Atopic dermatitis prevention

Novel concepts of prevention and treatment of atopic dermatitis through barrier and immune manipulations with implications for the atopic march

Skin barrier abnormalities have been suggested to play an essential role in initiation of early atopic dermatitis (AD). Antigen penetration through a compromised barrier likely leads to increased innate immune responses, antigen-presenting cell stimulation, and priming of overt cutaneous disease. In a T_H2-promoting environment, T-cell/B-cell interactions occurring in regional lymph nodes lead to excessive IgE switch. Concurrent redistribution of memory T cells into the circulation not only leads to exacerbation of AD through T-cell skin infiltration but also spreads beyond the skin to initiate the atopic march, which includes food allergy, asthma, and allergic rhinitis. Possible primary interventions to prevent AD are focusing on improving skin barrier integrity, including supplementing barrier function with moisturizers. As for secondary prophylaxis in children with established AD, this can be stratified into prevention of disease exacerbations by using proactive approaches (with either topical corticosteroids or topical calcineurin inhibitors) in mild AD cases or the prevention of other atopic disorders that will probably mandate systemic immunosuppression in severe AD cases.

A Double-Blind, Randomised Study Comparing the Skin Hydration and Acceptability of Two Emollient Products in Atopic Eczema Patients with Dry Skin

Introduction

Healthcare professionals tend to recommend emollients based primarily on patient/consumer preference and cost, with cheaper options assumed to be therapeutically equivalent. The aim of this study was therefore to compare the effects on skin hydration of two emollients prescribed in the UK, Doublebase Dayleve™ gel (DELP) and a cheaper alternative, Zerobase Emollient™ cream (ZBC).

Methods

This was a single-centre, randomised, double-blind, concurrent bi-lateral (within-patient) comparison in 18 females with atopic eczema and dry skin on their lower legs. DELP gel and ZBC cream were each applied to one lower leg twice daily for 4 days and on the morning only on day 5. The efficacy of both products was assessed by hydration measurements using a Corneometer CM825 probe (Courage-Khazaka Electronic). The measurements were made three times daily on days 1 to 5. The primary efficacy variable was the area under the curve (AUC) of the change from baseline corneometer readings over the 5 days.

Results

Skin hydration using DELP gel was significantly higher than using ZBC cream (p < 0.0001). The cumulative increase in skin hydration observed for DELP gel was substantial and long lasting. In contrast, for ZBC cream, there was no significant improvement of the cumulative skin hydration as measured by the AUC (p = 0.22).

Conclusion

DELP gel achieved substantial, long-lasting and cumulative skin hydration, whilst ZBC cream achieved no measurable improvement in skin hydration compared to before treatment. Healthcare professionals should be aware that different emollients can perform differently.

Funding

Dermal Laboratories Ltd.

Trial Registration

EudraCT number:2014-001026-16.

Emollient efficacy and acceptability in the treatment of eczematous dry skin: A double-blind, randomised comparison of two UK-marketed products

Objective: The aim of this study was to compare the moisturising efficacy and acceptability of physical characteristics of two commonly prescribed emollients licenced in the UK, Doublebase Dayleve gel (DELP) and Diprobase cream (DIPC). Methods: The study was a double-blind, concurrent bi-lateral comparison in female eczema subjects with dry skin. Results: In Part 1, comparing the area under the curve (AUC) change from baseline corneometer readings over 24 h following single applications of the emollients to the volar forearms of 34 subjects, the AUC for DELP was more than three times that seen for DIPC (p < 0.0001). In Part 2, comparing the same outcome measured over 5 days of twice daily applications to the lower legs in 36 subjects, the AUC for DELP was approximately five times that for DIPC (p < 0.0001). 69% of subjects “Like Slightly” or “Like Strongly” DELP compared to 33% for DIPC (p = 0.025). 72% indicated they would use DELP again compared to 33% for DIPC (p = 0.033). 75% of subjects preferred DELP, 17% preferred DIPC and 8% expressed no preference (p = 0.0004).

Objective and subjective in vivo comparison of two emollient products

Background

Few studies have directly compared the effectiveness of different emollients in vivo, and the important matter of patient preference is generally overlooked.

Methods

We report the results of an assessor-blinded, bilateral, concurrent comparison of two emollient pharmaceutical presentations, ie, Doublebase gel (DB) and Aqueous cream BP (AC), applied by 20 participants three times daily for 7 consecutive days. The primary efficacy endpoint was cumulative improvement in skin hydration measured by corneometry on days 1, 3, and 5 immediately before the first application and approximately 2 hours after the third application of the day. Secondary endpoints were investigator assessment of skin condition at these time points and participant assessment of product acceptability at the end of the study.

Results

Both products increased skin hydration, but the effect of AC was relatively modest, with morning values readily returning to pretreatment levels. Hydration levels were higher for DB gel, maintained at all time points, and showed stepwise, cumulative increases over the 7 days of use. Overall patient satisfaction scores were higher for DB gel, and especially for “consistency,” “ease of use,” and “ease of absorption into the skin.” Eighty-five percent of participants expressed a desire to use DB gel again as compared with 40% for AC.

Periostin promotes chronic allergic inflammation in response to Th2 cytokines

Allergic inflammation triggered by exposure of an allergen frequently leads to the onset of chronic inflammatory diseases such as atopic dermatitis (AD) and bronchial asthma. The mechanisms underlying chronicity in allergic inflammation remain unresolved. Periostin, a recently characterized matricellular protein, interacts with several cell surface integrin molecules, providing signals for tissue development and remodeling. Here we show that periostin is a critical mediator for the amplification and persistence of allergic inflammation using a mouse model of skin inflammation. Th2 cytokines IL-4 and IL-13 stimulated fibroblasts to produce periostin, which interacted with αv integrin, a functional periostin receptor on keratinocytes, inducing production of proinflammatory cytokines, which consequently accelerated Th2-type immune responses. Accordingly, inhibition of periostin or αv integrin prevented the development or progression of allergen-induced skin inflammation. Thus, periostin sets up a vicious circle that links Th2-type immune responses to keratinocyte activation and plays a critical role in the amplification and chronicity of allergic skin inflammation.

How should an incident case of atopic dermatitis be defined? A systematic review of primary prevention studies

BACKGROUND

Eczema prevention is now an active area of dermatologic and allergy research. Defining an incident case is therefore a prerequisite for such a study.

OBJECTIVE

We sought to examine how an incident case of atopic dermatitis was defined in previous atopic dermatitis prevention studies in order to make recommendations on a standard definition of new atopic dermatitis cases for use in future prevention trials.

METHODS

We conducted a systematic review of controlled interventional atopic dermatitis prevention studies by using searches of MEDLINE and Cochrane databases for studies published from 1980 to the end of January 2011. Studies that included atopic dermatitis as a secondary outcome, such as asthma prevention trials, were included.

RESULTS

One hundred two studies were included in the final analysis, of which 27 (26.5%) did not describe any criteria for defining an incident case of atopic dermatitis. Of the remaining 75 studies with reported disease criteria, the Hanifin-Rajka criteria were the most commonly used (28 studies). A disease definition unique to that particular study (21 studies) was the second most commonly used disease definition, although the sources for such novel definitions were not cited.

CONCLUSIONS

The results from this systematic review highlight the need for improved reporting and standardization of the definition used for an incident case in atopic dermatitis prevention studies. Most prevention studies have used disease definitions such as the Hanifin-Rajka criteria that include disease chronicity. While acceptable for cumulative incidence outcomes, inclusion of disease chronicity precludes the precise measurement of disease onset. We propose a definition based on existing scientific studies that could be used in future prospective studies.

A pilot study of emollient therapy for the primary prevention of atopic dermatitis

BACKGROUND

Prevention strategies in atopic dermatitis (AD) using allergen avoidance have not been consistently effective. New research reveals the importance of the skin barrier in the development of AD and possibly food allergy and asthma. Correcting skin barrier defects from birth may prevent AD onset or moderate disease severity.

OBJECTIVE

We sought to determine the feasibility of skin barrier protection as a novel AD prevention strategy.

METHODS

We enrolled 22 neonates at high risk for developing AD in a feasibility pilot study using emollient therapy from birth.

RESULTS

No intervention-related adverse events occurred in our cohort followed up for a mean time of 547 days. Of the 20 subjects who remained in the study, 3 (15.0%) developed AD, suggesting a protective effect when compared with historical controls. Skin barrier measurements remained within ranges seen in normal-appearing skin.

LIMITATIONS

No conclusions regarding efficacy can be made without a control group.

CONCLUSIONS

Skin barrier repair from birth represents a novel and feasible approach to AD prevention. Further studies are warranted to determine the efficacy of this approach.

The socioeconomic impact of atopic dermatitis in the United States: a systematic review

The aim of this study was to review studies examining the direct and indirect costs of atopic dermatitis in the United States. A search was performed using OVID MEDLINE, MEDLINE In-Process and Other Non-Indexed Citations, EMBASE, the International Agency for Health Technology Assessment (INAHTA) database, and the Cochrane Library. All abstracts were reviewed for the following criteria: original cost data, studies performed in the United States, and English language. The search yielded 418 papers. Fifty-nine papers were reviewed in detail, and four studies were found that met the inclusion criteria. These cost-identification analyses estimated the cost of atopic dermatitis heterogeneously and could not be compared directly. National cost estimates ranged widely, from $364 million to $3.8 billion US dollars per year. The cost of atopic dermatitis is significant and will likely increase in proportion to increasing disease prevalence. Measurement of the cost of atopic dermatitis in the United States has been limited to direct cost-identification analyses, with few studies measuring the indirect cost of disease.

Atopic dermatitis

Atopic dermatitis is an especially common and frustrating condition, and the prevalence is increasing. The disease can adversely affect the quality of life of patients and caregivers. Significant advances in our understanding of the pathogenesis have led to improvements in therapy. Patient and caregiver education, avoidance of potential triggering factors, optimal skin care, and pharmacotherapy offer the potential for good control for most patients.