Bone mineral density improves during 2 years of treatment with bisphosphonates in patients with ankylosing spondylitis

Abstract

Aims: To evaluate whether 2 years of treatment with bisphosphonates in combination with calcium/vitamin D supplements has an effect on lumbar spine and hip bone mineral density (BMD) in ankylosing spondylitis (AS) patients starting tumour necrosis factor-α inhibitors or receiving conventional treatment. Secondly, to explore the development of radiographic vertebral fractures. Methods: Patients from the Groningen Leeuwarden AS cohort receiving bisphosphonates based on clinical indication and available 2-year follow-up BMD measurements were included. BMD of lumbar spine (L1–L4) and hip (total proximal femur) were measured using dual-energy X-ray absorptiometry. Spinal radiographs (Th4–L4) were scored for vertebral fractures according to the Genant method. Results: In the 20 included patients (median 52 years, 14 males), lumbar spine and hip BMD Z-scores increased significantly; median from −1.5 (interquartile range [IQR] −2.2 to 0.4) to 0.1 (IQR −1.5 to 1.0); P