Korean J Intern Med.  2015 May;30(3):391-397. 10.3904/kjim.2015.30.3.391.

Predictive factors of radiographic progression in ankylosing spondylitis

• Kim H
• Lee J
• Ahn JK
• Hwang J
• Park EJ
• Jeong H
• Cha HS
• Koh EM

• KMID: 2160712
• DOI: http://doi.org/10.3904/kjim.2015.30.3.391

Abstract

BACKGROUND/AIMS
The course of ankylosing spondylitis (AS) is rather variable, and the factors that predict radiographic progression remain largely obscure. In this study, we tried to determine the clinical factors and laboratory measures that are useful in predicting the radiographic progression of patients with AS.
METHODS
In 64 consecutive patients with AS, we collected radiographic and laboratory data over 3 years. Radiographic data included images of the sacroiliac (SI) and hip joints and laboratory data included areas under the curve (AUC) of erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), alkaline phosphatase (ALP), and hemoglobin (Hb). We investigated associations among changes in radiographic scores, initial clinical manifestations and laboratory measurements.
RESULTS
Changes in scores for the SI joint and lumbar spine did not correlate with AUC for ESR, CRP, or ALP. AUC for Hb did not significantly correlate with radiographic progression in any joint. Patients with hip arthritis at the initial visit showed significantly higher radiographic score changes after 3 years in the SI and hip joint compared to those without hip arthritis. Patients who had shoulder arthritis as the initial manifestation had significantly increased AUCs for ESR and CRP compared to those without shoulder arthritis. However, at 3 years, the change of the lumbar spine score was significantly higher in patients without shoulder arthritis.
CONCLUSIONS
These results indicate that hip arthritis at presentation is a useful clinical marker for predicting the structural damage to the SI and hip joint, and suggest that initial shoulder arthritis correlates with slower radiographic progression of the lumbar spine.

Keyword

Acute-phase proteins; Inflammation; Spondylitis, ankylosing; Disease progression

MeSH Terms

Adolescent
Adult
Alkaline Phosphatase/blood
Biomarkers/blood
Blood Sedimentation
C-Reactive Protein/metabolism
Disease Progression
Female
Hemoglobins/metabolism
Hip Joint/*radiography
Humans
Male
Osteoarthritis, Hip/blood/*radiography
Predictive Value of Tests
Retrospective Studies
Risk Factors
Sacroiliac Joint/*radiography
Severity of Illness Index
Spondylitis, Ankylosing/blood/*radiography
Time Factors
Young Adult
Biomarkers
C-Reactive Protein
Hemoglobins
Alkaline Phosphatase