THU0284 Haq in psoriatic arthritis is driven by gender, inflammation and ageing: observational data from cohort studies in uk, denmark, iceland and sweden
Authors: L.E. Kristensen, T.S. Jørgensen, L.C. Coates, P. Frederiksen, B. Gudbjornsson, J.K. Wallman, N. McHugh, M.C. Kapetanovic, L. Dreyer, W. Tillett
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> Psoriatic arthritis (PsA) is a chronic inflammatory disorder associated with skin and joint involvement, pain and impaired function. HAQ has been widely used but components contributing to HAQ and changes thereof have been sparsely studied. <h3>Objectives</h3> The objective of this multinational population-based cohort study was to investigate factors associated with longitudinal changes in HAQ in patients with PsA in independent settings. <h3>Methods</h3> Data on PsA patient characteristics, disease activity components and HAQ was obtained from the DANBIO (Denmark), ICEBIO (Iceland), SSATG (southern Sweden) and BATH (UK) cohort registries. Farewell's linear increments model for missing data was used to fit each longitudinal response by regressing the observed increments onto lagged values of the response variables (HAQ, CRP and VAS pain) while also adjusting for other covariates (gender, age and disease duration). Due to homogeneity of the nature of registries, the Nordic data was pooled for patients initiating first course of biologics (anti-TNF therapy, secukinumab or ustekinumab), whereas UK data represents an ongoing cohort with different treatments. <h3>Results</h3> In the period 2006 through 2016, we identified 1473 patients from DANBIO, 168 from ICEBIO, 469 from BATH, and 716 from SSATG eligible for analyses. Mean age in years (SD) and percentage of females for the populations were 46 (SD ±12), 55% for DANBIO, 46 (SD ±12), 61% for ICEBIO, 47 (SD ±11), 51% for SSATG, and 58 (SD ±13) 49% for BATH; respectively. The figure displays observed HAQ values (solid lines) and Farewell modelled (broken lines) curves divided on gender for the development of HAQ after initiation of biologic therapy for pooled Nordic data (A) and for the ongoing UK cohort (B). It should be noted, that Farewell modelling inflates HAQ-values in the Nordic registries reflecting a correction for channelling bias due to drop out during biologic treatment. Whereas the modelled HAQ values for the BATH cohort are deflated possibly due to extra visits during flares in this ongoing observational cohort. At all time points and cohorts female HAQ values are higher than males (p&lt;0.001). After initiation of biologic therapy there is a significant decline in the HAQ scores in the Nordic registers of 0.23 (95% CI 0.21–0.25) at 6 months. Changes in CRP, VAS-pain nor disease duration did not appear to affect HAQ during follow-up. However, ageing seemed to have a tendency to increase HAQ over time. The same consistent pattern was present when analyses were done separated by country (data not shown). <h3>Conclusions</h3> In PsA, across independent European cohorts, HAQ is higher for women, and significantly decreases for both genders when anti-inflammatory treatment is initiated. HAQ does not depend on CRP, VAS-pain or disease duration during longitudinal follow-up. However, a significant increasing trend was identified with ageing. <h3>Acknowledgements</h3> This study was supported by unrestricted grants from The Oak foundation, and NordForsk. <h3>Disclosure of Interest</h3> L. E. Kristensen Speakers bureau: Pfizer, AbbVie, Amgen, UCB, Celgene, BMS, MSD, Novartis, Eli Lilly, Janssen Pharmaceuticals, T. S. Jørgensen Speakers bureau: Abbvie, Roche, UCB, Novartis, Pfizer, Biogen and Eli Lilly, L. Coates: None declared, P. Frederiksen: None declared, B. Gudbjornsson: None declared, J. Wallman Consultant for: AbbVie, Celgene, Eli Lilly, Novartis, UCB, N. McHugh Grant/research support from: Pfizer, Celgene and Abbvie, Speakers bureau: Eli Lily, Pfizer and Abbvie, M. Kapetanovic: None declared, L. Dreyer Speakers bureau: UCB, MSD, Janssen, W. Tillett Speakers bureau: Abbvie, Celgene, Eli Lilly, Janssen, Novartis, Pfizer, UCB