Epidemiological survey of the feasibility of broadband ultrasound attenuation measured using calcaneal quantitative ultrasound to predict the incidence of falls in the middle aged and elderly.

Abstract

We investigated whether calcaneal quantitative ultrasound (QUS-C) is a feasible tool for predicting the incidence of falls. Prospective epidemiological cohort study. Community-dwelling people sampled in central western Taiwan. A cohort of community-dwelling people who were ≥40 years old (men: 524; women: 676) in 2009-2010. Follow-up questionnaires were completed by 186 men and 257 women in 2012. Structured questionnaires and broadband ultrasound attenuation (BUA) data were obtained in 2009-2010 using QUS-C, and follow-up surveys were done in a telephone interview in 2012. Using a binary logistic regression model, the risk factors associated with a new fall during follow-up were analysed with all significant variables from the bivariate comparisons and theoretically important variables. The incidence of falls was determined when the first new fall occurred during the follow-up period. The mean follow-up time was 2.83 years. The total incidence of falls was 28.0 per 1000 person-years for the ≥40 year old group (all participants), 23.3 per 1000 person-years for the 40-70 year old group, and 45.6 per 1000 person-years for the ≥70 year old group. Using multiple logistic regression models, the independent factors were current smoking, living alone, psychiatric drug usage and lower BUA (OR 0.93; 95% CI 0.88 to 0.99, p<0.05) in the ≥70 year old group. The incidence of falls was highest in the ≥70 year old group. Using QUS-C-derived BUA is feasible for predicting the incidence of falls in community-dwelling elderly people aged ≥70 years.