential longer-term effect the pandemic has on behavioral health in this population.

Depression, Anxiety, and Suicidality in Individuals With Chronic Traumatic Brain Injury Before and During the COVID-19 Pandemic: A National Institute on Disability, Independent Living, and Rehabilitation Research Traumatic Brain Injury Model Systems Study.

OBJECTIVE: To examine the prevalence, severity, and correlates of depression, anxiety, and suicidal ideation in people with traumatic brain injury (TBI) assessed before and during the COVID-19 pandemic. DESIGN: Retrospective cohort study using data collected through the Traumatic Brain Injury Model Systems (TBIMS) network at 1, 2, 5, 10, 15, 20, 25, or 30 years post TBI. SETTING: United States-based TBIMS rehabilitation centers with telephone assessment of community residing participants. PARTICIPANTS: Adults (72.4% male; mean age, 47.2 years) who enrolled in the TBIMS National Database and completed mental health questionnaires prepandemic (January 1, 2017 to February 29, 2020; n=5000) or during pandemic (April 1, 2022 to June 30, 2021; n=2009) (N=7009). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Patient Health Questionnaire-9 and Generalized Anxiety Disorder-7 questionnaire. RESULTS: Separate linear and logistic regressions were constructed with demographic, psychosocial, injury-related, and functional characteristics, along with a binary indicator of COVID-19 pandemic period (prepandemic vs during pandemic), as predictors of mental health outcomes. No meaningful differences in depression, anxiety, or suicidal ideation were observed before vs during the COVID-19 pandemic. Correlations between predictors and mental health outcomes were similar before and during the pandemic. CONCLUSIONS: Contrary to our predictions, the prevalence, severity, and correlates of mental health conditions were similar before and during the COVID-19 pandemic. Results may reflect generalized resilience and are consistent with the most recent findings from the general population that indicate only small, transient increases in psychological distress associated with the pandemic. While unworsened, depression, anxiety, and suicidal ideation remain prevalent and merit focused treatment and research efforts.

Using Machine Learning to Examine Suicidal Ideation After Traumatic Brain Injury: A Traumatic Brain Injury Model Systems National Database Study.

OBJECTIVE: The aim of the study was to predict suicidal ideation 1 yr after moderate to severe traumatic brain injury. DESIGN: This study used a cross-sectional design with data collected through the prospective, longitudinal Traumatic Brain Injury Model Systems network at hospitalization and 1 yr after injury. Participants who completed the Patient Health Questionnaire-9 suicide item at year 1 follow-up ( N = 4328) were included. RESULTS: A gradient boosting machine algorithm demonstrated the best performance in predicting suicidal ideation 1 yr after traumatic brain injury. Predictors were Patient Health Questionnaire-9 items (except suicidality), Generalized Anxiety Disorder-7 items, and a measure of heavy drinking. Results of the 10-fold cross-validation gradient boosting machine analysis indicated excellent classification performance with an area under the curve of 0.882. Sensitivity was 0.85 and specificity was 0.77. Accuracy was 0.78 (95% confidence interval, 0.77-0.79). Feature importance analyses revealed that depressed mood and guilt were the most important predictors of suicidal ideation, followed by anhedonia, concentration difficulties, and psychomotor disturbance. CONCLUSIONS: Overall, depression symptoms were most predictive of suicidal ideation. Despite the limited clinical impact of the present findings, machine learning has potential to improve prediction of suicidal behavior, leveraging electronic health record data, to identify individuals at greatest risk, thereby facilitating intervention and optimization of long-term outcomes after traumatic brain injury.

The Power of Perception: Beliefs About Memory Ability Uniquely Contribute to Memory Performance and Quality of Life in Adults Aging with Traumatic Brain Injury.

OBJECTIVE: Personal beliefs about memory ability, which comprise memory self-efficacy (MSE), can influence memory performance in healthy older adults. Self-efficacy theory also predicts that MSE biases self-perceptions of functioning more globally, potentially impacting daily activity beyond cognitive performance. People with traumatic brain injury (PwTBI) frequently report debilitating memory problems long after acute recovery, but little is known about how MSE affects health outcomes in this population. We examined demographic and clinical correlates of MSE, as well as its relationship to memory test performance and health-related quality of life (QOL), in older adults with chronic moderate-to-severe TBI (msTBI). METHOD: One hundred fourteen adults, aged 50+ and at least 1 year post-msTBI, underwent neuropsychological testing to assess their memory functioning. Participants also self-reported levels of psychological distress, MSE (Cognitive Confidence subscale of the Metacognitions Questionnaire), and health-related QOL (Quality of Life after Brain Injury questionnaire). RESULTS: Demographic and injury-related predictors showed weak correlations with MSE. Although the relationship between MSE and general psychological distress was robust, only the former significantly predicted memory performance. Bivariate analyses revealed significant relationships between MSE and five out of the six QOL domains assessed. Multivariate linear regression revealed a significant impact of MSE on overall QOL independent of demographic and clinical variables. CONCLUSIONS: Our findings support a unique role for MSE in both the objective cognitive performance and subjective health of PwTBI. Increased focus on self-perceptions of ability and their impact on measured outcomes is an important step towards personalized rehabilitation for adults with chronic msTBI.

Anxiety Trajectories the First 10 Years After a Traumatic Brain Injury (TBI): A TBI Model Systems Study.

OBJECTIVE: Determine anxiety trajectories and predictors up to 10 years posttraumatic brain injury (TBI). DESIGN: Prospective longitudinal, observational study. SETTING: Inpatient rehabilitation centers. PARTICIPANTS: 2836 participants with moderate to severe TBI enrolled in the TBI Model Systems National Database who had ≥2 anxiety data collection points (N=2836). MAIN OUTCOME MEASURE: Generalized Anxiety Disorder-7 (GAD-7) at 1, 2, 5, and 10-year follow-ups. RESULTS: Linear mixed models showed higher GAD-7 scores were associated with Black race (P<.001), public insurance (P<.001), pre-injury mental health treatment (P<.001), 2 additional TBIs with loss of consciousness (P=.003), violent injury (P=.047), and more years post-TBI (P=.023). An interaction between follow-up year and age was also related to GAD-7 scores (P=.006). A latent class mixed model identified 3 anxiety trajectories: low-stable (n=2195), high-increasing (n=289), and high-decreasing (n=352). The high-increasing and high-decreasing groups had mild or higher GAD-7 scores up to 10 years. Compared to the low-stable group, the high-decreasing group was more likely to be Black (OR=2.25), have public insurance (OR=2.13), have had pre-injury mental health treatment (OR=1.77), and have had 2 prior TBIs (OR=3.16). CONCLUSIONS: A substantial minority of participants had anxiety symptoms that either increased (10%) or decreased (13%) over 10 years but never decreased below mild anxiety. Risk factors of anxiety included indicators of socioeconomic disadvantage (public insurance) and racial inequities (Black race) as well as having had pre-injury mental health treatment and 2 prior TBIs. Awareness of these risk factors may lead to identifying and proactively referring susceptible individuals to mental health services.

Using Large-Scale Sensor Data to Test Factors Predictive of Perseverance in Home Movement Rehabilitation: Optimal Challenge and Steady Engagement.

Persevering with home rehabilitation exercise is a struggle for millions of people in the US each year. A key factor that may influence motivation to engage with rehabilitation exercise is the challenge level of the assigned exercises, but this hypothesis is currently supported only by subjective, self-report. Here, we studied the relationship between challenge level and perseverance using long-term, self-determined exercise patterns of a large number of individuals (N = 2,581) engaging in home rehabilitation with a sensor-based exercise system without formal supervision. FitMi is comprised of two puck-like sensors and a library of 40 gamified exercises for the hands, arms, trunk, and legs that are designed for people recovering from a stroke. We found that individuals showed the greatest perseverance with the system over a 2-month period if they had (1) a moderate level of motor impairment and (2) high but not perfect success during the 1st week at completing the exercise game. Further, a steady usage pattern (vs. accelerating or decelerating use) was associated with more overall exercise, and declines in exercise amount over time were associated with exponentially declining session initiation probability rather than decreasing amounts of exercise once a session was initiated. These findings confirm that an optimized challenge level and regular initiation of exercise sessions predict achievement of a greater amount of overall rehabilitation exercise in a group of users of commercial home rehabilitation technology and suggest how home rehabilitation programs and exercise technologies can be optimized to promote perseverance.

Development of RehaBot-A Conversational Agent for Promoting Rewarding Activities in Users With Traumatic Brain Injury.

OBJECTIVE: In this article, we describe the development and preliminary testing of RehaBot-a chatbot that users communicate with via text messaging designed to augment behavioral activation (BA) treatment of reducing depression and increasing participation in individuals with moderate to severe traumatic brain injury (TBI). SETTING: Outpatient brain injury rehabilitation facility. PARTICIPANTS: Outpatient brain injury clinicians and individuals with moderate to severe TBI. DESIGN: Focus groups, software demonstration trials, and single-case experiments with an A-B-A design. MAIN MEASURES: System Usability Scale (SUS) and self-reported completed target activities. RESULTS: Focus group feedback guided the development of a flexible system to be used in conjunction with face-to-face therapy, designed to provide reminders, encouragement, and supportive feedback. Two of 3 participants completed all 6 RehaBot tasks independently. One completed 4 tasks independently and a fifth with assistance. Average SUS score in demonstration trials was 76.77 (SD = 21.19). In 4 single-case experiments, participants completed their highest proportion of planned activities in the RehaBot phase and the lowest proportion of planned activities in the reversal phase. They all interacted with RehaBot daily, exchanging an average of 225 messages over the 1-week period, and average SUS score was 95 (SD = 4.74). Their open-ended feedback revealed that participants found RehaBot enjoyable and easy to use. They felt it was a helpful memory aid and promoted better adherence to planned activities by providing accountability and positive reinforcement. CONCLUSIONS: This article presents a chatbot development process heavily involving consumer input, which may serve as a model for future development efforts. Our findings provide preliminary evidence suggesting that RehaBot is usable and may promote better adherence to planned target activities. However, future research is needed to establish usability and efficacy of RehaBot and to explore applications of chatbots to other domains of TBI rehabilitation.

Relations Among Suicidal Ideation, Depressive Symptoms, and Functional Independence During the 10 Years After Traumatic Brain Injury: A Model Systems Study.

OBJECTIVE: To investigate relative causality in relations among suicidal ideation (SI), depressive symptoms, and functional independence over the first 10 years after traumatic brain injury (TBI). DESIGN: Prospective longitudinal design with data collected through the Traumatic Brain Injury Model Systems (TBIMS) network at acute rehabilitation hospitalization as well as 1, 2, 5, and 10 years after injury. SETTING: United States Level I/II trauma centers and inpatient rehabilitation centers with telephone follow-up. PARTICIPANTS: Individuals enrolled into the TBIMS National Database (N=9539) with at least 1 SI score at any follow-up data collection (72.1% male; mean age, 39.39y). INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Patient Health Questionnaire-9 and FIM at years 1, 2, 5, and 10 post injury. RESULTS: A cross-lagged panel structural equation model, which is meant to indirectly infer causality through longitudinal correlational data, suggested that SI, depressive symptoms, and functional independence each significantly predicted themselves over time. Within the model, bivariate correlations among variables were all significant within each time point. Between years 1 and 2 and between years 2 and 5, depressive symptoms had a larger effect on SI than SI had on depressive symptoms. Between years 5 and 10, there was reciprocal causality between the 2 variables. Functional independence more strongly predicted depressive symptoms than the reverse between years 1 and 2 as well as years 2 and 5, but its unique effects on SI over time were extremely marginal or absent after controlling for depressive symptoms. CONCLUSIONS: A primary goal for rehabilitation and mental health providers should be to monitor and address elevated symptoms of depression as quickly as possible before they translate into SI, particularly for individuals with TBI who have reduced functional independence. Doing so may be a key to breaking the connection between low functional independence and SI.

Cognitive Reserve in Individuals Aging With Traumatic Brain Injury: Independent and Interactive Effects on Cognitive Functioning.

OBJECTIVE: To examine the influence of 2 temporal factors-age and injury chronicity-on the relationship between cognitive reserve (CR) and cognitive functioning in older adults with chronic traumatic brain injury (TBI). SETTING: Outpatient research laboratory. PARTICIPANTS: Adults, 50 years or older, with a 1- to 45-year history of moderate or severe TBI (N = 108). DESIGN: Cross-sectional observational study. MAIN MEASURES: CR was estimated using demographically corrected performance on a word-reading test (an approximation of premorbid IQ). Injury chronicity was operationalized as number of years since the date of injury. Composite cognitive scores were computed from performances on neuropsychological tests of processing speed, executive functioning, and memory. RESULTS: CR was positively and significantly related to all cognitive performances independent of age, injury chronicity, and injury severity. Greater injury chronicity significantly attenuated the effect of CR on processing speed such that individuals more distal from their injury date evidenced a weaker positive relationship between CR and performance. CONCLUSION: Temporal factors may modify associations between CR and cognition. Findings suggest that the protective effects of CR are temporally delimited, potentially contending with declines in brain reserve. The prognostic value of traditional outcome determinants should be considered in the context of injury chronicity.

Identifying group-based patterns of suicidal ideation over the first 10 years after moderate-to-severe TBI.

OBJECTIVE: To identify group-based patterns in suicidal ideation (SI) over the first 10 years after traumatic brain injury (TBI). METHODS: Participants included 9539 individuals in the TBI Model Systems National Database who responded to Patient Health Questionnaire-9 Item 9 assessing SI at 1, 2, 5, and/or 10 years post-injury. A k-means cluster analysis was conducted to determine group-based patterns of SI, and pre-injury variables were compared with ANOVAs and chi-square tests. RESULTS: SI and attempts decreased over time. Four group-based patterns emerged: Low, increasing, moderate, and decreasing SI. The low SI group comprised 89% of the sample, had the highest pre-injury employment, fewer mental health vulnerabilities, least severe injuries, and were oldest. The increasing SI group had the most severe TBIs, were youngest, and disproportionately Black or Asian/Pacific Islander. CONCLUSION: These findings reinforce the importance of mental health and suicide risk assessment during chronic recovery from TBI.