Background: Multidomain, technology-based interventions represent a promising approach to dementia prevention by simultaneously targeting cognitive, physical, and social domains. Exercogs® is a novel exergaming platform combining augmented reality (AR) and gamification, designed to deliver tailored, interactive, and multidomain training. This study aims to evaluate the feasibility, safety, and efficacy of Exercogs® when implemented as part of a community-based dementia prevention program for older adults at risk.

Methods: This is a randomized, controlled, assessor-blind, parallel-group, multicenter trial. One hundred and fifty community-dwelling adults, aged 55 years or older, with at least one modifiable dementia risk factor, will be randomly assigned (1:1) to either the Exercogs® intervention group or the active control group. Both groups will complete 60-minute supervised sessions three times per week for 24 weeks. The Exercogs® program integrates cognitive (e.g., attention, memory, and executive function), physical (e.g., balance, gait, and coordination), and social (e.g., cooperative and competitive) activities within a gamified AR environment. The difficulty levels are adaptable to the participants' individual abilities. The control group will perform equivalent non-AR exercises, i.e., the control group will receive a conventional multidomain group program with the same frequency and duration. Outcomes will be assessed at baseline, 12 weeks, 24 weeks (end of intervention), and 4 and 8 weeks post-intervention. The co-primary endpoints are changes in global cognition (Montreal Cognitive Assessment-Portuguese Version, MoCA-PT), physical performance (Short Physical Performance Battery, SPPB), and social participation (World Health Organization Disability Assessment Schedule, WHODAS 2.0). Secondary outcomes include usability (System Usability Scale, SUS-PT; Exercogs® group only), health-related quality of life (EQ-5D-5L), safety (adverse events, including falls, dizziness, and fatigue), and changes in modifiable risk load. Exploratory outcomes include digital engagement and in-game performance metrics automatically captured by the Exercogs® platform. Feasibility will be assessed by session adherence (≥70% completion).

Results: The protocol has been approved by the Casa de Saúde da Idanha Ethics Committee (Nº6/2025) and funded by the Instituto da Segurança Social, I.P. Preliminary findings are expected in 2026 and will provide comprehensive evidence on the efficacy, feasibility, usability, and safety of Exercogs® as a multidomain digital intervention.

Conclusions: This trial will evaluate a scalable, technology-driven, multidomain intervention for older adults at risk of dementia, integrating cognitive, physical, and social training within an AR environment and gamification. If effective, Exercogs® could serve as a model for community-based dementia prevention and inform public health strategies for healthy aging.

Background:

Age-related cognitive decline is a major public health challenge, increasingly burdening healthcare and social protection systems. Large-scale multidomain trials, including FINGER, MAPT, and preDIVA, have shown that multicomponent interventions are more effective in reducing dementia risk than single-domain approaches. The latest Lancet Commission identified 14 modifiable risk factors accounting for up to 45% of potentially preventable dementia cases, highlighting the importance of coordinated prevention strategies. Recent research also emphasizes the role of social and structural determinants, such as socioeconomic factors, HIV infection, and gender, in expanding the global applicability of prevention models. Notably, evidence suggests that multidomain interventions may benefit individuals irrespective of genetic risk.

Given dementia's multifactorial etiology, multidomain interventions are particularly well-suited to address interrelated risk factors, including physical inactivity, social isolation, and cognitive underuse, by simultaneously targeting biological, behavioral, and psychosocial determinants of cognitive aging. Advances in digital health technologies have expanded the reach and feasibility of such programs. Digital tools, including computerized cognitive training and exergaming, have shown promise in improving cognition, physical function, and social engagement among older adults. Extended reality technologies, including virtual and augmented reality (AR), further enhance these interventions by providing immersive, interactive, and adaptive environments that improve motivation, adherence, and learning.

Integrating gamification into AR-based exergames can transform solitary exercises into socially engaging activities, supporting mood, social interaction, and psychological well-being. Systematic reviews confirm benefits across cognitive, physical, and emotional domains, including memory, attention, executive function, mobility, balance, strength, and overall functional capacity. Social (multiplayer) exergames, in particular, offer engaging experiences that support aerobic exercise and enhance social well-being, including reduced loneliness, increased social connection, and more positive attitudes toward others. Feasibility studies further indicate high acceptability, safety, and applicability in home and community settings, with minimal spatial requirements. Nevertheless, while AR-based interventions appear effective, small sample sizes and high heterogeneity limit the generalizability of current findings, emphasizing the need for larger, more standardized trials.

Despite promising preliminary evidence, rigorous trials evaluating AR-based gamified interventions in community-dwelling older adults remain scarce, particularly those assessing multidomain outcomes spanning cognitive, physical, and social dimensions. There is also a need to systematically examine engagement, usability, and real-world applicability to ensure that such interventions can be feasibly scaled and adapted to individual abilities. Delivering a multidomain program through a gamified AR platform could provide an engaging, adaptive, and scalable approach to enhancing cognitive, physical, and social functioning in older adults at risk of cognitive decline. Accordingly, this trial aims to evaluate the efficacy and safety of a gamified AR-based multidomain intervention (Exercogs®) on global cognition, physical performance, and social participation (MoCA, SPPB, WHODAS 2.0).

Objectives and Hypotheses:

This study aims to assess the efficacy and feasibility of Exercogs®, a digital multidomain intervention combining AR and gamification to integrate cognitive, physical, and social training, for the prevention of cognitive decline in community-dwelling older adults.

H1: Participants receiving Exercogs® will show greater improvements in cognitive performance, physical function, and social participation compared with the control group after 24 weeks.

H2: Intervention effects will be maintained at follow-up (4-8 weeks post-intervention).

H3: The number of baseline modifiable risk factors (risk burden) will moderate the magnitude of intervention effects.

Methods in brief:

We will conduct a randomized, controlled, rater-blind, parallel-group, multicenter clinical trial. Participants will undergo assessments at baseline, 12 weeks, 24 weeks (end of intervention), and follow-up (4 and 8 weeks post-intervention).

Exercogs® Group (A): Participants will undertake structured 60-minute sessions three times per week for 24 weeks. Each session integrates physical training (balance, gait, and coordination exercises), cognitive stimulation (attention, memory, and executive functions), and social engagement activities (cooperative and competitive tasks). All activities are delivered within a gamified AR environment designed to enhance engagement and adapt difficulty to individual abilities. The intervention follows a predefined, progressive protocol tailored to each participant's performance.

Control Group (B): Participants will engage in a conventional multidomain program matched for frequency and duration (60 minutes, three times per week, 24 weeks), comprising standard physical, cognitive, and social exercises without AR or gamification.

After providing written informed consent, eligible community-dwelling adults aged 55 years or older with at least one modifiable risk factor for dementia will undergo a comprehensive baseline assessment. Demographic, clinical, and medication information will be collected through structured interviews. Outcome assessments will be conducted by assessors blinded to group allocation and independent of the intervention team, minimizing the risk of assessment bias. The same assessors will perform all evaluations throughout the study to ensure consistency. Session adherence, as well as any missed sessions, adverse events, or protocol deviations, will be recorded in real time using standardized reporting forms. Adherence for the Exercogs® group will be monitored via automated platform logs, whereas attendance for both groups will also be tracked using therapist-completed diaries.

Expected impact:

This study will provide robust evidence on the efficacy, usability, and scalability of Exercogs® as a digital, multidomain preventive intervention for adults aged 55 years and older who are at risk for dementia. The findings may inform the integration of digital health solutions into community- and national-level dementia prevention programs, supporting the implementation of evidence-based strategies for healthy aging.

If successful, this study will be the first randomized controlled trial to evaluate a gamified, AR-based multidomain intervention for the prevention of cognitive decline in community-dwelling adults, addressing cognitive, physical, and social domains simultaneously, with strong potential for adoption within Portugal's public health system.

Inclusion Criteria:

• Age 55 years or older
• Presence of ≥1 modifiable risk factor according to the Lancet Commission on Dementia Prevention, Intervention, and Care (2024): low education, untreated hearing or visual loss, hypertension, obesity, smoking, depression, physical inactivity, type 2 diabetes, social isolation, excessive alcohol consumption, history of head trauma, air pollution exposure, high LDL/dyslipidemia; additional social and structural determinants, including poverty, income inequality, wealth shocks, and HIV, that may also contribute to risk (Mostert et al., 2025);
• Ability and willingness to participate in 60-minute sessions, three times per week, during the 24-week intervention period;
• Ability to provide written informed consent, or, in cases of reduced decisional capacity, provision of consent by a legally authorized representative.

Exclusion Criteria:

• Clinical diagnosis of Alzheimer's disease or dementia;
• Severe neurological disorder or unstable medical condition that may interfere with participation;
• Sensory or language deficits that would prevent understanding of instructions or safe participation;
• Current participation in another interventional study that may confound outcomes (e.g., cognitive training, physical exercise, or multidomain rehabilitation);
• Previous experience with Exercogs®.

IPD will not be shared due to participant confidentiality and ethical considerations regarding sensitive health data.

Outcome assessors will be blinded to group allocation, while participants and therapists cannot be blinded due to the nature of the intervention. All participants and therapists will be instructed not to disclose allocation to assessors, and any unblinding events will be recorded and addressed in the analysis.