Attitudes toward clinical trials across the Alzheimer's disease spectrum

Recruitment of pre-dementia participants: main enrollment barriers in a longitudinal amyloid-PET study

BACKGROUND

The mismatch between the limited availability versus the high demand of participants who are in the pre-dementia phase of Alzheimer's disease (AD) is a bottleneck for clinical studies in AD. Nevertheless, potential enrollment barriers in the pre-dementia population are relatively under-reported. In a large European longitudinal biomarker study (the AMYPAD-PNHS), we investigated main enrollment barriers in individuals with no or mild symptoms recruited from research and clinical parent cohorts (PCs) of ongoing observational studies.

METHODS

Logistic regression was used to predict study refusal based on sex, age, education, global cognition (MMSE), family history of dementia, and number of prior study visits. Study refusal rates and categorized enrollment barriers were compared between PCs using chi-squared tests.

RESULTS

535/1856 (28.8%) of the participants recruited from ongoing studies declined participation in the AMYPAD-PNHS. Only for participants recruited from clinical PCs (n = 243), a higher MMSE-score (β =  - 0.22, OR = 0.80, p < .05), more prior study visits (β =  - 0.93, OR = 0.40, p < .001), and positive family history of dementia (β = 2.08, OR = 8.02, p < .01) resulted in lower odds on study refusal. General study burden was the main enrollment barrier (36.1%), followed by amyloid-PET related burden (PCresearch = 27.4%, PCclinical = 9.0%, X2 = 10.56, p = .001), and loss of research interest (PCclinical = 46.3%, PCresearch = 16.5%, X2 = 32.34, p < .001).

CONCLUSIONS

The enrollment rate for the AMYPAD-PNHS was relatively high, suggesting an advantage of recruitment via ongoing studies. In this observational cohort, study burden reduction and tailored strategies may potentially improve participant enrollment into trial readiness cohorts such as for phase-3 early anti-amyloid intervention trials. The AMYPAD-PNHS (EudraCT: 2018-002277-22) was approved by the ethical review board of the VU Medical Center (VUmc) as the Sponsor site and in every affiliated site.

Recruitment of older adult-caregiver dyads during the COVID-19 pandemic: an example from a study to evaluate a novel activities of daily living (ADL) sensor system

Under ideal circumstances, recruitment of older adult-caregiver dyads to dementia research is challenging. The COVID-19 pandemic introduced additional barriers to recruitment, necessitating swift adjustments to pre-pandemic recruitment strategies and schedules. This brief research report describes the challenges, yield, and cost of recruiting older adult-caregiver dyads to an 18-month observational research study during COVID-19. The study aimed to evaluate the effectiveness of a novel in-home sensor system at identifying cognitive change in older adults with Alzheimer's disease and related dementias (ADRD) through background monitoring of activities of daily living (ADL). Recruitment methods included flyers distributed alongside home-delivered meals, direct mailings, publicly available brochures, community presentations, periodical advertisements, and various other strategies. Of 510 inquiries, 117 older adult-caregiver dyads were enrolled at a total cost of ~$368,000, yielding an average per dyad recruiting cost of $3,148. Distributing flyers alongside home-delivered meals produced the most dyads (n = 46, 39%) and the least non-labor costs ($24.33) per enrolled dyad. Recruitment during the pandemic exceeded the pre-COVID-19 budget, but enrollment goals were nevertheless achieved through community-based methods. Our experience illustrates the challenge of recruiting older adult-caregiver dyads to dementia research and the value of trusted community partners in recruiting this population. Our strategies and recommendations may benefit researchers who plan to recruit community-based older adults and their caregivers for future dementia research.

Facilitators and Barriers to Older Adult Participation in Cancer Trials: A Qualitative Study Exploring Patient-Caregiver Dyad Congruence

PURPOSE

Family caregivers play an integral role in caring for older adults with cancer. Few studies have examined older adults with cancer and their family caregivers as a unit in a relationship or a dyad. Dyad congruence, or consistency in perspective, is relevant to numerous aspects of living with cancer, including the decision to enroll in a cancer clinical trial.

METHODS

Semistructured interviews of 32 older women (age ≥ 70 years) with breast cancer and their family caregivers (16 dyads) were conducted at both academic and community settings from December 2019 to March 2021 to explore perceived facilitators and barriers to cancer trials. Dyad congruence was defined as aligned (matching) perspectives, and incongruence was defined as misaligned (nonmatching) perspectives.

RESULTS

Five (31%) of 16 patients were age ≥80 years, 11 (69%) had nonmetastatic breast cancer, and 14 (88%) were treated in an academic setting. Six (38%) of 16 caregivers were in the 50-59 age group, 10 (63%) were female, and seven (44%) were daughters. Dyad congruence centered on the clinical benefit of trials and physician recommendation. However, compared with caregivers, patients were more motivated to contribute to science. Patients and caregivers also differed on the perceived extent to which the caregiver influenced enrollment.

CONCLUSION

Older patients with cancer and their caregivers generally agree about the facilitators and barriers to cancer trial enrollment, but some perceptions are misaligned. Further research is needed to understand whether misaligned perspectives between patients and caregivers influence clinical trial participation of older adults with cancer.

Research Attitude and Interest among Cancer Survivors with or without Cognitive Impairment

BACKGROUND

We examined the research attitudes and willingness to participate in clinical research among cancer survivors with varying degrees of cognitive function.

METHODS

This is a secondary analysis of data collected through the University of California Irvine Consent-to-Contact registry. Cancer survivors completed the Cognitive Function Instrument (CFI), the Research Attitudes Questionnaire (RAQ), and willingness to participate (WTP) in certain research procedures. Perceived cognitive impairment (CI) was defined as the worst 20% CFI scores.

RESULTS

Here, 265 CI and 909 cognitively non-impaired (CNI) participants' data were analyzed. Mean age and sex distribution were similar, with fewer non-Hispanic Whites and education years among CI participants. More CI participants self-reported past diagnoses of Alzheimer's disease, mild cognitive impairment, stroke, depression, post-traumatic stress disorder, and alcohol abuse (all p < 0.05). CI participants were significantly more interested in studies investigating approved medications (92% vs. 87%, p = 0.030), lumbar puncture (47% vs. 38%, p = 0.027), and autopsy (78% vs. 69%, p = 0.022). After removing survivors with co-existing neuropsychiatric conditions, interest in autopsy studies remained statistically higher among CI (79% vs. 69%, p = 0.022).

CONCLUSIONS

Participants with cancer and CI are open to research procedures and interventions that are traditionally less utilized, which may facilitate the discovery of the pathogenesis and interventions for cancer-related cognitive impairment (CRCI).

Centralizing prescreening data collection to inform data-driven approaches to clinical trial recruitment

BACKGROUND

Recruiting to multi-site trials is challenging, particularly when striving to ensure the randomized sample is demographically representative of the larger disease-suffering population. While previous studies have reported disparities by race and ethnicity in enrollment and randomization, they have not typically investigated whether disparities exist in the recruitment process prior to consent. To identify participants most likely to be eligible for a trial, study sites frequently include a prescreening process, generally conducted by telephone, to conserve resources. Collection and analysis of such prescreening data across sites could provide valuable information to improve understanding of recruitment intervention effectiveness, including whether traditionally underrepresented participants are lost prior to screening.

METHODS

We developed an infrastructure within the National Institute on Aging (NIA) Alzheimer's Clinical Trials Consortium (ACTC) to centrally collect a subset of prescreening variables. Prior to study-wide implementation in the AHEAD 3-45 study (NCT NCT04468659), an ongoing ACTC trial recruiting older cognitively unimpaired participants, we completed a vanguard phase with seven study sites. Variables collected included age, self-reported sex, self-reported race, self-reported ethnicity, self-reported education, self-reported occupation, zip code, recruitment source, prescreening eligibility status, reason for prescreen ineligibility, and the AHEAD 3-45 participant ID for those who continued to an in-person screening visit after study enrollment.

RESULTS

Each of the sites was able to submit prescreening data. Vanguard sites provided prescreening data on a total of 1029 participants. The total number of prescreened participants varied widely among sites (range 3-611), with the differences driven mainly by the time to receive site approval for the main study. Key learnings instructed design/informatic/procedural changes prior to study-wide launch.

CONCLUSION

Centralized capture of prescreening data in multi-site clinical trials is feasible. Identifying and quantifying the impact of central and site recruitment activities, prior to participants signing consent, has the potential to identify and address selection bias, instruct resource use, contribute to effective trial design, and accelerate trial enrollment timelines.

Experiences of and recommendations on clinical trial design in Alzheimer's disease from the participant's point of view: a mixed-methods study in two clinical trial centers in the Netherlands

INTRODUCTION

In the context of the development of pharmaceutical interventions, expectations and experiences of participants are essential. Their insights may be particularly helpful to address the challenges of recruiting and retaining participants for Alzheimer's disease (AD) clinical trials. We examined clinical trial participants' experiences to optimize trial design in Alzheimer's disease (AD).

METHOD

In this mixed-methods study, we included adults who participated in sponsor-initiated AD trials at Brain Research Center, a clinical trial organization in the Netherlands. Participants (N = 71, age 69 ± 6.5, 54%F, 19 cognitively normal (CN), 19 mild cognitive impairment (MCI), and 33 AD dementia) first completed an online survey. Diagnostic group differences were investigated using chi-square tests or one-way ANOVAs. Next, a subsample (N = 12; 8 = CN, 4 = MCI) participated in focus groups to gain in-depth insight into their opinions on optimizing trial design from a participants' point of view. Audio recordings from focus group interviews were transcribed verbatim and analyzed by thematic content analysis by two independent researchers.

RESULTS

Most reported motives for enrolment included "to benefit future generations" (89%), followed by "for science" (66%) and "better monitoring" (42%). Frequent suggestions for increasing willingness to participate included a smaller chance to receive placebo (n = 38, 54%), shorter travel times (n = 27, 38%), and sharing individual results of different assessments (n = 57, 80%), as well as receiving trial results (n = 52, 73). Highest visual analogue burden scores (0-100) were found for the lumbar puncture (M = 47.2, SD = 38.2) and cognitive assessments (M = 27.2, SD = 25.7). Results did not differ between diagnostic groups, nor between patient and caregiver participants (all p-values>.05). Two additional themes emerged from the focus groups: "trial design," such as follow-up visit(s) after participating, and "trial center," including the relevance of a professional and empathic staff.

CONCLUSION

Relevant factors include expectation management and careful planning of high-burden assessments, provision of individual feedback, and prioritizing professionalism and empathy throughout conduct of the trial. Our findings provide insight into participants' priorities to increase willingness to participate and can be used to optimize trial success.

Barriers and facilitators to participating in Alzheimer's disease biomarker research in black and white older adults

Introduction

The study examined Black and White prospective participants' views of barriers to and facilitators of participation in Alzheimer's disease (AD) biomarker research.

Methods

In a mixed-methods study, 399 community-dwelling Black and White older adults (age ≥55) who had never participated in AD research completed a survey about their perceptions of AD biomarker research. Individuals from lower socioeconomic and education backgrounds and Black men were over-sampled to address perspectives of traditionally under-represented groups. A subset of participants (n = 29) completed qualitative interviews.

Results

Most participants expressed interest in biomarker research (overall 69%). However, Black participants were comparatively more hesitant than White participants (28.9% vs 15.1%), were more concerned about study risks (28.9% vs 15.1%), and perceived multiple barriers to participating in brain scans. These results persisted even after adjusting for trust and perceived knowledge of AD. Information was a primary barrier (when absent) and incentive (when provided) for AD biomarker research participation. Black older adults desired more information about AD (eg, risk, prevention), general research processes, and specific biomarker procedures. They also desired return of results to make informed decisions about their health, research-sponsored community awareness events, and for researchers to mitigate the burden placed on participants in research (eg, transportation, basic needs).

Conclusion

Our findings increase representativeness in the literature by focusing on individuals with no history of AD research experience and those from traditionally underrepresented groups in research. Results suggest that the research community needs to improve information sharing and raising awareness, increase their presence in the communities of underrepresented groups, reduce incidental costs, and provide valuable personal health information to participants to increase interest. Specific recommendations for improving recruitment are addressed. Future studies will assess the implementation of evidence-based, socioculturally sensitive recruitment strategies to increase enrollment of Black older adults into AD biomarker studies.HIGHLIGHTS: Individuals from under-represented groups are interested in Alzheimer's disease (AD) biomarker research.After adjusting for trust and AD knowledge, Black participants were still more hesitant.Information is a barrier (when absent) to and incentive (when given) for biomarker studies.Reducing burden (e.g., transportation) is essential for recruiting Black older adults.

Could Temperamental Features Modulate Participation in Clinical Trials?

The prodromal stages of Alzheimer's disease (AD) are the primary focus of research aimed at slowing disease progression. This study explores the influence of affective temperament on the motivation of people with mild cognitive impairment (MCI) and subjective cognitive decline (SCD) to participate in clinical trials. One hundred four subjects with MCI and SCD were screened for participation in pharmacological and non-pharmacological trials. Affective temperament was assessed based on the Temperament Evaluation of the Memphis, Pisa, Paris and San Diego (TEMPS) scale. Demographic variables and temperament subscales scores were compared between MCI and SCD patients and among patients participating in the pharmacological trial, the non-pharmacological trial and refusing participation. Twenty-one subjects consented to participate in the pharmacological trial, seventy consented to the non-pharmacological trial and thirteen refused to participate in any trial. Patients with SCD had greater education and more depressive temperamental traits than those with MCI. While older age, higher education and anxious temperament were negatively associated with participation in the pharmacological trial, irritable temperamental positively predicted pharmacological trial participation. In conclusion, temperamental features may affect the willingness of patients with MCI and SCD to take part in clinical trials and, especially, the choice to participate in pharmacological studies.

Recruiting Persons with Dementia and Caregivers in a Clinical Trial: Dyads Perceptions

Recruitment for dementia research is challenging and costly. Using Ajzen's Theory of Planned Behavior we explored attitudes, perceived norms, and perceived behavioral control of persons living with dementia (PLWD) and their caregivers who participated in one clinical trial to better understand factors that influence dyads' decisions to enroll. We conducted semi-structured telephone interviews with 12 PLWD and 9 caregivers and utilized directed content analysis. Categories connected with positive attitudes about study enrollment were personal desires of wanting to learn and in-person meetings with knowledgeable staff. Additionally, participants said the money always helps in terms of the financial incentive. Participants reported enrolling to support another person (perceived norm). Study requirements were thought to be easy (perceived behavioral control). Participants highlighted the importance of flexible scheduling and study tasks being completed at their home. Findings can inform future recruitment efforts and should be investigated as effective recruitment methods in other clinical trials.

Stakeholders' Perspectives regarding Participation in Neuromodulation-Based Dementia Intervention Research

This study evaluated stakeholders' perspectives regarding participation in two hypothetical neuromodulation trials focused on individuals with Alzheimer's disease and related disorders (ADRDs). Stakeholders (i.e., individuals at risk for ADRDs [n = 56], individuals with experience as a caregiver for someone with a cognitive disorder [n = 60], and comparison respondents [n = 124]) were recruited via MTurk. Primary outcomes were willingness to enroll (or enroll one's loved one), feeling lucky to have the opportunity to enroll, and feeling obligated to enroll in two protocols (transcranial magnetic stimulation, TMS; deep brain stimulation, DBS). Relative to the Comparison group, the At Risk group endorsed higher levels of "feeling lucky" regarding both research protocols, and higher willingness to participate in the TMS protocol. These findings provide tentative reassurance regarding the nature of decision making regarding neurotechnology-based research on ADRDs. Further work is needed to evaluate the full range of potential influences on research participation.

Experiences of Participation in a Multimodal Preventive Trial MIND-ADMINI Among Persons with Prodromal Alzheimer's Disease: A Qualitative Study

INTRODUCTION

Alzheimer's disease (AD) is one of the world's leading public health challenges. One-third of AD cases are attributable to modifiable vascular and lifestyle-related risk factors. The Multimodal Preventive Trial for Alzheimer's Disease, MIND-ADMINI a 6-month multinational parallel-group randomized controlled trial (RCT), targeted persons with prodromal AD and built on the positive outcomes from the Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) trial. The intervention consisted of four main components of (i) physical exercise training program, (ii) nutrition guidance, (iii) cognitive training, and (iv) social stimulation, as well as (iv) monitoring of metabolic/vascular risk factors.

AIM

The study aimed to explore and describe the experiences of participation in MIND-ADMINI among persons with prodromal AD.

METHODS

This qualitative study was part of the larger MIND-ADMINI project. Eight participants were interviewed twice, before and after the intervention. The data was analyzed using qualitative content analysis.

RESULTS

The results are presented as categories of (i) knowledge of AD and prevention, (ii) motives for study participation, (iii) experiences of the received information about the study, (iv) taking the decision to participate, (v) expectations on study participation, (vi) experiences of study participation and (vii) internal and external factors influencing study participation.

CONCLUSION

The MIND-ADMINI was well-tolerated by the participants. At the beginning of the study, the number of tasks and visits was perceived as burdensome but was later well-tolerated. The participant' knowledge about AD and prevention increased during the trial. Their motives for participating in MIND-ADMINI were described as both altruistic and self-beneficial. Health benefits from the study components, access to specialized medical care were identified as benefits. Managing the intensive flow of information was described a major challenge. The participants' needs for personalized support during the trial stress the importance of applying a person-centered approach providing the preventive trials.

Strategies Associated with Retaining Participants in the Longitudinal National Alzheimer's Coordinating Center Uniform Data Set Study

BACKGROUND

Best approaches for retaining research participants in Alzheimer's disease cohort studies are understudied.

OBJECTIVE

Using data from the National Alzheimer's Coordinating Center Uniform Data Set, we evaluated the associations of unique strategies with participant retention across Alzheimer's Disease Research Centers and explored potential effect modification by race, ethnicity and diagnostic group.

METHODS

We examined retention at the first follow-up visit among participants enrolled during 2015-2017. Structured surveys ascertained 95 retention tactics among 12 strategies. Strategy-specific summary scores were created based on the number of implemented tactics for each strategy and grouped into tertiles. Generalized estimating equations were constructed to evaluate associations between strategy scores and the odds of retention, controlling for age, sex, education, study partner type, marital status, visit length, battery length, diagnostic group, race and ethnicity. Separate models were stratified by race, ethnicity and diagnostic group. Effect modification was formally tested with interaction terms.

RESULTS

Among 5,715 total participants enrolled, 4,515 were Non-Hispanic White (79%), 335 were Hispanic/Latino (6%), 651 were Non-Hispanic Black (11%), and 214 were Non-Hispanic Asian (4%). Compared to the lowest tertile of scores, the highest tertile of scores involving improvement in study personnel and communication of study requirements and details were associated with 61% higher odds of retention in fully adjusted models (adjusted Odds Ratios [aOR] = 1.61, 95% Confidence Interval [CI] = 1.05-2.47 and aOR = 1.55, 95% CI = 1.03-2.35, respectively). We did not find evidence for effect modification.

CONCLUSION

In the setting of limited resources, specific retention strategies may be more valuable than others.

Effect of Aducanumab Approval on Willingness to Participate in Preclinical Alzheimer's Disease Trials

BACKGROUND

Clinical trials now test promising therapies in the preclinical stages of Alzheimer's disease (AD). Participant willingness to enroll in different types of preclinical AD trials is understudied and whether the FDA approval of aducanumab affected these attitudes is unknown.

OBJECTIVE

To evaluate preferences toward three preclinical AD trial scenarios and whether the FDA approval of aducanumab changed willingness to participate among potential trial participants.

METHODS

Through an electronic survey, we asked enrollees in a recruitment registry age 50-79 to rate their willingness (using a 6-point Likert scale) to enroll in three hypothetical preclinical AD trial scenarios: an in-clinic infused monoclonal antibody intervention, a home-infused monoclonal antibody intervention, and an oral BACE inhibitor intervention. We administered the survey before and after the FDA approval of aducanumab. We used a generalized estimating equation model to assess group differences in preference for the trial scenarios. We used a paired t-test to determine if willingness to participate (using total willingness across three scenarios as the outcome) changed after the FDA decision.

RESULTS

At baseline, the mean participant willingness was highest in the in-clinic infusion scenario. There was no significant change in willingness to participate, overall, after the FDA decision. Participants who were independently aware of the FDA's decision (prior to the second survey) demonstrated reduced willingness to participate; participants unaware of the FDA decision demonstrated no change.

CONCLUSION

Willingness to participate in preclinical AD trials may have been negatively affected by the FDA's decision to approve aducanumab among those aware of the decision.

Ethical aspects of facilitating the recruitment of people with dementia for clinical trials: A call for further debate

Under-representation of people with dementia in clinical research remains a significant obstacle to develop evidence-based practice guidelines and recommendation for dementia care and slows down the development of disease-modifying pharmacological interventions. This is partly due to the ethical challenges and complexities of recruiting people with dementia for clinical trials. The traditional approach adopted by research ethics committees and regulatory bodies has been to protect people with dementia as a vulnerable population from harms of participating in research. There are concerns that this approach is unduly rigid, precludes the conduct of necessary research, and has exclusionary, paternalistic and discriminatory ramifications. As such, there are increasing calls to shift to a new hybrid facilitative/protective approach. This paper identifies 4 strategies to operationalise the facilitative/protective approach in the context of dementia research. These are: (i) embedding dementia research in clinical care; (ii) increasing the recruitment of people at preclinical stages of dementia; (iii) streamlined proxy consent procedures; and (iv) advance research consent. I note that all 4 strategies hold the promise of facilitating the recruitment of people with dementia in clinical research. Nonetheless, they give rise to a diverse range of new ethical concerns and issues. This necessitates further scholarly work to explore possible ways to address the ethical concerns and issues arisen by the uptake of protective/facilitative approach. In particular, further research is necessary to clarify, to what extent, the said strategies ameliorate or increase the vulnerability of people with dementia.

Feasibility and acceptability evaluation of the Promoting Independence in Dementia (PRIDE) intervention for living well with dementia

OBJECTIVES

Post-diagnostic psychosocial interventions could play an important role in supporting people with mild dementia remain independent. The Promoting Independence in Dementia (PRIDE) intervention was developed to address this.

METHOD

The mixed methods non-randomized, pre-post feasibility study occurred across England. Facilitators were recruited from the voluntary sector and memory services. Participants and their supporters took part in the three-session intervention. Outcome measures were collected at baseline and follow-up. To evaluate acceptability, focus groups and interviews were conducted with a subsample of participants and facilitators.

RESULTS

Contextual challenges to delivery including national research governance changes, affected recruitment of study sites. Thirty-four dyads consented, with 14 facilitators providing the intervention. Dyads took part in at least two sessions (79%), and 73% in all three. Outcome measures were completed by 79% without difficulty, with minimal missing data. No significant changes were found on pre and post assessments. Post hoc analysis found moderate effect size improvements for self-management (SMAS instrument) in people with dementia (d = 0.41) and quality of life (EQ5D measure) in carers (d = 0.40). Qualitative data indicated that dyads found PRIDE acceptable, as did intervention facilitators.

CONCLUSIONS

The three-session intervention was well accepted by participant-dyads and intervention facilitators. A randomized controlled trial of PRIDE would need to carefully consider recruitment potential across geographically varied settings and site stratification according to knowledge of contextual factors, such as the diversity of post-diagnostic services across the country. Letting sites themselves be responsible for identifying suitable intervention facilitators was successful. The self-report measures showed potential to be included in the main trial.

Recruitment and retention of participant and study partner dyads in two multinational Alzheimer's disease registration trials

BACKGROUND

Early study exit is detrimental to statistical power and increases the risk for bias in Alzheimer's disease clinical trials. Previous analyses in early phase academic trials demonstrated associations between rates of trial incompletion and participants' study partner type, with participants enrolling with non-spouse study partners being at greater risk.

METHODS

We conducted secondary analyses of two multinational phase III trials of semagacestat, an oral gamma secretase inhibitor, for mild-to-moderate AD dementia. Cox's proportional hazards regression model was used to estimate the relationship between study partner type and the risk of early exit from the trial after adjustment for a priori identified potential confounding factors. Additionally, we used a random forest model to identify top predictors of dropout.

RESULTS

Among participants with spousal, adult child, and other study partners, respectively, 35%, 38%, and 36% dropped out or died prior to protocol-defined study completion, respectively. In unadjusted models, the risk of trial incompletion differed by study partner type (unadjusted p value = 0.027 for test of differences by partner type), but in models adjusting for potential confounding factors, the differences were not statistically significant (p value = 0.928). In exploratory modeling, participant age was identified as the primary characteristic to explain the relationship between study partner type and the risk of failing to complete the trial. Participant age was also the strongest predictor of trial incompletion in the random forest model.

CONCLUSIONS

After adjustment for age, no differences in the risk of incompletion were observed when comparing participants with different study partner types in these trials. Differences between our findings and the findings of previous studies may be explained by differences in trial phase, size, geographic regions, or the composition of academic and non-academic sites.

Feasibility and Preliminary Efficacy of an Internet-Delivered Intervention for Insomnia in Individuals with Mild Cognitive Impairment

BACKGROUND

Approximately 50% of older adults with cognitive impairment suffer from insomnia. When untreated, pre-existing cognitive problems may be exacerbated and potentially contribute to further cognitive decline. One promising approach to maintain cognitive health is to improve sleep quantity and quality.

OBJECTIVE

To determine feasibility, acceptability, and preliminary efficacy of Sleep Health Using the Internet for Older Adult Sufferers of Insomnia and Sleeplessness (SHUTi OASIS), an Internet-delivered cognitive behavioral therapy for insomnia (CBT-I) program in older adults with mild cognitive impairment (MCI).

METHODS

Older adults with MCI and insomnia were recruited from hospital-based memory and sleep disorders clinics and enrolled in a single-arm pilot study. Participants completed the six cores of SHUTi OASIS, over nine weeks with two-week baseline and post-assessments using self-reported sleep diaries. Feasibility and acceptability were informed by usage statistics and qualitative interviews; preliminary efficacy was informed by patient-generated sleep data.

RESULTS

Twelve participants enrolled and, on average, were 75.8 years of age. Ten participants completed the study and logged in most days. Most participants reported a positive overall experience, and interviews revealed successful and independent program management and completion. There were significant changes on all baseline to post-assessment sleep measures, including clinically meaningful improvements on the Insomnia Severity Index (13.5 to 8.3, p < 0.01), sleep efficiency, wake after sleep onset, and sleep onset latency (ps < 0.02). There was no statistically significant change in cognitive measures (p > 0.05).

CONCLUSION

This study supports that older adults with cognitive impairment can independently complete CBT-I via the Internet and achieve clinical sleep improvements.

Robust estimation in the nested case-control design under a misspecified covariate functional form

The Cox proportional hazards model is typically used to analyze time-to-event data. If the event of interest is rare and covariates are difficult or expensive to collect, the nested case-control (NCC) design provides consistent estimates at reduced costs with minimal impact on precision if the model is specified correctly. If our scientific goal is to conduct inference regarding an association of interest, it is essential that we specify the model a priori to avoid multiple testing bias. We cannot, however, be certain that all assumptions will be satisfied so it is important to consider robustness of the NCC design under model misspecification. In this manuscript, we show that in finite sample settings where the functional form of a covariate of interest is misspecified, the estimates resulting from the partial likelihood estimator under the NCC design depend on the number of controls sampled at each event time. To account for this dependency, we propose an estimator that recovers the results obtained using using the full cohort, where full covariate information is available for all study participants. We present the utility of our estimator using simulation studies and show the theoretical properties. We end by applying our estimator to motivating data from the Alzheimer's Disease Neuroimaging Initiative.

Racial and ethnic differences in older adults' willingness to be contacted about Alzheimer's disease research participation

INTRODUCTION

We sought to examine the association of race/ethnicity with willingness to engage in studies that involve procedures typical of Alzheimer's disease (AD) clinical trials and determine whether any observed differences could be explained by research attitudes.

METHODS

We studied 2749 adults aged ≥50 years who enrolled in a community-based recruitment registry.

RESULTS

Compared to non-Hispanic (NH) whites (n = 2393, 87%), Hispanics (n = 191, 7%), NH Asians (n = 129, 5%) and NH blacks (n = 36, 1%) were 44%, 46%, and 64% less willing, respectively, to be contacted for studies that have requirements typical of AD prevention trials, namely: cognitive testing, brain imaging, blood draws, and investigational medications. Mediation by research attitudes was explored, but did not explain the observed differences.

DISCUSSION

Our findings suggest that ethnoracial minorities are less willing to engage in studies that are typical of AD prevention trials. Future work should focus on understanding the factors that drive these differences.

Risks and benefits of unapproved disease-modifying treatments for neurodegenerative disease

OBJECTIVE

To determine whether patients randomized to unapproved, disease-modifying interventions in neurodegenerative disease trials have better outcomes than patients randomized to placebo by performing a systematic review and meta-analysis of risk and benefit experienced by patients in randomized placebo-controlled trials testing investigational treatments for Alzheimer disease, Parkinson disease, Huntington disease, or amyotrophic lateral sclerosis (ALS).

METHODS

We searched MEDLINE, Embase, and ClinicalTrials.gov for results of randomized trials testing non-Food and Drug Administration-approved, putatively disease-modifying interventions from January 2005 to May 2018. Trial characteristics were double-extracted. Coprimary endpoints were the treatment advantage over placebo on efficacy (standardized mean difference in outcomes) and safety (risk ratios of serious adverse events and withdrawals due to adverse events), calculated with random effects meta-analyses. The study was registered on PROSPERO (CRD42018103798).

RESULTS

We included 113 trials (n = 39,875 patients). There was no significant efficacy advantage associated with assignment to putatively disease-modifying interventions compared to placebo for Alzheimer disease (standardized mean difference [SMD] -0.03, 95% confidence interval [CI] -0.07 to 0.01), Parkinson disease (SMD -0.09, 95% CI -0.32 to 0.15), ALS (SMD 0.02, 95% CI -0.25 to 0.30), or Huntington disease (0.02, 95% CI -0.27 to 0.31). Patients with Alzheimer disease assigned to active treatment were at higher risk of experiencing serious adverse events (risk ratio [RR] 1.15, 95% CI 1.04-1.27) and withdrawals due to adverse events (RR 1.44, 95% CI 1.21-1.70).

CONCLUSIONS

Assignment to active treatment was not beneficial for any of the indications examined and may have been slightly disadvantageous for patients with Alzheimer disease. Our findings suggest that patients with neurodegenerative diseases are not, on the whole, harmed by assignment to placebo when participating in trials.

Prescreening for European Prevention of Alzheimer Dementia (EPAD) trial-ready cohort: impact of AD risk factors and recruitment settings

BACKGROUND

Recruitment is often a bottleneck in secondary prevention trials in Alzheimer disease (AD). Furthermore, screen-failure rates in these trials are typically high due to relatively low prevalence of AD pathology in individuals without dementia, especially among cognitively unimpaired. Prescreening on AD risk factors may facilitate recruitment, but the efficiency will depend on how these factors link to participation rates and AD pathology. We investigated whether common AD-related factors predict trial-ready cohort participation and amyloid status across different prescreen settings.

METHODS

We monitored the prescreening in four cohorts linked to the European Prevention of Alzheimer Dementia (EPAD) Registry (n = 16,877; mean ± SD age = 64 ± 8 years). These included a clinical cohort, a research in-person cohort, a research online cohort, and a population-based cohort. Individuals were asked to participate in the EPAD longitudinal cohort study (EPAD-LCS), which serves as a trial-ready cohort for secondary prevention trials. Amyloid positivity was measured in cerebrospinal fluid as part of the EPAD-LCS assessment. We calculated participation rates and numbers needed to prescreen (NNPS) per participant that was amyloid-positive. We tested if age, sex, education level, APOE status, family history for dementia, memory complaints or memory scores, previously collected in these cohorts, could predict participation and amyloid status.

RESULTS

A total of 2595 participants were contacted for participation in the EPAD-LCS. Participation rates varied by setting between 3 and 59%. The NNPS were 6.9 (clinical cohort), 7.5 (research in-person cohort), 8.4 (research online cohort), and 88.5 (population-based cohort). Participation in the EPAD-LCS (n = 413 (16%)) was associated with lower age (odds ratio (OR) age = 0.97 [0.95-0.99]), high education (OR = 1.64 [1.23-2.17]), male sex (OR = 1.56 [1.19-2.04]), and positive family history of dementia (OR = 1.66 [1.19-2.31]). Among participants in the EPAD-LCS, amyloid positivity (33%) was associated with higher age (OR = 1.06 [1.02-1.10]) and APOE ɛ4 allele carriership (OR = 2.99 [1.81-4.94]). These results were similar across prescreen settings.

CONCLUSIONS

Numbers needed to prescreen varied greatly between settings. Understanding how common AD risk factors link to study participation and amyloid positivity is informative for recruitment strategy of studies on secondary prevention of AD.

The Italian version of Cognitive Function Instrument (CFI) for tracking changes in healthy elderly: results at 1-year follow-up

Cognitive Function Instrument (CFI) is a questionnaire aimed at detecting very early changes in cognitive and functional abilities and useful for monitoring cognitive decline in individuals without clinical impairment. The Italian version has been recently validated. The aim of the present study was to investigate the utility of the Italian version of CFI in tracking early cognitive changes in a cohort of healthy elderly subjects. A consecutive series of 257 cognitively healthy and functionally independent subjects, recruited either among relatives of patients attending our Memory Clinic or as volunteers after advertisement, underwent a baseline neuropsychological assessment. Of them, 157 subjects performed a 1-year follow-up assessment. All subjects completed the CFI, a short questionnaire composed of 14 items administered to both the subject and the referent (study-partner). Cognitive performance was assessed by Mini-Mental State Examination (MMSE) and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). At 1-year follow-up, Cronbach's α was 0.79 (95% CI, 0.74-0.84) in self-report and 0.83 (95% CI, 0.79-0.87) for partner-report. CFI self-report correlated with MMSE (rS = - 0.22, p = 0.006) and RBANS (rS = - 0.23, p = 0.004). CFI partner-report showed negative correlation with MMSE (rS = - 0.17, p = 0.037) and RBANS (rS = - 0.20, p = 0.014). CFI 1-year follow-up score correlated with baseline both in self-report (rS = 0.56, p < 0.001) and partner-report (rS = 0.66, p < 0.001). Baseline CFI partner-report (p = 0.014) and CFI self+partner report (p = 0.023) were associated with RBANS total score less than 85 at 1-year follow-up, while only a trend was found considering baseline CFI self-report. Our results support the suitability of the Italian version of CFI for tracking cognitive changes along aging.

Constructing a Local Potential Participant Registry to Improve Alzheimer's Disease Clinical Research Recruitment

Potential participant registries are tools to address the challenge of slow recruitment to clinical research. In particular, registries may aid recruitment to secondary prevention clinical trials for Alzheimer's disease (AD), which enroll cognitively normal older individuals meeting specific genetic or biomarker criteria. Evidence of registry effectiveness is sparse, as is guidance on optimal designs or methods of conduct. We report our experiences of developing a novel local potential participant registry that implemented online enrollment and data collection. In the first year of operation, 957 individuals submitted email addresses to the registry, of whom 592 self-reported demographic, family history, and medical data. In addition, registrants provided information related to their interest and willingness to be contacted about studies. Local earned media and community education were the most effective methods of recruitment into the registry. Seventy-six (26%) of 298 registrants contacted about studies in the first year enrolled in those studies. One hundred twenty-nine registrants were invited to enroll in a preclinical AD trial, of whom 25 (18%) screened and 6 were randomized. These results indicate that registries can aid recruitment and provide needed guidance for investigators initiating new local registries.

Which MCI Patients Should be Included in Prodromal Alzheimer Disease Clinical Trials?

BACKGROUND

Prodromal Alzheimer disease (AD) clinical trials enroll patients with mild cognitive impairment (MCI) meeting biomarker criteria, but specific enrollment criteria vary among trials.

METHODS

We used data from AD Neuroimaging Initiative (ADNI) MCI participants to assess AD biomarker eligibility, variation in trial outcome measures, and statistical power.

RESULTS

Most (65%) participants meet eligibility criteria based on low cerebrospinal fluid amyloid beta (Aβ). Relative to trials enrolling exclusively based on low cerebrospinal fluid Aβ, trials including participants with a high ratio of phosphorylated tau to Aβ would include an additional 15% of participants. Fewer (34% to 62%) participants met criteria for Aβ and tau. Differences in clinical and demographic characteristics of modeled trial samples were minimal. Those with low Aβ and high tau showed the greatest change over time on outcome measures.

CONCLUSIONS

Eligibility rates for prodromal trials vary depending on the specific biomarker criteria, though differences in demographics and the variation associated with outcome measures are minimal. Broadening inclusion criteria beyond amyloid alone may facilitate recruitment but include patients showing slower progression over time. Biomarker criteria selection should be informed by the goal of enrolling individuals most likely to utilize and benefit from the intervention under investigation in a particular setting.

What matters to people with memory problems, healthy volunteers and health and social care professionals in the context of developing treatment to prevent Alzheimer's dementia? A qualitative study

Background

Alzheimer's disease (AD) is recognized as one of the greatest global public health challenges. There is increasing consensus that optimal disease modification using pharmaceuticals may best be achieved earlier in the disease continuum before symptoms occur. However, more needs to be understood about what outcomes are meaningful to potential participants in clinical trials within this preventative paradigm and how people make trade‐offs between risks and benefits. The Electronic Person‐Specific Outcome Measure (ePSOM) programme is developing an app to capture person‐specific outcomes and preferences in clinical trials.

Objective

As one phase in the ePSOM programme, this study explored what matters when developing new treatments to prevent AD and how trade‐offs are made between risks and benefits, from three perspectives.

Design

Focus groups were conducted with people living with memory problems (n = 21) and healthy volunteers (n = 10), and telephone interviews with health and social care professionals (n = 10). Differences and overlap between the three groups were explored.

Results

Outcomes that matter lie in five key domains in relation to what matters in everyday life: Everyday Functioning; Relationships and Social Connections; Enjoying Life; Sense of Identity; and Alleviating  Symptoms. Insights were gained into the significance of reducing the risk of developing dementia with drugs and the processes of weighing up risks versus benefits.

Discussion and conclusions

The key domains identified are being used to inform the next stage of the ePSOM programme which is to develop a survey to be distributed nationally in the UK to explore these issues further.

Using a birth cohort to study brain health and preclinical dementia: recruitment and participation rates in Insight 46

OBJECTIVE

Identifying and recruiting people with early pre-symptomatic Alzheimer's disease to neuroimaging research studies is increasingly important. The extent to which results of these studies can be generalised depends on the recruitment and representativeness of the participants involved. We now report the recruitment and participation patterns from a neuroscience sub-study of the MRC National Survey of Health and Development, "Insight 46". This study aimed to recruit 500 participants for extensive clinical and neuropsychological testing, and neuroimaging. We investigate how sociodemographic factors, health conditions and health-related behaviours predict participation at different levels of recruitment.

RESULTS

We met our target recruitment (n = 502). Higher educational attainment and non-manual socio-economic position (SEP) were consistent predictors of recruitment. Health-related variables were also predictive at every level of recruitment; in particular higher cognition, not smoking and better self-rating health. Sex and APOE-e4 status were not predictors of participation at any level. Whilst recruitment targets were met, individuals with lower SEP, lower cognition, and more health problems are under-represented in Insight 46. Understanding the factors that influence recruitment are important when interpreting results; for Insight 46 it is likely that health-related outcomes and life course risks will under-estimate those seen in the general population.

Participant outcomes and preferences in Alzheimer's disease clinical trials: The electronic Person-Specific Outcome Measure (ePSOM) development program

INTRODUCTION

Current pharmacological interventions for Alzheimer's dementia delay symptom progression for about a year. Although the outcomes in earlier disease states may include changes in biomarkers, the clinical effectiveness of any intervention can ultimately only be assessed by a patient's self-reported well-being. A better understanding of earlier manifestations of Alzheimer's disease and the drive for relevant outcome measures, allied to technological advances in artificial intelligence, have mediated the electronic Person-Specific Outcome Measure (ePSOM) development program.

METHODS

There are 4 sequential stages in the ePSOM development program-(1) literature review, (2) focus group study, (3) national survey, and (4) development of an app for capturing person-specific outcomes. Here, we report the overall approach to the program incorporating our literature review on patient-reported outcome measures and patient preferences in the Alzheimer's disease population.

RESULTS

Alzheimer's disease trials do not use any patient-reported outcome measures. Quality of life measures are often used as proxies for this, but they do not capture individual needs. Therefore, trials currently fail to reflect the participant's aspirations for effect but rather default to clinicostatistical measure of cognition and function. There is no implementation of patient preferences despite evidence that understanding preferences may influence adherence to treatment.

DISCUSSION

It is important to consider preferences for an intervention and use PROMs for the measure of effectiveness given that both risk and benefit are judged by the recipient of the treatment. The ePSOM development program will deliver the methodology for incorporating meaningful outcomes in clinical trials to expand upon current biological and clinical measurements of effectiveness.