In patients with axial spondyloarthritis (axSpA), disease duration was associated with a higher risk of developing acute anterior uveitis (AAU) and inflammatory bowel disease (IBD), but not psoriasis — which possibly represents a greater cumulative inflammatory burden in AAU and IBD — according to findings from 2 separate Belgian cohorts published in Arthritis & Rheumatology.
Despite recognition that extra-articular manifestations of axSpA and ankylosing spondylitis (AS) are highly prevalent, the literature offers little information regarding patient differentiation by and prognostic value of these extra-articular manifestations. This was the first analysis to examine differential associations between AAU or IBD vs psoriasis and structural disease progression in patients with axSpA or AS.
Data was collected from the (Be)GIANT (n=227) and ASPECT (n=1023) cohorts, both of which involved a combination of patients with diagnosed AS (n=928) and patients with non-radiographic axSpA (n=322). At inclusion, the presence or absence of extra-articular manifestations, psoriasis, AAU, and IBD was recorded and C-reactive protein (CRP) levels were obtained prospectively with medical records. In the (Be)GIANT and ASPECT cohorts, at inclusion, 34.4% and 39.7% of patients, respectively, had histories of prior extra-articular manifestations.
Of the 1250 participants, researchers found that both AAU and IBD were significantly associated with disease duration, while psoriasis was not. There were clear correlations per 10 years of disease duration, in terms of odds ratios (OR) and relative risks (RR), with AAU (OR, 1.5; 95% CI, 1.3-1.8; P <.001; RR, 1.3) and IBD (OR, 1.3; 95% CI, 1.0-1.6; P =.026; RR, 1.2), demonstrating risk increases of 30% and 20%, respectively. These associations persisted after adjustment for confounders using multivariate analysis.
In a further evaluation of a subset of 171 newly diagnosed patients followed prospectively from presentation, investigators recorded higher mean levels of CRP over time (P =.01) in the AAU and IBD groups (n=47) compared with participants with psoriasis or no extra-articular manifestations (n=124). This finding suggested that individuals presenting with AAU or IBD, but not psoriasis, might experience higher cumulative systemic inflammation exposure across time.
Study limitations included the different designs of the ASPECT (cross-sectional) and (Be)GIANT (prospective) cohorts and the lack of CRP baseline information in the ASPECT cohort.
The authors observed that “a striking association between AAU, IBD and disease duration in AxSpA was found. Surprisingly, this was not the case for psoriasis.” This may represent an increased cumulative inflammatory burden experienced by patients with IBD or AAU compared with patients with psoriasis. Regarding the potential predictive and prognostic values of their results, they noted, “as these [extra-articular manifestations] frequently seem to occur early, and prior to diagnosis, they may be an early indication of risk for progressive disease.”
Disclosures: The ASPECT cohort was collected and funded by MSD. An unrestricted grant was provided by Abbvie for the (Be)Giant cohort.
Dr Elewaut is supported by a fund of Scientific Research–Flanders (FWO) and the Research Council of Ghent University. Dr Elewaut is also a member of a multidisciplinary research platform (MRP) of Ghent University and is supported by Interuniversity Attraction Pole (IUAP) grant Devrepair from the Belspo Agency (project P7/07). Dr Elewaut has received grants or speakers fees from Boehringer Ingelheim, Pfizer, UCB, Merck, Novartis, Janssen and Abbvie. FVdB received consultancy and/or speaker fees from Abbvie, Celgene, Janssen, Merck, Novartis, Pfizer, and UCB.
Reference
Varkas G, Vastesaeger N, Cypers H, et al. Inflammatory bowel disease and acute anterior uveitis, but not psoriasis are associated with disease duration in Axial SpA: results from the (Be)Giant and ASPECT cohort [published online May 9, 2018]. Arthritis Rheumatol. doi:10.1002/art.40551