Comparison of the Simple Patient-Centric Atopic Dermatitis Scoring System PEST with SCORAD in Young Children Using a Ceramide Dominant Therapeutic Moisturizer

Atopic dermatitis (AD) is a chronic, relapsing inflammatory skin disorder with onset commonly occurring in infancy and childhood [1‐3]. AD-prone patients may develop allergic rhinitis, food allergy and asthma [1, 4‐6]. AD arises as a result of a complex interaction of environmental and genetic factors. Breakdown of the skin barrier is common to all forms of AD. At the mild end of the severity spectrum, this predominantly arises as a result of outside-inside interactions, while at the severe end of the spectrum, it is predominantly inside-outside with immune dysregulation playing a major role [1, 7]. Meanwhile, there is increasing evidence supporting a barrier-initiated pathogenesis of AD [7‐10].

The severity of AD can be assessed using various scoring systems such as the scoring of atopic dermatitis index (SCORAD), eczema area and severity index (EASI) and patient-oriented eczema measure (POEM), each of which is sensitive and widely accepted [11‐14]. SCORAD was developed by the European Task Force on Atopic Dermatitis (ETFAD) [15] to assess the extent and severity of AD. Considered an objective measure, SCORAD’s strengths include its validity, responsiveness and inter-observer reliability. Its limitations were previously reported [13, 16, 17].

Patient eczema severity time (PEST) is a new, simple daily measure, which supports the patients’ own perception and experience of the severity of their disease [18]. Patients or carers rate the severity of AD on a daily basis, thus reflecting disease fluctuations over a period of time instead of at discrete time intervals. Such insights may promote effective management of AD.

This study sought to investigate the correlation between SCORAD and PEST scores over 12 weeks in children between 6 months and 6 years of age.

Charman and colleagues revealed that use of valid and clinically meaningful patient outcome measures is gaining importance as more stress is being placed on the results of patient/carer measures in clinical trials [19]. Clinical assessments of disease may be inadequate to express disease impact, and subjective measures may help to provide a more complete and appropriate assessment of the effect of treatment on patients’ lives [12, 20]. Mason and colleagues reported a new patient-centric scoring system, PEST for assessment of atopic dermatitis [18]. PEST is a simple system, which assesses a patient’s (or carer’s) global feeling about the severity of disease instead of clinical opinion, while its ease of use as a daily record allows important changes over time to be captured. The pictorial design helps the parents to assess the PEST score in patients who are too young to vocalize their own experience.

PEST was used concurrently with POEM in an educational programme aimed at increasing emollient use and reducing AD symptoms in 136 children aged 3 months to 6 years with mild to moderate atopic eczema [18]. The POEM scale uses a questionnaire of seven questions, each with a 5-point scale (0–4) to assess symptom frequency and the pattern of remission and relapse. Topical emollient application reduced AD severity: on average, the POEM score reduced by 5.38 (95% CI 4.36–6.41, p  =  0.001), a 47% reduction from baseline, while the PEST score reduced by 0.61 (95% CI 0.47–0.75, p  =  0.001), a 48% reduction from baseline. POEM and PEST scores were strongly correlated with Pearson correlation coefficients. At week 12, the correlation coefficient was 0.71 (p < 0.01). While POEM assesses and aggregates the frequency of signs and symptoms experienced in the past week, PEST captures changes over time of the summative experience of the patient. Thus, a major advantage of the PEST score is that it takes only a couple of seconds for the patient/carer to give a score.

In the present study, we evaluated the use of SCORAD and PEST scores in the management of AD in children aged 6 months to 6 years who used a ceramide-dominant therapeutic moisturizer. SCORAD and PEST scores were moderately correlated at week 4 (r = 0.52) and at week 12 (r = 0.51), providing some cross validation, although the two measures may be capturing different aspects of the disease. SCORAD provides detailed clinical assessments at a point in time; PEST describes and summates the time-varying patient experience of AD. Interestingly, the weak correlation at baseline could be due to a disconnect between an objective scoring (SCORAD) and patient score when there is acute flare. This phenomenon could be unique in Singapore where patients are generally demanding, resulting in them giving higher PEST scores than the corresponding SCORAD score.

Also, the proportionate scale changes suggest the discrimination provided by daily assessment may make PEST a more sensitive measure with greater proportionate use of the scale range.

In contrast, SCORAD is not used as a daily measure, but is used to characterise the area and intensity of AD with minor weight given to the patient experience. Individual patients may only use a small part of its range of scores, e.g. mild disease. Thus, the sensitivity of SCORAD is constrained by the frequency of use and area of involvement. However, in contrast to PEST, SCORAD remains useful to compare severity between patients and individual patient changes during a clinical trial.

PEST, as a patient-reported outcome measure (PROM), may have particular utility as a sensitive measure for use in the clinic or clinical trials because of its range and time characteristics. The score range expands to fit an individual patient: score 1 is the best the AD is for that individual patient; score 5 is the worst it is for that individual patient. In the time domain, PEST has the ability to capture the relapsing-remitting nature of AD as experienced by the patient (or their carer) on a daily basis and thus is important in the long-term management.

The study was designed to recruit patients with current flares; thus, topical steroid(s) were used to rapidly control the inflammation. The European Guidelines for treatment of atopic dermatitis clearly state that emollient use alone on inflamed skin is poorly tolerated and recommend treating the acute flare first [21]. Therefore, one possible limitation is that the effect of the steroid on PEST in the early days cannot be ruled out. Hence, the degree of severity improvement in the early days must be interpreted carefully.

The PEST score correlates moderately with the SCORAD score and has improved sensitivity when detecting changes in the severity of AD in an individual patient in a clinical trial or in the clinic. Measuring the PEST score daily may provide insights for better patient prognosis and concordance. The ceramide-dominant therapeutic moisturizer used within the study was safe and effective in the management of AD in young children.