['Heart failure is associated with increased risk of osteoporosis. We evaluated the prevalence and predictors of osteoporosis in hospitalized patients with ADHF using quantitative computed tomography. Osteoporosis and vertebral fracture are prevalent in patients with ADHF and exercise capacity independently predicts bone mass and femoral bone geometry.', 'Heart failure is associated with reduced bone mass and increased risk of osteoporotic fractures. However, the prevalence and predictors of osteoporosis in hospitalized patients with acute decompensated heart failure (ADHF) are not well understood.', 'Sixty-five patients (15 postmenopausal females and 50 males) with ADHF were prospectively and consecutively enrolled. After stabilization of heart failure symptoms, quantitative computed tomography for bone mineral density (BMD) and femoral geometry as well as biochemical, echocardiographic, and cardiopulmonary exercise tests were performed.', 'Fifteen postmenopausal female showed a high prevalence of osteoporosis (40%) and vertebral fracture (53%). Among 50 male patients, 12% had osteoporosis and 32% had osteopenia, while vertebral fracture was found in 12%. Lumbar volumetric BMD (vBMD) was significantly lower in ischemic patients than non-ischemic patients (107.9\u2009±\u200947.5 vs. 145.4\u2009±\u200940.9 mg/cm(3), p\u2009=\u20090.005) in male. Exercise capacity, indicated by peak oxygen consumption (VO2), was significantly associated with lumbar vBMD (r\u2009=\u20090.576, p\u2009<\u20090.001) and total hip areal BMD (aBMD) (r\u2009=\u20090.512, p\u2009=\u20090.001) and cortical thickness of the femur neck (r\u2009=\u20090.544, p\u2009=\u20090.001). When controlled for age, body mass index, N-terminal proBrain natriuretic protein (NT-proBNP), etiology of heart failure, hemoglobin, and thigh circumference, multivariate regression analysis revealed peak VO2 independently predicted lumbar vBMD (β\u2009=\u20090.448, p\u2009=\u20090.031), total hip aBMD (β\u2009=\u20090.547, p\u2009=\u20090.021), and cortical thickness of the femur neck (β\u2009=\u20090.590, p\u2009=\u20090.011).'] Does exercise capacity independently predict bone mineral density and proximal femoral geometry in patients with acute decompensated heart failure?