Effectiveness of a Multi-Component Lifestyle Intervention on Cognitive Function and Instrumental Activities of Daily Living in Adults at Risk of Dementia

To determine the effectiveness of a multi-component lifestyle intervention on instrumental activities of daily living and cognitive function in adults at risk of developing dementia.

This is a randomized controlled trial with a parallel design and double-blind protocol, conducted to evaluate the effectiveness of a multi-component lifestyle intervention compared to routine care. Participants will be allocated using stratified randomization based on the type of cognitive impairment, and the sample size is calculated with 90% power and a significance level of 0.01.

This study will be conducted in elderly care centers in Tehran on adults over 55 diagnosed with MCI or SCD, who will be stratified-randomized into intervention and control groups; the trial is double-blind, and allocation is concealed using sealed envelopes.

Adults aged 55 and above who are independent in self-care, have difficulty with at least one IADL, no severe psychiatric or neurological disorders, and meet MCI or SCD criteria will be included; those with physical disabilities, a history of severe mental illness, or unwillingness to participate will be excluded.

The control group will receive routine care provided by elderly care centers. The intervention group, in addition to routine care, will participate in a 6-week multi-component lifestyle program including cognitive training, physical activity, and social engagement. The aim of the intervention is to improve cognitive function and daily activities in older adults at risk of dementia.

Overall cognitive performance score based on MoCA; Instrumental activities of daily living (IADLs) score based on Bayer-ADL questionnaire;

Participants will be allocated to the intervention and control groups in a 1:1 ratio using stratified block randomization. Stratification will be based on cognitive impairment type (MCI or SCD), with blocks of four used to maintain balance between the groups. Separate computer-generated randomization sequences will be prepared for each stratum by an independent individual. Allocation codes will be placed in sequentially numbered, opaque, sealed envelopes. Following enrollment and baseline assessment, the randomization officer will open the next envelope corresponding to the participant’s stratum and inform the principal investigator of the group assignment.

Due to the nature of the intervention, blinding of participants and the interventionist will not be feasible, as they will be aware of the intervention being received or delivered. However, the assessor of participants’ cognitive and daily functioning will remain blinded to group allocation and will not have access to the randomization records. Participants will also be instructed not to disclose their group assignment or details of the intervention during the assessments. The assessor is an occupational therapist with two years of experience in clinical cognitive assessment and certification in administering the MoCA. The intervention will be delivered by an occupational therapist with two years of experience in geriatric care. Any accidental unblinding of the assessor will be documented. In addition, the statistical analyst will receive coded group data and remain blinded to group allocation until the primary analyses have been completed.

De-identified individual participant data (IPD), including key outcomes, demographic variables, and cognitive and functional assessment results, will be made available upon request. Additionally, supporting documentation such as the statistical analysis plan, analysis code (upon request), and clinical outcome reports will be shared. Data will be accessible for up to 3 years post-publication via formal request and with approval from the ethics committee. Access will be granted to qualified researchers for legitimate academic purposes.

Access to de-identified participant data, statistical analysis outputs, and related documents will begin 6 months after publication of the final results and will remain available for a period of 3 years. Access will be granted upon formal request and subject to ethical approval.

Data and related documentation will be made available only to researchers affiliated with recognized academic, medical, or research institutions. Industry-based researchers may also apply, provided they submit a well-defined research proposal, obtain ethics approval, and collaborate with an academic or scientific entity. All data must be used strictly for non-commercial, scientific purposes only.

The shared data may only be used for non-commercial, scientific, and research purposes. Analyses must be limited to secondary research aligned with the original study’s aims or closely related research questions. Meta-analyses, academic training, and systematic reviews are permitted with proper citation. Any use that violates participant privacy, research ethics, or informed consent agreements is strictly prohibited. Data may not be re-shared with third parties without prior written approval. Requirements for data access request: Submission of a formal request with an institutional affiliation letter A detailed research proposal outlining objectives, methodology, and type of intended analyses A valid ethical approval from a recognized ethics committee A signed data use and confidentiality agreement Acceptance of review and possible rejection by the principal research team based on ethical/scientific grounds

Contact Information for Data Access Requests: Applicants interested in accessing participant data or related study documents may proceed through the following channels (in order of priority): Official email request:

Process for Requesting and Receiving Data/Documents: To access de-identified data or study documentation, applicants must complete the following steps: Submit a formal request via email or post, including: A full research proposal (objectives, methodology, intended analyses) Institutional affiliation letter Ethics committee approval Confidentiality agreement (a template will be provided, if needed) Initial review by the research team within 7 working days, to assess ethical and scientific compatibility Feedback and (if approved) provision of the confidentiality agreement for applicant signature Delivery of data/documents within 10–14 working days of receiving complete documentation and signed agreement ✅ If all documents are submitted properly, the total turnaround time for access is estimated at 2 to 3 working weeks.