Bone mineral density in mild and advanced ankylosing spondylitis

Area of Science:

• Rheumatology
• Orthopedics
• Endocrinology

Background:

• Ankylosing spondylitis (AS) is a chronic inflammatory disease primarily affecting the axial skeleton.
• Bone mineral density (BMD) assessment is crucial for managing AS patients due to increased fracture risk.

Purpose of the Study:

• To compare BMD and determine osteoporosis frequency in mild versus advanced ankylosing spondylitis.
• To evaluate the utility of lumbar spine and hip dual-energy X-ray absorptiometry (DXA) in assessing osteoporosis in AS.

Main Methods:

• Seventy-three AS patients were categorized into mild and advanced groups using BASRI scores.
• BMD was measured at the lumbar spine and hip via DXA.
• WHO criteria were used for diagnosing normal bone density, osteopenia, or osteoporosis.

Main Results:

• Overall, 61.6% of AS patients had osteopenia or osteoporosis in the lumbar spine and 46.6% in the total hip.
• Advanced AS patients showed significantly higher rates of osteopenia/osteoporosis at the total hip (75%) compared to mild AS patients (42.3%).
• Lumbar spine BMD showed no significant difference between mild and advanced AS groups, potentially due to syndesmophytes and calcification.

Conclusions:

• Osteoporosis is prevalent in both mild and advanced AS.
• Hip DXA is more sensitive than lumbar spine DXA for detecting osteoporosis in advanced AS.
• Lumbar spine DXA results may be confounded by AS-related spinal changes, making hip assessment more reliable.