This clinical trial aims to evaluate whether a culturally adapted Snacktivity™ program can improve cognitive function and self-care abilities in patients with Chronic Obstructive Pulmonary Disease (COPD) in Hong Kong.

The main questions it aims to answer are:

1. Does the Snacktivity™ program improve the cognitive function of participants (including both global cognition and targeted subdomains)?
2. Does the program improve participants' self-care abilities?

The study consists of three sequential phases:

Phase 1 (Co-design workshops): Co-design workshops will be conducted with COPD patients, healthcare professionals (nurses, physical therapists, occupational therapists), and family caregivers to culturally adapt the Snacktivity™ program for Hong Kong COPD patients.

Phase 2 (Feasibility Pilot RCT): The adapted program will be tested in a small-scale pilot study to assess its feasibility and short-term clinical effects.

Phase 3 (Full-scale RCT): A full-scale randomised controlled trial will be conducted to evaluate the program's efficacy on the primary and secondary outcomes.

Participants in the intervention group will be asked to:

Participate in the culturally adapted Snacktivity™ program that integrates short, manageable "snacks" of physical activity into daily routines.

Wear an activity tracker to monitor physical activity levels. Complete questionnaires at multiple time points assessing cognitive function, self-care abilities, physical activity levels, self-efficacy, exercise capacity, quality of life, anxiety, and depression.

Researchers will compare the intervention group to an attention control group (receiving usual care with health education) to see if the Snacktivity™ program leads to greater improvements in these outcomes.

1. Background and Research Gaps: Chronic Obstructive Pulmonary Disease (COPD) is a severe global public health issue. In Hong Kong, COPD remains the second most common cause of respiratory hospitalisation, and 56% of COPD patients experience cognitive impairment (CI), which profoundly impacts patients' self-care abilities and quality of life. Despite a robust theoretical foundation, Snacktivity™ has not yet been validated for patients with COPD, and no randomised controlled trials have confirmed its efficacy in enhancing cognitive function and self-care abilities in this population. Two critical research gaps must be addressed: (1) the suitability of its current activity templates for COPD patients, and (2) the feasibility of its implementation in home and workplace settings. Nurses, physical therapists, occupational therapists, and caregivers offer complementary insights into practical challenges, patient-specific barriers, treatment adherence, and resource allocation requirements essential for tailoring the program to Hong Kong's contextual needs.

2 Study Objectives:

1. To explore the feasibility, acceptability, motivating factors, perceived barriers, and preferred formats of the culturally adapted Snacktivity™ program among COPD patients in Hong Kong, and to investigate stakeholders' perspectives, recommendations, and concerns regarding its implementation.
2. To examine the short-term and long-term effects of the culturally adapted Snacktivity™ program on patients' cognitive function and self-care abilities (primary outcomes), as well as on physical activity levels, self-efficacy, exercise capacity, health-related quality of life, anxiety, and depression (secondary outcomes).
3. To explore the overall efficacy and sustainable implementability of the culturally adapted Snacktivity™ program for COPD patients in Hong Kong.

3 Study Design: This is a three-phase sequential study.

1. Phase 1 (Co-design): Co-design workshops will be conducted with COPD patients (n=15), multidisciplinary healthcare professionals (nurses=6, physical therapists=6, occupational therapists=9), and family caregivers (n=6). The aim is to culturally adapt the Snacktivity™ program for Hong Kong COPD patients by gathering diverse perspectives on practical challenges, patient-specific barriers, treatment adherence, and preferred intervention formats. The co-design process follows a four-stage approach: Stage 1 (patient-only workshop), Stage 2 (multi-stakeholder workshop), Stage 3 (WhatsApp asynchronous feedback), and Stage 4 (patient final validation workshop).

2. Phase 2 (Feasibility Pilot RCT): A small-scale pilot randomised controlled trial will be conducted with 50 COPD patients (25 per group) to test the adapted program's feasibility and short-term clinical effects. The intervention lasts 12 weeks, with assessments at baseline and immediately post-intervention. Feasibility outcomes include recruitment and retention rates, intervention adherence, and dropout rates. This phase primarily evaluates feasibility outcomes to inform the design of the subsequent full-scale trial. Clinical outcomes measured in this phase include:

   1. Cognitive function, assessed by the Hong Kong Montreal Cognitive Assessment (HK-MoCA) for global cognition, the Auditory Verbal Learning Test (AVLT) for memory, the Animal Fluency Test (AFT) for language, the Shape Trails Test (STT) for executive function, and the Digit Span Test (DST) for attention.
   2. Self-care abilities, assessed by the Community COPD Self-Management Scale.
   3. Physical activity levels, assessed by the Physical Activity Scale for the Elderly-Chinese version (PASE-C).
   4. Self-efficacy, assessed by the Exercise Self-Regulatory Efficacy Scale-Chinese version (Ex-SRES-Chinese).
   5. Exercise capacity, assessed by the 6-minute walk test (6MWT).
   6. Health-related quality of life, assessed by the COPD Assessment Test (CAT).
   7. Anxiety, assessed by the Generalised Anxiety Disorder-7 (GAD-7) scale.
   8. Depression, assessed by the Patient Health Questionnaire-9 (PHQ-9)

3. Phase 3 (Full-scale RCT): A full-scale randomised controlled trial will be conducted with 160 COPD patients (80 per group) to evaluate the program's efficacy on the primary and secondary outcomes. The intervention duration and frequency remain consistent with Phase 2, but the content will be optimised based on Phase 2 findings. A 3-month post-intervention follow-up will be added to assess long-term effects. Assessments will occur at baseline, immediately post-intervention (Week 12), and 3 months post-intervention. This phase primarily evaluates clinical efficacy, with the same outcome measures and assessment tools as described in Phase 2.

4. Hypotheses:

1. The culturally adapted Snacktivity™ program will demonstrate high feasibility among COPD patients in Hong Kong.
2. COPD patients participating in the culturally adapted Snacktivity™ program will show significant improvements in cognitive function and self-care abilities (primary outcomes), as well as in physical activity levels, self-efficacy, exercise capacity, health-related quality of life, and reductions in anxiety and depression (secondary outcomes), compared to the attention control group.
3. The culturally adapted Snacktivity™ intervention program will exhibit overall effectiveness and sustainable implementability among COPD patients in Hong Kong.

• Inclusion Criteria:

  1. Confirmed diagnosis of COPD in accordance with the 2026 Global Initiative for Chronic Obstructive Lung Disease (GOLD) Guideline, with a post-bronchodilator ratio of FEV₁/FVC < 70%;
  2. Aged ≥ 60 years;
  3. Clinically stable condition;
  4. Score at or below the age- and education-adjusted cutoff (16th percentile) on the Hong Kong Montreal Cognitive Assessment (HK-MoCA) 5-minute Protocol, indicating mild cognitive impairment;
  5. No exercise contraindications;
  6. No active wrist skin conditions that would prevent wearing an activity tracker (Phase 2 & 3);
  7. Willingness to wear an activity tracker during the intervention (Phase 2 & 3);
  8. Possession of a smartphone capable of receiving instant messages (Phase 2 & 3);
  9. Proficiency in Cantonese or Mandarin;
  10. Willingness to provide written informed consent and commitment to trial completion.

• Exclusion Criteria

  1. Receipt of oxygen therapy for ≥ 15 hours per day or requirement for mechanical ventilation;
  2. History of brain injury or stroke;
  3. Presence of severe comorbidities including coronary artery disease, severe hepatic or renal dysfunction;
  4. Diagnosis of psychiatric disorders, deafness, severely limited physical mobility, or inability to cooperate with trial interventions;
  5. For Phase 2 and Phase 3: Use of medications documented to impact cognitive function.

Individual participant data will not be shared as this is a doctoral student-led study conducted as part of a PhD project. The research team does not have the resources or infrastructure to support data sharing at this time. Data access is restricted to the study team to ensure participant confidentiality and protect the privacy of study participants.

The study is single-blinded. The outcomes assessor is masked to group allocation throughout the study. Participants are aware of their group assignment, and intervention providers (researchers delivering the Snacktivity™ program or attention control sessions) are not masked due to the nature of the behavioral intervention.