The Role of Transportation in the Enrollment of Elderly African Americans into Exercise and Memory Study: GEMS Study.

BACKGROUND: Understanding the factors driving recruitment and enrollment of African Americans (AA)s in clinical translational research will assure that underrepresented populations benefit from scientific progress and new developments in the diagnosis and treatment of Alzheimer's disease and related disorders. While transportation is pivotal to volunteers' ability to participate in research, its contribution to enrollment in exercise studies on AD is yet to be elucidated. Thus, this research focuses on identifying factors that influence the recruitment and enrollment of African Americans in biomedical studies and determining whether the availability of transportation motivates participation in time-demanding exercise studies on AD. METHODS: We analyzed recruitment data collected from 567 volunteers ages 55 and older screened through various recruitment sources and considered for enrollment in our exercise and memory study. To determine whether transportation influenced the enrollment of African Americans (AA)s in biomedical studies, multiple logistic regression analysis was performed to identify significant factors that drive enrollment. Furthermore, the association of race and demographic factors on the availability of transportation was assessed. RESULTS: Demographic factors, age at screening, education, gender, and cognitive scores were not significantly different among those enrolled compared to control (not-enrolled). In the relationship of enrollment to transportation, enrolled participants were more likely to have access to transportation (79.12%) than not-enrolled participants who had less access to transportation (71.6%); however, the association was not statistically significant. However, race differentially influenced the likelihood of enrollment, with elderly AAs being significantly less likely to have transportation (p = 0.020) than the Whites but more likely than "others" to have transportation. CONCLUSION: Our findings suggest that access to transportation may be a key factor motivating enrollment in an exercise and memory study in a predominantly AA sample. Notably, AAs in our sample were less likely to have transportation than Whites. Other demographic factors and cognitive scores did not significantly influence enrollment in our sample. A larger sample and more detailed assessment of transportation are needed to further discern the role of transportation in clinical trials.

Use of a community advisory board to build equitable algorithms for participation in clinical trials: a protocol paper for HoPeNET.

INTRODUCTION: Participation from racial and ethnic minorities in clinical trials has been burdened by issues surrounding mistrust and access to healthcare. There is emerging use of machine learning (ML) in clinical trial recruitment and evaluation. However, for individuals from groups who are recipients of societal biases, utilisation of ML can lead to the creation and use of biased algorithms. To minimise bias, the design of equitable ML tools that advance health equity could be guided by community engagement processes. The Howard University Partnership with the National Institutes of Health for Equitable Clinical Trial Participation for Racial/Ethnic Communities Underrepresented in Research (HoPeNET) seeks to create an ML-based infrastructure from community advisory board (CAB) experiences to enhance participation of African-Americans/Blacks in clinical trials. METHODS AND ANALYSIS: This triphased cross-sectional study (24 months, n=56) will create a CAB of community members and research investigators. The three phases of the study include: (1) identification of perceived barriers/facilitators to clinical trial engagement through qualitative/quantitative methods and systems-based model building participation; (2) operation of CAB meetings and (3) development of a predictive ML tool and outcome evaluation. Identified predictors from the participant-derived systems-based map will be used for the ML tool development. ETHICS AND DISSEMINATION: We anticipate minimum risk for participants. Institutional review board approval and informed consent has been obtained and patient confidentiality ensured.

Digital Food Records in Community-Based Interventions: Mixed-Methods Pilot Study.

BACKGROUND: A pressing need exists to understand and optimize the use of dietary assessment tools that can be used in community-based participatory research (CBPR) interventions. A digital food record, which uses a mobile device to capture the dietary intake through text and photography inputs, is a particularly promising mobile assessment method. However, little is understood about the acceptability and feasibility of digital food records in CBPR and how to best tailor dietary assessment tools to the needs of a community. OBJECTIVE: The objective of our study was to evaluate the acceptability and feasibility of digital food records among church-based populations in resource-limited wards of Washington, DC, USA, using a mixed-methods approach. METHODS: This community-based pilot study was conducted as part of the Washington, DC Cardiovascular Health and Needs Assessment. Participants (n=17) received a mobile device (iPod Touch) to photodocument their dietary intake for a 3-day digital food record using a mobile app, FitNinja (Vibrent Health). The acceptability of the digital food record was explored through the thematic analysis of verbatim transcripts from a moderated focus group (n=8). In addition, the feasibility was evaluated by the percentage of participants complying with instructions (ie, capturing both before and after meal photos for at least 2 meals/day for 3 days). RESULTS: Qualitative themes identified were related to (1) the feasibility and acceptability of the mobile device and app, including issues in recording the dietary information and difficulty with photodocumentation; (2) suggestions for additional support and training experiences; and (3) comparisons with other mobile apps. Overall, the participants accepted the digital food record by demonstrating satisfaction with the tool and intent to continue the use (eg, participants recorded an average of 5.2, SD 7, consecutive days). Furthermore, of the 17 participants, 15 photodocumented at least 1 meal during the study period and 3 fully complied with the digital food record instructions. CONCLUSIONS: This study demonstrated digital food records as an acceptable tool in CBPR and identified contributors and barriers to the feasibility of digital food records for future research. Engaging community members in the implementation of novel assessment methods allows for the tailoring of technology to the needs of the community and optimizing community-based interventions. TRIAL REGISTRATION: ClinicalTrials.gov NCT01927783; https://www.clinicaltrials.gov/ct2/show/NCT01927783 (Archived by WebCite at http://www.webcitation.org/70WzaFWb6).

Associations of Pulse and Blood Pressure with Hippocampal Volume by APOE and Cognitive Phenotype: The Alzheimer's Disease Neuroimaging Initiative (ADNI).

BACKGROUND: It is increasingly evident that high blood pressure can promote reduction in global and regional brain volumes. While these effects may preferentially affect the hippocampus, reports are inconsistent. METHODS: Using data from the Alzheimer's Disease Neuroimaging Initiative (ADNI), we examined the relationships of hippocampal volume to pulse pressure (PPR) and systolic (SBP) and diastolic (DBP) blood pressure according to apolipoprotein (APOE) ɛ4 positivity and cognitive status. The ADNI data included 1,308 participants: Alzheimer disease (AD = 237), late mild cognitive impairment (LMCI = 454), early mild cognitive impairment (EMCI = 254), and cognitively normal (CN = 365), with up to 24 months of follow-up. RESULTS: Higher quartiles of PPR were significantly associated with lower hippocampal volumes (Q1 vs. Q4, p = 0.034) in the CN and AD groups, but with increasing hippocampal volume (Q1, p = 0.008; Q2, p = 0.020; Q3, p = 0.017; Q4 = reference) in the MCI groups. In adjusted stratified analyses among non-APOE ɛ4 carriers, the effects in the CN (Q1 vs. Q4, p = 0.006) and EMCI groups (Q1, p = 0.002; Q2, p = 0.013; Q3, p = 0.002; Q4 = reference) remained statistically significant. Also, higher DBP was significantly associated with higher hippocampal volume (p = 0.002) while higher SBP was significantly associated with decreasing hippocampal volume in the EMCI group (p = 0.015). CONCLUSION: Changes in PPR, SBP, and DBP differentially influenced hippocampal volumes depending on the cognitive and APOE genotypic categories.

Best strategies to recruit and enroll elderly Blacks into clinical and biomedical research.

BACKGROUND: Historically, Blacks have been disproportionately underrepresented in clinical trials. Outcomes associated with low Blacks' participation in research include poor understanding of the predictors and treatment of the disease, increasing health disparities, poor health equity, and suboptimal wellness of the nation as a whole. To address this gap in research participation, we analyzed our recruitment data to identify the most effective strategies for enrolling older Blacks in clinical trials. METHODS: Data used in these analyses were obtained from 3,266 potential volunteers, ages 50 or older, who completed a Mini-Mental State Exam as part of recruitment and screening for various clinical studies on Alzheimer's disease. In order to determine the most effective strategies for engaging Blacks in clinical research, we used tests of proportion to assess significant differences in recruitment sources, counts, and percentages for optimal recruitment strategies by gender. Finally, we employed regression analyses to confirm our findings. RESULTS: Of the total 3,266 screened, 2,830 Black volunteers were identified for further analysis. Overall, more women than men (73.8% vs 26.2%) participated in our recruitment activities. However, a significantly higher proportion of men than women were engaged through family (3.86% vs 1.30%, p=0.0004) and referral sources (5.89% vs 2.59%, p=0.0005). Compared to other sources for recruitment, we encountered a higher proportion of volunteers at health fairs (42.95%), and through advertisements (14.97%). In our sample, years of education and age did not appear to influence the likelihood of an encounter, screening, and potential participation. CONCLUSION: Our findings indicate Black men and women in our sample were predominantly recruited from health fairs and through advertisements tailored to their health needs and interests. Conversely, we mostly engaged Black men through family referrals and persons known to them, indicating a need for trust in their decision to engage study personnel and/or participate in clinical trials.

Examining relationships between perceptions and objective assessments of neighborhood environment and sedentary time: Data from the Washington, D.C. Cardiovascular Health and Needs Assessment.

Sedentary time (ST) and neighborhood environment (NE) are predictors of cardiovascular (CV) health. However, little is known about ST's relationship with NE. We examined associations of perceived and objective NE with ST in the predominantly African American faith-based population of the Washington, D.C. CV Health and Needs Assessment. After using community-based research principles, participants reported NE perceptions, including sidewalks, recreational areas, and crime presence. Factor analysis was conducted to explore pertinent constructs; factor sums were created and combined as Total Perception Score (TPS) (higher score = more favorable perception). Objective NE was assessed using Google Maps and the Active Neighborhood Checklist (ANC). ST was self-reported. Linear regression determined relationships between TPS and ST, and ANC scores and ST, for 1) overall population, 2) lower median-income D.C. areas, and 3) higher median-income DC and Maryland areas. For the sample (N = 98.9% African-American, 78% female), lower median-income areas had significantly lower mean TPS and ANC scores than higher median-income areas (p < 0.001). Three factors (neighborhood violence, physical/social environment, and social cohesion) were associated with overall NE perception. Among those in lower median-income areas, there was a negative association between TPS and ST that remained after covariate adjustment; this was not observed in higher median-income areas. There was no association between ANC scores and ST. Poorer NE perception is associated with greater ST for those in lower income areas, while objective environment is not related to ST. Multi-level interventions are needed to improve NE perceptions in lower-median income areas, reduce ST, and improve CV health.

Adherence with physical activity monitoring wearable devices in a community-based population: observations from the Washington, D.C., Cardiovascular Health and Needs Assessment.

Wearable mobile health (mHealth) technologies offer approaches for targeting physical activity (PA) in resource-limited, community-based interventions. We sought to explore user characteristics of PA tracking, wearable technology among a community-based population within a health and needs assessment. In 2014-2015, we conducted the Washington, D.C., Cardiovascular Health and Needs Assessment in predominantly African-American churches among communities with higher obesity rates and lower household incomes. Participants received a mHealth PA monitor and wirelessly uploaded PA data weekly to church data collection hubs. Participants (n = 99) were 59 ± 12 years, 79% female, and 99% African-American, with a mean body mass index of 33 ± 7 kg/m2. Eighty-one percent of participants uploaded PA data to the hub and were termed "PA device users." Though PA device users were more likely to report lower household incomes, no differences existed between device users and non-users for device ownership or technology fluency. Findings suggest that mHealth systems with a wearable device and data collection hub may feasibly target PA in resource-limited communities.

Community Engagement to Optimize the Use of Web-Based and Wearable Technology in a Cardiovascular Health and Needs Assessment Study: A Mixed Methods Approach.

BACKGROUND: Resource-limited communities in Washington, D.C. have high rates of obesity-related cardiovascular disease in addition to inadequate physical activity (PA) facilities and limited Internet access. Engaging community members in the design and implementation of studies to address these health disparities is essential to the success of community-based PA interventions. OBJECTIVE: The objective of the study was to use qualitative and quantitative methods to evaluate the feasibility and acceptability of PA-monitoring wristbands and Web-based technology by predominantly African American, church-based populations in resource-limited Washington, D.C. neighborhoods. METHODS: To address cardiovascular health in at-risk populations in Washington, D.C., we joined community leaders to establish a community advisory board, the D.C. Cardiovascular Health and Obesity Collaborative (D.C. CHOC). As their first initiative, the Washington, D.C. Cardiovascular Health and Needs Assessment intends to evaluate cardiovascular health, social determinants of health, and PA-monitoring technologies. At the recommendation of D.C. CHOC members, we conducted a focus group and piloted the proposed PA-monitoring system with community members representing churches that would be targeted by the Cardiovascular Health and Needs Assessment. Participants (n=8) agreed to wear a PA-monitoring wristband for two weeks and to log cardiovascular health factors on a secure Internet account. Wristbands collected accelerometer-based data that participants uploaded to a wireless hub at their church. Participants agreed to return after two weeks to participate in a moderated focus group to share experiences using this technology. Feasibility was measured by Internet account usage, wristband utilization, and objective PA data. Acceptability was evaluated through thematic analysis of verbatim focus group transcripts. RESULTS: Study participants (5 males, 3 females) were African American and age 28-70 years. Participant wristbands recorded data on 10.1±1.6 days. Two participants logged cardiovascular health factors on the website. Focus group transcripts revealed that participants felt positively about incorporating the device into their church-based populations, given improvements were made to device training, hub accessibility, and device feedback. CONCLUSIONS: PA-monitoring wristbands for objectively measuring PA appear to be a feasible and acceptable technology in Washington, D.C., resource-limited communities. User preferences include immediate device feedback, hands-on device training, explicit instructions, improved central hub accessibility, and designation of a church member as a trained point-of-contact. When implementing technology-based interventions in resource-limited communities, engaging the targeted community may aid in early identification of issues, suggestions, and preferences. TRIAL REGISTRATION: ClinicalTrials.gov NCT01927783; https://clinicaltrials.gov/ct2/show/NCT01927783 (Archived by WebCite at http://www.webcitation.org/6f8wL117u).

Mutant Strain of Bradyrhizobium japonicum with Increased Symbiotic N(2) Fixation Rates and Altered Mo Metabolism Properties.

Mutant strains of Bradyrhizobium japonicum that required higher levels of molybdate than the wild-type strain for growth on NO(3)-containing medium were obtained after transposon Tn5 mutagenesis of the wild-type strain. The mutant strains expressed more than fivefold-greater nitrate reductase activities in the range of 0.1 to 1.0 mM added molybdate compared with activities expressed upon incubation in non-Mo-supplemented medium, whereas the nitrate reductase activity of the wild-type strain (JH) was not markedly influenced by Mo supplementation. In free-living culture, mutant strains JH310 and JH359 expressed substantial nitrogenase activity, even in medium treated to remove molybdate, and nitrogenase activity was influenced little by Mo supplementation, whereas the wild-type strain required 100 nM added Mo for highest nitrogenase activity. Double-reciprocal plots of Mo uptake rates versus Mo concentration showed that both bacteroids and free-living cells of mutant strain JH359 had about the same affinity for Mo as did the parent strain. Bacteroids of both the mutants and the wild type also exhibited similar Mo accumulation rates over a 9-min period under very-low-Mo (4 nM) conditions. Nitrogenase activities for strain JH359 and for the wild-type strain in free-living culture were both strongly inhibited by tungsten; thus, the nitrogenase activities of both strains are probably the result of a "conventional" Mo-containing nitrogenase. Soybeans inoculated with strain JH359 and grown under either Mo-supplemented or Mo-deficient conditions had greater specific acetylene reduction rates and significantly greater plant fresh weight than those inoculated with the wild-type strain. Under Mo-deficient conditions, the acetylene reduction rates and plant fresh weights were up to 35 and 58% greater, respectively, for mutant-nodulated plants compared with wild-type-strain-nodulated plants.