Cohort profile: the clinical ‘Psoriasis in Adolescents’ (PIA) cohort in Denmark

Abstract

PurposePsoriasis is a chronic inflammatory skin disease that frequently debuts in childhood and adolescence. We wished to determine environmental and genetic risk factors for the development of psoriasis in children and adolescents, as well as to investigate debut type, trigger factors, course of disease, nature and influence of stress related to both child and family and risk factors for comorbidity. The ‘Psoriasis in Adolescents’ (PIA) cohort will provide data on the relationship between psoriasis and, respectively, genetic disposition, early-life exposures, quality of life and comorbidity.ParticipantsThe PIA cohort is nested in the large general population Danish National Birth Cohort (DNBC). We invited 390 adolescents with psoriasis and corresponding maternally predisposed and non-predisposed controls. Participants underwent an interview and a clinical examination consisting of a skin inspection and physical measurements including blood sampling and microbiological swabs. Additionally, four self-administered questionnaires on physical and mental health were completed.Findings to dateThe final PIA cohort consists of 81 adolescents with psoriasis, 110 parentally predisposed and 124 non-predisposed psoriasis-free adolescents. The validity of the maternally reported psoriasis status from the DNBC was found to be low on clinical examination (47.5%). In contrast, the self-reported psoriasis status of the DNBC mothers was clinically confirmed in 80.8% of the cases.Future plansThe PIA cohort offers the possibility of assessing the clinical characteristics, course of psoriasis and development of comorbidities in adolescents with clinically confirmed disease from a general population. Comparison with predisposed and non-predisposed controls is possible and genetic analyses are scheduled. We plan to invite the participants for a follow-up in 5–10 years. Furthermore, we plan to include newly diagnosed adolescents with psoriasis from the 18-year DNBC follow-up. All information is linkable on the individual level with data from the DNBC and nationwide registries in Denmark.

Development and preliminary validation of the Adolescent Psoriasis Quality of Life instrument: a disease‐specific measure of quality of life in adolescents with psoriasis

“… IQR, interquartile range; PASI, Psoriasis Area Severity Index, range 0–72; saSPI‐s, self‐assessed Simplified Psoriasis Index (severity subscale), range 0–50; CAM, complementary and alternative medicine. a Concept elicitation interviews (phase 1; n = 18); b cognitive interviews (phase 3; n = 12); c initial validation (phase 4; n = 50); d test–retest sample (phase 5; n = 23); e see the article by Blegvad et al …”

“…Eligible participants were patients who were aged 12–17 years, had been diagnosed with psoriasis and were able to understand and read Danish. In order for the study to achieve maximum variation in participant demographic and clinical characteristics, participants were recruited from several sites and sources, including two dermatology hospital clinics, the Danish Psoriasis Association (via the summer school, e‐mails to members, and social media), and the Psoriasis in Adolescents cohort . Recruitment sources and demographic details of each sample of patients in the study are shown in Table .…”

Presence of streptococci and frequent tonsillitis among adolescents with psoriasis

“…In a smaller clinical subsample of the DNBC – the Psoriasis in Adolescents (PIA) cohort 6 – we were able to investigate tonsillar and perineal carriage of various streptococci. The PIA cohort is a clinical case–control population nested in the DNBC and consisting of 315 adolescents (see Blegvad et al .…”

“…In a study from the Danish National Birth Cohort (DNBC), we found that tonsillitis, especially streptococcal and recurrent tonsillitis, may play a role in paediatric psoriasis. 5 In a smaller clinical subsample of the DNBCthe Psoriasis in Adolescents (PIA) cohort 6 we were able to investigate tonsillar and perineal carriage of various streptococci. The PIA cohort is a clinical case-control population nested in the DNBC and consisting of 315 adolescents (see Blegvad et al for further information).…”

The Risk of Systemic Diseases in Those with Psoriasis and Psoriatic Arthritis: From Mechanisms to Clinic

“…Patients with psoriasis have been reported to have a higher frequency of having autoimmune diseases than healthy controls [ 108 , 109 ]. In a Danish population, children and adolescents with psoriasis showed increased risks of having autoimmune disorders, including rheumatoid arthritis (OR: 6.61; 95% CI: 2.75–15.87) and vitiligo (OR: 4.76; 95% CI: 1.71–13.20), than healthy controls [ 110 ]. Table 5 summarizes the recently reported studies identifying the risk of autoimmune disorders in patients with psoriasis and PsA.…”