Background Several factors have been associated with the structural severity of axial SpA: older age, disease duration, HLA-B27 positivity, elevated C-reactive protein (CRP) levels, male gender and cigarette smoking status.
Objectives This study aimed to depict the characteristics of the patients with severe axial involvement in 2016 in France, after a long disease duration, and their exposition to NSAIDs, and biologics during the course of their disease.
Methods Patients with severe axial involvement were defined by the presence of at least one of the following criteria: two intervertebral adjacent bridges and/or fusion at lumbar spine and/or at cervical spine; three inter-vertebral adjacent bridges and/or fusion at thoracic spine. Patients have been identified through a nationwide effort involving 19 departments of rheumatology located in France and in Monaco (the ACTSPA network). Data have been retrospectively collected through a structured questionnaire.
Results In the current study, 133 patients have been included between February 2015 and January 2016. Mean (±SD) age was 54 yrs ± 13 at inclusion and 32 years (±12.5) at diagnosis. The patients were mainly males (n=123), sex ratio male/female was 12/1. Mean duration since the diagnosis was 22 yrs (±12.6), but was 28 yrs (± 12.3) since the first axial symptoms. 73% were ever smokers, and 37% were active smokers (n=49; men 38%, women 20%). Mean BASDAI was 2.9/10 (±1.9) and mean BASFI 3.7/10 (±2.0). 42% of the patient reported chest wall pain, 75% buttock pain, 43% peripheral arthritis, 37% enthesitis, and 8% dactylitis. Most patients were HLA-B27 positive (n=96; 72%). 80% had increased CRP during the course of the disease. Anterior uveitis prevalence was 28%, of psoriasis 19%, of IBD 9.8%. 91% of the patients were exposed to NSAIDs during the course of their disease, for a mean exposure duration of 17 years (range 1- 42 yrs). Patients were exposed to biologics in 79% of cases; all of them with at least one TNF-Blocker (mean number of anti-TNF per patient 1.57; mean exposure to the treatment 7.5 yrs). 5 patients were exposed to other biologics (ustekinumab or tocilizumab)
Conclusions This crude data analysis of patients with axial structural lesions shows patients' characteristics that were previously associated with disease severity such as high HLA-B27 prevalence, sex ratio biased toward male gender and systemic inflammation. Nevertheless, these data also demonstrate the potential huge impact of tobacco on disease severity since 73% of the patients from this cohort were ever smokers compared with 36% in DESIR cohort and 52% in the French male population (1). When considering the potential role of NSAIDs or TNF-blockers, further studies are required in particular by comparing this population to other existing cohorts of SpA patients with less structural damage. Moreover, among other mechanisms, epigenetic deregulation induced by smoking should be investigated as a potential disease severity paramer.
Tabac info service, 2000.
Acknowledgement This work has been founded by The French Society of Rheumatology
Disclosure of Interest None declared