Blast-related mild TBI: LIMBIC-CENC focused review with implications commentary.

BACKGROUND: A significant factor for the high prevalence of traumatic brain injury (TBI) among U.S. service members is their exposure to explosive munitions leading to blast-related TBI. Our understanding of the specific clinical effects of mild TBI having a component of blast mechanism remains limited compared to pure blunt mechanisms. OBJECTIVE: The purpose of this review is to provide a synopsis of clinical research findings on the long-term effects of blast-related mild TBI derived to date from the Long-Term Impact of Military-Relevant Brain Injury Consortium - Chronic Effects of Neurotrauma Consortium (LIMBIC-CENC). METHODS: Publications on blast-related mild TBI from LIMBIC-CENC and the LIMBIC-CENC prospective longitudinal study (PLS) cohort were reviewed and their findings summarized. Findings from the broader literature on blast-related mild TBI that evaluate similar outcomes are additionally reviewed for a perspective on the state of the literature. RESULTS: The most consistent and compelling evidence for long-term effects of blast-related TBI is for poorer psychological health, greater healthcare utilization and disability levels, neuroimaging impacts on brain structure and function, and greater headache impact on daily life. To date, evidence for chronic cognitive performance deficits from blast-related mild TBI is limited, but futher research including crucial longitudinal data is needed. CONCLUSION: Commentary is provided on: how LIMBIC-CENC findings assimilate with the broader literature; ongoing research gaps alongside future research needs and priorities; how the scientific community can utilize the LIMBIC-CENC database for independent or collaborative research; and how the evidence from the clinical research should be assimilated into clinical practice.

Research Letter: Characterizing Lifetime Mild TBI Exposure Among Female and Male Military Service Members and Veterans in the LIMBIC-CENC Study.

OBJECTIVE: To (1) characterize lifetime mild traumatic brain injury (TBI) exposures among male and female US military service members and Veterans (SMVs) and (2) evaluate sex-related differences in mild TBI exposures. SETTING: Clinical research laboratory. PARTICIPANTS: Participants were enrolled in the ongoing Long-term Impact of Military-relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium (LIMBIC-CENC) Prospective Longitudinal Study. DESIGN: Cross-sectional. MAIN MEASURES: Lifetime history of mild TBI was measured via structured interview. All mild TBI characteristics were collected as part of this interview, including total lifetime number; environment (deployment vs. non-deployment); timing of injury (relative to military service and age); and mechanism of injury (blast-related vs. non-blast). RESULTS: Most participants (n = 2323; 87.5% male; 79.6% Veteran) reported ≥1 lifetime mild TBI (n = 1912; 82%), among whom, many reported ≥2 lifetime mild TBIs. Female SMVs reported fewer total lifetime mild TBIs than male participants (P < 0.001), including fewer deployment-related (P < 0.001) and non-deployment (P < 0.001) mild TBIs. There were significant sex differences for total number of mild TBIs sustained before (P = 0.005) and during (P < 0.001) military service but not after separation from military service (P = 0.99). Among participants with a lifetime history of mild TBI, female SMVs were less likely to report ≥2 mTBIs (P = 0.003); however, male SMVs were more likely to report a mild TBI during military service (P = 0.03), including combat-related mild TBI (P < 0.001) and mild TBI involving blast (P < 0.001). CONCLUSIONS: These findings inform clinical and research efforts related to mild TBI in US military SMVs. It may not be sufficient to simply measure the total number of mild TBIs when seeking to compare clinical outcomes related to mild TBI between sexes; rather, it is important to measure and account for the timing, environment, and mechanisms associated with mild TBIs sustained by female and male SMVs.

More Than Skin Deep: Patient-Provider Racial and Ethnic Concordance and Discordance in Collegiate Athletics and Concussion Management.

CONTEXT: There is strong evidence that racial and ethnic disparities exist in multiple arenas of health and wellness. The causes of racial and ethnic differences in health care are multidimensional; one factor that may affect injury/illness communication, interactions, and outcomes is patient-provider racial and ethnic concordance. At present, it is unclear what role patient-provider racial and ethnic concordance and discordance plays in facilitating concussion care for collegiate athletes. OBJECTIVE: To investigate the presence of athlete-athletic trainer (AT) racial and ethnic concordance and discordance among diagnosed concussion cases and examine if racial and ethnic concordance and discordance influences time (in days) until diagnosis, symptom resolution, or return-to-sport clinical milestones in collegiate athletes. DESIGN: Retrospective cohort study. SETTING: Collegiate athletics. PATIENTS OR OTHER PARTICIPANTS: A total of 694 concussion cases (38.6% [n = 268] sustained by women, 61.4% [n = 426] sustained by men) that occurred within the 2015-2016 through 2019-2020 sport seasons at 9 institutions. MAIN OUTCOME MEASURE(S): The number of days from the date of injury to diagnosis, symptom resolution, and return to sport and from the date of diagnosis to symptom resolution and return to sport. RESULTS: Overall, 68.4% (n = 475) of concussion cases had patient-provider racial and ethnic concordance, and 31.6% (n = 219) were discordant. All concordant pairs included a White athlete and White AT. Time to diagnosis differed between the concordant and discordant groups (median [interquartile range] = 1 [0-2] versus 0 [0-1], respectively) only in the model adjusted for sex, sport type, and availability of an AT (odds ratio [95% CI] = 1.46 [1.07-1.85]). There were no other group differences. CONCLUSIONS: One-third of concussion cases had athlete-AT racial and ethnic discordance. Although this group was diagnosed with a concussion 1 day sooner than the concordant group, no differences were observed for any concussion recovery milestones. These findings suggest that patient-provider racial and ethnic concordance may play a minor role in concussion recognition or reporting but not necessarily in the management and recovery thereafter.

Longitudinal Characterization of Pain Interference and Influential Factors in Former National Football League (NFL) Players Over a 19-Year Period: An NFL-LONG Study.

Previous studies on pain experiences in retired contract sport athletes have been cross-sectional, leaving gaps in our understanding of the evolution of pain interference (PI) and factors that influence trajectories decades after sport discontinuation. This study investigated the longitudinal course of PI in former male National Football League (NFL) players over a 19-year period following sport discontinuation and examined factors influencing overall levels and trajectories of PI. Former NFL players completed health surveys in 2001, 2010, and 2019, with PI ratings measured using the 36-Item Short Form Health Survey (2001 and 2010) and the Patient-Reported Outcomes Measurement Information System (2019). Unconditional latent growth curve models analyzed overall PI severity and trajectories. Conditional latent growth curve models explored the influence of musculoskeletal injuries, osteoarthritis (OA), and depression diagnosis on PI. Over 19 years (N = 338; mean age = 48.96 ± 9.35), PI significantly increased (slope = .179, P < .001; mean Patient-Reported Outcomes Measurement Information System PI t-scores 2001 = 54.19, 2010 = 54.64, 2019 = 57.38). Cumulative musculoskeletal injuries (B = .092, P < .001) and baseline depression diagnosis (B = 4.463, P < .001) were associated with overall PI levels but not change over time. OA was significantly associated with overall PI levels (B = 6.536, P < .001) and trajectory (B = -.253, P < .001); those endorsing OA in 2001 had lower PI increases over 19 years. The body region of injury and level of play during injuries mirrored overall injury effects. PI mildly increased over 19 years, with multiple factors independently influencing overall PI levels. Enhancing former contact sport athletes' daily functionality may be achieved through holistic biopsychosocial interventions addressing musculoskeletal injuries, OA, and depression. Future research should identify factors influencing elevated trajectories of long-term PI post-sport discontinuation. PERSPECTIVE: This study assessed PI in former NFL athletes over 2 decades, revealing notable interindividual variability in trajectories over time. Musculoskeletal injuries, depression, and OA correlated with overall PI. Prevention and intervention in these 3 areas present the potential to improve disruptions in daily living due to pain in former athletes.

Sex-Dependency of T Cell-Induced Salt-Sensitive Hypertension and Kidney Damage.

BACKGROUND: It is established that the immune system, namely T cells, plays a role in the development of hypertension and renal damage in male Dahl salt-sensitive (SS) rats, but far less is known about this relationship in females. Rats with genetically deleted T cells via CD247 gene mutation on the Dahl SS background (SSCD247-/-) were utilized to interrogate the effect of sex and T cells on salt sensitivity. METHODS: We assessed the hypertensive and kidney injury phenotypes in male versus female SS and SSCD247-/- rats challenged with 3 weeks of high salt (4.0% NaCl). Differences in T cell activation genes were examined in renal T cells from male and female SS rats, and a sex-specific adoptive transfer was performed by injecting male or female splenocytes into either male or female SSCD247-/- recipients to determine the potential contribution of T cell sex. RESULTS: The lack of functional T cells in SSCD247-/- rats significantly reduced salt-induced hypertension and proteinuria in both sexes, although SSCD247-/- females exhibited greater protection from kidney damage. Adoptive transfer of either Dahl SS male or female splenocytes into SSCD247-/- male recipients exacerbated hypertension and proteinuria compared with controls, while in SSCD247-/- female recipients, exacerbation of disease occurred only upon transfer of male, but not female, SS splenocytes. CONCLUSIONS: The absence of T cells in the SSCD247-/- normalized sex differences in blood pressure, though sex differences in renal damage persisted. Splenocyte transfer experiments demonstrated that salt sensitivity is amplified if the sex of the T cell or the recipient is male.

Influence of sleep symptoms on recovery from concussion in collegiate athletes: a LIMBIC MATARS consortium investigation.

OBJECTIVE: Changes in sleep quality and quantity are commonly endorsed by individuals following a concussion. Limited data exists examining the role of sleep disturbances within 72 hours, and throughout recovery, from concussion. The objective of this study was to determine if the number of days to symptom resolution varied between collegiate athletes with or without sleep-related symptoms following a concussion. DESIGN: Retrospective chart review. METHODS: Collegiate athletes (n = 539) who were diagnosed with a concussion between the 2015-2020 sport seasons participated in this retrospective chart review. Participants were divided into groups based on the presence or absence of sleep symptoms within 72 hours of a diagnosed concussion. A Mann-Whitney U test was used to compare days to symptom resolution between groups with α = 0.05. RESULTS: Of the 539 participants, 250 (46.3%) reported sleep-related symptoms. Participants with sleep-related symptoms took significantly longer (U = 30656, p = 0.002) to report symptom resolution at rest (median [full range] = 8.00[0-423]) as compared to participants who did not report sleep-related symptoms (6.00[0-243] days). CONCLUSION: Collegiate athletes that report sleep-related symptoms immediately following concussion (<72 hours) were observed to take, on median, two days longer to achieve symptom resolution at rest when compared to athletes who did not endorse the same symptoms.

Physical activity and recovery following concussion in collegiate athletes: a LIMBIC MATARS Consortium Investigation.

OBJECTIVE: To investigate whether routine daily activities (RDA), non-prescribed exercise (Non-ERx), or prescribed exercise (ERx) were associated with recovery from sport-related concussion (SRC) in collegiate athletes. MATERIALS AND METHODS: Data for this cross-sectional, retrospective chart review of collegiate athletes diagnosed with SRC (n = 285[39.6% female], age = 19.5 ± 1.4 years) were collected during the 2015-16 to 2019-20 athletic seasons. The independent variable was group (RDA, Non-ERx, ERx). Dependent variables included days from date of diagnosis to symptom resolution (Dx-SR) and SR to return to sport (SR-RTS). RESULTS: Those in the Non-ERx group took nearly 1.3 times longer to achieve SR (IRR = 1.28, 95% CI: 1.11, 1.46) and, 1.8 times longer for RTS (IRR = 1.82, 95% CI: 1.11, 2.71) when compared to those in the RDA group. No other comparisons were significant. CONCLUSION: Collegiate athletes in the Non-ERx group took approximately 1 week longer to achieve SR as compared to the RDA and ERx groups. Our findings suggest that if exercise is recommended following SRC, it must be clearly and specifically prescribed. If exercise parameters cannot be prescribed, or monitored, RDA appear to be similarly beneficial during recovery for collegiate athletes with concussion.

Sport Type and Risk of Subsequent Injury in Collegiate Athletes Following Concussion: a LIMBIC MATARS Consortium Investigation.

OBJECTIVE: To investigate the association between sport type (collision, contact, non-contact) and subsequent injury risk following concussion in collegiate athletes. MATERIALS AND METHODS: This retrospective chart review of 248 collegiate athletes with diagnosed concussions (age: 20.0 ± 1.4 years; height: 179.6 ± 10.9 cm; mass: 79.0 ± 13.6 kg, 63% male) from NCAA athletic programs (n = 11) occurred between the 2015-2020 athletic seasons. Acute injuries that occurred within six months following concussion were evaluated. Subsequent injuries were grouped by lower extremity, upper extremity, trunk, or concussion. The independent variable was sport type: collision, contact, non-contact. A Cox proportional hazard model was used to assess the risk of subsequent injury between sport types. RESULTS: Approximately 28% (70/248) of athletes sustained a subsequent acute injury within six months post-concussion. Collision sport athletes had a significantly higher risk of sustaining any injury (HR: 0.41, p < 0.001, 95% CI: 0.28, 0.62), lower extremity (HR: 0.55, p = 0.04, 95% CI: 0.32, 0.97), and upper extremity (HR: 0.41, p = 0.01, 95% CI: 0.20, 0.81) injuries following concussion. No differences between sport types were observed for other injuries. CONCLUSION: Collision sport athletes had a higher rate of any subsequent injury, lower, and upper extremity injuries following concussion. Future research should focus on sport-specific secondary injury prevention efforts.

Access to athletic trainers and sex as modifiers of time to reach clinical milestones after sport-related concussion in collegiate athletes.

OBJECTIVE: Investigate whether an athlete's biological sex and exposure to a dedicated athletic trainer (AT) were related to clinical milestones after a sports-related concussion (SRC). DESIGN: Retrospective chart review. METHODS: Medical charts of collegiate athletes (n = 196 [70.9% female]) diagnosed with SRC were reviewed to extract: biological sex, dedicated AT exposure for their sport (yes/no), and time (days) to reaching clinical milestones (diagnosis, symptom resolution, unrestricted return to sport [RTS]). Mann-Whitney U tests were used to determine whether time to clinical milestones differed by sex, AT exposure, or their interaction. Proportions of same-day diagnoses and times to diagnosis, symptom resolution, and unrestricted RTS were evaluated with chi-squared and spearman's rank correlations, respectively. RESULTS: There were no significant differences in times to reaching any clinical milestone by sex, AT exposure, or their interaction (ps > 0.05). Forty-three percent of participants were diagnosed on the day of their SRC. This did not differ by sex or AT exposure (ps > 0.29). Longer times to SRC diagnosis were associated with more days to symptom resolution (ρ = 0.236, p = 0.001) and unrestricted RTS (ρ = 0.223, p < 0.001). CONCLUSIONS: Athlete sex and AT exposure were not associated with times to reach any clinical milestone; however, delayed diagnosis was associated with longer times to reach clinical recovery.

The Longitudinal Relationship Between Concussion History, Years of American Football Participation, and Alcohol Use Among Former National Football League Players: an NFL-LONG Study.

OBJECTIVE: Investigate the relationships between concussion history and years of football participation (repetitive head impact proxy) with alcohol use across multiple decades in former professional football players. METHODS: Participants (n = 348; mean age = 49.0 ± 9.4) completed health questionnaires in 2001 and 2019, which included self-reported concussion history and years of participation. Alcohol use frequency and amount per occasion were reported for three timepoints: during professional career, 2001, and 2019. Ordinal logistic regression models were fit to test associations of concussion history and years of participation with alcohol use at each timepoint. RESULTS: There were no significant associations between either concussion history or years of football participation with alcohol use (frequency and amount per occasion) at any timepoint. Effect estimates for concussion history and years of football participation with alcohol use were generally comparable across timepoints. CONCLUSIONS: Later life alcohol use by former American football players is not associated with concussion history or years of exposure to football.

Headache among combat-exposed veterans and service members and its relation to mild traumatic brain injury history and other factors: a LIMBIC-CENC study.

Background: Headache (HA) is a common persistent complaint following mild traumatic brain injury (mTBI), but the association with remote mTBI is not well established, and risk factors are understudied. Objective: Determine the relationship of mTBI history and other factors with HA prevalence and impact among combat-exposed current and former service members (SMs). Design: Secondary cross-sectional data analysis from the Long-Term Impact of Military-Relevant Brain Injury Consortium-Chronic Effects of Neurotrauma Consortium prospective longitudinal study. Methods: We examined the association of lifetime mTBI history, demographic, military, medical and psychosocial factors with (1) HA prevalence ("lately, have you experienced headaches?") using logistic regression and (2) HA burden via the Headache Impact Test-6 (HIT-6) using linear regression. Each lifetime mTBI was categorized by mechanism (blast-related or not) and setting (combat deployed or not). Participants with non-credible symptom reporting were excluded, leaving N = 1,685 of whom 81% had positive mTBI histories. Results: At a median 10 years since last mTBI, mTBI positive participants had higher HA prevalence (69% overall, 78% if 3 or more mTBIs) and greater HA burden (67% substantial/severe impact) than non-TBI controls (46% prevalence, 54% substantial/severe impact). In covariate-adjusted analysis, HA prevalence was higher with greater number of blast-related mTBIs (OR 1.81; 95% CI 1.48, 2.23), non-blast mTBIs while deployed (OR 1.42; 95% CI 1.14, 1.79), or non-blast mTBIs when not deployed (OR 1.23; 95% CI 1.02, 1.49). HA impact was only higher with blast-related mTBIs. Female identity, younger age, PTSD symptoms, and subjective sleep quality showed effects in both prevalence and impact models, with the largest mean HIT-6 elevation for PTSD symptoms. Additionally, combat deployment duration and depression symptoms were factors for HA prevalence, and Black race and Hispanic/Latino ethnicity were factors for HA impact. In sensitivity analyses, time since last mTBI and early HA onset were both non-significant. Conclusion: The prevalence of HA symptoms among formerly combat-deployed veterans and SMs is higher with more lifetime mTBIs regardless of how remote. Blast-related mTBI raises the risk the most and is uniquely associated with elevated HA burden. Other demographic and potentially modifiable risk factors were identified that may inform clinical care.

Mild traumatic brain injury history is associated with lower brain network resilience in soldiers.

Special Operations Forces combat soldiers sustain frequent blast and blunt neurotrauma, most often classified as mild traumatic brain injuries. Exposure to repetitive mild traumatic brain injuries is associated with persistent behavioural, cognitive, emotional and neurological symptoms later in life. Identifying neurophysiological changes associated with mild traumatic brain injury exposure, in the absence of present-day symptoms, is necessary for detecting future neurological risk. Advancements in graph theory and functional MRI have offered novel ways to analyse complex whole-brain network connectivity. Our purpose was to determine how mild traumatic brain injury history, lifetime incidence and recency affected whole-brain graph theoretical outcome measures. Healthy male Special Operations Forces combat soldiers (age = 33.2 ± 4.3 years) underwent multimodal neuroimaging at a biomedical research imaging centre using 3T Siemens Prisma or Biograph MRI scanners in this cross-sectional study. Anatomical and functional scans were preprocessed. The blood-oxygen-level-dependent signal was extracted from each functional MRI time series using the Big Brain 300 atlas. Correlations between atlas regions were calculated and Fisher z-transformed to generate subject-level correlation matrices. The Brain Connectivity Toolbox was used to obtain functional network measures for global efficiency (the average inverse shortest path length), local efficiency (the average global efficiency of each node and its neighbours), and assortativity coefficient (the correlation coefficient between the degrees of all nodes on two opposite ends of a link). General linear models were fit to compare mild traumatic brain injury lifetime incidence and recency. Nonparametric ANOVAs were used for tests on non-normally distributed data. Soldiers with a history of mild traumatic brain injury had significantly lower assortativity than those who did not self-report mild traumatic brain injury (t148 = 2.44, P = 0.016). The assortativity coefficient was significantly predicted by continuous mild traumatic brain injury lifetime incidence [F1,144 = 6.51, P = 0.012]. No differences were observed between recency groups, and no global or local efficiency differences were observed between mild traumatic brain injury history and lifetime incidence groups. Brain networks with greater assortativity have more resilient, interconnected hubs, while those with lower assortativity indicate widely distributed, vulnerable hubs. Greater lifetime mild traumatic brain injury incidence predicted lower assortativity in our study sample. Less resilient brain networks may represent a lack of physiological recovery in mild traumatic brain injury patients, who otherwise demonstrate clinical recovery, more vulnerability to future brain injury and increased risk for accelerated age-related neurodegenerative changes. Future longitudinal studies should investigate whether decreased brain network resilience may be a predictor for long-term neurological dysfunction.

Associations between health-related behaviors and self-reported cognitive symptoms in U.S. military personnel injured on deployment.

Health behaviors may be core contributors to cognition and mental health following mild traumatic brain injury (TBI). The aims of the present study examined: (1) whether health behaviors including sleep duration, alcohol use, and physical activity differed in injured military personnel with and without deployment-related mild TBI history and (2) the relative contributions of health behaviors and deployment-related mild TBI history to self-reported cognitive, posttraumatic stress disorder (PTSD), and depressive symptoms. Participants included 3076 military personnel injured on deployment participating in the Wounded Warrior Recovery Project, an ongoing web-based study. Military personnel with deployment-related mild TBI history reported similar rates of physical activity and levels of alcohol problems as those without, but were less likely to report receiving the recommended duration of sleep. When adjusting for demographic and injury variables, all three health behaviors were associated with cognitive, PTSD, and depressive symptoms. Alcohol problems demonstrated significant but small effects across all outcomes measures (ηp2=.01) whereas physical activity was associated with slightly larger effects albeit still within the small range (ηp2=.02-0.04). Duration of sleep bordered a medium effect for cognitive symptoms (ηp2=.05) and was in the medium range for PTSD and depressive symptoms (ηp2=.06). Although deployment-related mild TBI history was significant in all models, effect sizes were small (ηp2=.01). Findings from the present study provide support that health behaviors have stronger effects with regard to cognitive, PTSD, and depressive symptoms compared to deployment-related mild TBI history in military personnel and, given their modifiable nature, may represent treatment targets in this population.

Subjective and Performance-Based Cognition and Their Associations with Head Injury History in Older Former National Football League Players.

PURPOSE: Investigate the association between self-reported subjective and performance-based cognition among older (50-70 years) former professional American football players, as well as the relationship of cognitive measures with concussion history and years of football participation, as a proxy for repetitive head impact exposure. METHODS: Among older former National Football League (NFL) players ( N = 172; mean age = 60.69 ± 5.64), associations of subjective (Patient Reported Outcome Measurement Information System Cognitive Function-Short Form) and performance-based cognitive measures (Brief Test of Adult Cognition by Telephone [BTACT] Executive Function and Episodic Memory indices) were assessed via univariable and multivariable regression models, with a priori covariates of depression and race. A similar univariate and multivariable regression approach assessed associations between concussion history and years of football participation with subjective and performance-based cognitive measures. In a sample subset ( n = 114), stability of subjective cognitive rating was assessed via partial correlation. RESULTS: Subjective ratings of cognition were significantly associated with performance-based assessment, with moderate effect sizes (episodic memory ηp2 = 0.12; executive function ηp2 = 0.178). These associations were weakened, but remained significant ( P s < 0.05), with the inclusion of covariates. Greater concussion history was associated with lower subjective cognitive function ( ηp2 = 0.114, P < 0.001), but not performance-based cognition. The strength of association between concussion history and subjective cognition was substantially weakened with inclusion of covariates ( ηp2 = 0.057). Years of participation were not associated with measures of subjective or objective cognition ( P s > 0.05). CONCLUSIONS: These findings reinforce the importance of comprehensive evaluation reflecting both subjective and objective measures of cognition, as well as the consideration of patient-specific factors, as part of a comprehensive neurobehavioral and health assessment of older former contact sport athletes.

Functional NADPH oxidase 2 in T cells amplifies salt-sensitive hypertension and associated renal damage.

Infiltrating T cells in the kidney amplify salt-sensitive (SS) hypertension and renal damage, but the mechanisms are not known. Genetic deletion of T cells (SSCD247-/-) or of the p67phox subunit of NADPH oxidase 2 (NOX2; SSp67phox-/-) attenuates SS hypertension in the Dahl SS rat. We hypothesized that reactive oxygen species produced by NOX2 in T cells drive the SS phenotype and renal damage. T cells were reconstituted by adoptively transferring splenocytes (∼10 million) from the Dahl SS (SS→CD247) rat, the SSp67phox-/- rat (p67phox→CD247), or only PBS (PBS→CD247) into the SSCD247-/- rat on postnatal day 5. Animals were instrumented with radiotelemeters and studied at 8 wk of age. There were no detectable differences in mean arterial pressure (MAP) or albuminuria between groups when rats were maintained on a low-salt (0.4% NaCl) diet. After 21 days of high-salt diet (4.0% NaCl), MAP and albuminuria were significantly greater in SS→CD247 rats compared with p67phox→CD247 and PBS→CD247 rats. Interestingly, there was no difference between p67phox→CD247 and PBS→CD247 rats in albuminuria or MAP after 21 days. The lack of CD3+ cells in PBS→CD247 rats and the presence of CD3+ cells in rats that received the T cell transfer demonstrated the effectiveness of the adoptive transfer. No differences in the number of CD3+, CD4+, or CD8+ cells were observed in the kidneys of SS→CD247 and p67phox→CD247 rats. These results indicate that reactive oxygen species produced by NOX2 in T cells participates in the amplification of SS hypertension and renal damage.NEW & NOTEWORTHY Our current work used the adoptive transfer of T cells that lack functional NADPH oxidase 2 into a genetically T cell-deficient Dahl salt-sensitive (SS) rat model. The results demonstrated that reactive oxygen species produced by NADPH oxidase 2 in T cells participate in the amplification of SS hypertension and associated renal damage and identifies a potential mechanism that exacerbates the salt-sensitive phenotype.