Quantitative ultrasound calcaneous measurements: normative data for the Italian population. the ESOPO study

Quantitative ultrasound (QUS) is a reliable technique to evaluate skeletal status, to identify osteoporotic subjects, and to estimate the risk of fractures. The purpose of this study was to generate QUS normative data for Italian females and males aged 60-79 yr participating in the Epidemiologic Study on the Prevalence of Osteoporosis (ESOPO) study, using the Achilles Plus apparatus. ESOPO is a cross-sectional study conducted in 2000, aiming at assessing risk of osteoporosis in a random sample of 11,011 women and 4981 men, representative of the Italian population. All participants were administered a questionnaire on the most relevant risk factors for osteoporosis and fractures; 3 QUS parameters were also measured: broadband ultrasound attenuation (BUA); speed of sound (SOS); and Stiffness Index (SI). We studied the age-dependent changes in QUS values, and their correlation with body size. For both men and women, weight was the variable with the highest correlation with BUA and SI; for SOS, age among women and body mass index (BMI) among men presented the highest correlation coefficients. Average decreases of 3.0% in BUA, 0.8% in SOS, and 9.1% in SI from 60 to 79 yr were detected for females, whereas no significant changes with age in males were observed. Our data show lower QUS values for women, and a decline at a greater rate than in men.