Patient perspectives on treating psoriasis with classic inpatient dithranol therapy: a retrospective patient survey

Treatment persistence in paediatric and adolescent patients with psoriasis followed into young adulthood. From topical to systemic treatment: a prospective, longitudinal, observational cohort study of 448 patients

Background

Although solely topical treatment often suffices, patients with psoriasis may require more intensive treatment (phototherapy and/or systemic treatments) to control their disease. However, in paediatric, adolescent and young adult patients, little is known about persistence of topical treatment and time until switch to systemic treatment.

Objectives

To determine the median time from psoriasis onset until (i) discontinuation of solely topical agents and (ii) switch to systemic treatment, and to identify patient characteristics associated with switching to systemic treatments.

Methods

Data were extracted from the Child‐CAPTURE registry, a prospective, observational cohort of patients with paediatric‐onset psoriasis followed into young adulthood from 2008 to 2018. Data prior to inclusion in the registry were collected retrospectively. Median times were determined through Kaplan–Meier survival analyses. Cox regression analysis was used to identify patient characteristics associated with switch to systemic treatment.

Results

Of 448 patients, 62·3% stayed on solely topical treatment until data lock; 14·3% switched from topicals to phototherapy, but not to systemic treatment; and 23·4% switched to systemic treatment. The median time from psoriasis onset until discontinuation of solely topical treatment was 7·3 years, and until switch to systemics was 10·8 years. Higher Psoriasis Area and Severity Index and (Children’s) Dermatology Life Quality Index > 5 were independently associated with switching to systemic treatment.

Conclusions

In a population of paediatric and adolescent patients with mild‐to‐severe psoriasis, one‐third needed more intensive treatment than solely topical therapy to control their disease. We consider the median time until switching to systemics to be long.

What is already known about this topic?

Psoriasis in the majority of paediatric and adolescent patients can be adequately managed with solely topical treatment. However, some patients require a switch to more intensive treatment in order to control their disease.

Little is known about persistence of topical treatment and time until switch to systemic treatment.

What does this study add?

In 448 paediatric patients with mild‐to‐severe psoriasis, 62·3% persisted on solely topical treatment, 14·3% switched to phototherapy, but not to systemics, and 23·4% switched to systemic treatment at data lock (total median follow‐up 4·2 years, interquartile range 1·8–7·5).

The median time from psoriasis onset until discontinuation of solely topical treatment was 7·3 years, and until switch to systemic treatment 10·8 years.

Higher Psoriasis Area and Severity Index and (Children’s) Dermatology Life Quality Index > 5 at switch were independent characteristics associated with switching to systemic treatment.

Linked Comment: Salman. Br J Dermatol 2021; 184:387–388.

Plain language summary available online

Dithranol targets keratinocytes, their crosstalk with neutrophils and inhibits the IL-36 inflammatory loop in psoriasis

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Resolution of plaque-type psoriasis: what is left behind (and reinitiates the disease)

Psoriasis is a chronic inflammatory skin disease that involves numerous types of immune cells and cytokines resulting in an inflammatory feedback loop and hyperproliferation of the epidermis. A more detailed understanding of the underlying pathophysiology has revolutionized anti-psoriatic treatment and led to the development of various new drugs targeting key inflammatory cytokines such as IL-17A and IL-23. Successfully treated psoriatic lesions often resolve completely, leaving nothing visible to the naked eye. However, such lesions tend to recur within months at the exact same body sites. What is left behind at the cellular and molecular levels that potentially reinitiates psoriasis? Here, we elucidate the cellular and molecular “scar” and its imprints left after clinical resolution of psoriasis treated with anti-TNFα, anti-IL-17, or anti-IL-23 antibodies or phototherapy. Hidden cytokine stores and remaining tissue-resident memory T cells (TRMs) might hold the clue for disease recurrence.