071 Different effects of body mass index and physical activity on the risk of ankle, wrist and hip fractures in postmenopausal women

ObjectiveTo compare the relationship between body mass index (BMI) and physical activity for the risk of ankle, wrist and hip fractures in a large prospective study of postmenopausal women in the UK.MethodsIn 1996–2001, women recruited into the Million Women Study completed a self-administered questionnaire asking about body size, physical activity, disease history, and lifestyle and reproductive factors. Incident ankle, wrist and hip fractures were identified through self-report in a follow-up questionnaire completed an average of 3.2 years after recruitment. RRs and CIs for each fracture site in postmenopausal women by BMI and physical activity at recruitment were calculated using Cox regression models, adjusted for socio-economic status, smoking and other health and lifestyle factors.ResultsAmong 599 550 postmenopausal women, 5114 reported an ankle fracture, 8565 reported a wrist fracture, and 754 reported a hip fracture during follow-up. When compared to lean women (BMI