Crystallise Ltd., East Tilbury, UK
METHODS: We searched the heoro.com database (www.heoro.com) for abstracts reporting indirect costs in psoriasis or psoriatic arthritis published between 1960 and 1st June 2017. We analysed the abstracts identified by the search to determine the range of geographical locations, disease types, interventions and study methodologies. We presented the findings as an evidence map.RESULTS: We found a total of 57 abstracts. Of these, 14 reported indirect costs, including productivity losses, from the USA, six from Germany, five each from Italy and the UK, three each from Canada and the Netherlands, and eight were reviews of the international literature. Forty-one abstracts assessed indirect costs associated with plaque psoriasis and 19 with psoriatic arthritis. Twenty nine abstracts reported on observational cost of illness studies or those with patient-reported productivity assessments, nine included indirect costs in an economic model, seven assessed indirect costs as part of a clinical trial and 12 were reviews of the literature. Interventions studied included targeted therapies, in particular adalimumab (8 abstracts), etanercept (8), ustekinumab (5)and infliximab (3), phototherapy (6), corticosteroids (4) and cyclosporine (2), although no specific treatment was cited in 28 abstracts. Two papers were published before 2000, 16 between 2000 and 2009, and 39 between 2010 and 2017.
CONCLUSIONS: As with many diseases, there is a relative lack of published data on indirect costs of psoriasis and psoriatic arthritis, and 53% of studies reporting indirect cost data were from four jurisdictions: the US, Germany, the UK and Italy.