Future Directions for Dementia Risk Reduction and Prevention Research: An International Research Network on Dementia Prevention Consensus

Longitudinal Patterns of Systolic Blood Pressure, Diastolic Blood Pressure, Cardiorespiratory Fitness, and Their Association With Dementia Risk: The HUNT Study

BACKGROUND

High blood pressure and poor cardiorespiratory fitness are independent risk factors for dementia. However, few studies have examined if combined longitudinal patterns of these modifiable risk factors are associated with dementia risk.

METHODS

In this prospective cohort study, we used data from the population-based Trøndelag Health (HUNT) Study, Norway. We applied group-based multidimensional trajectory modeling to identify age-specific multidimensional trajectories of SBP, DBP, and estimated cardiorespiratory fitness across 3 surveys (HUNT1, 1984-1986 to HUNT3, 2006-2008). Dementia was diagnosed in the HUNT4 70+ substudy in 2017-2019. We used multivariate logistic regression to estimate odds ratios (ORs) and risk differences (RDs) of dementia.

RESULTS

In total, 7 594 participants (54.9% women) were included, with a mean age of 44.7 (SD 6.3) years at HUNT1. Dementia was diagnosed in 1 062 (14.0%) participants. We identified 2 multidimensional trajectories throughout adulthood within 3 age groups: one with higher systolic blood pressure (SBP) and diastolic blood pressure (DBP), and lower estimated cardiorespiratory fitness (the poorer group), and one with lower SBP and DBP, and higher cardiorespiratory fitness (the better group). After adjustment for sex, apolipoprotein E ε4 status, education, marital status, and diabetes, the better group had consistently lower risk of dementia in all age groups with the lowest OR in the middle-aged group of 0.63 (95% confidence intervals [95% CI]: 0.51, 0.78) with corresponding RD of -0.07 (95% CI: -0.10, -0.04).

CONCLUSIONS

Having a beneficial multidimensional trajectory of SBP, DBP, and cardiorespiratory fitness in adulthood was associated with reduced dementia risk. Aiming for optimal SBP, DBP, and estimated cardiorespiratory fitness throughout adulthood may reduce dementia risk.

Late Life Cognitive Function Trajectory Among the Chinese Oldest-Old Population-A Machine Learning Approach

Informed by the biopsychosocial framework, our study uses the Chinese Longitudinal Healthy Longevity Survey (CLHLS) dataset to examine cognitive function trajectories among the oldest-old (80+). Employing K-means clustering, we identified two latent groups: High Stability (HS) and Low Stability (LS). The HS group maintained satisfactory cognitive function, while the LS group exhibited consistently low function. Lasso regression revealed predictive factors, including socioeconomic status, biological conditions, mental health, lifestyle, psychological, and behavioral factors. This data-driven approach sheds light on cognitive aging patterns and informs policies for healthy aging. Our study pioneers non-parametric machine learning methods in this context.

Umbrella review and Delphi study on modifiable factors for dementia risk reduction

A 2013 systematic review and Delphi consensus study identified 12 modifiable risk and protective factors for dementia, which were subsequently merged into the "LIfestyle for BRAin health" (LIBRA) score. We systematically evaluated whether LIBRA requires revision based on new evidence. To identify modifiable risk and protective factors suitable for dementia risk reduction, we combined an umbrella review of systematic reviews and meta-analyses with a two-round Delphi consensus study. The review of 608 unique primary studies and opinions of 18 experts prioritized six modifiable factors: hearing impairment, social contact, sleep, life course inequalities, atrial fibrillation, and psychological stress. Based on expert ranking, hearing impairment, social contact, and sleep were considered the most suitable candidates for inclusion in updated dementia risk scores. As such, the current study shows that dementia risk scores need systematic updates based on emerging evidence. Future studies will validate the updated LIBRA score in different cohorts. HIGHLIGHTS: An umbrella review was combined with opinions of 18 dementia experts. Various candidate targets for dementia risk reduction were identified. Experts prioritized hearing impairment, social contact, and sleep. Re-assessment of dementia risk scores is encouraged. Future work should evaluate the predictive validity of updated risk scores.

Effects of Health Responsibility Frames on Attributions, Emotions, and Social Support Intentions in the Context of Dementias

When news stories cover health and diseases, they often address issues of responsibility. These responsibility frames can affect recipients' responsibility beliefs (i.e., attributions) and thereby affect emotions and motivations to support people affected by health problems. To date, it is not fully understood how responsibility frames affect these attributions, emotions, and social support intentions in the context of dementia. In an online experiment with N = 1,059 German participants, we tested the effects of different responsibility frames (individual vs. contextual) on social support intentions through responsibility attributions and emotional reactions in the context of dementia. Results show that responsibility frames affect responsibility attributions and social support intentions. Mediation analysis shows that the effect of contextual responsibility frames on social support intention is partially mediated by responsibility attribution and emotions (sympathy and anger). We discuss these findings considering framing effects research and media coverage.

Association between metabolic syndrome and risk of incident dementia in UK Biobank

INTRODUCTION

The association between metabolic syndrome (MetS) and incident dementia remains inconclusive.

METHODS

In 176,249 dementia-free UK Biobank participants aged ≥60 years at baseline, Cox proportional-hazards models were used to investigate the association between MetS and incident dementia. MetS was defined as the presence of ≥3 of the following: elevated waist circumference, triglycerides, blood pressure, blood glucose, and reduced high-density lipoprotein cholesterol.

RESULTS

Over 15 years of follow-up (median = 12.3), 5255 participants developed dementia. MetS was associated with an increased risk of incident dementia (hazard ratio [HR]: 1.12, 95% confidence interval [CI]: 1.06, 1.18). The association remained consistent when restricting to longer follow-up intervals: >5 to 10 years (HR: 1.17, 95% CI: 1.07, 1.27) and >10 years (HR: 1.22, 95% CI: 1.12, 1.32). Stronger associations were observed in those with ≥4 MetS components and in apolipoprotein-E (APOE)-ε4 non-carriers.

DISCUSSION

In this large population-based prospective cohort, MetS was associated with an increased risk of dementia.

HIGHLIGHTS

MetS was associated with a 12% increased risk of incident all-cause dementia. Associations remained similar after restricting the analysis to those with longer follow-up. The presence of four or five MetS components was significantly associated with dementia. Stronger associations were observed in those with a low genetic risk for dementia.

Life-Course Brain Health as a Determinant of Late-Life Mental Health: American Association for Geriatric Psychiatry Expert Panel Recommendations

This position statement of the Expert Panel on Brain Health of the American Association for Geriatric Psychiatry (AAGP) emphasizes the critical role of life course brain health in shaping mental well-being during the later stages of life. Evidence posits that maintaining optimal brain health earlier in life is crucial for preventing and managing brain aging-related disorders such as dementia/cognitive decline, depression, stroke, and anxiety. We advocate for a holistic approach that integrates medical, psychological, and social frameworks with culturally tailored interventions across the lifespan to promote brain health and overall mental well-being in aging adults across all communities. Furthermore, our statement underscores the significance of prevention, early detection, and intervention in identifying cognitive decline, mood changes, and related mental illness. Action should also be taken to understand and address the needs of communities that traditionally have unequal access to preventive health information and services. By implementing culturally relevant and tailored evidence-based practices and advancing research in geriatric psychiatry, behavioral neurology, and geroscience, we can enhance the quality of life for older adults facing the unique challenges of aging. This position statement emphasizes the intrinsic link between brain health and mental health in aging, urging healthcare professionals, policymakers, and a broader society to prioritize comprehensive strategies that safeguard and promote brain health from birth through later years across all communities. The AAGP Expert Panel has the goal of launching further activities in the coming months and years.

Change in physical activity and systolic blood pressure trajectories throughout mid-life and the development of dementia in older age: the HUNT study

BACKGROUND

There is lack of research on combinations of possible modifiable risk factors for dementia in a life-time perspective. Dementia has currently no cure, and therefore new knowledge of preventive factors is important. The purpose of this study is to investigate if changes in physical activity (PA) in combinations with systolic blood pressure (SBP) trajectories in mid to late life are related to development of dementia in older age.

METHODS

This prospective cohort study uses data from four consecutive surveys of the HUNT Study, Norway. Dementia was assessed in the HUNT4 70 + sub-study (2017-19). Group-based trajectory modelling identified three SBP trajectories from HUNT1 (1984-86) to HUNT3 (2006-2008): low, middle, and high. Change in PA was categorized into four groups based on high or low PA level at HUNT1 and HUNT3 and were combined with the SBP trajectories resulting in 12 distinct categories. Logistic regression was used to estimate odds ratios (ORs) of dementia.

RESULTS

A total of 8487 participants (55% women, mean age (SD) 44.8 (6.5) years at HUNT1) were included. At HUNT4 70 + , 15.2% had dementia. We observed an overall decrease in OR of dementia across the PA/SBP categories when ranked from low to high PA (OR, 0.96; 95% CI, 0.93 to 1.00, P = 0.04). Within PA groups, a low SBP trajectory was associated with lower OR for dementia, apart from those with decreasing PA. The strongest association was observed for people with stable high PA and low SBP trajectory (OR, 0.38; 95% confidence interval (CI), 0.13 to 1.10 and adjusted risk difference, -8.34 percentage points; 95% CI, -15.32 to -1.36).

CONCLUSION

Our findings illustrate the clinical importance of PA and SBP for dementia prevention and that favorable levels of both are associated with reduced occurrence of dementia.

Young Adult Brain Capital: A New Opportunity for Dementia Prevention

The potential for future prevention of Alzheimer's disease and related dementias (ADRD) through healthy lifestyle change is spurring a positive brain health movement. However, most ADRD research continues to focus on mid- and later life. We lack evidence regarding risk exposure and protective factors in young adulthood, i.e., 18-39 years. Brain capital is an emerging framework that represents the combination of education, knowledge, skills, and optimal brain health that people accumulate over their lives. Building on this framework, we present a new model that focuses on optimizing brain health in young adulthood; namely, young adult brain capital. Increasing focus on younger populations is critical for developing citizens who are emotionally intelligent, resilient and can anticipate and cope with rapid changes in the world. By understanding the values that are key drivers and motivators for young adults, we can empower the next generation to become active agents in optimizing their brain health and reducing their risk for future ADRD.

Dementia prevention in memory clinics: recommendations from the European task force for brain health services

Observational population studies indicate that prevention of dementia and cognitive decline is being accomplished, possibly as an unintended result of better vascular prevention and healthier lifestyles. Population aging in the coming decades requires deliberate efforts to further decrease its prevalence and societal burden. Increasing evidence supports the efficacy of preventive interventions on persons with intact cognition and high dementia risk. We report recommendations for the deployment of second-generation memory clinics (Brain Health Services) whose mission is evidence-based and ethical dementia prevention in at-risk individuals. The cornerstone interventions consist of (i) assessment of genetic and potentially modifiable risk factors including brain pathology, and risk stratification, (ii) risk communication with ad-hoc protocols, (iii) risk reduction with multi-domain interventions, and (iv) cognitive enhancement with cognitive and physical training. A roadmap is proposed for concept validation and ensuing clinical deployment.

Alzheimer’s Disease and Inflammaging

Alzheimer’s disease is one of the most common age-related neurodegenerative disorders. The main theory of Alzheimer’s disease progress is the amyloid-β cascade hypothesis. However, the initial mechanisms of insoluble forms of amyloid-β formation and hyperphosphorylated tau protein in neurons remain unclear. One of the factors, which might play a key role in senile plaques and tau fibrils generation due to Alzheimer’s disease, is inflammaging, i.e., systemic chronic low-grade age-related inflammation. The activation of the proinflammatory cell phenotype is observed during aging, which might be one of the pivotal mechanisms for the development of chronic inflammatory diseases, e.g., atherosclerosis, metabolic syndrome, type 2 diabetes mellitus, and Alzheimer’s disease. This review discusses the role of the inflammatory processes in developing neurodegeneration, activated during physiological aging and due to various diseases such as atherosclerosis, obesity, type 2 diabetes mellitus, and depressive disorders.

The adverse effect of modifiable dementia risk factors on cognition amplifies across the adult lifespan

Background

Reversible lifestyle behaviors (modifiable risk factors) can reduce dementia risk by 40%, but their prevalence and association with cognition throughout the adult lifespan is less well understood.

Methods

The associations between the number of modifiable risk factors for dementia (low education, hypertension, hearing loss, traumatic brain injury, alcohol or substance abuse, diabetes, smoking, and depression) and cognition were examined in an online sample (N = 22,117, ages 18-89).

Findings

Older adults (ages 66-89) had more risk factors than middle-aged (ages 45-65) and younger adults (ages 18-44). Polynomial regression revealed that each additional risk factor was associated with lower cognitive performance (equivalent to 3 years of aging), with a larger association as age increased. People with no risk factors in their forties to seventies showed similar cognitive performance to people 10 or 20 years younger with many risk factors.

Interpretation

Modifiable dementia risk factors amplify lifespan age differences in cognitive performance.

Facets of Personality and Risk of Cognitive Impairment: Longitudinal Findings in a Rural Community from Sardinia

Background: Few studies have examined the associations between personality facets and dementia risk and rarely included individuals from rural settings or with low education. Objective: To examine the association between personality and the risk of cognitive impairment. Methods: Participants (N = 1,668; age 50 to 94 at baseline; 56.4% women; 86.5% less than high school diploma) were from a rural region of Sardinia (Italy) who completed the Revised NEO Personality Inventory (NEO-PI-R) during the first wave (2001–2004) and the Mini-Mental State Examination (MMSE) at waves two to five (2005–2021). Cox regression was used to test personality and covariates as predictors of cognitive impairment based on MMSE education-adjusted cutoffs. Results: During the up to 18-year follow-up (M = 10.38; SD = 4.76), 187 individuals (11.2%) scored as cognitively impaired. Participants with higher neuroticism (particularly the depression facet [HR = 1.22, 95% CI = 1.06–1.40]), and lower agreeableness (particularly the modesty facet [HR = 0.83, 95% CI = 0.71–0.97]) and lower conscientiousness (particularly the dutifulness facet [HR = 0.78, 95% CI = 0.67–0.92]) were at higher risk of cognitive impairment. Lower warmth ([HR = 0.75, 95% CI = 0.65–0.87], facet of extraversion) and ideas ([HR = 0.76, 95% CI = 0.65–0.89], facet of openness) were also associated with increased risk of impairment. These associations were virtually unchanged in models that accounted for other risk factors, including smoking, depression, obesity, hypertension, diabetes, and apolipoprotein E (APOE) ɛ4 carrier status. Across the five domains, sex and the APOE variant did not moderate the associations. Conclusion: In a sample with demographic characteristics underrepresented in dementia research, this study identifies personality domains and facets most relevant to the risk of cognitive impairment.

Multidomain interventions for risk reduction and prevention of cognitive decline and dementia: current developments

PURPOSE OF REVIEW

The potential for dementia prevention is deemed substantial if modifiable risk factors were addressed. First large-scale multidomain lifestyle interventions aiming at reducing risk of cognitive decline and dementia have yielded mixed but promising evidence.

RECENT FINDINGS

Despite the impact of the COVID-19 pandemic on trials conduction, causing interruptions and delays, the research landscape on multidomain interventions is growing rapidly. The successful Finish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) has led to an adaptation of the FINGER model in trials underway or being planned in over 40 countries. Recent studies identified barriers and facilitators of and adherence to multidomain interventions, showed the suitability of dementia risk scores as surrogate outcomes, and suggested mechanisms. Multidomain interventions are increasingly conducted in the Global South, and study protocols are increasingly testing expanded FINGER models, for example, with pharmacological components, in digital/remote settings and co-designed personalized interventions.

SUMMARY

Though results remain mixed, the many ongoing trials will provide more conclusive evidence within the next few years and help to optimize interventions. Continued international collaboration is pivotal to scale and accelerate the development and implementation of effective multidomain interventions as part of larger public health strategies to counteract the global dementia increase.

Educating the masses to address a global public health priority: The Preventing Dementia Massive Open Online Course (MOOC)

Dementia is a global public health priority and risk reduction is an important pillar of the public health response. While 40% of cases are estimated to be attributable to modifiable health and lifestyle risk factors, public awareness of the evidence is low, limiting peoples’ opportunity to adopt risk-reducing behaviours. To address this gap, we designed, implemented, and evaluated an educational intervention, the Preventing Dementia Massive Open Online Course (PDMOOC). This mixed-methods study examined the reach and impact of the free and globally available PDMOOC, to assess its potential to provide effective dementia risk reduction education to a broad international audience. Over 100,000 individuals participated in the PDMOOC across seven iterations from 2016 to 2020, with 55,739 of these consenting to participate in research. Their mean age was 49 years (SD = 15), they came from 167 different countries, and the majority were female (86%), had completed post-secondary education (77%), lived in high-income countries (93%) and worked in health care and social assistance (63%). This demographic profile changed across time, with more men, people with higher education and people from low- and middle-income countries participating in recent course iterations. Two-thirds of participants completed the PDMOOC; completion was associated with being aged 50 to 70 years, residing in a high-income country, having tertiary education, and working in the health sector. Participants reported high levels of satisfaction with the PDMOOC, improved dementia risk reduction understanding and self-efficacy, increased motivation to maintain healthy lifestyles, and, importantly, application of their learning to health behaviour change with the potential to reduce their dementia risk. The PDMOOC educated a large global audience about dementia risk reduction, which contributed to participants making risk-reducing behaviour changes. This suggests MOOCs can be a successful public health strategy to improve dementia risk reduction understanding.

Island Study Linking Aging and Neurodegenerative Disease (ISLAND) Targeting Dementia Risk Reduction: Protocol for a Prospective Web-Based Cohort Study

BACKGROUND

Up to 40% of incident dementia is considered attributable to behavioral and lifestyle factors. Given the current lack of medical treatments and the projected increase in dementia prevalence, a focus on prevention through risk reduction is needed.

OBJECTIVE

We aim to increase dementia risk knowledge and promote changes in dementia risk behaviors at individual and population levels.

METHODS

The Island Study Linking Aging and Neurodegenerative Disease (ISLAND) is a long-term prospective, web-based cohort study with nested interventions that will be conducted over a 10-year period. Target participants (n=10,000) reside in Tasmania and are aged 50 years or over. Survey data on knowledge, attitudes, and behaviors related to modifiable dementia risk factors will be collected annually. After each survey wave, participants will be provided with a personalized dementia risk profile containing guidelines for reducing risk across 9 behavioral and lifestyle domains and with opportunities to engage in educational and behavioral interventions targeting risk reduction. Survey data will be modeled longitudinally with intervention engagement indices, cognitive function indices, and blood-based biomarkers, to measure change in risk over time.

RESULTS

In the initial 12 months (October 2019 to October 2020), 6410 participants have provided baseline data. The study is ongoing.

CONCLUSIONS

Recruitment targets are feasible and efforts are ongoing to achieve a representative sample. Findings will inform future public health dementia risk reduction initiatives by showing whether, when, and how dementia risk can be lowered through educational and behavioral interventions, delivered in an uncontrolled real-world context.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/34688.

Subjective memory concerns, poor vascular health, and male sex predict exacerbated memory decline trajectories: An integrative data-driven class and prediction analysis

OBJECTIVE

Subjective memory decline (SMD) has been identified as a potential early marker of nonnormal and accelerated cognitive decline. We performed data-driven analyses that integrated trajectory classification with prediction modeling to test declining trajectory class prediction by SMD facets, pulse pressure (PP; i.e., a robust proxy for vascular health), and sex.

METHOD

The longitudinal design featured memory trajectories across a 40-year band (55-95 years) of nondemented aging (N = 580; Mage = 70.2 years; 65% female) from the Victoria Longitudinal Study. First, latent class growth analyses identified distinct classes of memory trajectories. Second, we used the three-step method (R3STEP) to predict membership in the declining memory classes using six measures: memory complaints, memory concerns, memory compensation, memory self-efficacy, PP, and sex.

RESULTS

First, we identified four classes of memory aging trajectories: (a) stable memory aging (STABLE), (b) typical memory aging (TYPICAL), (c) slowly declining memory aging (SLOW), and (d) rapidly declining memory aging (RAPID). Second, more memory concerns predicted membership in the SLOW and RAPID classes. Higher PP predicted membership in the SLOW class. Male sex predicted membership in the declining (TYPICAL, SLOW, RAPID) classes.

CONCLUSION

Among SMD facets, memory concerns represent the most severe degree of apprehension about subjectively experienced memory losses. The present integrative data-driven analysis indicated that such concerns predicted membership in declining memory trajectory classes in addition to worse vascular health (higher PP) and sex (male). In nondemented aging, concerns about increasing memory failures may be veridical indicators of memory loss, especially when coupled with vascular comorbidity and being male. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Differential Cognitive Decline in Alzheimer's Disease Is Predicted by Changes in Ventricular Size but Moderated by Apolipoprotein E and Pulse Pressure

BACKGROUND

Differential cognitive trajectories in Alzheimer's disease (AD) may be predicted by biomarkers from multiple domains.

OBJECTIVE

In a longitudinal sample of AD and AD-related dementias patients (n = 312), we tested whether 1) change in brain morphometry (ventricular enlargement) predicts differential cognitive trajectories, 2) further risk is contributed by genetic (Apolipoprotein E [APOE] ɛ4+) and vascular (pulse pressure [PP]) factors separately, and 3) the genetic + vascular risk moderates this pattern.

METHODS

We applied a dynamic computational approach (parallel process models) to test both concurrent and change-related associations between predictor (ventricular size) and cognition (executive function [EF]/attention). We then tested these associations as stratified by APOE (ɛ4-/ɛ4+), PP (low/high), and APOE+ PP (low/intermediate/high) risk.

RESULTS

First, concurrently, higher ventricular size predicted lower EF/attention performance and, longitudinally, increasing ventricular size predicted steeper EF/attention decline. Second, concurrently, higher ventricular size predicted lower EF/attention performance selectively in APOEɛ4+ carriers, and longitudinally, increasing ventricular size predicted steeper EF/attention decline selectively in the low PP group. Third, ventricular size and EF/attention associations were absent in the high APOE+ PP risk group both concurrently and longitudinally.

CONCLUSION

As AD progresses, a threshold effect may be present in which ventricular enlargement in the context of exacerbated APOE+ PP risk does not produce further cognitive decline.

Effects of Aerobic, Resistance, or Combined Exercise Training Among Older Adults with Subjective Memory Complaints: A Randomized Controlled Trial

BACKGROUND

Physical exercise is suggested to be effective for preventing cognitive decline in older adults, but the relative efficacy of different types of exercise have yet to be clarified.

OBJECTIVE

This single-blinded randomized controlled trial was designed to investigate the differential effects of aerobic exercise training (AT), resistance exercise training (RT), and combined exercise training (CT) on cognition in older adults with subjective memory complaints (SMC).

METHODS

Community-dwelling older adults with SMC (n = 415; mean age = 72.3 years old) were randomly assigned to one of the four groups: AT, RT, CT, or control group. The study consisted of two phases: a 26-week intervention and a 26-week follow-up. The participants were evaluated at baseline, 26 weeks (postintervention), and 52 weeks (follow-up). The primary outcome of this study was memory function, which was assessed using the Logical Memory II subtest of the Wechsler Memory Scale-Revised (WMS-R) score. The secondary outcomes included global cognitive function, verbal fluency, working memory, processing speed, and executive functions.

RESULTS

Intention-to-treat analysis by a mixed-effect model repeated measure showed that the AT group had significantly improved performance on the WMS-R Logical Memory II test (2.74 [1.82-3.66] points) than the control group (1.36 [0.44-2.28] points) at the postintervention assessment (p = 0.037). The effect was more pronounced in those without amnesia than those with amnesia. No significant improvement was observed in the RT and CT groups.

CONCLUSION

This study suggests that AT intervention can improve delayed memory in community-dwelling older adults, particularly in individuals without objective memory decline.