Methodology for Establishing a Community-Wide Life Laboratory for Capturing Unobtrusive and Continuous Remote Activity and Health Data.

An end-to-end suite of technologies has been established for the unobtrusive and continuous monitoring of health and activity changes occurring in the daily life of older adults over extended periods of time. The technology is aggregated into a system that incorporates the principles of being minimally obtrusive, while generating secure, privacy protected, continuous objective data in real-world (home-based) settings for months to years. The system includes passive infrared presence sensors placed throughout the home, door contact sensors installed on exterior doors, connected physiological monitoring devices (such as scales), medication boxes, and wearable actigraphs. Driving sensors are also installed in participants' cars and computer (PC, tablet or smartphone) use is tracked. Data is annotated via frequent online self-report options that provide vital information with regard to the data that is difficult to infer via sensors such as internal states (e.g., pain, mood, loneliness), as well as data referent to activity pattern interpretation (e.g., visitors, rearranged furniture). Algorithms have been developed using the data obtained to identify functional domains key to health or disease activity monitoring, including mobility (e.g., room transitions, steps, gait speed), physiologic function (e.g., weight, body mass index, pulse), sleep behaviors (e.g., sleep time, trips to the bathroom at night), medication adherence (e.g., missed doses), social engagement (e.g., time spent out of home, time couples spend together), and cognitive function (e.g., time on computer, mouse movements, characteristics of online form completion, driving ability). Change detection of these functions provides a sensitive marker for the application in health surveillance of acute illnesses (e.g., viral epidemic) to the early detection of prodromal dementia syndromes. The system is particularly suitable for monitoring the efficacy of clinical interventions in natural history studies of geriatric syndromes and in clinical trials.

Web-enabled Conversational Interactions as a Means to Improve Cognitive Functions: Results of a 6-Week Randomized Controlled Trial.

INTRODUCTION: Increasing social interaction could be a promising intervention for improving cognitive function. We examined the feasibility of a randomized controlled trial to assess whether conversation-based cognitive stimulation, through personal computers, webcams, and a user-friendly interactive Internet interface had high adherence and a positive effect on cognitive functions among older adults without dementia. METHODS: Daily 30 minute face-to-face communications were conducted over a 6-week trial period in the intervention group. The control group had only a weekly telephone interview. Cognitive status of normal and MCI subjects was operationally defined as Global Clinical Dementia Rating (CDR) = 0 and 0.5, respectively. Age, sex, education, Mini-Mental State Exam and CDR score were balancing factors in randomization. Subjects were recruited using mass-mailing invitations. Pre-post differences in cognitive test scores and loneliness scores were compared between control and intervention groups using linear regression models. RESULTS: Eighty-three subjects participated (intervention: n=41, control: n=42). Their mean (std) age was 80.5 (6.8) years. Adherence to the protocol was high; there was no dropout and mean % of days completed out of the targeted trial days among the intervention group was 89% (range: 77%-100%). Among the cognitively intact participants, the intervention group improved more than the control group on a semantic fluency test (p=0.003) at the post-trial assessment and a phonemic fluency test (p=0.004) at the 18th week assessments. Among those with MCI, a trend (p=0.04) of improved psychomotor speed was observed in the intervention group. DISCUSSION: Daily conversations via user-friendly Internet communication programs demonstrated high adherence. Among cognitively intact, the intervention group showed greater improvement in tests of language-based executive functions. Increasing daily social contacts through communication technologies could offer cost-effective home-based preventions. Further studies with a longer duration of follow-up are required to examine whether the intervention slows cognitive declines and delays the onset of dementia.

Social Markers of Mild Cognitive Impairment: Proportion of Word Counts in Free Conversational Speech.

BACKGROUND: Detecting early signs of Alzheimer's disease (AD) and mild cognitive impairment (MCI) during the pre-symptomatic phase is becoming increasingly important for costeffective clinical trials and also for deriving maximum benefit from currently available treatment strategies. However, distinguishing early signs of MCI from normal cognitive aging is difficult. Biomarkers have been extensively examined as early indicators of the pathological process for AD, but assessing these biomarkers is expensive and challenging to apply widely among pre-symptomatic community dwelling older adults. Here we propose assessment of social markers, which could provide an alternative or complementary and ecologically valid strategy for identifying the pre-symptomatic phase leading to MCI and AD. METHODS: The data came from a larger randomized controlled clinical trial (RCT), where we examined whether daily conversational interactions using remote video telecommunications software could improve cognitive functions of older adult participants. We assessed the proportion of words generated by participants out of total words produced by both participants and staff interviewers using transcribed conversations during the intervention trial as an indicator of how two people (participants and interviewers) interact with each other in one-on-one conversations. We examined whether the proportion differed between those with intact cognition and MCI, using first, generalized estimating equations with the proportion as outcome, and second, logistic regression models with cognitive status as outcome in order to estimate the area under ROC curve (ROC AUC). RESULTS: Compared to those with normal cognitive function, MCI participants generated a greater proportion of words out of the total number of words during the timed conversation sessions (p=0.01). This difference remained after controlling for participant age, gender, interviewer and time of assessment (p=0.03). The logistic regression models showed the ROC AUC of identifying MCI (vs. normals) was 0.71 (95% Confidence Interval: 0.54 - 0.89) when average proportion of word counts spoken by subjects was included univariately into the model. CONCLUSION: An ecologically valid social marker such as the proportion of spoken words produced during spontaneous conversations may be sensitive to transitions from normal cognition to MCI.

Characteristics associated with willingness to participate in a randomized controlled behavioral clinical trial using home-based personal computers and a webcam.

BACKGROUND: Trials aimed at preventing cognitive decline through cognitive stimulation among those with normal cognition or mild cognitive impairment are of significant importance in delaying the onset of dementia and reducing dementia prevalence. One challenge in these prevention trials is sample recruitment bias. Those willing to volunteer for these trials could be socially active, in relatively good health, and have high educational levels and cognitive function. These participants' characteristics could reduce the generalizability of study results and, more importantly, mask trial effects. We developed a randomized controlled trial to examine whether conversation-based cognitive stimulation delivered through personal computers, a webcam and the internet would have a positive effect on cognitive function among older adults with normal cognition or mild cognitive impairment. To examine the selectivity of samples, we conducted a mass mail-in survey distribution among community-dwelling older adults, assessing factors associated with a willingness to participate in the trial. METHODS: Two thousand mail-in surveys were distributed to retirement communities in order to collect data on demographics, the nature and frequency of social activities, personal computer use and additional health-related variables, and interest in the prevention study. We also asked for their contact information if they were interested in being contacted as potential participants in the trial. RESULTS: Of 1,102 surveys returned (55.1% response rate), 983 surveys had complete data for all the variables of interest. Among them, 309 showed interest in the study and provided their contact information (operationally defined as the committed with interest group), 74 provided contact information without interest in the study (committed without interest group), 66 showed interest, but provided no contact information (interest only group), and 534 showed no interest and provided no contact information (no interest group). Compared with the no interest group, the committed with interest group were more likely to be personal computer users (odds ratio (OR) = 2.78), physically active (OR = 1.03) and had higher levels of loneliness (OR = 1.16). CONCLUSION: Increasing potential participants' familiarity with a personal computer and the internet before trial recruitment could increase participation rates and improve the generalizability of future studies of this type. TRIAL REGISTRATION: The trial was registered on 29 March 2012 at ClinicalTirals.gov (ID number NCT01571427).

Effectiveness of aquaflor (50% florfenicol) to control mortality associated with Streptococcus iniae in freshwater-reared subadult sunshine bass.

We conducted a field trial to evaluate the effectiveness of Aquaflor (50% florfenicol) for controlling mortality associated with Streptococcus iniae in freshwater-reared subadult sunshine bass (female white bass Morone chrysops X male striped bass M. saxatilis). Bacterial samples collected from moribund fish representing a reference population were presumptively identified microbiologically and were later confirmed to be S. iniae by biochemical characterization and polymerase chain reaction. The trial comprised a 1-d acclimation period, 10-d treatment period, and 14-d posttreatment period. During the treatment period, Aquaflor-medicated feed was administered to treated tanks (N = 3) at a target dose of 10 mg of florfenicol x kg of fish(-1) x d(-1), and nonmedicated feed was administered to control tanks (N = 3). At the end of the posttreatment period, mean (+/- SD) cumulative mortality in treated tanks (9 +/- 11%) was significantly (P = 0.040) less than that in control tanks (52 +/- 13%). Analysis of medicated feed samples revealed that treated tanks had received an actual dose of 8.3 mg florfenicol x kg fish(-1) x d(-1) (83% of target). No florfenicol was detected in control feed samples. Although the actual florfenicol dose administered to treated tanks was less than the target dose, the trial was accepted by the U.S. Food and Drug Administration Center for Veterinary Medicine as demonstrating the efficacy of Aquaflor to control mortality associated with S. iniae in cultured sunshine bass populations.