Psoriasis in Norway: A Prescription-based Registry Study of Incidence and Prevalence.

Epidemiological data on psoriasis in Norway are limited. The aim of this study was to provide objective national data on the incidence and prevalence of psoriasis. Patients registered in the Norwegian Prescription Database with a diagnostic code indicating psoriasis vulgaris on prescriptions were included. During the period 2004 to 2020, 272,725 patients received prescription for psoriasis vulgaris in Norway. During the period 2015 to 2020, 84,432 patients received prescription for psoriasis vulgaris for the first time. In 2020, 71,857 (97.7%) patients received topical, 7,197 (9.8%) conventional systemic and 2,886 (3.9%) biological medication for psoriasis vulgaris. In the period 2015 to 2020, the point prevalence of psoriasis was 3.8-4.6% and the incidence was 0.29-0.25%. Norway is divided into 4 geographical health regions. A latitudinal difference was observed between the 4 regions, highest in Northern Norway. In the incidence population, median age was 47-53 years and males comprised 46-50%. In this study of psoriasis vulgaris, prevalence in Norway was higher than in earlier reports from other countries. There was a small female predominance regarding incidence and prevalence; however, men had more prescriptions for systemic treatment. Prescriptions for psoriasis vulgaris showed a stable level, with a trend of increasing use of biological medication during the study period.

Psoriasis in Norway: a prescription-based registry study of psoriasis-associated comorbidities.

Psoriasis is an inflammatory skin disease, frequently associated with comorbidities. The aim of this study was to characterize comorbidities associated with skin psoriasis using real-world data. The study was conducted in Norway, taking advantage of the universal healthcare system with equal access to healthcare and a mandatory prescription reporting system that applies to all hospitals and clinics. The study focused on patients registered in the Norwegian Prescription Database (NorPD) who had either a diagnosis code indicating skin psoriasis alone or in combination with diagnosis codes for pre-selected comorbidities. Between 2004 and 2020, a total of 272,725 patients diagnosed with skin psoriasis were identified in NorPD, and 84,432 patients received their first prescription for skin psoriasis between 2015 and 2020. Among these, patients who received prescriptions for pre-selected comorbidities, either before or after initial prescription for psoriasis treatment, were included in the study. The most common prescriptions for patients with skin psoriasis were for primary prevention of atherosclerotic disease (22.6%), established atherosclerotic disease (19.3%), and depression (18.4%). These were closely followed by prescriptions for other comorbidities such as heart failure (16.1%), type II diabetes mellitus (9.4%), hypertension (9.4%), anxiety (7.8%), psoriatic arthritis (5.5%), acute myocardial infarction (4.2%), hypertensive cardiac disease (3.0%), ulcerative colitis (2.4%), type I diabetes mellitus (2.2%), secondary prophylaxis after myocardial infarction (1.6%), and Crohn's disease (1.0%). Patients with skin psoriasis have a high number of prescriptions not only for their psoriasis but also for many other conditions compared to reports in the literature on the general population.

Biological treatment in severe psoriasis: Influence on peripheral blood dendritic cells.

In-depth immunophenotyping by flow cytometry of peripheral blood dendritic cell (DC) populations of psoriasis vulgaris without (PsO; N = 23) or with psoriatic arthritis (PsA; N = 15), before (T1) and after 12 months (T2) therapy with the anti-TNF drugs infliximab, etanercept, the anti-IL-17A secukinumab and the anti-IL12/IL-23 ustekinumab. Compared to healthy donors (N = 38), patients with PsA displayed lower frequencies of dendritic cell subsets pDC, cDC1 and cDC2, which were normalized following treatment except pDC. In contrast, patients with PsO only displayed lower frequencies of pDC which were normalized following treatment. Figure created with BioRender.com.

Mass cytometry analysis of blood immune cells from psoriasis patients on biological therapy.

Psoriasis is a chronic immune-mediated skin disease accompanied by systemic inflammation and comorbidities. We analyzed peripheral blood mononuclear cells (PBMCs) in the search for immune signatures and biomarkers related to psoriasis severity and treatment effect. Thirty-two patients with psoriasis and 10 matched healthy controls were included. PBMCs were collected before and after initiation of anti-TNF, anti-IL-17 or anti-IL-12/23 treatment and analyzed utilizing 26-parameter mass cytometry. The number of circulating Th17, Th22, Th9, and cytotoxic T cells were increased in severe psoriasis. Intracellular pp38 and pERK in T helper cells were associated with disease severity. Differences between responders and nonresponders regarding cell composition and intracellular signaling were identifiable already at inclusion. Biological treatment induced memory cells, restored inhibitory PD-1 function of T cells, and reduced a potential pro-atherogenic profile in monocytes. In conclusion, these results indicate amelioration of systemic inflammation in psoriasis after biological treatment. Such broad immune profiling may enable prospective stratification of patients regarding future treatment response. Successful early intervention may lead to a healthier trajectory with favorable implications on later comorbidities.