36 Hong Kong Med J Vol 12 No 4 Supplement 2 August 2006 HEALTH SERVICES RESEARCH FUND – HEALTH CARE AND PROMOTION FUND Hong Kong Med J 2006;12 (Suppl 2):S36-9 Prevention of osteoporotic fractures among high-risk groups of post- menopausal women Department of Orthopaedics and Traumatology, The Chinese University of Hong Kong PC Leung, L Qin, SK Au HCPF project number: 298104 Principal applicant and corresponding author: Prof PC Leung Department of Orthopaedics and Traumatology The Chinese University of Hong Kong Shatin, NT Hong Kong SAR, China Tel: (852) 2632 2723 Fax: (852) 2686 8463 Email: pingcleung@cuhk.edu.hk PC Leung  L Qin  SK Au  Introduction Menopausal and age-related loss of bone mass and its associated fractures is a universal health problem among post-menopausal women, especially high-risk patients with established osteoporosis (PEO) (low bone mineral density [BMD] and one or more fragility fractures) and fast bone loss. 1 The prevalence of osteoporosis among the Chinese elderly in Hong Kong, as evidenced by osteoporotic fractures, is high. Osteoporotic fractures are the fifth most commonly occurring condition in a subject’s medical history. 2 Anti-bone resorptive drugs are effective in the treatment of high-risk Caucasian patients. 1,3 Non-pharmacological approaches such as physical exercise are beneficial for prevention of bone loss and falls among the elderly. 4 Aims and objectives The aim of this study was to investigate the effects of two popular anti-resorptive drugs (alendronate and calcitonin) and Tai Chi exercise on prevention of bone loss and reduction of fall-related intrinsic risk factors in Hong Kong Chinese post- menopausal women identified with established osteoporosis or as fast bone losers. Materials and methods Setting and subjects This study was conducted from July 1999 to December 2002. Post-menopausal Chinese women, identified as having established osteoporosis (with a Colles’ fracture) and as fast bone losers (with annual trabecular bone loss at the non- dominant distal radius over 3%) were recruited. Women on drug treatment or diagnosed with diseases known to affect spontaneous bone loss and women who had more than 2 hours of regular exercise per week were excluded. The subjects were randomised into four groups for both fast bone losers (n=86) and women with established osteoporosis (n=85). Grouping and interventions 1. Alendronate group: 10 mg alendronate plus 1200 mg of calcium supplement per day. Subjects maintained their original lifestyle. 2. Calcitonin (nasal spray) group: 200 IU/day of salmon nasal spray plus 1200 mg of calcium supplement per day. Subjects maintained their original lifestyle. 3. Standard exercise group: subjects participated in regular Tai Chi exercise, 45 min/day, 3 days/week, which was modified to enable all subjects to practise (http://www.no-fall.org). Calcium was also supplemented (1200 mg/day). 4. Placebo-control group: subjects maintained their original lifestyle. Calcium was also supplemented (1200 mg/day). Main outcome measures BMD measurements 1. Dual-energy X-ray absorptiometry (DXA)—the BMD in g/cm 2 was measured at the spine and the non-dominant hip. Key Messages 1. When bone mineral density and its changes are used as an endpoint measure, anti- resorptive drugs—alendronate and calcitonin—demonstrate better treatment effects com- pared with exercise or calcium supplements alone in high-risk patients. 2. Tai Chi exercise was beneficial for both the retardation of bone loss and enhancement of body function, including muscle strength and body balance factors, which may be associated with a better chance of fall pre- vention for high-risk subjects.