A new instrument for the screening of psoriatic arthritis among psoriatic patients

The purpose of this study was to evaluate the performance of a dermatologist-filled-in 7-item questionnaire (called HERACLES) as a screening tool for psoriatic arthritis (PsA) in patients with psoriasis.

This study was performed in Italy in seven dermatology centres cooperating with rheumatology centres. Adults with psoriasis were consecutively recruited up to a calculated number of 750. They were invited to fill in the following questionnaires used for PsA screening: ToPAS, PASE, PEST, and EARP. The dermatologists, in addition to standard demographic and clinical data, scored each participant using a new 7-item questionnaire. All participants were later evaluated by the rheumatologists for a diagnosis of PsA. The performance of the various questionnaires was compared using receiver-operating-characteristic (ROC) area-under-the-curve (AUC) analysis.

Of the 759 enrolled psoriatic patients, 524 (280 males and 244 females) were suitable for data analysis. PsA was diagnosed in 73 (13.9%) participants. PsA and non-PsA patient characteristics were comparable, except for arthritis-related features which were often more prevalent in the PsA group. The ROC AUC of the HERACLES instrument was 0.775 (CI: 0.722-0.828), similar to that of the other questionnaires (ToPAS 0.757; PASE 0.730; PEST 0.741; and EARP 0.739). For the HERACLES instrument, a score value of 2 yielded a sensitivity of 92% and a specificity of 47%.

In this study, a dermatologist-filled-in questionnaire proved to be not inferior to patient-administered PsA screening tools and to be feasible. It might be an alternative (or additional) tool to screen psoriatic patients for rheumatology referral.