No difference was observed in lumbar spine aBMD in AS patients and HC (p = 0.112), but total hip BMD (p = 0.011) and TBS (p < 0.001) were lower in AS patients.
BMD (classified according to the WHO criteria for osteoporosis) of the hip and lumbar spine, the VFx (classified as a Genant score >1/>20% height loss), and radiological progression (modified stoke ankylosing spondylitis spinal score [mSASSS]) scores were obtained at baseline and at 4 years of TNFi treatment.Overall, 135 AS patients were included.
Major risk factors for vertebral fractures in patients with AS include low BMD at the femoral neck and total hip, male gender, longer disease duration, higher BASDAI, higher BASRI, and possibly inflammatory bowel disease.