Background
Previous research indicates a role of adipokines in inflammation and osteogenesis. Hence adipokines might also have a pathophysiological role in inflammation and new bone formation in patients with ankylosing spondylitis (AS). The
Conclusion
Serum leptin and HMW-APN predict protection from spinal radiographic progression in patients with AS. Women generally have higher leptin and HMW-APN serum levels that might explain why they have less structural damage in the spine as compared to male patients with AS.
Methods
A total of 120 patients with definite AS who completed a 2-year follow up in the ENRADAS trial were included in the current study. Radiographic spinal progression was defined as: (1) worsening of the modified Stoke Ankylosing Spondylitis spine (mSASSS) score by ≥2 points and/or (2) new syndesmophyte formation or progression of existing syndesmophytes after 2 years. Serum levels of adipokines (adiponectin (APN) and its high molecular weight form (HMW-APN), chemerin, leptin, lipocalin-2, omentin, resistin, visfatin) were measured using enzyme-linked immunosorbent assays.
Results
There was a significant association between radiographic spinal progression and both leptin and HMW-APN. Baseline serum levels of both adipokines were lower in patients who showed radiographic spinal progression after 2 years. This association was especially evident in men; they had generally lower leptin and HMW-APN serum levels as compared to women. The inverse association between adipokines and radiographic spinal progression was confirmed in the logistic regression analysis: the odds ratios (OR) for the outcome "no mSASSS progression ≥2 points" were 1.16 (95% CI 1.03 to 1.29) and 1.17 (95% CI 0.99 to 1.38), for leptin and HMW-APN, respectively; for "no syndesmophyte formation/progression" the respective OR were 1.29 (95% CI 1.11 to 1.50) and 1.18 (95% CI 0.98 to 1.42), adjusted for the presence of syndesmophytes at baseline, C-reactive protein at baseline, sex, body mass index (BMI), non-steroidal anti-inflammatory drugs intake score over 2 years, and smoking status at baseline.
Trial registration
EudraCT: 2007-007637-39. ClinicalTrials.gov, NCT00715091 . Registered on 14 July 2008.