Association of body mass index on disease activity in axial spondyloarthritis: systematic review and meta-analysis

Abstract

ObjectivesIn axial spondyloarthritis (axSpA), higher body mass index (BMI) is associated with worse outcomes including response to biologics. Further clarity is needed on whether BMI is associated with disease activity overall, independent of treatment response. We performed a systematic review and meta-analysis to assess the association between BMI and disease activity as reported by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) or Ankylosing Spondylitis Disease Activity Score (ASDAS) in axSpA.MethodsWe systematically searched for studies evaluating BMI and disease activity as the exposure and outcome of interest, respectively, in axSpA. Using random effects models, we estimated summary standardised mean differences (SMDs) and 95% CIs of BASDAI or ASDAS, comparing obese (BMI>30 kg/m2) or overweight/obese (BMI>25 kg/m2) individuals to those with normal BMI (18.5–24.9 kg/m2).ResultsTwelve studies were included in the meta-analysis. Among all studies reporting the BASDAI at baseline, the pooled SMD of the BASDAI for those with an obese or overweight/obese BMI compared to a normal BMI was 0.38 (95% CI 0.21 to 0.55, I2 =75.2%), indicating a significant association of higher BMI with higher BASDAI score. The pooled SMD of the ASDAS for those with an obese or overweight/obese BMI compared to a normal BMI was 0.40 (95% CI 0.27 to 0.54, I2=0%). Findings were robust across subgroup analyses.ConclusionThese results demonstrate an association between an overweight/obese BMI and higher disease activity in studies of axSpA. Future longitudinal studies of BMI and disease activity should assess how this association changes over time.

Increased Proportion of TH17, TH22 and TC22 Cells and Correlations to IL-22, IL-10 and Clinical Parameters in a Cohort of Patients With Ankylosing Spondylitis From Northern Sweden.

“…Lastly, BMI has been suggested to in uence AS disease activity and progression of AS related radiographic spinal alterations both by a mechanical as well as an adipose related in ammation [2,44,45]. In our study we found that this life style factor, as well as smoking ever and hsCRP, that also have been shown to correlate with AS, actually correlated negatively to the level of TC22 cells.…”

Treatment Failure in Axial Spondyloarthritis: Insights for a Standardized Definition

“…Secukinumab dose escalation is being evaluated in those patients not achieving inactive disease at week 16 according to ASDAS (NCT03350815), but the results are pending. Patients with obesity/overweight usually present higher disease activity and reduced response to TNFi, and may benefit from dose intensification, if ADAs are absent [58,59], similar to the weight-based dosing of secukinumab proposed for patients with psoriasis [60]; however, weight reduction should be always advised in all patients with obesity. Most importantly, we should also remind the patients that exercise is a cornerstone of the treatment, and it is indicated in all stages of the disease.…”

Depression and anxiety symptoms at TNF inhibitor initiation are associated with impaired treatment response in axial spondyloarthritis

“…This might be considered as an intervention administered before (rather than at) TNFi initiation, but true causal effect sizes are likely smaller. Even if more realistic effect estimates were half the size, they still remain larger and more amenable to intervention that other ‘modifiable risk factors’: smoking status does not convincingly impact treatment outcomes [ 19 ]; and BMI is associated with treatment outcomes [ 20 ] but causal effects are conceptually problematic to estimate and intervention practically difficult to implement [ 21 ]. Categorizing HADS subscores will have reduced statistical power.…”