[Bone mineral density in idiopathic inflammatory myopathies]

The study was undertaken to examine the impact of glucocorticoid therapy (GCT) on mineral bone density (MBD) in patients with idiopathic inflammatory myopathies. Double-energy X-ray absorptiometry was used to determine MBD of the vertebral column and proximal femur in 42 females (30 with the preserved menstrual cycle (PMC), 12 in postmenopause (PMP) with polymyositis/dermatomyositis (PM/DM). All the patients received GCT. A random population sample including 106 females aged 20 to 69 years formed a control group. MBD of the neck of the femur was significantly lower in patients from all age groups, in the lumbar vertebral column in young (20-29 years) and old (over 50 years) females than in the controls. The development of osteoporosis (OP) was more frequently observed in PMP females: OP in the lumbar spine was in 16.7 and 66.7% of the PMC and PMP females, respectively; that in the neck of the femur was in 11 and 33%. There was no relationship between MBD and the specific features of GCT, namely the duration, cumulative dose, and the maximum dose. There was a reduction in MBD in patients with PM/DM on GCT in all age groups, more frequently in PMP patients.