The Association of Neighborhood Socioeconomic Status with Executive Function and Processing Speed in Cognitively Normal Mexican American Elders from the Health and Aging Brains Study: Health Disparities Cohort.

INTRODUCTION: Neighborhood socioeconomic status (NSES) has been linked with overall health, and this study will evaluate whether NSES is cross-sectionally associated with cognition in non-Hispanic whites (NHWs) and Mexican Americans (MAs) from the Health and Aging Brain: Health Disparities Study (HABS-HD). METHODS: The HABS-HD is a longitudinal study conducted at the University of North Texas Health Science Center. The final sample analyzed (n = 1,312) were 50 years or older, with unimpaired cognition, and underwent an interview, neuropsychological examination, imaging, and blood draw. NSES was measured using the national area deprivation index (ADI) percentile ranking, which considered socioeconomic variables. Executive function and processing speed were assessed by the trail making tests (A and B) and the digit-symbol substitution test, respectively. Linear regression was used to assess the association of ADI and cognitive measures. RESULTS: MAs were younger, more likely to be female, less educated, had higher ADI scores, performed worse on trails B (all p < 0.05), and had lower prevalence of APOE4 + when compared to NHWs (p < 0.0001). A higher percentage of MAs lived in the most deprived neighborhoods than NHWs. For NHWs, ADI did not predict trails B or DSS scores, after adjusting for demographic variables and APOE4. For MAs, ADI predicted trails A, trails B, and DSS after adjusting for demographic covariates and APOE4 status. CONCLUSION: Our study revealed that living in an area of higher deprivation was associated with lower cognitive function in MAs but not in NHWs, which is important to consider in future interventions to slow cognitive decline.

The Link between APOE4 Presence and Neuropsychological Test Performance among Mexican Americans and Non-Hispanic Whites of the Multiethnic Health & Aging Brain Study - Health Disparities Cohort.

INTRODUCTION: The APOEε4 allele is the single strongest genetic risk for late-onset Alzheimer's disease (AD). Prior work demonstrates that not only the APOEε4 allele varies by race/ethnicity but also the risk for AD and cognitive impairment conveyed by the APOEε4 allele varies by the racial/ethnic group as well as genetic ancestry. Here, we sought to examine the link between the APOEε4 and neuropsychological functioning among Mexican Americans (MAs). METHODS: Data were examined from 1,633 (852 MAs and 781 non-Hispanic Whites [NHWs]) participants of the Health & Aging Brain Study - Health Disparities (HABS-HD) and were enrolled with all requisite data to be included into the current analyses. RESULTS: The frequency of both ε4 and ε2 alleles was significantly lower among MAs as compared to NHWs. Among MAs, APOEε4 allele presence was associated specifically with poorer immediate and delayed memory (Wechsler Memory Scale - Third Edition [WMS-III] Logical Memory and Spanish-English Verbal Learning Test [SEVLT]). Among NHWs, APOEε4 allele presence was associated with poorer immediate and delayed memory as well as worse executive functioning (Trials B) and verbal fluency (Animal naming). DISCUSSION/CONCLUSION: The APOEε4 allele was associated with poorer cognition across multiple domains among NHWs; however, allele presence was specifically associated with poorer memory performance among MAs. When combined with prior work, the current findings demonstrate that the risk factors associated with cognitive dysfunction differ among MAs as compared to NHWs and require additional investigation.

A blood screening tool for detecting mild cognitive impairment and Alzheimer's disease among community-dwelling Mexican Americans and non-Hispanic Whites: A method for increasing representation of diverse populations in clinical research.

INTRODUCTION: Representation of Mexican Americans in Alzheimer's disease (AD) clinical research has been extremely poor. METHODS: Data were examined from the ongoing community-based, multi-ethnic Health & Aging Brain among Latino Elders (HABLE) study. Participants underwent functional exams, clinical labs, neuropsychological testing, and 3T magnetic resonance imaging of the brain. Fasting proteomic markers were examined for predicting mild cognitive impairment (MCI) and AD using support vector machine models. RESULTS: Data were examined from n = 1649 participants (Mexican American n = 866; non-Hispanic White n = 783). Proteomic profiles were highly accurate in detecting MCI (area under the curve [AUC] = 0.91) and dementia (AUC = 0.95). The proteomic profiles varied significantly between ethnic groups and disease state. Negative predictive value was excellent for ruling out MCI and dementia across ethnic groups. DISCUSSION: A blood-based screening tool can serve as a method for increasing access to state-of-the-art AD clinical research by bridging between community-based and clinic-based settings.

Using Fractional Anisotropy Imaging to Detect Mild Cognitive Impairment and Alzheimer's Disease among Mexican Americans and Non-Hispanic Whites: A HABLE Study.

INTRODUCTION: Alzheimer's disease (AD) is the most frequently occurring neurodegenerative disease; however, little work has been conducted examining biomarkers of AD among Mexican Americans. Here, we examined diffusion tensor MRI marker profiles for detecting mild cognitive impairment (MCI) and dementia in a multi-ethnic cohort. METHODS: 3T MRI measures of fractional anisotropy (FA) were examined among 1,636 participants of the ongoing community-based Health & Aging Brain among Latino Elders (HABLE) community-based study (Mexican American n = 851; non-Hispanic white n = 785). RESULTS: The FA profile was highly accurate in detecting both MCI (area under the receiver operating characteristic curve [AUC] = 0.99) and dementia (AUC = 0.98). However, the FA profile varied significantly not only between diagnostic groups but also between Mexican Americans and non-Hispanic whites. CONCLUSION: Findings suggest that diffusion tensor imaging markers may have a role in the neurodiagnostic process for detecting MCI and dementia among diverse populations.

A depressive endophenotype of poorer cognition among cognitively healthy community-dwelling adults: results from the Western Australia memory study.

OBJECTIVE: The objective was to evaluate in a cognitively normal population the utility of an endophenotype of the depression-cognition link previously shown to be related to cognitive functioning in mild cognitive impairment and Alzheimer's disease. METHODS: The data of 460 cognitively normal adults aged 32-92 years (M = 63.5, standard deviation = 9.24) from the Western Australian Memory Study with the Cross-national comparisons of the Cambridge Cognitive Examination-revised (CAMCOG-R) scores and 30-item Geriatric Depression Scale (GDS) scores were analyzed to determine the relationship between the five-item depressive endophenotype (DepE) scale drawn from the GDS and level of performance on a measure of cognitive functioning. RESULTS: For the entire sample, there was a nonsignificant trend toward a negative relationship between DepE and CAMCOG-R scores. When analyzed for those 65 years and older, there was a significant negative relationship between the two measures (p = 0.001) with DepE scores significantly increasing the risk for performing more poorly on the CAMCOG-R (odds ratio = 1.53). Analysis of data for those 70 years and older showed that DepE was the only predictor significantly related to poorer CAMCOG-R performance (p = 0.001). For the 70 years and older group, DepE scores significantly increased the risk of poorer CAMCOG-R scores (odds ratio = 2.23). Analysis of the entire sample on the basis of ApoEε4 carrier status revealed that DepE scores were significantly negatively related only to ApoEε4 noncarrier regardless of age. CONCLUSIONS: Elevated DepE scores are associated with poor neuropsychological performance among cognitively normal older adults. Use of the DepE may allow for the identification of a subset of older adults where depression is a primary factor in cognitive decline and who may benefit from antidepressant therapies.

Total cholesterol and neuropsychiatric symptoms in Alzheimer's disease: the impact of total cholesterol level and gender.

BACKGROUND: Neuropsychiatric symptoms (NPS) in Alzheimer's disease (AD) are a major factor in nursing home placement and a primary cause of stress for caregivers. Elevated cholesterol has been linked to psychiatric disorders and has been shown to be a risk factor for AD and to impact disease progression. The present study investigated the relationship between cholesterol and NPS in AD. METHODS: Data on cholesterol and NPS from 220 individuals (144 females, 76 males) with mild-to-moderate AD from the Texas Alzheimer's Research and Care Consortium (TARCC) cohort were analyzed. The total number of NPS and symptoms of hyperactivity, psychosis, affect and apathy were evaluated. Groups based on total cholesterol (TC; ≥200 vs. <200 mg/dl) were compared with regard to NPS. The impact of gender was also assessed. RESULTS: Individuals with high TC had lower MMSE scores as well as significantly more NPS and more symptoms of psychosis. When stratified by gender, males with high TC had significantly more NPS than females with high TC or than males or females with low TC. CONCLUSION: The role of elevated cholesterol in the occurrence of NPS in AD appears to be gender and symptom specific. A cross-validation of these findings will have implications for possible treatment interventions, especially for males with high TC.

The Hachinski ischemic scale and cognition: the influence of ethnicity.

OBJECTIVE: cardiovascular burden is considered a risk factor for the development of cognitive dysfunction and dementia. While this link is well established in the literature, implementing this work in primary care settings remains a challenge. The goal of this study is to examine the utility of the Hachinski Ischemic Scale (HIS) in identifying cognitive dysfunction and diagnosis of mild cognitive impairment (MCI) in an ethnically diverse sample. METHODS: data were analysed on 517 participants (211 Mexican Americans and 306 non-Hispanic Whites) recruited from Project FRONTIER, a study of rural health. Neuropsychological measures were utilised to assess for cognitive functioning. RESULTS: among non-Hispanic Whites, HIS scores were significantly related to poorer performance on tasks of global cognition [B (SE) = -0.13 (0.06), P = 0.02], immediate memory [B (SE) = -0.85 (0.26), P < 0.001], attention [B (SE) = -1.6 (0.36), P < 0.001] and executive functioning [B (SE) = 0.46 (0.12), P < 0.001], and significantly predicted diagnosis of MCI [odds ratio (OR) = 1.4; 95% confidence interval (CI) = 1.2-1.6]. For Mexican Americans, HIS scores were significantly related to immediate memory [B (SE) = -0.78 (0.28), P = 0.01], attention [B (SE) = -0.74 (0.36), P = 0.04] and executive functioning [B (SE) = 0.37 (0.14), P = 0.01]; however, HIS scores were not significantly related to diagnosis of MCI in Mexican Americans (OR = 1.2, 95% CI = 0.96-1.4, P = 0.116). CONCLUSION: HIS scores were related to cognitive functioning; however, these results differed by ethnicity. It is possible that these findings indicate that vascular factors may increase risk for MCI among non-Hispanic Whites but not for Mexican Americans. These findings are consistent with past research that suggests risk factors for MCI may differ by ethnicity.

Basal Cell Carcinoma With Metastasis to the Thoracic Spine: An Uncommon Case Report and Review of the Literature.

Basal cell carcinoma is an exceedingly rare cause of spinal metastatic disease for which the treatment algorithm is poorly defined. We present a positive patient outcome after treatment of T8 metastatic basal with posterior decompression and fusion followed by later anterior reconstruction, in addition to targeted radiation therapy and pharmacologic therapy. In general, a personalized and comprehensive treatment approach should be used, incorporating surgical, oncologic, and pharmacologic methods as able. Moreover, primary preventive medical and mental health care can help prevent delayed presentation and increased access to timely care.

Characterization of Ptau181 Among a Diverse Community-Based Cohort: A HABS-HD Study.

Background: Examination of Alzheimer's disease (AD) related biomarkers among diverse communities has remained limited. Objective: The aim of this study was to expand on prior work to provide a characterization of ptau181 among a diverse community sample. Consideration was taken regarding the impact of comorbidities on ptau181 levels including medical. Methods: 3,228 (n = 770 African American [AA], n = 1,231 Hispanic, and n = 1,227 non-Hispanic white [NHW]) Health and Aging Brain Study- Health Disparities (HABS-HD) participants were included in this study. ANCOVAs were conducted to examine differences in ptau181 levels across race and ethnic groups. Violin plots were also generated stratified by APOEɛ4 carrier status, Amyloid PET positivity status, medical comorbidity (hypertension, dyslipidemia, chronic kidney disease [CKD], and diabetes) and by cognitive diagnosis. Results: Ptau181 levels were found to differ between Hispanics and NHW after covarying for age, sex, and APOEɛ4 status. Amyloid PET positivity was associated with higher ptau181 levels across all groups. APOEɛ4 positivity status was only significantly associated with ptau181 levels among AAs. Across all race and ethnic groups, those with a diagnosis of CKD had higher levels of ptau181. When stratified by cognitive diagnosis, cognitively unimpaired Hispanics had higher ptau181 if they also had a diagnosis of CKD or diabetes. p-values ≤0.01. Conclusions: Differences in ptau181 levels were shown in a diverse community sample. Medical comorbidities had a differing effect on ptau181 levels particularly among Hispanics even without cognitive impairment. Findings support the need for future work to consider comorbid conditions when examining the utility of ptau181.

Cognitive differences among depressed and non-depressed MCI participants: a project FRONTIER study.

OBJECTIVE: Depression is the most commonly reported psychiatric symptom in patients with mild cognitive impairment (MCI). However, more research is needed examining the impact of depression on cognitive functioning in MCI patients. The purpose of this study was to examine differences in cognitive functioning in a sample of community- based, depressed, and non-depressed MCI patients. METHODS: One hundred and five participants with MCI were included in this study. Participants were recruited from Project FRONTIER, a study of rural health. Depression was assessed via the Geriatric Depression Scale (GDS-30), and cognition was measured using the Repeatable Battery for the Assessment of Neuropsychological Status. RESULTS: The results indicated that depressed MCI participants performed significantly worse than their non-depressed counterparts on several cognitive measures. MCI participants with depression scored significantly lower on immediate memory (t = 3.4, p < 0.01) and delayed memory (t = 2.8, p < 0.01) indices than their non-depressed counterparts. CONCLUSIONS: The results of this study indicated that MCI participants with depression experienced greater deficits in cognitive functioning than their non-depressed counterparts. Depressed MCI participants exhibited greater deficits in both immediate and delayed memory. Thus, identifying and treating depression in individuals with MCI may improve memory and cognitive functioning.

The impact of GPX1 on the association of groundwater selenium and depression: a Project FRONTIER study.

BACKGROUND: Prior animal model and human-based studies have linked selenium concentrations to decreased risk for depression; however, this work has not focused on household groundwater levels or specific depressive symptoms. The current study evaluated the link between groundwater selenium levels and depression. We also sought to determine if a functional polymorphism in the glutathione peroxidase 1 (GPX1) gene impacted this link. METHODS: We used a cross-sectional design to analyze data from 585 participants (183 men and 402 women) from Project FRONTIER, a study of rural health in West Texas. Residential selenium concentrations were estimated using Geospatial Information System (GIS) analyses. Linear regression models were created using Geriatric Depression Scale (GDS-30) total and subfactor scores as outcome variables and selenium concentrations as predictor variables. Analyses were re-run after stratification of the sample on GPX1 Pro198Leu genotype (rs1050454). RESULTS: Selenium levels were significantly and negatively related to all GDS and subfactor scores accounting for up to 17% of the variance beyond covariates. Selenium was most strongly protective against depression among homozygous carriers of the C allele at the Pro198Leu polymorphism of the GPX1 gene. Analyses also point towards a gene-environmental interaction between selenium exposure and GPX1 polymorphism. CONCLUSION: Our results support the link between groundwater selenium levels and decreased depression symptoms. These findings also highlight the need to consider the genetics of the glutathione peroxidase system when examining this relationship, as variation in the GPX1 gene is related to depression risk and significantly influences the protective impact of selenium, which is indicative of a gene-environment interaction.

Plasma Biomarkers of Alzheimer's Disease Are Associated with Physical Functioning Outcomes Among Cognitively Normal Adults in the Multiethnic HABS-HD Cohort.

In this study, we examined the link between plasma Alzheimer's disease (AD) biomarkers and physical functioning outcomes within a community-dwelling, multiethnic cohort. Data from 1 328 cognitively unimpaired participants (n = 659 Mexican American and n = 669 non-Hispanic White) from the ongoing Health & Aging Brain Study-Health Disparities (HABS-HD) cohort were examined. Plasma AD biomarkers (amyloid beta [Aß]40, Aß42, total tau [t-tau], and neurofilament light chain [NfL]) were assayed using the ultra-sensitive Simoa platform. Physical functioning measures were the Timed Up and Go (TUG) and the Short Physical Performance Battery (SPPB). Cross-sectional linear regression analyses revealed that plasma Aß 40 (p < .001), Aß 42 (p = .003), and NfL (p < .001) were each significantly associated with TUG time in seconds. Plasma Aß 40 (p < .001), Aß 42 (p < .001), t-tau (p = .002), and NfL (p < .001) were each significantly associated with SPPB Total Score. Additional analyses demonstrate that the link between plasma AD biomarkers and physical functioning outcomes were strongest among Mexican Americans. Plasma AD biomarkers are receiving a great deal of attention in the literature and are now available clinically including use in clinical trials. The examination of AD biomarkers and physical functioning may allow for the development of risk profiles, which could stratify a person's risk for neurodegenerative diseases, such as AD, based on plasma AD biomarkers, physical functioning, ethnicity, or a combination of these measures prior to the onset of cognitive impairment.

Evaluation of Neighborhood-Level Disadvantage and Cognition in Mexican American and Non-Hispanic White Adults 50 Years and Older in the US.

Importance: Understanding how socioeconomic factors are associated with cognitive aging is important for addressing health disparities in Alzheimer disease. Objective: To examine the association of neighborhood disadvantage with cognition among a multiethnic cohort of older adults. Design, Setting, and Participants: In this cross-sectional study, data were collected between September 1, 2017, and May 31, 2022. Participants were from the Health and Aging Brain Study-Health Disparities, which is a community-based single-center study in the Dallas/Fort Worth area of Texas. A total of 1614 Mexican American and non-Hispanic White adults 50 years and older were included. Exposure: Neighborhood disadvantage for participants' current residence was measured by the validated Area Deprivation Index (ADI); ADI Texas state deciles were converted to quintiles, with quintile 1 representing the least disadvantaged area and quintile 5 the most disadvantaged area. Covariates included age, sex, and educational level. Main Outcomes and Measures: Performance on cognitive tests assessing memory, language, attention, processing speed, and executive functioning; measures included the Spanish-English Verbal Learning Test (SEVLT) Learning and Delayed Recall subscales; Wechsler Memory Scale, third edition (WMS-III) Digit Span Forward, Digit Span Backward, and Logical Memory 1 and 2 subscales; Trail Making Test (TMT) parts A and B; Digit Symbol Substitution Test (DSST); Letter Fluency; and Animal Naming. Raw scores were used for analyses. Associations between neighborhood disadvantage and neuropsychological performance were examined via demographically adjusted linear regression models stratified by ethnic group. Results: Among 1614 older adults (mean [SD] age, 66.3 [8.7] years; 980 women [60.7%]), 853 were Mexican American (mean [SD] age, 63.9 [7.9] years; 566 women [66.4%]), and 761 were non-Hispanic White (mean [SD] age, 69.1 [8.7] years; 414 women [54.4%]). Older Mexican American adults were more likely to reside in the most disadvantaged areas (ADI quintiles 3-5), with 280 individuals (32.8%) living in ADI quintile 5, whereas a large proportion of older non-Hispanic White adults resided in ADI quintile 1 (296 individuals [38.9%]). Mexican American individuals living in more disadvantaged areas had worse performance than those living in ADI quintile 1 on 7 of 11 cognitive tests, including SEVLT Learning (ADI quintile 5: ß = -2.50; 95% CI, -4.46 to -0.54), SEVLT Delayed Recall (eg, ADI quintile 3: ß = -1.11; 95% CI, -1.97 to -0.24), WMS-III Digit Span Forward (eg, ADI quintile 4: ß = -1.14; 95% CI, -1.60 to -0.67), TMT part A (ADI quintile 5: ß = 7.85; 95% CI, 1.28-14.42), TMT part B (eg, ADI quintile 5: ß = 31.5; 95% CI, 12.16-51.35), Letter Fluency (ADI quintile 4: ß = -2.91; 95% CI, -5.39 to -0.43), and DSST (eg, ADI quintile 5: ß = -4.45; 95% CI, -6.77 to -2.14). In contrast, only non-Hispanic White individuals living in ADI quintile 4 had worse performance than those living in ADI quintile 1 on 4 of 11 cognitive tests, including SEVLT Learning (ß = -2.35; 95% CI, -4.40 to -0.30), SEVLT Delayed Recall (ß = -0.95; 95% CI, -1.73 to -0.17), TMT part B (ß = 15.95; 95% CI, 2.47-29.44), and DSST (ß = -3.96; 95% CI, -6.49 to -1.43). Conclusions and Relevance: In this cross-sectional study, aging in a disadvantaged area was associated with worse cognitive functioning, particularly for older Mexican American adults. Future studies examining the implications of exposure to neighborhood disadvantage across the life span will be important for improving cognitive outcomes in diverse populations.

Characterizing Plasma Biomarkers of Alzheimer's in a Diverse Community-Based Cohort: A Cross-Sectional Study of the HAB-HD Cohort.

Background: Due to their low cost, less invasive nature, and ready availability, plasma biomarkers of Alzheimer's disease have been proposed as one-time screening tools for clinical trials and research. The impact of ethnoracial factors on these biomarkers has received little attention. The current cross-sectional study investigated the levels of Aß40, Aß42, total tau (t tau), and neurofilament light (NfL) across diagnoses for each of the three major ethnoracial groups in the United States in a community-based cohort of older adults. Methods: A total of 1,862 participants (852 Mexican Americans (MAs); 775 non-Hispanic Whites (NHWs), and 235 African Americans (AAs)) drawn from The Health & Aging Brain Study-Health Disparities (HABS-HD) study were included. Diagnoses were assigned using an algorithm (decision tree) verified by consensus review. Plasma samples were assayed using Simoa technology. Levels of each biomarker were compared for the three ethnoracial groups across cognitive diagnoses using ANOVA covarying sex and age. Results: Significant differences were found across the groups at each level of cognitive impairment. Cognitively unimpaired (CU) AA had significantly lower levels of each of the biomarkers than cognitively unimpaired MA or NHW and NHW had higher levels of Aß40, and NfL than the other two groups. MA had higher t tau than AA or NHW. Mild cognitive impairment (MCI) group NHW had the highest levels on all the biomarkers and AA had the lowest. NHW and MA have higher levels of Aß40, Aß42, and t tau there was no difference between the groups for Aß42. NHW had significantly higher levels of Aß40, t tau, and NfL than AA. AA had a higher Aß42/Aß40 ratio than either NHW or MA for CU MCI. Conclusions: The use of plasma biomarkers of cognitive decline is promising given their advantages over other biomarkers such as CSF and imaging but as the current research shows, ethnoracial differences must be considered to enhance accuracy and utility. Developing ethnoracial-specific cut points and establishing normative ranges by assay platform for each of the biomarkers are needed. Longitudinal research to assess changes in biomarkers during a cognitive decline is ongoing.

Cartilage and Meniscus Injuries Are More Common in Patients Undergoing Delayed Multiligament Reconstruction.

The purpose of this study was to describe the pattern of meniscus and cartilage pathology in multiligament knee injuries (MLKIs) and determine the relationship between surgical timing and injury mechanism with degree of intra-articular injury. Patients with surgically treated MLKIs over a 15-year period were retrospectively reviewed and grouped based on surgical intervention, time to intervention, and injury mechanism. The presence or absence of meniscus and chondral injury were recorded at the time of surgery. Surgical intervention within 6 weeks of injury was deemed acute, while surgery occurring more than 6 weeks from injury was classified as delayed. Over the 15-year study period, 207 patients with MLKIs were identified. Compared with acutely managed patients, the delayed intervention group had significantly more meniscus (p = 0.03) and cartilage (p < 0.01) pathology. Meniscus injury rates in MLKIs sustained during sporting activity did not differ from nonsporting injuries (p = 0.63). However, the nonsporting group had significantly more chondral injuries (p < 0.01). High-energy injury mechanism was associated with increased cartilage (p = 0.02), but not meniscus (p = 0.61) injury rates. In conclusion, surgical reconstruction of MLKIs delayed for more than 6 weeks was associated with increased meniscus and cartilage pathology.

Return of Scapulohumeral Rhythm in Patients After Reverse Shoulder Arthroplasty: A Midterm Stereoradiographic Imaging Analysis.

Background: Reverse shoulder arthroplasty (RSA) is associated with high rates of midterm complications including scapular notching, implant wear, and mechanical impingement. Scapulo-humeral rhythm (SHR), described by Codman in the 1920's, is defined as the ratio of glenohumeral motion to scapulothoracic motion. SHR is used as an indicator of shoulder dysfunction, as alterations in SHR can have profound implications on shoulder biomechanics. The determination of SHR can be hindered by soft-tissue motion artifacts and high radiation burdens associated with traditional surface marker or fluoroscopic analysis. EOS low dose stereoradiographic imaging analysis utilizing 3D model construction from a 2D X-ray series may offer an alternative modality for characterizing SHR following RSA. Methods: Patients (n=10) underwent an EOS imaging analysis to determine SHR at six and twelve months post-RSA. Leveraging 3D models of the implants, 2D/3D image registration methods were used to calculate relative glenohumeral and scapulothoracic positioning at 60, 90 and 120° of shoulder elevation. Subject-specific SHR curves were assessed and midterm changes in post-RSA SHR associated with follow-up time and motion phase were evaluated. Pearson correlations assessed associations between patient-specific factors and post-RSA SHR. Results: Mean post-RSA SHR was 0.81:1 across subjects during the entire midterm postoperative period. As a cohort, post-RSA SHR was more variable for 60-90° of shoulder motion. SHR for 90-120° of motion decreased (0.43:1) at twelve months post-RSA. Post-RSA SHR could be categorized using three relative motion curve patterns, and was not strongly associated with demographic factors such as BMI. 50% of subjects demonstrated a different SHR relative motion curve shape at twelve months post-RSA, and SHR during the 90120° of motion was found to generally decrease at twelve months. Conclusion: Midterm post-RSA SHR was successfully evaluated using EOS technology, revealing lower SHR values (i.e., greater scapulothoracic motion) compared to normal values reported in the literature. SHR continued to change for some subjects during the midterm post-RSA period, with the greatest change during 90-120° of shoulder motion. Study findings suggest that future post RSA rehabilitation efforts to address elevated scapulothoracic motion may benefit from being patient-specific in nature and targeting scapular stabilization during 90-120° of shoulder motion. Level of Evidence: IV.

Proteomic Profiles of Neurodegeneration Among Mexican Americans and Non-Hispanic Whites in the HABS-HD Study.

BACKGROUND: Hispanics are expected to experience the largest increase in Alzheimer's disease (AD) and AD related dementias over the next several decades. However, few studies have examined biomarkers of AD among Mexican Americans, the largest segment of the U.S. Hispanic population. OBJECTIVE: We sought to examine proteomic profiles of an MRI-based marker of neurodegeneration from the AT(N) framework among a multi-ethnic, community-dwelling cohort. METHODS: Community-dwelling Mexican Americans and non-Hispanic white adults and elders were recruited. All participants underwent comprehensive assessments including an interview, functional exam, clinical labs, informant interview, neuropsychological testing, and 3T MRI of the brain. A neurodegeneration MRI meta-ROI biomarker for the AT(N) framework was calculated. RESULTS: Data was examined from n = 1,291 participants. Proteomic profiles were highly accurate for detecting neurodegeneration (i.e., N+) among both Mexican Americans (AUC = 1.0) and non-Hispanic whites (AUC = 0.98). The proteomic profile of N + was different between ethnic groups. Further analyses revealed that the proteomic profiles of N + varied by diagnostic status (control, MCI, dementia) and ethnicity (Mexican American versus non-Hispanic whites) though diagnostic accuracy was high for all classifications. CONCLUSION: A proteomic profile of neurodegeneration has tremendous value and point towards novel diagnostic and intervention opportunities. The current findings demonstrate that the underlying biological factors associated with neurodegeneration are different between Mexican Americans versus non-Hispanic whites as well as at different levels of disease progression.

Vascular risk profile and white matter hyperintensity volume among Mexican Americans and non-Hispanic Whites: The HABLE study.

INTRODUCTION: Among vascular risk factors we hypothesized that an increased prevalence of diabetes in Hispanics would be associated with greater white matter hyperintensity (WMH) volume, which may contribute to cognitive decline. METHODS: A total of 1318 participants (60% female; 49% Hispanic, 51% non-Hispanic White; age 66.2 ± 8.9 years) underwent clinical evaluation and brain magnetic resonance imaging (MRI). WMH volume associations were assessed with age, sex, and ethnicity and then with vascular risk factors in a selective regression model. RESULTS: WMH volume was greater with older age (P < .0001), Hispanic ethnicity (P = .02), and female sex (P = .049). WMH volume was best predicted by age, diastolic blood pressure, hypertension history, hemoglobin A1c (HbA1c), white blood cell count, and hematocrit (P < .01 for all). Elevated HbA1c was associated with greater WMH volume among Hispanics (parameter estimate 0.08 ± 0.02, P < .0001) but not non-Hispanic Whites (parameter estimate 0.02 ± 0.04, P = .5). DISCUSSION: WMH volume was greater in Hispanics, which may be partly explained by increased WMH volume related to elevated HbA1c among Hispanics but not non-Hispanic Whites.

Serum brain-derived neurotrophic factor levels are specifically associated with memory performance among Alzheimer's disease cases.

AIMS: Our purpose was to study the link between serum brain-derived neurotrophic factor (BDNF) levels and neuropsychological functioning through the Texas Alzheimer's Research Consortium cohort. METHODS: A total of 399 participants [probable Alzheimer's disease (AD) n = 198, controls n = 201] were available for analysis. The BDNF levels were assayed via multiplex immunoassay. Regression analyses were utilized to examine the relation between BDNF levels and neuropsychological functioning. RESULTS: There were no significant mean differences in BDNF levels between cases and controls. In the AD group, the BDNF levels were significantly negatively associated with the scores on immediate [B = -0.07 (0.02), t = -3.55, p = 0.001] and delayed [B = -0.05 (0.02), t = -2.79, p = 0.01] verbal memory and immediate [B = -0.12 (0.05), t = -2.70, p = 0.01] visual memory. No other neuropsychological variables were significantly related to the BDNF levels. The BDNF levels were not significantly related to the neuropsychological test scores in the control group. CONCLUSIONS: Increased serum BDNF levels were associated with poorer visual and verbal memory, but only among AD cases. The current findings point toward an upregulation of serum BDNF as one possible mechanism linked to memory disturbances in AD though it does not appear to be linked to disease severity.

The differential impact of depressive symptom clusters on cognition in a rural multi-ethnic cohort: a Project FRONTIER study.

OBJECTIVE: To examine the differential impact of depressive symptom clusters on neuropsychological functioning in a rural-dwelling, multi-ethnic cohort. METHODS: Data were analyzed for 184 participants (70% female, 46% Hispanic) who are part of an ongoing rural healthcare study, Project FRONTIER. Previously published factor scores of dysphoria, meaninglessness, apathy, and cognitive impairment from the GDS-30 were entered as predictor variables in linear regression models with RBANS Index raw scores as outcome variables. RESULTS: In the total sample, Dysphoria, Meaninglessness, and Cognitive Impairment were significantly associated with Immediate Memory, Language, Attention and Delayed Memory; Dysphoria was also significantly related to Visuospatial skills. When examined by gender and ethnicity, however, the findings varied with dysphoria being most related to cognitive status among men and dysphoria, meaninglessness, and cognitive impairment being most significantly related to cognitive status among women. When examined by ethnicity, dysphoria, meaninglessness, and cognitive impairment were most strongly associated with immediate and delayed memory in Hispanics. CONCLUSIONS: In this study of rural-dwelling adults and elders, depressive symptom clusters were differentially associated with poorer cognition with the most consistent findings being between depressive symptoms of dysphoria and meaninglessness and the cognitive domains of immediate and delayed memory.