The Collaborative Aging Research Using Technology Initiative: An Open, Sharable, Technology-Agnostic Platform for the Research Community

Introduction

Future digital health research hinges on methodologies to conduct remote clinical assessments and in-home monitoring. The Collaborative Aging Research Using Technology (CART) initiative was introduced to establish a digital technology research platform that could widely assess activity in the homes of diverse cohorts of older adults and detect meaningful change longitudinally. This paper reports on the built end-to-end design of the CART platform, its functionality, and the resulting research capabilities.

Methods

CART platform development followed a principled design process aiming for scalability, use case flexibility, longevity, and data privacy protection while allowing sharability. The platform, comprising ambient technology, wearables, and other sensors, was deployed in participants' homes to provide continuous, long-term (months to years), and ecologically valid data. Data gathered from CART homes were sent securely to a research server for analysis and future data sharing.

Results

The CART system was created, iteratively tested, and deployed to 232 homes representing four diverse cohorts (African American, Latinx, low-income, and predominantly rural-residing veterans) of older adults (n = 301) across the USA. Multiple measurements of wellness such as cognition (e.g., mean daily computer use time = 160-169 min), physical mobility (e.g., mean daily transitions between rooms = 96-155), sleep (e.g., mean nightly sleep duration = 6.3-7.4 h), and level of social engagement (e.g., reports of overnight visitors = 15-45%) were collected across cohorts.

Conclusion

The CART initiative resulted in a minimally obtrusive digital health-enabled system that met the design principles while allowing for data capture over extended periods and can be widely used by the research community. The ability to monitor and manage health digitally within the homes of older adults is an important alternative to in-person assessments in many research contexts. Further advances will come with wider, shared use of the CART system in additional settings, within different disease contexts, and by diverse research teams.

Sex and genetic differences in postoperative cognitive dysfunction: a longitudinal cohort analysis

BACKGROUND

Postoperative cognitive dysfunction (POCD) is a common postoperative complication experienced by patients aged 65 years and older, and these older adults comprise more than one third of the surgical patients in the USA. Because not everyone with a history of exposure to surgery and anesthesia develops POCD, there are likely major biological risk factors involved. There are important gaps in our knowledge regarding whether genetic makeup, biological sex, or other Alzheimer's disease risk factors predispose older adults to developing POCD. We set out to determine whether biological sex and Apolipoprotein E-ε4 (APOE4) carrier status increase the risk of developing POCD in older adults.

METHODS

We performed a cohort analysis of 1033 participants of prospective longitudinal aging studies. Participants underwent regular cognitive test batteries and we compared the annual rate of change over time in various cognitive measures in the women exposed to surgery and general anesthesia compared to the men exposed to surgery and general anesthesia. Mixed-effects statistical models were used to assess the relationship between biological sex, APOE4 carrier status, surgery and anesthesia exposure, and the rate of change in cognitive test scores.

RESULTS

When comparing all men (n = 89) and women (n = 164) who had surgery, there were no significant sex differences in postoperative cognitive outcomes. However, men with an APOE4 allele performed significantly worse on cognitive testing following surgery and anesthesia than women APOE4 carriers, even after adjusting for age, education level, and comorbidities.

CONCLUSIONS

Older men with APOE4 allele may be more vulnerable to postoperative cognitive dysfunction than older women with APOE4 allele.

Surgery is associated with ventricular enlargement as well as cognitive and functional decline

INTRODUCTION

In preclinical studies, surgery/anesthesia contribute to cognitive decline and enhance neuropathologic changes underlying Alzheimer's disease (AD). Nevertheless, the link between surgery, anesthesia, apolipoprotein E ε4 (APOE ε4), and AD remains unclear.

METHODS

We performed a retrospective cohort analysis of two prospective longitudinal aging studies. Mixed-effects statistical models were used to assess the relationship between surgical/anesthetic exposure, the APOE genotype, and rate of change in measures of cognition, function, and brain volumes.

RESULTS

The surgical group (n = 182) experienced a more rapid rate of deterioration compared with the nonsurgical group (n = 345) in several cognitive, functional, and brain magnetic resonance imaging measures. Furthermore, there was a significant synergistic effect of anesthesia/surgery exposure and presence of the APOE ε4 allele in the decline of multiple cognitive and functional measures.

DISCUSSION

These data provide insight into the role of surgical exposure as a risk factor for cognitive and functional decline in older adults.

Associations between observed in-home behaviors and self-reported low mood in community-dwelling older adults

OBJECTIVES

To ascertain the association between self-report of low mood and unobtrusively measured behaviors (walking speed, time out of residence, frequency of room transitions, and computer use) in community-dwelling older adults using novel monitoring technologies.

DESIGN

Longitudinal cohort study of older adults whose homes were outfitted with activity sensors. Participants completed Internet-based weekly health questionnaires with questions about mood.

SETTING

Apartments and homes of older adults living in the Portland, Oregon, metropolitan area.

PARTICIPANTS

Adults, average age 84, followed for an average of 3.7 years (n = 157).

MEASUREMENTS

Mood was assessed according to self-report each week. Walking speed, time spent out of residence, and room transitions were estimated using data from sensors; computer use was measured by timing actual use. The association between global or weekly low mood and the four behavior measures was ascertained, adjusting for baseline characteristics.

RESULTS

Eighteen thousand nine hundred sixty weekly observations of mood were analyzed; 2.6% involved low mood. Individuals who reported low mood more often had no average differences in any behavior parameters from those who reported low mood less often. During weeks when they reported low mood, participants spent significantly less time out of residence and on the computer but showed no change in walking speed or room transitions.

CONCLUSION

Low mood in these community-dwelling older adults involved going out of the house less and using the computer less but no consistent changes in movements. Technologies to monitor in-home behavior may have potential for research and clinical care.

Social activity decreases risk of placement in a long-term care facility for a prospective sample of community-dwelling older adults

The purpose of this study was to determine the role of modifiable factors in the risk of long-term care (LTC) placement. Using data from a cohort of community-residing older adults (N = 189), a secondary analysis was conducted of the contribution of social activity, sleep disturbances, and depressive symptoms to the risk of LTC placement. Analyses controlled for cognitive and functional impairment, age, and medical conditions. Within 5 years, 20% of participants were placed in a LTC facility. Each unit increase in social activity was associated with a 24% decrease in the risk of placement (odds ratio [OR] = 0.763, p = 0.001, 95% confidence interval [CI] [0.65, 0.89]). Cognitive impairment (OR = 3.05, p = 0.017, 95% CI [1.23, 7.59]), medical conditions (OR = 1.22, p = 0.039, 95% CI [1.01, 1.47]), and age (OR = 1.101, p = 0.030, 95% CI [1.01, 1.20]) were also significant individual predictors of placement. Although many of the strongest risk factors for placement are not modifiable, older adults who engage in more social activity outside the home may be able to delay transition from independent living.

Computer-related self-efficacy and anxiety in older adults with and without mild cognitive impairment

BACKGROUND

This study examines differences in computer-related self-efficacy and anxiety in subgroups of older adults, and changes in those measures after exposure to a systematic training program and subsequent computer use.

METHODS

Participants were volunteers in the Intelligent Systems for Assessment of Aging Changes study (ISAAC) carried out by the Oregon Center for Aging and Technology. Participants were administered two questionnaires before training and again 1 year later, which were related to computer self-efficacy and anxiety. Continuous recording of computer use was also assessed for a subset of participants.

RESULTS

Baseline comparisons by sex, age, education, living arrangement, and computer proficiency, but not cognitive status, yielded significant differences in confidence and anxiety related to specific aspects of computer use. At 1-year follow-up, participants reported less anxiety and greater confidence. However, the benefits of training and exposure varied by group and task. Comparisons based on cognitive status showed that the cognitively intact participants benefited more from training and/or experience with computers than did participants with mild cognitive impairment (MCI), who after 1 year continued to report less confidence and more anxiety regarding certain aspects of computer use.

CONCLUSION

After 1 year of consistent computer use, cognitively intact participants in this study reported reduced levels of anxiety and increased self-confidence in their ability to perform specific computer tasks. Participants with MCI at baseline were less likely to demonstrate increased efficacy or confidence than their cognitively intact counterparts.

In-home walking speeds and variability trajectories associated with mild cognitive impairment

OBJECTIVE

To determine whether unobtrusive long-term in-home assessment of walking speed and its variability can distinguish those with mild cognitive impairment (MCI) from those with intact cognition.

METHODS

Walking speed was assessed using passive infrared sensors fixed in series on the ceiling of the homes of elderly individuals participating in the Intelligent Systems for Assessing Aging Change (ISAAC) cohort study. Latent trajectory models were used to analyze weekly mean speed and walking speed variability (coefficient of variation [COV]).

RESULTS

ISAAC participants living alone included 54 participants with intact cognition, 31 participants with nonamnestic MCI (naMCI), and 8 participants with amnestic MCI at baseline, with a mean follow-up of 2.6 ± 1.0 years. Trajectory models identified 3 distinct trajectories (fast, moderate, and slow) of mean weekly walking speed. Participants with naMCI were more likely to be in the slow speed group than in the fast (p = 0.01) or moderate (p = 0.04) speed groups. For COV, 4 distinct trajectories were identified: group 1, the highest baseline and increasing COV followed by a sharply declining COV; groups 2 and 3, relatively stable COV; and group 4, the lowest baseline and decreasing COV. Participants with naMCI were more likely to be members of either highest or lowest baseline COV groups (groups 1 or 4), possibly representing the trajectory of walking speed variability for early- and late-stage MCI, respectively.

CONCLUSION

Walking speed and its daily variability may be an early marker of the development of MCI. These and other real-time measures of function may offer novel ways of detecting transition phases leading to dementia.

Executive function predicts risk of falls in older adults without balance impairment

Background

Executive dysfunction has previously been found to be a risk factor for falls. The aim of this study is to investigate the association between executive dysfunction and risk of falling and to determine if this association is independent of balance.

Methods

Participants were 188 community-dwelling individuals aged 65 and older. All participants underwent baseline and annual evaluations with review of health history, standardized neurologic examination, neuropsychological testing, and qualitative and quantitative assessment of motor function. Falls were recorded prospectively using weekly online health forms.

Results

During 13 months of follow-up, there were 65 of 188 participants (34.6%) who reported at least one fall. Univariate analysis showed that fallers were more likely to have lower baseline scores in executive function than non-fallers (p = 0.03). Among participants without balance impairment we found that higher executive function z-scores were associated with lower fall counts (p = 0.03) after adjustment for age, sex, health status and prior history of falls using negative binomial regression models. This relationship was not present among participants with poor balance.

Conclusions

Lower scores on executive function tests are a risk factor for falls in participants with minimal balance impairment. However, this effect is attenuated in individuals with poor balance where physical or more direct motor systems factors may play a greater role in fall risk.

Prevalence of complicated gastroesophageal reflux disease and Barrett's esophagus among racial groups in a multi-center consortium

AIMS

The Clinical Outcomes Research Initiative database was used to evaluate ethnic trends in complicated reflux disease and suspected Barrett's esophagus among various racial groups.

METHODS

Endoscopic findings for procedures performed January 2000-December 2005 for any indication and for reflux-related indications were reviewed by racial group.

RESULTS

Of 280,075 procedures examined, Hispanics were the most likely to have esophagitis (Hispanic 19.6%, white 17.3%, black 15.8%, Asian/Pacific Islander 9.5%, P-value<0.0001), and white subjects were most likely to have suspected BE (white 5.0%, Hispanic 2.9%, Asian/Pacific Islander 1.8%, black 1.5%, P-value<0.0001). Endoscopies performed for reflux-related indications had similar trends for esophagitis and esophageal stricture. Among reflux/Barrett's screening procedures adjusted for age and gender, Hispanics were most likely to have esophagitis (OR=1.28, P-value<0.0001) compared to Caucasians.

CONCLUSION

Our results demonstrate an association of suspected Barrett's esophagus and stricture with white patients and esophagitis with Hispanic patients. These findings need to be followed-up with further study.

The value of traditional upper endoscopy as a diagnostic test for Barrett's esophagus

BACKGROUND

The standard test for diagnosing Barrett's esophagus (BE) is a conventional upper endoscopy. However, studies have shown that confirmation of BE by endoscopy with histologic intestinal metaplasia can be difficult.

OBJECTIVE

To determine the overall accuracy, as well as factors that influence the accuracy of a conventional upper endoscopy in diagnosing BE.

SETTING

Thirteen academic, community, and Veterans Affairs sites.

DESIGN

A retrospective data review.

PATIENTS

Patients who underwent an upper endoscopy with a finding of "suspected Barrett's esophagus" and esophageal biopsies. Pathology reports were examined to identify cases with intestinal metaplasia.

MAIN OUTCOME MEASUREMENTS

Percentage of pathology-confirmed BE among suspected cases.

RESULTS

A total of 2511 procedures were examined; the frequency of biopsy-confirmed BE was 48.4%. Multivariate logistic regression identified the following factors to be independently associated with biopsy-confirmed BE: long-segment BE that measured > or = 3 cm (odds ratio [OR] 4.61 [95% CI, 3.73-5.69]), male sex (OR 1.82 [95% CI, 1.49-2.22]), increasing age (age interval 70-79 years with OR 2.33 compared with age <50 years [95% CI, 1.75-3.10]), the presence of a hiatal hernia (OR 1.46 [95% CI, 1.22-1.84]), and white race (OR 1.90 [95% CI, 1.49-2.22]).

LIMITATIONS

Biopsy specimens were assumed to sample the tubular esophagus; the actual pathology slides were not reevaluated by the investigators.

CONCLUSIONS

Endoscopic evaluation has limitations for the diagnosis of BE. Specific patient and endoscopic characteristics may be associated with the confirmation of BE on biopsy specimens. Further study is needed to determine if new endoscopic imaging technologies improve the ability to correctly identify BE.

Variation in practice of ileal intubation among diverse endoscopy settings: results from a national endoscopic database

BACKGROUND

Terminal ileum intubation rates at colonoscopy are variable. One of the major indications for terminal ileum intubation is to identify Crohn's disease. Signs and symptoms which raise a suspicion of Crohn's include abdominal pain/bloating, anaemia and diarrhoea.

AIM

To determine the proportion of terminal ileal intubation in patients undergoing evaluation of abdominal pain/bloating, anaemia or diarrhoea with normal endoscopic findings at colonoscopy.

METHODS

The Clinical Outcomes Research Initiative national endoscopic database was analysed to determine the proportion of terminal ileum intubation in patients undergoing evaluation of either abdominal pain/bloating, anaemia or diarrhoea with normal endoscopic findings at colonoscopy and to characterize this population of patients. Patients with known or suspected inflammatory bowel disease were excluded from the analysis.

RESULTS

Between January 2000 and December 2003, 21 638 patients underwent complete colonoscopy for evaluation of either abdominal pain/bloating, anaemia or diarrhoea with normal colon findings. Overall, 3858 patients (18%) underwent terminal ileum evaluation. Intubation rates differed according to procedure indication: abdominal pain (13%), anaemia (13%), diarrhoea (28%). Terminal ileum assessment declined with advancing patient age and was least frequent in Black patients (12% vs. 18% in non-Blacks, P < 0.0001). Ileal intubation rates also varied among endoscopy site types: community (17%), academic (21%), Veterans Affairs Medical Centres (17%), P < 0.0001. Multiple logistic regression identified patients with the indication of diarrhoea (OR: 2.58) as more likely to undergo terminal ileum intubation when compared with those with abdominal pain/bloating. Patients in Veterans Affairs (OR: 1.26) and academic (OR: 1.29) sites were more likely to undergo terminal ileum intubation compared with community sites.

CONCLUSION

Less than one-fifth of patients with either abdominal pain/bloating, anaemia or diarrhoea underwent ileal intubation in the setting of a normal colonoscopy. Significant practice variation was observed in rates of terminal ileum evaluation. Further study is required to determine whether terminal ileum examination impacts patient management or outcome.

Colonic biopsy practice for evaluation of diarrhea in patients with normal endoscopic findings: results from a national endoscopic database

BACKGROUND

The colonic biopsy is the only reliable method for identification of microscopic colitis in patients with chronic diarrhea and normal endoscopic findings.

METHODS

The Clinical Outcomes Research Initiative national endoscopic database was analyzed to determine the rate at which colonic biopsy specimens were obtained in patients undergoing colonoscopy for the evaluation of diarrhea with no visible mucosal abnormality.

RESULTS

Between January 2000 and December 2003, 5565 unique adult patients underwent colonoscopy for evaluation of diarrhea without detection of any mucosal abnormality. Colonic mucosal biopsy specimens were obtained in 4410 (79.2%) of these patients. The rates at which biopsy specimens were obtained differed among the sites where colonoscopy was performed; biopsy specimens were obtained from more patients undergoing colonoscopy in university-affiliated settings (86.8%) compared with Veterans Affairs Medical Centers (VAMC) (78.5%) or community sites (78.6%) ( p < 0.001). On multivariate analysis, biopsy specimens were more likely to be obtained in younger patients (OR 0.7: 95%CI[0.6, 0.8] for age >50 years vs. <50 years), women patients (OR 1.4: 95% CI[1.2, 1.6] in community setting; OR 4.1: 95% CI[1.6, 10.5] in VAMC setting), and patients seen in university-affiliated medical centers (university center OR 2.1: 95% CI[1.5, 3.0] vs. community setting).

CONCLUSIONS

Biopsy specimens are obtained in four fifths of patients with diarrhea and normal colonoscopy findings to exclude microscopic colitis. Variation in biopsy practice exists among endoscopy site types and by gender. Clear guidelines are needed for the endoscopic approach to these patients.

A phase I study of 5-fluorouracil, leucovorin, and celecoxib in patients with incurable colorectal cancer

A phase I study of fixed-dose 5-fluorouracil (FU) and leucovorin (LCV), with excalating doses of the selective cyclooxygenase-2 (COX-2) inhibitor celecoxib, was conducted in 16 patients with advanced colorectal adenocarcinoma. At doses typically used to treat arthritis patients (100-200 mg po BID), celecoxib did not increase toxicities expected from the chemotherapy alone. 5-FU and leucovorin did not affect COX-2 inhibition by celecoxib. Preliminary data suggest it is safe to combine celecoxib with standard chemotherapeutic agents, in treatment of patients with colorectal cancer.