The role of dyadic cognitive report and subjective cognitive decline in early ADRD clinical research and trials: Current knowledge, gaps, and recommendations.

Efficient identification of cognitive decline and Alzheimer's disease (AD) risk in early stages of the AD disease continuum is a critical unmet need. Subjective cognitive decline is increasingly recognized as an early symptomatic stage of AD. Dyadic cognitive report, including subjective cognitive complaints (SCC) from a participant and an informant/study partner who knows the participant well, represents an accurate, reliable, and efficient source of data for assessing risk. However, the separate and combined contributions of self- and study partner report, and the dynamic relationship between the two, remains unclear. The Subjective Cognitive Decline Professional Interest Area within the Alzheimer's Association International Society to Advance Alzheimer's Research and Treatment convened a working group focused on dyadic patterns of subjective report. Group members identified aspects of dyadic-report information important to the AD research field, gaps in knowledge, and recommendations. By reviewing existing data on this topic, we found evidence that dyadic measures are associated with objective measures of cognition and provide unique information in preclinical and prodromal AD about disease stage and progression and AD biomarker status. External factors including dyad (participant-study partner pair) relationship and sociocultural factors contribute to these associations. We recommend greater dyad report use in research settings to identify AD risk. Priority areas for future research include (1) elucidation of the contributions of demographic and sociocultural factors, dyad type, and dyad relationship to dyad report; (2) exploration of agreement and discordance between self- and study partner report across the AD syndromic and disease continuum; (3) identification of domains (e.g., memory, executive function, neuropsychiatric) that predict AD risk outcomes and differentiate cognitive impairment due to AD from other impairment; (4) development of best practices for study partner engagement; (5) exploration of study partner report as AD clinical trial endpoints; (6) continued development, validation, and optimization, of study partner report instruments tailored to the goals of the research and population.

Exploring Cognitively Loaded Physical Activity Compared With Control to Improve Global Cognitive Function in Older Community-Dwelling Adults With Mild Cognitive Impairment: Systematic Review With Meta-Analysis.

OBJECTIVE: A systematic review with a meta-analysis explored effects of cognitively loaded physical activity interventions on global cognition in community-dwelling older adults (≥65 years of age) experiencing mild cognitive impairment (MCI), compared to any control. METHODS: A literature search was conducted in 4 databases (MEDLINE [OvidSP], PubMed, CINAHL, and the Cochrane Central Register of Controlled Trials [Wiley]) from inception until January 30, 2018. The meta-analysis was conducted with Review Manager 5.3. RESULTS: Six randomized controlled trials (RCTs) with 547 participants were identified. The interventions ranged from 4 to 52 weeks. Baseline and initial follow-up assessments were used. The primary pooled analysis of all RCTs demonstrated a nonsignificant trivial effect (standardized mean difference [SMD] 0.07, 95% confidence interval [CI] -0.44 to 0.58) favoring the intervention. In pooled subanalysis of 4 RCTs (n = 405) using the same global cognition measure (Mini-Mental State Examination) and duration of intervention >12 weeks, the intervention group achieved a small but significant improvement for global cognition (SMD 0.45, 95% CI 0.14 to 0.75). CONCLUSION: When all the RCTs were pooled, the effect of cognitively loaded physical activity intervention on global cognitive function in older adults with MCI remained unclear. The subgroup analysis provides translation evidence for future RCT study designs.

Rethinking researcher bias in health research.

Bias is an ambiguous term, defined in different ways. In conventional usage, it indicates unwarranted prejudice. However, in health research, the notion that bias is invariably bad is biased. Although research bias is an error that is always harmful, researcher bias is a tendency to think in a particular way that may obscure or illuminate attempts to address research questions. Researcher bias begins with pre-judgements whose continuing evaluation infuses the subjectivity of researchers as persons who are socially situated in health sciences focusing on human subjects. Two sets of conditions can make this bias in health researchers useful. The first is volume control. Researchers can vary the loudness of their own and other voices in different research environments. The second condition is smart working. It balances researcher bias against analytic thinking to work creatively with irregularity and uncertainty. Thus, health researchers need to bring their biases to consciousness. A dialectical approach can then engage the biases as conversational partners to innovate health policy that is informed by principles including transparency, good faith and tolerance. Less critical than whether researchers are biased is whose interests their bias serves given their positionality and role.

Modifiable Risk Factors and Change in Cognition of Maori and Non-Maori in Advanced Age: LiLACS NZ.

OBJECTIVE: This study investigated whether previously identified modifiable risk factors for dementia were associated with cognitive change in Maori (indigenous people of New Zealand) and non-Maori octogenarians of LiLACS NZ (Life and Living in Advanced Age; a Cohort Study in New Zealand), a longitudinal study. METHOD: Multivariable repeated-measure mixed effect regression models were used to assess the association between modifiable risk factors and sociodemographic variables at baseline, and cognitive change over 6 years, with p values of <.05 regarded as statistically significant. RESULTS: Modifiable factors associated with cognitive change differed between ethnic groups. Depression was a negative factor in Maori only, secondary education in non-Maori was protective, and obesity predicted better cognition over time for Maori. Diabetes was associated with decreased cognition for both Maori and non-Maori. CONCLUSION: Our results begin to address gaps in the literature and increase understanding of disparities in dementia risk by ethnicity. These findings have implications for evaluating the type and application of culturally appropriate methods to improve cognition.

Identifying risk profiles for excess sedentary behaviour in youth using individual, family and neighbourhood characteristics.

There are few known determinants of sedentary behaviour (SB) in children. We generated and compared profiles associated with risk of excess SB among children (n = 294) both at 8-10 and 10-12 years of age (Visits 1 and 2, respectively), using data from the QUebec Adipose and Lifestyle InvesTigation in Youth. Excess SB was measured by accelerometry and defined as >50% of total wear time at <100 counts/minutes. Recursive partitioning analyses were performed with candidate individual-, family-, and neighbourhood-level factors assessed at Visit 1, and distinct groups at varying risk of excess SB were identified for both timepoints. From the ages of 8-10 to 10-12 years, the prevalence of excess SB more than doubled (24.5% to 57.1%). At Visit 1, excess SB was greatest (73%) among children simultaneously not meeting physical activity guidelines, reporting >2 h/day of weekday non-academic screen time, living in low-dwelling density neighbourhoods, having poor park access, and living in neighbourhoods with greater disadvantage. At Visit 2, the high-risk group (70%) was described by children simultaneously not meeting physical activity guidelines, reporting >2 h/day of non-academic screen time on weekends, and living in neighbourhoods with low disadvantage. Risk factors related to individual lifestyle behaviours are generally consistent, and neighbourhood factors generally inconsistent, as children age from late childhood to pre-adolescence. Multiple factors from developmental, behavioural and contextual domains increase risk for excess sedentary behaviour; these warrant consideration to devise effective prevention or management strategies.

Fostering global primary care research: a capacity-building approach.

The Alma Ata and Astana Declarations reaffirm the importance of high-quality primary healthcare (PHC), yet the capacity to undertake PHC research-a core element of high-quality PHC-in low-income and middle-income countries (LMIC) is limited. Our aim is to explore the current risks or barriers to primary care research capacity building, identify the ongoing tensions that need to be resolved and offer some solutions, focusing on emerging contexts. This paper arose from a workshop held at the 2019 North American Primary Care Research Group Annual Meeting addressing research capacity building in LMICs. Five case studies (three from Africa, one from South-East Asia and one from South America) illustrate tensions and solutions to strengthening PHC research around the world. Research must be conducted in local contexts and be responsive to the needs of patients, populations and practitioners in the community. The case studies exemplify that research capacity can be strengthened at the micro (practice), meso (institutional) and macro (national policy and international collaboration) levels. Clinicians may lack coverage to enable research time; however, practice-based research is precisely the most relevant for PHC. Increasing research capacity requires local skills, training, investment in infrastructure, and support of local academics and PHC service providers to select, host and manage locally needed research, as well as to disseminate findings to impact local practice and policy. Reliance on funding from high-income countries may limit projects of higher priority in LMIC, and 'brain drain' may reduce available research support; however, we provide recommendations on how to deal with these tensions.

Diagnostic accuracy of a global cognitive screen for Maori and non-Maori octogenarians.

INTRODUCTION: We assessed the sensitivity and specificity of the Modified Mini-Mental State Examination (3MS) in predicting dementia and cognitive impairment in Maori (indigenous people of New Zealand) and non-Maori octogenarians. METHODS: A subsample of participants from Life and Living in Advanced Age: a Cohort Study in New Zealand were recruited to determine the 3MS diagnostic accuracy compared with the reference standard. RESULTS: Seventy-three participants (44% Maori) completed the 3MS and reference standard assessments. The 3MS demonstrated strong diagnostic accuracy to detect dementia with areas under the curve of 0.87 for Maori and 0.9 for non-Maori. Our cutoffs displayed ethnic variability and are approximately 5 points greater than those commonly applied. Cognitive impairment yielded low accuracy, and discriminatory power was not established. DISCUSSION: Cutoffs that are not age or ethnically appropriate may compromise the accuracy of cognitive screens. Consequently, older age and indigeneity increase the risk of mislabeled cognitive status.