Integrating a multimodal lifestyle intervention with medical food in prodromal Alzheimer's disease: the MIND-ADmini randomized controlled trial.

BACKGROUND: The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) showed cognitive benefits from a multidomain lifestyle intervention in at-risk older people. The LipiDiDiet trial highlighted benefits of medical food in prodromal Alzheimer's disease (AD). However, the feasibility and impact of multimodal interventions combining lifestyle with medical food in prodromal AD is unclear. METHODS: MIND-ADmini was a 6-month multinational (Sweden, Finland, Germany, France) proof-of-concept randomized controlled trial (RCT). Participants were 60-85 years old, had prodromal AD (International Working Group-1 criteria), and vascular/lifestyle risk factors. The parallel-group RCT had three arms: multimodal lifestyle intervention (nutritional guidance, exercise, cognitive training, vascular/metabolic risk management and social stimulation); multimodal lifestyle intervention + medical food (Fortasyn Connect); and regular health advice/care (control). Participants were randomized 1:1:1 (computer-generated allocation at each site). Outcome evaluators were blinded to randomization. Primary outcome was feasibility of the multimodal intervention, evaluated by recruitment rate during a 6-month recruitment phase, overall adherence in each intervention arm, and 6-month retention rate. Successful adherence was pre-specified as attending ≥ 40% of sessions/domain in ≥ 2/4 domains (lifestyle intervention), and consuming ≥ 60% of the medical food (lifestyle intervention + medical food). The secondary outcomes included adherence/participation to each intervention component and overall adherence to healthy lifestyle changes, measured using a composite score for healthy lifestyle. Cognitive assessments were included as exploratory outcomes, e.g. Clinical Dementia Rating scale. RESULTS: During September 2017-May 2019, 93 individuals were randomized (32 lifestyle intervention, 31 lifestyle + medical food, and 30 control group). Overall recruitment rate was 76.2% (64.8% during the first 6 months). Overall 6-month retention rate was 91.4% (lifestyle intervention 87.5%; lifestyle + medical food 90.3%; control 96.7%). Domain-specific adherence in the lifestyle intervention group was 71.9% to cognitive training, 78.1% exercise, 68.8% nutritional guidance, and 81.3% vascular risk management; and in the lifestyle + medical food group, 90.3% to cognitive training, 87.1% exercise, 80.7% nutritional guidance, 87.1% vascular risk management, and 87.1% medical food. Compared with control, both intervention arms showed healthy diet improvements (ßLifestyle×Time = 1.11, P = 0.038; ßLifestyle+medical food×Time = 1.43, P = 0.007); the lifestyle + medical food group also showed vascular risk reduction (P = 0.043) and less cognitive-functional decline (P < 0.05, exploratory analysis). There were 5 serious adverse events (control group: 1; lifestyle intervention: 3; lifestyle + medical food: 1) unrelated to interventions. CONCLUSIONS: The multidomain lifestyle intervention, alone or combined with medical food, had good feasibility and adherence in prodromal AD. Longer-term cognitive and other health benefits should be further investigated in a larger-scale trial. TRIAL REGISTRATION: ClinicalTrials.gov NCT03249688.

Prevention of dementia using mobile phone applications (PRODEMOS): a multinational, randomised, controlled effectiveness-implementation trial.

BACKGROUND: The expected increase of dementia prevalence in the coming decades will mainly be in low-income and middle-income countries and in people with low socioeconomic status in high-income countries. This study aims to reduce dementia risk factors in underserved populations at high-risk using a coach-supported mobile health (mHealth) intervention. METHODS: This open-label, blinded endpoint, hybrid effectiveness-implementation randomised controlled trial (RCT) investigated whether a coach-supported mHealth intervention can reduce dementia risk in people aged 55-75 years of low socioeconomic status in the UK or from the general population in China with at least two dementia risk factors. The primary effectiveness outcome was change in cardiovascular risk factors, ageing, and incidence of dementia (CAIDE) risk score from baseline to after 12-18 months of intervention. Implementation outcomes were coverage, adoption, sustainability, appropriateness, acceptability, fidelity, feasibility, and costs assessed using a mixed-methods approach. All participants with complete data on the primary outcome, without imputation of missing outcomes were included in the analysis (intention-to-treat principle). This trial is registered with ISRCTN, ISRCTN15986016, and is completed. FINDINGS: Between Jan 15, 2021, and April 18, 2023, 1488 people (601 male and 887 female) were randomly assigned (734 to intervention and 754 to control), with 1229 (83%) of 1488 available for analysis of the primary effectiveness outcome. After a mean follow-up of 16 months (SD 2·5), the mean CAIDE score improved 0·16 points in the intervention group versus 0·01 in the control group (mean difference -0·16, 95% CI -0·29 to -0·03). 1533 (10%) invited individuals responded; of the intervention participants, 593 (81%) of 734 adopted the intervention and 367 (50%) of 734 continued active participation throughout the study. Perceived appropriateness (85%), acceptability (81%), and fidelity (79%) were good, with fair overall feasibility (53% of intervention participants and 58% of coaches), at low cost. No differences in adverse events between study arms were found. INTERPRETATION: A coach-supported mHealth intervention is modestly effective in reducing dementia risk factors in those with low socioeconomic status in the UK and any socioeconomic status in China. Implementation is challenging in these populations, but those reached actively participated. Whether this intervention will result in less cognitive decline and dementia requires a larger RCT with long follow-up. FUNDING: EU Horizon 2020 Research and Innovation Programme and the National Key R&D Programmes of China. TRANSLATION: For the Mandarin translation of the abstract see Supplementary Materials section.

Plasma p-tau181 as an outcome and predictor of multidomain intervention effects: a secondary analysis of a randomised, controlled, dementia prevention trial.

BACKGROUND: It is unknown whether multidomain interventions, which might preserve late-life cognition, affect Alzheimer's disease pathology. Previous studies measured cerebrospinal fluid and imaging Alzheimer's disease biomarkers in small subsamples of multidomain trial participants. Newly developed assays enable the measurement of blood-based Alzheimer's disease biomarkers in larger samples. We aimed to assess whether plasma tau phosphorylated at threonine 181 (p-tau181) was able to detect or predict 3-year multidomain intervention effects. METHODS: This is a secondary analysis of the randomised, controlled, Multidomain Alzheimer Prevention Trial (MAPT) testing a 3-year multidomain intervention, omega-3 fatty acid supplementation, or both versus placebo, in individuals aged 70 years and older in 13 memory centres in France and Monaco. Plasma p-tau181 was measured in stored blood samples in a subsample of 527 participants on an intention-to-treat basis. Changes in cognitive score were calculated as a composite measure using the average of Z scores for the following tests: Mini Mental State Examination orientation items, Free and Cued Selective Reminding Test (sum of free and total recall scores), category fluency, and Digit Symbol Substitution Test. Intervention effects on 3-year change in p-tau181 concentration were estimated by use of a linear mixed model with centre-specific random intercepts. FINDINGS: Recruitment took place between May 30, 2008, and Feb 24, 2011. Median baseline plasma p-tau181 was 8·8 pg/mL (IQR 6·7-11·9) in the total sample, and significantly higher in older individuals, men, APOE ε4 carriers, and participants with renal dysfunction or a positive PET amyloid scan. During 3-year follow-up, individuals with raised baseline p-tau181 underwent greater cognitive decline (eg, mean difference in 3-year change on the composite cognitive score between control group participants with normal and abnormal baseline levels of p-tau was -0·34 [effect size -0·52; 95% CI -0·61 to 0·07] in the fully adjusted model using a 12·4 pg/mL cutoff for abnormal baseline p-tau181), but there were no intervention effects on change in p-tau181 either in this subgroup or the total population, and no effect on cognitive change in individuals with raised baseline p-tau181 (eg, in the fully adjusted model using the 12·4 pg/mL cutoff for p-tau181 abnormality, the mean difference [95% CI] in this subgroup in 3-year decline on the composite cognitive score between the control group and the multidomain + omega-3 group, the omega-3 group, and the multidomain intervention group, was, respectively: 0·13 [-0·21 to 0·47], 0·03 [-0·30 to 0·36], and 0·10 [-0·26 to 0·46]). Surprisingly, individuals with raised baseline p-tau181 showed a decrease in p-tau181 during follow-up (eg, unadjusted mean [95% CI] 3-year change was -3·01 pg/mL (-4·45 to -1·56) in control group subjects with abnormal baseline p-tau181 [using the 12·4 pg/mL abnormal p-tau cutoff]). INTERPRETATION: Our results support the utility of p-tau181 as a prognostic biomarker, but it did not predict or detect intervention effects in this study. Further investigation of its usefulness as a prevention trial outcome measure is required. FUNDING: Toulouse Gérontopôle, French Ministry of Health and Pierre Fabre Research Institute.

Randomised controlled trials for the prevention of cognitive decline or dementia: A systematic review.

Dementia prevention research has progressed rapidly in recent years, with publication of several large lifestyle intervention trials, and renewed interest in pharmacological interventions, notably for individuals with Alzheimer's disease biomarkers, warranting an updated review of results and methodology. We identified 112 completed trials testing the efficacy of single-domain pharmacological (n = 33, 29%), nutritional (n = 27, 24%), physical activity (n = 18, 16%) and cognitive stimulation (n = 13, 12%), or multidomain (n = 22, 20%) interventions on incident dementia, or a relevant intermediate marker (e.g. cognitive function, biomarkers or dementia risk scores) in people without dementia. The earliest trials tested pharmacological interventions or nutritional supplements, but lifestyle interventions predominated in the last decade. In total, 21 (19%) trials demonstrated a clear beneficial effect on the pre-specified primary outcome (or all co-primary outcomes), but only two (10%) were large-scale (testing blood pressure lowering (Syst-Eur) or multidomain (FINGER) interventions on incident dementia and cognitive change in cognitive function, respectively). Of the 116 ongoing trials, 40% (n = 46) are testing multidomain interventions. Recent methodological shifts concern target populations, primary outcome measures, and intervention design, but study design remains constant (parallel group randomised controlled trial). Future trials may consider using adaptive trials or interventions, and more targeted approaches, since certain interventions may be more effective in certain subgroups of the population, and at specific times in the life-course. Efforts should also be made to increase the representativeness and diversity of prevention trial populations.

Telephone and Smartphone-Based Interventions for Cognitive and Cardio-Metabolic Health in Middle-Aged and Older Adults: A Systematic Review.

Purpose: Dementia and cardio-metabolic diseases share many risk factors. Management of these risk factors could contribute to successful aging, including the prevention of cardio-metabolic disease and dementia. The increasing use of smartphones offers an opportunity for remote preventive interventions. We provided a systematic review of telephone and smartphone-based interventions targeting the prevention of cognitive decline, dementia cardio-metabolic diseases or their risk factors among adults aged over 50 years. Patients and Methods: We searched Pubmed and the International Clinical Trials Registry Platform for experimental studies. We used the Cochrane risk-of-bias tool (Version 2) for randomized trials or TREND (Transparent Reporting of Evaluations with Nonrandomized Designs) checklists to assess study quality for completed studies. Results: We analyzed 21 completed (3 for cognition, 18 for cardio-metabolic outcomes) and 50 ongoing studies (23 for cognition, 27 for cardio-metabolic outcomes). Smartphone interventions were used in 26 studies (3 completed, 23 ongoing). Other interventions involved telephone vocal support and text messaging. Few studies were at low risk of bias. There were heterogeneous cognitive and cardio-metabolic outcomes. The highest quality studies found no significant effects on cognition, and inconsistent results for HbA1c, blood pressure or physical activity. The lower quality-studies found effects on global cognition, working memory, memory and language and inconsistent results for clinical, biological or behavioral cardio-metabolic outcomes. Conclusion and Implications: Despite the large number of commercially available mobile health applications, the magnitude of the scientific evidence base remains very limited. Based on published studies, the added value of telephone and smartphone tools for the prevention of cardio-metabolic diseases, cognitive decline or dementia is currently uncertain, but, there are several ongoing studies expected to be completed in the coming years.

Factors Predicting Engagement of Older Adults With a Coach-Supported eHealth Intervention Promoting Lifestyle Change and Associations Between Engagement and Changes in Cardiovascular and Dementia Risk: Secondary Analysis of an 18-Month Multinational Randomized Controlled Trial.

BACKGROUND: Digital health interventions could help to prevent age-related diseases, but little is known about how older adults engage with such interventions, especially in the long term, or whether engagement is associated with changes in clinical, behavioral, or biological outcomes in this population. Disparities in engagement levels with digital health interventions may exist among older people and be associated with health inequalities. OBJECTIVE: This study aimed to describe older adults' engagement with an eHealth intervention, identify factors associated with engagement, and examine associations between engagement and changes in cardiovascular and dementia risk factors (blood pressure, cholesterol, BMI, physical activity, diet, and cardiovascular and dementia risk scores). METHODS: This was a secondary analysis of the 18-month randomized controlled Healthy Ageing Through Internet Counselling in the Elderly trial of a tailored internet-based intervention encouraging behavior changes, with remote support from a lifestyle coach, to reduce cardiovascular and cognitive decline risk in 2724 individuals aged ≥65 years, recruited offline in the Netherlands, Finland, and France. Engagement was assessed via log-in frequency, number of lifestyle goals set, measurements entered and messages sent to coaches, and percentage of education materials read. Clinical and biological data were collected during in-person visits at baseline and 18 months. Lifestyle data were self-reported on a web-based platform. RESULTS: Of the 1389 intervention group participants, 1194 (85.96%) sent at least one message. They logged in a median of 29 times, and set a median of 1 goal. Higher engagement was associated with significantly greater improvement in biological and behavioral risk factors, with evidence of a dose-response effect. Compared with the control group, the adjusted mean difference (95% CI) in 18-month change in the primary outcome, a composite z-score comprising blood pressure, BMI, and cholesterol, was -0.08 (-0.12 to -0.03), -0.04 (-0.08 to 0.00), and 0.00 (-0.08 to 0.08) in the high, moderate, and low engagement groups, respectively. Low engagers showed no improvement in any outcome measures compared with the control group. Participants not using a computer regularly before the study engaged much less with the intervention than those using a computer up to 7 (adjusted odds ratio 5.39, 95% CI 2.66-10.95) or ≥7 hours per week (adjusted odds ratio 6.58, 95% CI 3.21-13.49). Those already working on or with short-term plans for lifestyle improvement at baseline, and with better cognition, engaged more. CONCLUSIONS: Greater engagement with an eHealth lifestyle intervention was associated with greater improvement in risk factors in older adults. However, those with limited computer experience, who tended to have a lower level of education, or who had poorer cognition engaged less. Additional support or forms of intervention delivery for such individuals could help minimize potential health inequalities associated with the use of digital health interventions in older people.

One-Year Impact of COVID-19 Lockdown-Related Factors on Cardiovascular Risk and Mental Health: A Population-Based Cohort Study.

Lockdown measures have obvious psychological impacts, which could, in turn, increase cardiovascular risk. We assessed the association between lockdown-related factors and the worsening of cardiovascular risk, incident anxiety and depression during 12 months' follow-up. During lockdown (April-May 2020), 534 subjects, aged 50-89 years, were included in the PSYCOV-CV study (NCT04397835) and followed for up to 12 months post-lockdown. We found that participants with symptoms of depression during lockdown were more likely to report increased cardiovascular drug treatment (Odds-Ratio (OR) = 5.08 (1.78-14.5), p = 0.002), decreased physical activity (OR = 1.76 (1.10-2.82), p = 0.019) and weight gain (OR = 1.85 (1.08-3.17), p = 0.024) after lockdown. Moreover, changes in sleep patterns (OR = 2.35 (1.13-4.88), p = 0.022) or living in a rural area during lockdown (OR = 1.70 (0.96-3.03, p = 0.069) were associated with higher incident depression, whereas a better relationship with one's partner during lockdown was associated with less incident depression (OR = 0.56 (0.29-1.08), p = 0.084). Finally, we found that continuing to work during lockdown in a role requiring in-person contact with the public (such as cashiers, nurses or physicians) was associated with more incident anxiety after lockdown (OR = 3.38 (1.12-10.2), p = 0.031). Interestingly, decreased consumption of alcohol during lockdown was associated with less incident anxiety (OR = 0.30 (0.10-0.90), p = 0.032). Our study, conducted in a representative sample of an age group at increased risk of both cardiovascular disease and severe COVID-19, increases the understanding of modifiable factors associated with the health impacts of lockdown measures.

Is more always better? Dose effect in a multidomain intervention in older adults at risk of dementia.

BACKGROUND: Little is known regarding the dose-response function in multidomain interventions for dementia prevention. METHOD: The Multidomain Alzheimer Preventive Trial is a 3-year randomized controlled trial comprising cognitive training, physical activity, nutrition, and omega-3 polyunsaturated fatty acids for at-risk older adults. The dose delivered (number of sessions attended) was modeled against global cognition, memory, and fluency in 749 participants. Interaction effects were assessed for age, sex, education, dementia score (CAIDE), frailty score, and apolipoprotein E (APOE) ε4 status. RESULTS: The dose-response models were non-linear functions indicating benefits up to about 12 to 14 training hours or 15 to 20 multidomain sessions followed by a plateau. Participants who benefited from a higher dose included women, younger participants, frail individuals, and those with lower education or lower risk of dementia. DISCUSSION: The non-linear function indicates that a higher dose is not necessarily better in multidomain interventions. The optimal dose was about half of the potentially available sessions.

The effect of adherence on cognition in a multidomain lifestyle intervention (FINGER).

INTRODUCTION: Lifestyle interventions may prevent cognitive decline, but the sufficient dose of intervention activities and lifestyle changes is unknown. We investigated how intervention adherence affects cognition in the FINGER trial (pre-specified subgroup analyses). METHODS: FINGER is a multicenter randomized controlled trial examining the efficacy of multidomain lifestyle intervention (ClinicalTrials.gov NCT01041989). A total of 1260 participants aged 60 to 77 with increased dementia risk were randomized to a lifestyle intervention and control groups. Percentage of completed intervention sessions, and change in multidomain lifestyle score (self-reported diet; physical, cognitive, and social activity; vascular risk) were examined in relation to change in Neuropsychological Test Battery (NTB) scores. RESULTS: Active participation was associated with better trajectories in NTB total and all cognitive subdomains. Improvement in lifestyle was associated with improvement in NTB total and executive function. DISCUSSION: Multidomain lifestyle changes are beneficial for cognitive functioning, but future interventions should be intensive enough, and supporting adherence is essential.

Cognitive decline as an outcome and marker of progression toward dementia, in early preventive trials.

INTRODUCTION: Recent Food and Drug Administration guidance endorses cognitive assessment as a possible primary endpoint for early trials for Alzheimer's disease but emphasizes the need for certainty regarding the relationship with progression to dementia. METHODS: We compared the validity of the 2-year change (Y0-Y2) of 11 markers of neuropsychological and functional abilities for the prediction of incident dementia over the following 3 years (Y2-Y5), in 860 subjects aged 70 years or older, who consulted for memory loss and were included in the "GuidAge" prevention trial. RESULTS: The Free and Cued Selective Reminding Test-Free Recall (FCSRT-FR) score showed the most predictive 2-year change (area under the curve = 0.72 95% confidence interval = 0.64;0.81). Changes in other subscores of the FCSRT, verbal fluencies tasks, and composite cognitive score were also significantly predictive. Conversely, 2-year change of Mini-Mental State Examination, Trail Making test (TMT)-A, TMT-B, Clinical Dementia Rating Sum of Boxes, and Instrumental Activities of Daily Living scores did not significantly predict occurrence of dementia. CONCLUSION: The FCSRT, the Fluency Task, and the composite cognitive score appear to be good cognitive markers of progression toward dementia in early prevention trials.

Disparities in the participation and adherence of older adults in lifestyle-based multidomain dementia prevention and the motivational role of perceived disease risk and intervention benefits: an observational ancillary study to a randomised controlled trial.

BACKGROUND: Preventive interventions for dementia are urgently needed and must be tested in randomised controlled trials (RCTs). Selection (volunteer) bias may limit efficacy, particularly in trials testing multidomain interventions and may also be indicative of disparities in intervention uptake in real-world settings. We identified factors associated with participation and adherence in a 3-year RCT of multidomain lifestyle intervention and/or omega-3 supplementation for prevention of cognitive decline and explored reasons for (non-) participation. METHODS: Ancillary study during recruitment and follow-up of the 3-year Multidomain Alzheimer Preventive Trial (MAPT) conducted in in 13 memory centres in France and Monaco, involving 1630 community-dwelling dementia-free individuals aged ≥ 70 who were pre-screened for MAPT (1270 participated in MAPT; 360 declined to participate). RESULTS: Response rates were 76% amongst MAPT participants and 53% amongst non-participants. Older individuals (odds ratio 0.94 [95% confidence interval 0.91-0.98] and those with higher anxiety (0.61 [0.47-0.79]) were less likely to participate in the trial. Those with higher income (4.42 [2.12-9.19]) and family history (1.60 [1.10-2.32]) or greater fear (1.73 [1.30-2.29]) of dementia were more likely to participate, as were those recruited via an intermediary (e.g. pension funds, local Alzheimer's associations, University of the 3rd Age, sports clubs) (2.15 [1.45-3.20]). MAPT participants living in larger towns (0.71 [0.55-0.92]) and with higher depressive symptoms (0.94 [0.90-0.99]) were less likely to adhere to the interventions. Greater perceived social support (1.21 [1.03-1.43]) and cognitive function (1.37 [1.13-1.67]) predicted better adherence. Descriptively, the most frequent reasons for accepting and refusing to participate were, respectively, altruism and logistical constraints, but underlying motivations mainly related to (lack of) perceived benefits. CONCLUSIONS: Disparities in uptake of health interventions persist in older age. Those most at risk of dementia may not participate in or adhere to preventive interventions. Barriers to implementing lifestyle changes for dementia prevention include lack of knowledge about potential benefits, lack of support networks, and (perceived) financial costs. TRIAL REGISTRATION: NCT00672685 (ClinicalTrials.gov).

Prevention of dementia using mobile phone applications (PRODEMOS): protocol for an international randomised controlled trial.

INTRODUCTION: Profiles of high risk for future dementia are well understood and are likely to concern mostly those in low-income and middle-income countries and people at greater disadvantage in high-income countries. Approximately 30%-40% of dementia cases have been estimated to be attributed to modifiable risk factors, including hypertension, smoking and sedentary lifestyle. Tailored interventions targeting these risk factors can potentially prevent or delay the onset of dementia. Mobile health (mHealth) improves accessibility of such prevention strategies in hard-to-reach populations while at the same time tailoring such approaches. In the current study, we will investigate the effectiveness and implementation of a coach-supported mHealth intervention, targeting dementia risk factors, to reduce dementia risk. METHODS AND ANALYSIS: The prevention of dementia using mobile phone applications (PRODEMOS) randomised controlled trial will follow an effectiveness-implementation hybrid design, taking place in the UK and China. People are eligible if they are 55-75 years old, of low socioeconomic status (UK) or from the general population (China); have ≥2 dementia risk factors; and own a smartphone. 2400 participants will be randomised to either a coach-supported, interactive mHealth platform, facilitating self-management of dementia risk factors, or a static control platform. The intervention and follow-up period will be 18 months. The primary effectiveness outcome is change in the previously validated Cardiovascular Risk Factors, Ageing and Incidence of Dementia dementia risk score. The main secondary outcomes include improvement of individual risk factors and cost-effectiveness. Implementation outcomes include acceptability, adoption, feasibility and sustainability of the intervention. ETHICS AND DISSEMINATION: The PRODEMOS trial is sponsored in the UK by the University of Cambridge and is granted ethical approval by the London-Brighton and Sussex Research Ethics Committee (reference: 20/LO/01440). In China, the trial is approved by the medical ethics committees of Capital Medical University, Beijing Tiantan Hospital, Beijing Geriatric Hospital, Chinese People's Liberation Army General Hospital, Taishan Medical University and Xuanwu Hospital. Results will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: ISRCTN15986016.

Design and Development of a Mobile Health (mHealth) Platform for Dementia Prevention in the Prevention of Dementia by Mobile Phone Applications (PRODEMOS) Project.

Background: Mobile health (mHealth) has the potential to bring preventive healthcare within reach of populations with limited access to preventive services, by delivering personalized support at low cost. Although numerous mHealth interventions are available, very few have been developed following an evidence-based rationale or have been tested for efficacy. This article describes the systematic development of a coach-supported mHealth application to improve healthy lifestyles for the prevention of dementia and cardiovascular disease in the United Kingdom (UK) and China. Methods: Development of the Prevention of Dementia by Mobile Phone applications (PRODEMOS) platform built upon the experiences with the Healthy Aging Through Internet Counseling in the Elderly (HATICE) eHealth platform. In the conceptualization phase, experiences from the HATICE trial and needs and wishes of the PRODEMOS target population were assessed through semi-structured interviews and focus group sessions. Initial technical development of the platform was based on these findings and took place in consecutive sprint sessions. Finally, during the evaluation and adaptation phase, functionality and usability of the platform were evaluated during pilot studies in UK and China. Results: The PRODEMOS mHealth platform facilitates self-management of a healthy lifestyle by goal setting, progress monitoring, and educational materials on healthy lifestyles. Participants receive remote coaching through a chat functionality. Based on lessons learned from the HATICE study and end-users, we made the intervention easy-to-use and included features to personalize the intervention. Following the pilot studies, in which in total 77 people used the mobile application for 6 weeks, the application was made more intuitive, and we improved its functionalities. Conclusion: Early involvement of end-users in the development process and during evaluation phases improved acceptability of the mHealth intervention. The actual use and usability of the PRODEMOS intervention will be assessed during the ongoing PRODEMOS randomized controlled trial, taking a dual focus on effectiveness and implementation outcomes.

Kidney Function and Cognitive Decline in Older Adults: Examining the Role of Neurodegeneration.

BACKGROUND/OBJECTIVES: Cognitive decline associated with impaired kidney function might involve neurodegeneration. Our objectives were to evaluate the longitudinal association between kidney function and cognitive decline in older adults and to assess the involvement of cortical beta-amyloid and hippocampal atrophy (features of Alzheimer's disease (AD)) in this association. DESIGN: Secondary analysis of the randomized controlled Multidomain Alzheimer Preventive Trial (MAPT). SETTINGS: Thirteen memory centers (France and Monaco, 2008-2016). PARTICIPANTS: A total of 1,334 community-dwellers >70 years old without dementia at baseline. MEASUREMENTS: We estimated glomerular filtration rate (eGFR) from serum creatinine using CKD-Epi equation. Cognition was assessed at baseline, 6, 12, 24, 36, 48, and 60 months using a composite Z-score designed for MAPT. The Clinical Dementia Rating (CDR) score was used to assess cognition and functional independence. We examined the association between eGFR and (1) evolution of the composite cognitive Z-score using mixed-effect models and (2) progression on CDR using Cox models and mixed-effect models. Adjustments were made for age, sex, education, ApoE genotype, cardiovascular risk factors and disease, hippocampal volume (measured with magnetic resonance), and cortical beta-amyloid (measured with positron emission tomography). RESULTS: Median (IQR) eGFR was 73(60-84) mL/min/1.73 m2 . Two hundred sixty-nine participants experienced progression on CDR score during follow-up. eGFR<60 was significantly associated with progression on CDR score (adjusted hazard ratio (aHR) = 1.35, 95% CI 1.01-1.80) and with both the cognitive and functional independence components of CDR, but not with the evolution of the composite cognitive Z-score (adjusted ß-coefficient -0.004, 95% CI -0.014; 0.006). Associations were not modified after further adjustment for beta-amyloid (subsample: n = 252) and hippocampal volume (subsample: n = 270). CONCLUSIONS: We did not find a mild to moderate renal insufficiency to be associated with brain imaging features of AD, and our results do not support the involvement of AD mechanisms in the incidence of cognitive impairment and functional decline associated with chronic kidney disease.

Dementia risk scores as surrogate outcomes for lifestyle-based multidomain prevention trials-rationale, preliminary evidence and challenges.

INTRODUCTION: Although not designed as such, dementia risk scores might be useful surrogate outcomes for dementia prevention trials. Their suitability may be improved by using continuous scoring systems, taking into account all changes in risk factors, not only those crossing cut-off values. METHODS: In three large multidomain dementia prevention trials with 1.5 to 2 years of follow-up (Multidomain Alzheimer Preventive Trial, Prevention of Dementia by Intensive Vascular Care and Healthy Ageing Through Internet Counselling in the Elderly) we assessed (1) responsiveness (sensitivity to change) and (2) actual and simulated intervention effects of the original and crude/weighted z-score versions of the cardiovascular risk factors, aging and incidence of dementia, and Lifestyle for Brain Health scores. RESULTS: All versions of the risk scores were generally responsive, and able to detect small though statistically significant between-group differences after multidomain interventions. Simulated intervention effects were well detected in z-score versions as well as in the original scores. DISCUSSION: Dementia risk scores and their z-score versions show potential as surrogate outcomes. How changes in risk scores affect dementia remains to be determined.

Attitudes of at-risk older adults about prevention of cardiovascular disease and dementia using eHealth: a qualitative study in a European context.

OBJECTIVES: Prevention of cardiovascular disease (CVD) and dementia is a key health priority among older adults. Understanding individuals' attitudes to, the prevention of these conditions, particularly when delivered through novel eHealth tools, could help in designing effective prevention programmes. The aim of the study was to explore the attitudes of older adults at increased risk of CVD and dementia regarding engagement in eHealth self-management prevention programmes, and to describe the facilitators and barriers. DESIGN: A qualitative research approach was used. Data were collected through eight focus groups in Finland, France and the Netherlands. Data were analysed following the principles of grounded theory. SETTING AND PARTICIPANTS: Forty-four community-dwellers aged 65+ at risk of CVD were recruited from a previous trial cohort in Finland, and through general practices in France and the Netherlands. RESULTS: The study identified three categories: access to reliable information, trust in the healthcare providers and burden and stigma of dementia. A core category was also identified: the interactive process of the three categories influencing engagement in self-management prevention programme. The categories were interconnected through an interactive process and influenced by the local healthcare culture and context which shaped them differently, becoming either facilitators or barriers to engage in eHealth self-management prevention programmes. CONCLUSIONS: The study emphasises the importance of considering the interactions between the identified categories in this study, grounded in the local healthcare culture and context in further developments of eHealth self-management interventions that aim to prevent CVD and dementia. TRIAL REGISTRATION NUMBER: ISRCTN48151589.

Pooling individual participant data from randomized controlled trials: Exploring potential loss of information.

BACKGROUND: Pooling individual participant data to enable pooled analyses is often complicated by diversity in variables across available datasets. Therefore, recoding original variables is often necessary to build a pooled dataset. We aimed to quantify how much information is lost in this process and to what extent this jeopardizes validity of analyses results. METHODS: Data were derived from a platform that was developed to pool data from three randomized controlled trials on the effect of treatment of cardiovascular risk factors on cognitive decline or dementia. We quantified loss of information using the R-squared of linear regression models with pooled variables as a function of their original variable(s). In case the R-squared was below 0.8, we additionally explored the potential impact of loss of information for future analyses. We did this second step by comparing whether the Beta coefficient of the predictor differed more than 10% when adding original or recoded variables as a confounder in a linear regression model. In a simulation we randomly sampled numbers, recoded those < = 1000 to 0 and those >1000 to 1 and varied the range of the continuous variable, the ratio of recoded zeroes to recoded ones, or both, and again extracted the R-squared from linear models to quantify information loss. RESULTS: The R-squared was below 0.8 for 8 out of 91 recoded variables. In 4 cases this had a substantial impact on the regression models, particularly when a continuous variable was recoded into a discrete variable. Our simulation showed that the least information is lost when the ratio of recoded zeroes to ones is 1:1. CONCLUSIONS: Large, pooled datasets provide great opportunities, justifying the efforts for data harmonization. Still, caution is warranted when using recoded variables which variance is explained limitedly by their original variables as this may jeopardize the validity of study results.