Societal costs and patients' experience of health inequities before and after diagnosis of psoriatic arthritis: a Danish cohort study.

Objectives: To comprehensively study the comorbidities, healthcare and public transfer (allowance) costs in patients with psoriatic arthritis (PsA) before and after diagnosis.

Methods: Nationwide cohort study, using data from Danish registries from January 1998 through December 2014. A total of 10 525 patients with PsA and 20 777 matched general population comparator (GPC) subjects were included. Societal costs, employment status and occurrence of comorbidities in patients with PsA both before and after diagnosis were compared with GPC subjects.

Results: At baseline, patients with PsA had significantly more comorbidities, including cardiovascular disease (OR 170 95% CI 155 to 186), respiratory diseases (OR 173 95% CI 154 to 196) and infectious diseases (OR 203 95% CI 169 to 242) compared with GPC subjects. At all time points, patients with PsA had higher total healthcare and public transfer costs; they also had lower income (p<0.001) and incurred a net average increased societal cost of €10 641 per patient-year compared with GPC subjects following diagnosis. The relative risk (RR) for being on disability pension 5 years prior to PsA diagnosis was 136 (95% CI 124 to 149) compared with GPC subjects. The RR increased to 160 (95% CI 149 to 172) at the time of diagnosis and was 269 (95% CI 240 to 302) 10 years after diagnosis, where 218% of the patients with PsA received disability pension.

Conclusions: Our findings are suggestive of health inequity for patients with PsA and call for individual preventive measures and societal action.