Prevalence and Incidence of COVID-19 Infection in Patients With Chronic Plaque Psoriasis on Immunosuppressant Therapy

The ongoing COVID-19 pandemic has hit Northern Italy (including the Veneto region) particularly hard, causing several deaths and putting a huge strain on the Italian National Healthcare System. In the absence of specific treatments, preventing the infection from spreading remains the only effective measure. There is a lot of apprehension both from doctors (including dermatologists, rheumatologists and gastroenterologists) and their patients that immunosuppressive medications (biologics, methotrexate, ciclosporin and corticosteroids) might lead to an increased susceptibility to COVID-19 infection or negatively influence the course of the infection. However, there is currently a lack of scientific evidence to recommend whether immunosuppressive treatments should or should not be continued in patients who have no symptoms of COVID-19 infection. Besides, treatment discontinuation would cause flare-ups of diseases - such as plaque psoriasis, psoriatic arthritis and inflammatory bowel diseases - which are invalidating and have a relatively high prevalence in the Veneto population. In the Unit of Dermatology of the Azienda Ospedaliera Universitaria Intergrata di Verona alone, more than 2000 patients are currently being treated with immunosuppressive agents. As of now, there are no data available on the prevalence and incidence of COVID-19 infection in patients with immune-mediated diseases, nor can data from randomized clinical trials be extrapolated to the susceptibility to COVID-19 infection in patients on biologic drugs. This study aims to assess the prevalence and incidence of COVID-19 infection in patients with chronic plaque psoriasis on immunosuppressive therapy and to identify associated risk factors. Such data would prove invaluable for clinicians dealing with patients on immunosuppressive agents during the coronavirus outbreak.