HIPPOCRATES is an Innovative Medicines Initiative (IMI) funded EU Consortium established to address key unmet clinical needs in psoriatic disease. As part of the project, the HIPPOCRATES Prospective Observational Study (HPOS) is a study of patients with psoriasis which is recruiting across Europe. The study is led by a research team at University of Oxford and supported by a team at University College Dublin. This current study aims to identify people with psoriasis who are at risk of developing psoriatic arthritis. Up to one-third of patients with psoriasis will develop a related arthritis causing inflammation in the joints and tendons. The investigators want to identify which patients will develop arthritis with the long-term and ambitious aim of trying to prevent the development of arthritis before it occurs. The HPOS study is currently recruiting/approaching adults with psoriasis and asking study participants to complete questionnaires every 6 months via a dedicated study website. The questionnaires include a 'screening questionnaire' to try to identify arthritis.

Adults with psoriasis but without a pre-existing diagnosis of PsA are currently being recruited via clinics, national and international patient support organisations including those under the umbrella of EUROPSO, and media campaigns. Participants are recruited across Europe in the following countries: UK, Ireland, Italy, France, Spain, Denmark, Germany, Belgium, Netherlands, Sweden, Portugal, Greece, Norway, Switzerland, Poland and Romania. The University of Oxford is the sponsor for the study across all countries, but local regulations will be followed, and local ethical approval has been sought for each different country. Data is requested from participants every 6 months and they will be prompted by email.

Likewise, the iPROLEPSIS consortium is a Horizon Europe funded consortium investigating digital biomarkers in PsA. In 2024, the consortium launched a study recruiting 600 patients with PsA across 4 counties, utilising digital biomarkers to identify disease flares. This includes the use of smartwatches, a mobile phone app and active video tests. This will allow us to develop algorithms to identify active disease.

Similar approaches are proposed for a study called the Inflammation Digital Biomarkers Study (IDBV) which will try to identify the onset of PsA in people living with psoriasis. Patients in HPOS who have given consent to be contacted about additional studies, will be offered the opportunity to join this study. They will complete an additional consent form and will download the miPROLEPSIS lite app to their mobile phone.

The Study app will passively collect data from the user's phone; participants do not need to perform any specific tasks apart from some initial configuration steps like logging in and connecting their wearables (Connecting a wearable is optional).

The investigators intend to run IDBV as a sub-study in HPOS and invite participants enrolled into the HPOS study who do not have a diagnosis of PsA.

Inclusion Criteria:

Previously consented to take part in the HPOS study and have agreed to be contacted for future ethically approved studies.

Adults with psoriasis with no diagnosis of PsA.

Have a compatible smartphone

Have a good command of local language

Exclusion Criteria:

Participants not consented into the HPOS study

Do not have use of a compatible smartphone

Are not willing to use the smartphone app.

Adults with a pre-existing diagnosis of PsA

Adults with a diagnosis of psoriasis and without psoriatic arthritis currently enrolled in the HPOS study.