engleski

Discriminatory Ability of Calcaneal Quantitative Ultrasound in the Assessment of Bone Status in Patients with Inflammatory Bowel Disease

A high incidence of bone disease in patients with inflammatory bowel disease (IBD) requires frequent monitoring of skeletal status, and for that reason evaluation of radiation free technology is an issue of interest. Our objective was to appraise the parameters of calcaneal quantitative ultrasound (QUS): broadband ultrasound attenuation (BUA), speed of sound (SOS) and stiffness index (QUI), and establish their t-score values to investigate discriminatory ability of QUS in IBD patients with metabolic bone disease. The study included 126 patients (Crohn's disease n=94, and ulcerative colitis n=32) and 228 healthy volunteers. Bone status was evaluated on the same day by calcaneal QUS and dual-energy x-ray absorptiometry (DXA). Based on spine (L1-L4) and hip DXA patients were divided into subgroups with normal bone status (41%) and those with osteopenia (39%) or osteoporosis (20%). All QUS measurements were lower in patients compared with reference population (BUA p<0.0004 ; SOS p<0.000001 ; QUI p<0.000001) and correlated significantly but inversely with disease duration (r=-0.3, p=0.002). There was no difference with respect to type of disease (Crohn's disease or ulcerative colitis) or corticosteroid therapy. QUS parameters were significantly lower in patients with (n=28) than in those without a history of bone fracture (n=98) (t-scores: BUA -2.0 vs. -1.3, p=0.008 ; SOS -2.1 vs. -1.4, p=0.02: QUI -2.3 vs. -1.5, p=0.009). Patients with t-score <-1.0 scanned by DXA were classified as bone disease. The sensitivity of QUS to identify bone disease was 93% ; indicating 7% of patients with verified bone disease to be misclassify as false negative. The specificity of 63% showed that 37% of individuals with normal bone status were QUS classified as false positive. The sensitivity of QUS to detect osteopenia was 84% and 72% for osteoporosis. Calcaneal QUS showed poor agreement with bone status scanned by DXA and a low discriminatory power between osteopenia and osteoporosis in patients with inflammatory bowel disease. However, QUS successfully identified patients with previous fragile fractures.

Inflammatory bowel disease; Metabolic bone disease; Calcaneal quantitative ultrasound; Dual-energy x-ray absorptiometry; Specificity; Sensitivity

nije evidentirano