Osteoporosis and Sarcopenia Prevention in Middle-Aged Population

This initiative is designed to yield substantial and multi-level benefits for the Hong Kong community by pioneering a transformative model of preventive healthcare. It represents the largest randomized controlled trial for osteoporosis and sarcopenia prevention in the region, adopting a comprehensive approach to fracture prevention through innovative fitness, lifestyle, and digital strategies.

The study's primary objective is to evaluate the efficacy of preventing fractures, osteoporosis, and sarcopenia through an incentivized program of fitness and lifestyle modifications in adults aged 40-60. The secondary objectives include: (1) to validate the use of simple, low-cost measures (grip strength and InBody body composition analysis) as reliable proxy indicators for osteoporosis and sarcopenia risk relative to the gold-standard DEXA scan; (2) to develop a formal, standardized clinical protocol for early detection and prevention, including specified DEXA anatomical measurement sites, for use by healthcare professionals in primary and community care settings; (3) to assess changes in exercise behavior, musculoskeletal health, physical function, health literacy, and participant engagement with the digital (AI chatbot) support system; (4) to analyze the cost-effectiveness of the intervention compared to standard care or pharmacological treatment, including an assessment of healthcare utilization and Quality-Adjusted Life Years (QALYs).

After baseline screening and consent, participants are randomly assigned to one of two groups (1:1 ratio) with intention-to-treat principles. The Control Group will receive passive, static support. This involves participating in one initial FUN Day, receiving standard exercise videos, using a passive chatbot for data reporting, undergoing start and end DEXA scans (which require a co-payment), completing a 3-month assessment, and receiving souvenirs at the study start and end. Meanwhile, the Intervention Group will receive active, dynamic support designed to build and reinforce healthy habits. This involves participating in the initial FUN Day, a reinforcement FUN Day at 2 months, nine mandatory structured exercise touchpoints, using an active chatbot with reminders, feedback, and gamification, undergoing start and end DEXA scans (which require a co-payment), completing a 3-month assessment, and receiving ongoing incentives and souvenirs at multiple points. Therefore, researchers will compare between the control and intervention groups to see if intervention can prevent osteoporosis and sarcopenia at a population level.

All participants will undergo a series of assessments at specific timepoints. This includes two DEXA scans (at the study start and in the fourth year, requiring a participant co-payment), InBody composition analysis, and physical health assessments (e.g., grip strength, balance, cardiovascular fitness). These assessments will be performed at baseline (during the first FUN Day), 3 months, 12 months, 24 months, and 36 months. A long-term follow-up will continue for up to 10 years to monitor adverse health events such as falls and fractures. Participants will also complete questionnaires via an AI chatbot at baseline, 3 months, and annually during follow-up. The collected data will encompass health literacy (e.g., osteoporosis/sarcopenia knowledge scores), digital engagement (e.g., chatbot responsiveness), and economic outcomes (e.g., incremental cost per Quality-Adjusted Life Year \[QALY\] gained). Data analysis will employ appropriate statistical methods to compare outcomes between the control and intervention groups across all assessments and timepoints.