Objectives To examine the association between basline body mass index (BMI) and progression of radiographic damage in axial spondyloarthritis (ax-SpA) patients. We also assessed the correlation between baseline BMI and baseline radiographic damage in terms of mSASSS score and the presence of syndesmophytes.

Methods In total 657 (431[65.6%] r-axSpA and 226 nr-axSpa; 243 [37%] female and mean age of 39.9 ± 11.7 years) patients classified as axSpA according to the “Assessment of Spondyloarthritis International Society [ASAS]” criteria were included in the study. mSASSS progression was defined as at least 2 units mSASSS score increase on radiographs taken at least two years apart. An increase in mSASSS score and/or the development of new syndesmophyte was considered as radiolographic progression.

Results Age, age at diagnosis, symptoms duration and education level were significantly different between the patients with BMI<30 and BMI≥30. BASDAI, C-reactive protein and erythrocyte sedimentation rates were similar between groups. BASFI, BASMI, fasting blood glucose, triglyceride, total cholesterol, low-density lipoprotein levels and aspartate aminotransferase values measured in the same period were significantly higher in axSpA patients with BMI≥30. While baseline total and lumbar vertebrae mSASSS scores were similar between the groups, cervical mSASSS scores were significantly high in the BMI≥30 group. In our study group baseline BMI was positively correlated with radiographic progression (r=0.201; P=<0.005) and the development of new syndesmophyte (r=0.134; P=<0.05).

Conclusion The results of this study showed that BMI was associated with both basline and the progression of structural damage in axSpA patients. The effect of high BMI on structural damege may be related to mechanical factors. However, BMI was found to be associated with cervical, but not lumbar syndesmophyte at baseline. Thse findings might be the results of increase in proinflammatory cytokines such as TNF-alfa and IL-6 and the reduction of anti-inflammatory cytokines such as IL-10 and adiponectin secreted from dysfunctional adipose tissue.

REFERENCES: NIL.

Acknowledgements: NIL.

Disclosure of Interests None Declared.