Cognitive function 10 years after adolescent bariatric surgery.

BACKGROUND: Adolescent bariatric surgery produces substantial weight loss and reduction of medical co-morbidities. Research in adult samples shows improved cognitive function postoperatively, although much less is known about the potential cognitive benefits of bariatric surgery in adolescents-especially at extended follow-up. OBJECTIVE: Examine cognitive function 10 years after adolescent bariatric surgery. SETTING: University hospital. METHODS: A total of 99 young adults who underwent bariatric surgery as adolescents completed a computerized cognitive test battery as part of a larger 10-year postoperative assessment. All had been long-term participants in the Teen-Longitudinal Assessment of Bariatric Surgery (Teen-LABS) study. RESULTS: Cognitive dysfunction was prevalent on tests of attention and executive function (e.g., Continuous Performance Test - Reaction Time 30%; Maze Errors - Overrun 30%), and 53.5% met research criteria for mild cognitive impairment (MCI). Modified Poisson regression with robust error variance revealed participants with preoperative hypertension and those completing Roux-en-Y gastric bypass were more likely to meet criteria for MCI at 10-year follow-up. CONCLUSIONS: The current findings indicate that cognitive deficits are common 10 years after bariatric surgery. Additional studies are needed to clarify possible cohort effects, determine whether these cognitive deficits persist to even later follow-up (e.g., 20 yr after surgery), and identify underlying mechanisms and mitigation strategies.

Distinguishable features of spontaneous speech in Alzheimer's clinical syndrome and healthy controls.

There is growing evidence that subtle changes in spontaneous speech may reflect early pathological changes in cognitive function. Recent work has found that lexical-semantic features of spontaneous speech predict cognitive dysfunction in individuals with mild cognitive impairment (MCI). The current study assessed whether Ostrand and Gunstad's (OG) lexical-semantic features extend to predicting cognitive status in a sample of individuals with Alzheimer's clinical syndrome (ACS) and healthy controls. Four additional (New) speech indices shown to be important in language processing research were also explored in this sample to extend prior work. Speech transcripts of the Cookie Theft Task from 81 individuals with ACS (Mage = 72.7 years, SD = 8.80, 70.4% female) and 61 healthy controls (HC) (Mage = 63.9 years, SD = 8.52, 62.3% female) from Dementia Bank were analyzed. Random forest and logistic machine learning techniques examined whether subject-level lexical-semantic features could be used to accurately discriminate those with ACS from HC. Results showed that logistic models with the New lexical-semantic features obtained good classification accuracy (78.4%), but the OG features had wider success across machine learning model types. In terms of sensitivity and specificity, the random forest model trained on the OG features was the most balanced. Findings from the current study suggest that features of spontaneous speech used to predict MCI may also distinguish between individuals with ACS and healthy controls. Future work should evaluate these lexical-semantic features in pre-clinical persons to further explore their potential to assist with early detection through speech analysis.

Pain in the Context of Virtual Neuropsychological Assessment of Older Adults.

OBJECTIVE: Pain and cognitive impairment are prevalent and often co-occur in older adults. Because pain may negatively affect cognitive test performance, identification of pain in the context of neuropsychological evaluation is important. However, pain detection based on self-report presents challenges, and pain is often under-detected in this population. Alternative methods (e.g., video-based automatic coding of facial biomarkers of pain) may facilitate pain identification and thus enhance interpretation of neuropsychological evaluation results. METHOD: The current study examined pain in the context of virtual neuropsychological assessment in 111 community-dwelling older adults, first seeking to validate the use of software developed to automatically code biomarkers of pain. Measures of pain, including self-report of acute and chronic pain and automatic coding of pain, were compared while participants completed neuropsychological testing. RESULTS: Self-reported pain was negatively associated with poorer performance on a measure of executive function (both acute and chronic pain) and a global cognitive screening measure (acute pain only). However, self-reported acute and chronic pain did not correlate significantly with most neuropsychological tests. Automatic coding of pain did not predict self-report of pain or performance on neuropsychological tests beyond the influence of demographic factors and psychological symptoms. CONCLUSIONS: Though results were largely not significant, correlations warrant further exploration of the influence of pain on neuropsychological test performance in this context to ensure that pain does not influence test performance in individuals with higher levels of pain and in other samples.

Can the positive buffer the negative? Testing the impact of protective childhood experiences on adjustment in adults following trauma exposure.

BACKGROUND: It is unclear if protective childhood experiences (PCEs), like emotional support and economic stability, exert influence on adulthood adjustment. Prior research suggests PCEs can promote childhood resilience through increased social connection. In contrast, research has demonstrated potential life-long negative impacts of adverse childhood experiences (ACEs) on psychological health. This study examined the role of PCEs and ACEs in psychological symptoms following potentially traumatic events (PTE) in adults. METHODS: Participants (N = 128) were adults admitted to two Level 1 Trauma Centers following violence, motor-vehicle crashes, or other accidents. Participants reported childhood experiences and completed assessments of depression, PTSD, and social support at one, four, and nine months post-PTE. RESULTS: Structural Equation Modeling was used to simultaneously model PCEs and ACEs as predictors of psychological symptoms over time, with potential mediation through social support. PCEs overall did not directly affect psychological symptoms nor indirectly through social support. However, the emotional support component of PCEs had an indirect effect on psychological symptoms at baseline through social support. ACEs predicted greater psychological symptoms at baseline and over time. CONCLUSION: PCEs consisting of childhood emotional support indirectly promote adjustment in adults after PTEs through initial social support, while ACEs exert direct effects on psychological symptoms.

Lexical Speech Features of Spontaneous Speech in Older Persons With and Without Cognitive Impairment: Reliability Analysis.

Background: Speech analysis data are promising digital biomarkers for the early detection of Alzheimer disease. However, despite its importance, very few studies in this area have examined whether older adults produce spontaneous speech with characteristics that are sufficiently consistent to be used as proxy markers of cognitive status. Objective: This preliminary study seeks to investigate consistency across lexical characteristics of speech in older adults with and without cognitive impairment. Methods: A total of 39 older adults from a larger, ongoing study (age: mean 81.1, SD 5.9 years) were included. Participants completed neuropsychological testing and both picture description tasks and expository tasks to elicit speech. Participants with T-scores of ≤40 on ≥2 cognitive tests were categorized as having mild cognitive impairment (MCI). Speech features were computed automatically by using Python and the Natural Language Toolkit. Results: Reliability indices based on mean correlations for picture description tasks and expository tasks were similar in persons with and without MCI (with r ranging from 0.49 to 0.65 within tasks). Intraindividual variability was generally preserved across lexical speech features. Speech rate and filler rate were the most consistent indices for the cognitively intact group, and speech rate was the most consistent for the MCI group. Conclusions: Our findings suggest that automatically calculated lexical properties of speech are consistent in older adults with varying levels of cognitive impairment. These findings encourage further investigation of the utility of speech analysis and other digital biomarkers for monitoring cognitive status over time.

Application of the multiphase optimisation strategy (MOST) to optimise HIV prevention targeting people on medication for opioid use disorder (MOUD) who have cognitive dysfunction: protocol for a MOST study.

INTRODUCTION: People who inject drugs (PWID) have remained a contributor to the consistent HIV incidence rates in the US for decades. Pre-exposure prophylaxis (PrEP) is a promising biomedical intervention for HIV prevention among individuals at risk for HIV infection, including PWID. However, PWID report the lowest rates of PrEP uptake and adherence among at-risk groups. Tailored HIV prevention interventions must include strategies that compensate for cognitive dysfunction among PWID. METHODS AND ANALYSIS: Using the multiphase optimisation strategy, we will be conducting a 16-condition factorial experiment to investigate the effects of four different accommodation strategy components to compensate for cognitive dysfunction among 256 PWID on medication for opioid use disorder. This innovative approach will inform optimisation of a highly effective intervention to enhance PWID's ability to process and utilise HIV prevention content to improve PrEP adherence and HIV risk reduction in a drug treatment setting. ETHICS AND DISSEMINATION: The institutional review board at the University of Connecticut approved this protocol (H22-0122) with an institutional reliance agreement with APT Foundation Inc. All participants are required to sign an informed consent form prior to engaging in any study protocols. The results of this study will be disseminated on national and international platforms through presentations at major conferences and journals. TRIAL REGISTRATION NUMBER: NCT05669534.

Examining sex differences in the association between sedentary behavior and cognitive function in bariatric surgery patients.

BACKGROUND: Obesity is associated with cognitive impairment. A potential contributor to these deficits is sedentary behavior (SB), which is linked to poorer cognitive functioning in other populations. Little is known about the association between SB and cognitive function in bariatric surgery populations. OBJECTIVES: This cross-sectional study examined the association between SB and cognitive function in preoperative bariatric surgery patients, as well as possible sex differences in this relationship. SETTING: Data were collected at 2 health centers in the United States. METHODS: A total of 121 participants (43.2 ± 10.3 yr of age) scheduled for Roux-en-Y gastric bypass or sleeve gastrectomy completed the National Institute of Health (NIH) Toolbox for the Assessment of Neurological and Behavioral Function Cognition Domain, a computerized neuropsychological assessment battery. Participants wore a waist-mounted accelerometer for 7 consecutive days to measure SB and light-intensity physical activity (LPA). RESULTS: Pearson and partial correlations found no significant relationships between cognitive function and SB or LPA in the full sample. However, partial correlations controlling for LPA found that greater SB was associated with poorer performance on List Sorting Working Memory Test in women (r = -.28; P = .006), whereas there was a positive relationship between SB and Dimensional Change Card Sort for men (r = .51; P = .015; 95% CI [.25, .73]). CONCLUSIONS: These results showed that greater SB, independent of LPA, is associated with poorer working memory in women and better set shifting ability in men. Future studies should examine the possibility of domain-specific cognitive effects associated with SB in bariatric surgery samples and clarify possible sex differences.

Associations Between Changes in Activity and Dietary Behaviors after Metabolic and Bariatric Surgery.

INTRODUCTION: Patients who undergo metabolic and bariatric surgery (MBS) are advised to make healthy activity and dietary changes. While previous research has examined post-surgical changes in activity and dietary behaviors separately, no study has assessed whether changes in these behaviors are beneficially associated with each other. We evaluated whether post-surgical improvements in activity behaviors related to favorable changes in dietary behaviors overall and by surgery type (Roux-en-Y gastric bypass [RYGB], sleeve gastrectomy [SG]). METHODS: At pre-surgery and 6- and 12-months post-surgery, participants (N = 97; 67 RYGB/30 SG) wore an accelerometer for 7 days and completed 24-h dietary assessments on 3 days. General linear models assessed associations between pre- to post-surgical changes in activity (moderate-to-vigorous physical intensity activity [MVPA], sedentary time [ST]) and dietary (total energy intake [EI; kcal/day], dietary quality [healthy eating index/HEI scores]) behaviors, with surgery type as a moderator. RESULTS: Participants on average: demonstrated small, non-significant post-surgical changes in MVPA and ST minutes/day (ps > .05); and reported significant post-surgical decreases in EI (p < .001), but no changes in HEI scores (ps > .25). Greater 12-month post-surgical increases in MVPA were significantly associated with greater decreases in EI, but only for RYGB participants (p < .001). DISCUSSION: Participants reported large decreases in EI, but made minimal changes in other behaviors after MBS. Results suggest greater increases in MVPA could assist with achieving greater decreases in EI, although this benefit appears to be limited to RYGB patients. Additional research is needed to confirm these findings and determine whether activity-dietary behavior associations differ beyond the immediate post-surgical year.

Change in medial frontal cerebral metabolite concentrations following bariatric surgery.

Obesity is associated with adverse effects on brain health, including an increased risk of neurodegenerative diseases. Changes in cerebral metabolism may underlie or precede structural and functional brain changes. While bariatric surgery is known to be effective in inducing weight loss and improving obesity-related medical comorbidities, few studies have examined whether it may be able to improve brain metabolism. In the present study, we examined changes in cerebral metabolite concentrations in participants with obesity who underwent bariatric surgery. Thirty-five patients with obesity (body mass index ≥ 35 kg/m2 ) were recruited from a bariatric surgery candidate nutrition class. They completed single voxel proton magnetic resonance spectroscopy at baseline (presurgery) and within 1 year postsurgery. Spectra were obtained from a large medial frontal brain region using a PRESS sequence on a 3-T Siemens Verio scanner. The acquisition parameters were TR = 3000 ms and TE = 37 ms. Tissue-corrected metabolite concentrations were determined using Osprey. Paired t-tests were used to examine within-subject change in metabolite concentrations, and correlations were used to relate these changes to other health-related outcomes, including weight loss and glycated hemoglobin (HbA1c ), a measure of blood sugar levels. Bariatric surgery was associated with a reduction in cerebral choline-containing compounds (Cho; t [34] = - 3.79, p < 0.001, d = -0.64) and myo-inositol (mI; t [34] = - 2.81, p < 0.01, d = -0.47) concentrations. There were no significant changes in N-acetyl-aspartate, creatine, or glutamate and glutamine concentrations. Reductions in Cho were associated with greater weight loss (r = 0.40, p < 0.05), and reductions in mI were associated with greater reductions in HbA1c (r = 0.44, p < 0.05). In conclusion, participants who underwent bariatric surgery exhibited reductions in cerebral Cho and mI concentrations, which were associated with improvements in weight loss and glycemic control. Given that elevated levels of Cho and mI have been implicated in neuroinflammation, reduction in these metabolites after bariatric surgery may reflect amelioration of obesity-related neuroinflammatory processes. As such, our results provide evidence that bariatric surgery may improve brain health and metabolism in individuals with obesity.

Resting-state network functional connectivity before and after bariatric surgery.

BACKGROUND: Bariatric surgery is an increasingly popular treatment for patients with severe obesity and related health issues (e.g., diabetes, cardiovascular disease). Studies have identified alterations in functional connectivity both in obesity and following surgical treatment for severe obesity. OBJECTIVE: This study aimed to assess brain function via resting-state within-network connectivity in bariatric surgery patients with severe obesity. SETTING: University hospital. METHODS: Thirty-four bariatric surgery patients completed functional neuroimaging at baseline and postoperatively (goal, 12 weeks; actual, 16 weeks, on average). They also self-reported health information. Baseline resting-state functional connectivity (RSFC) was predicted by baseline age, body mass index (BMI), continuous positive airway pressure use, and reported history of rheumatoid arthritis and type 2 diabetes. Change in RSFC was assessed using the same predictors. This model was run with and without controlling for baseline RSFC. RESULTS: Higher baseline BMI predicted lower baseline RSFC in 3 networks. Lower baseline RSFC also was related to rheumatoid arthritis and type 2 diabetes. Difference between baseline and follow-up RSFC was strongly negatively associated with baseline RSFC. Controlling for baseline RSFC, type 2 diabetes negatively predicted RSFC difference. CONCLUSIONS: RSFC may reflect brain dysfunction in patients with obesity and related diseases. That less connectivity at baseline predicted greater positive change suggests that RSFC may be a biomarker of neurocognitive improvement following bariatric surgery. Diseases more prevalent in patients with obesity (e.g., rheumatoid arthritis and type 2 diabetes) along with elevated BMI negatively affect RSFC likely through inflammatory pathways.

Deficits in cognitive control during alcohol consumption after bariatric surgery.

BACKGROUND: While bariatric surgery results in substantial weight loss, one negative side effect of surgery is that patients often experience more rapid and intense intoxication effects after consuming alcohol. OBJECTIVES: Given that alcohol use has been associated with impaired cognitive functioning in the general population, this study examined whether acute alcohol consumption after bariatric surgery immediately led to impaired cognitive control, and whether this effect was impacted by baseline levels of cognitive control. SETTING: Nonprofit teaching hospital, United States. METHODS: Participants were 34 adults who attended a laboratory visit before and 1 year after Roux-en-Y gastric bypass surgery, wherein they consumed a weight-based dose of alcohol and completed cognitive testing over the course of 3 hours. RESULTS: A series of generalized mixed-effect models demonstrated that performance on the cognitive task generally improved over time, likely due to practice effects. However, following bariatric surgery, individuals with impaired cognitive control before consuming alcohol experienced greater commission errors immediately afterward. CONCLUSIONS: These findings suggest that alcohol use after bariatric surgery may produce immediate deficits in inhibitory control among individuals who are already vulnerable to impaired cognitive control. Clinicians should seek to educate bariatric surgery candidates on this possible effect, as deficits in inhibitory control may ultimately lead to risky behaviors and poor adherence with postsurgical medical recommendations.

Poorer Cognitive Performance Is Associated with Gastrointestinal Symptoms in Otherwise Healthy Young Adults.

INTRODUCTION: Functional gastrointestinal disorders such as irritable bowel syndrome are often associated with abdominal discomfort, bloating, and cramping. There is growing evidence that gastrointestinal symptoms are also related to cognitive function, but this association has not been previously examined in young adults. METHODS: We examined cross-sectional relationships between nonspecific gastrointestinal symptoms and cognition in 56 healthy young adults (41 female, 15 male) without diagnosis of gastrointestinal disorder. RESULTS: Gastrointestinal symptoms were associated with poorer performance on objective tests of memory (p < 0.01 for all) and greater self-report of cognitive dysfunction (p < 0.01 for all). CONCLUSION: Results suggest that higher gastrointestinal symptoms are associated with greater subjective and objective cognitive difficulty. Future work is needed to clarify underlying mechanisms and the potential functional impact of these cognitive deficits.

Considerations regarding noncredible performance in the neuropsychological assessment of patients with multiple sclerosis: A case series.

Determining the validity of data during clinical neuropsychological assessment is crucial for proper interpretation, and extensive literature has emphasized myriad methods of doing so in diverse samples. However, little research has considered noncredible presentation in persons with multiple sclerosis (pwMS). PwMS often experience one or more factors known to impact validity of data, including major neurocognitive impairment, psychological distress/psychogenic interference, and secondary gain. This case series aimed to illustrate the potential relationships between these factors and performance validity testing in pwMS. Six cases from an IRB-approved database containing pwMS referred for neuropsychological assessment at a large, academic medical center involving at least one of the above-stated factors were identified. Backgrounds, neuropsychological test data, and clinical considerations for each were reviewed. Interestingly, no pwMS diagnosed with major neurocognitive impairment was found to have noncredible performance, nor was any patient with noncredible performance in the absence of notable psychological distress. Given the variability of noncredible performance and multiplicity of factors affecting performance validity in pwMS, clinicians are strongly encouraged to consider psychometrically appropriate methods for evaluating validity of cognitive data in pwMS. Additional research aiming to elucidate base rates of, mechanisms begetting, and methods for assessing noncredible performance in pwMS is imperative.

Latent profile analysis of data from the brief inventory of neurocognitive impairment (BINI) to develop neuro-cognitive profiles among opioid-dependent patients in drug treatment.

BACKGROUND: Neurocognitive dysfunction is common among individuals with opioid use disorders (OUD) and can impede a range of treatment outcomes. We developed the 57-item Brief Inventory of Neuro-cognitive Impairment (BINI) to help detect and monitor neurocognitive dysfunction in the context of drug treatment settings. To date, no study has examined the possible presence of BINI subgroups among OUD patients, which could enhance our ability to tailor intervention strategies to meet individual treatment needs. The purpose of this study was to conduct a latent profile analysis to identify BINI subgroups that differ in terms of their reported and objective neurocognitive dysfunction. We hypothesized that subgroups would emerge, suggesting the potential benefit of implementing tailored strategies for optimal treatment outcomes. METHODS: Latent profile analyses included data from opioid-dependent patients (N = 177) enrolled in a methadone maintenance treatment program between July 2018 and October 2019. RESULTS: We found three profiles of self-reported neurocognitive symptoms, including those with 1) minimal concerns 2) moderate concerns, and 3) many concerns across multiple domains. CONCLUSIONS: If these results are confirmed, the BINI may be used to rapidly identify persons who require specific accommodation strategies to improve their drug treatment outcomes.

The gut microbiome, mild cognitive impairment, and probiotics: A randomized clinical trial in middle-aged and older adults.

BACKGROUND: Advancing age coincides with changes in the gut microbiome and a decline in cognitive ability. Psychobiotics are microbiota-targeted interventions that can result in mental health benefits and protect the aging brain. This study investigated the gut microbiome composition and predicted microbial functional pathways of middle-aged and older adults that met criteria for mild cognitive impairment (MCI), compared to neurologically healthy individuals, and investigated the impact of probiotic Lactobacillus rhamnosus GG (LGG) in a double-blind, placebo-controlled, randomized clinical trial. A total of 169 community-dwelling middle-aged (52-59 years) and older adults (60-75 years) received a three-month intervention and were randomized to probiotic and placebo groups. Participants were further subdivided based on cognitive status into groups with intact or impaired cognition and samples were collected at baseline and post supplementation. RESULTS: Microbiome analysis identified Prevotella ruminicola, Bacteroides thetaiotaomicron, and Bacteroides xylanisolvens as taxa correlated with MCI. Differential abundance analysis at baseline identified Prevotella as significantly more prevalent in MCI subjects compared to cognitively intact subjects (ALDEx2 P = 0.0017, ANCOM-BC P = 0.0004). A decrease in the relative abundance of the genus Prevotella and Dehalobacterium in response to LGG supplementation in the MCI group was correlated with an improved cognitive score. CONCLUSIONS: Our study points to specific members of the gut microbiota correlated with cognitive performance in middle-aged and older adults. Should findings be replicated, these taxa could be used as key early indicators of MCI and manipulated by probiotics, prebiotics, and symbiotics to promote successful cognitive aging. Registered under ClinicalTrials.gov Identifier no. NCT03080818.

Disinhibited Eating and Executive Functioning in Children and Adolescents: A Systematic Review and Meta-Analysis.

A growing body of research suggests disinhibited eating and weaker executive function (EF) are two risk factors for pediatric obesity. Emerging brain imaging and behavioral findings support the notion that EF skills impact eating regulation. However, a major gap in the current literature is a synthesis of the association between various EF skills and disinhibited eating patterns across child development. To address this gap, a systematic review and meta-analysis was conducted to examine the effect of EF skills on disinhibited eating behaviors among youth ages 3-18 years old. PubMed and PsychINFO databases were utilized and data from 15 studies with a total sample of 4909 youth were included. A random effects meta-analysis revealed a small negative effect of overall EF skills on disinhibited eating behavior, r = -0.14, p < 0.01. Analysis of individual EF skills found working memory had an overall medium negative effect on disinhibited eating behavior, r = -0.25, p < 0.05. Taken together, findings from this meta-analysis support an inverse relationship between EF abilities and disinhibited eating patterns in children and adolescents, such that poorer EF abilities are associated with higher levels of disinhibited eating. Given the effect on eating behavior, future research is needed to assess whether EF difficulties may be a barrier to effective weight management in youth. Specifically, research is needed to examine whether EF skills may be a key target to consider for effective obesity prevention and treatment in children and adolescents.

Specific agitation behaviours in dementia differentially contribute to aspects of caregiver burden.

BACKGROUND: Agitation is a common symptom in dementia and linked to caregiver burden, but both agitation and burden are multidimensional constructs. The current study sought to determine whether specific presentations of agitation differentially relate to aspects of caregiver burden. METHODS: Medical record data from an outpatient memory clinic were extracted for 609 persons with dementia, including caregiver-reported burden and care recipient agitation. RESULTS: Exploratory factor analysis yielded three domains of agitation on the Cohen Mansfield Agitation Inventory ('Physically Aggressive', 'Physically Non-Aggressive', 'Verbally Agitated') and four domains of burden on the Zarit Burden Interview ('Impact on Life', 'Guilt/Uncertainty', 'Embarrassment/Frustration', 'Overwhelm'). Regression analyses demonstrated all domains of agitation positively predicted overall burden. Regarding specific aspects of burden, Physically Aggressive behaviours predicted Embarrassment/Frustration. Physically Non-Aggressive behaviours predicted Impact on Life and Guilt/Uncertainty. Verbally Agitated behaviours predicted all burden dimensions. CONCLUSIONS: Results suggest specific aspects of agitation may differentially contribute to facets of caregiver burden.

Examining the cognitive benefits of probiotic supplementation in physically active older adults: A randomized clinical trial.

The prevalence of dementia is projected to increase with the growing older adult population and prevention strategies are urgently needed. Two promising interventions include physical activity (PA) and probiotic supplementation, with initial findings suggesting their combined use may confer greater cognitive benefits than either intervention alone. However, no study has yet examined the effects of probiotic supplementation on cognitive function in healthy, physically active older adults. The present study used archival data from a randomized clinical trial including 127 physically active, middle-aged to older adults (average age 64.3 years) with self-reported PA levels meeting or exceeding recommendations to investigate the effects of probiotic supplementation (Lactobacillus rhamnosus GG; L.GG) on cognitive outcomes. Repeated measures ANOVAs showed no significant changes in cognitive performance from baseline to follow up as an effect of L.GG consumption. These results suggest that probiotic supplementation may not improve cognitive function in persons already engaged in high levels of PA. Future research should include prospective studies to determine whether long-term use of probiotic supplementation may help prevent cognitive decline. Clinical trial registration: clinicaltrials.gov; study # NCT03080818. Novelty: Initial research shows promising cognitive benefits of combined PA and probiotics consumption. L.GG did not lead to acute cognitive improvements for older adults already meeting PA guidelines. Prospective studies examining prevention of cognitive decline with probiotics in healthy and clinical samples are much needed.

SCAT5 Sex Differences: Normative Data, Clinical Thresholds, and Relevance for Identification of Concussion.

OBJECTIVE: This study evaluated sex differences in performance on the Sport Concussion Assessment Tool-5 (SCAT5) Standardized Assessment of Concussion (SAC) and in baseline SCAT5 symptom reporting. It established clinically relevant cut points for low performance on the SAC based on both reliable chance indices (RCIs) and normative performance. This study also evaluated the diagnostic utility of the sex-adjusted SCAT5 SAC for identification of suspected concussion in collegiate athletes. METHOD: In total, 671 uninjured collegiate athletes were administered the SCAT5 and 264 of these athletes also completed SCAT5 testing ~1 year later. Fifty-four athletes were administered the SCAT5 after being removed from play due to suspected concussion. Sex differences in cognitive performance and symptom reporting at baseline were evaluated and sex-specific clinically relevant cut points were provided. Chi square and logistic regression models were used to evaluate if SAC performance was a significant predictor of concussion status. RESULTS: Female athletes outperformed male athletes on the SCAT 5 SAC and showed minimally higher symptom endorsement. Use of sex-corrected normative data improved performance of the SAC in identification of suspected concussion when a low score cut point was used. Logistic regression models showed that sex-corrected SAC change from baseline (RCI) improved the predictive value of the model after first accounting for other elements of the SCAT5. CONCLUSIONS: Present results support the use of sex-specific normative data for the SCAT5 SAC, particularly if using low performance without comparison to a baseline; however, reliable change from a pre-injury baseline may have somewhat higher diagnostic utility.