Highlights from

American Academy of Dermatology

annual meeting 2018

San Diego 16-20 February 2018

Winter effect and preventing scarring

There is increasing evidence that acne pathophysiology may include a barrier defect. Acne medications are also often drying. An improvement of the barrier may improve acne, a fact that is often not addressed in acne therapy.

“The distinct vehicle response often seen in trials with topical medications may be due to improvement of barrier,” said Prof. Hillary Baldwin of the Acne Treatment and Research Center [1]. In to her experience, this barrier improvement is part of a successful acne management.

“Patients are happier when physicians also address the dryness of their skin,” she said. Patients with moderate-to-severe acne have a higher transepidermal water loss (TEWL) compared with control subjects [2]. An impaired water barrier function may be responsible for comedo formation, since barrier dysfunction is accompanied by hyperkeratosis of the follicular epithelium.

A current trial showed that ceramides in the stratum corneum undergo seasonal variations over the course of a year [3]. In this trial, ceramides in the stratum corneum of healthy and acne skin were assessed using ultraperformance liquid chromatography, and seasonal variation was studied over the course of a year.

Acne often worsens in winter

Acne-affected skin demonstrated overall lower levels of ceramides compared to healthy controls. However, this difference was more apparent in the winter months. Lower ceramide levels reflected an increase in TEWL in acne compared with healthy skin, which partly resolved in the summer. Certain ceramide species with 18-carbon 6-hydroxysphingosine bases were significantly reduced in acne skin, suggesting that these species may be particularly important in a healthy skin barrier. Indeed, acne patients often report a worsening of acne during winter months [3].

A poster presented during the meeting confirmed these seasonal changes in epidermal ceramides in acne patients [4]. In addition, TEWL was assessed in the course of the year. Compared to healthy skin, acne skin showed increased TEWL year-round, but this difference reached statistical significance only from December to June [4].

The microflora of the skin also differs significantly between acne patients and healthy controls [5]. This was evident in a poster presented during the meeting that analysed the microbiome from ten healthy young women and compared it to ten patients with acne vulgaris [6]. There was no difference in the actinobacteria and proteobacteria, but a relative increase in firmicutes species in acne vulgaris. Patients with a high percentage of firmicutes species had a threefold elevated risk of having acne compared to the low firmicutes group [6].

During puberty, alteration of the sebaceous lipid profile, stress, irritation, cosmetics and potential dietary factors lead to inflammation and formation of different types of acne lesions. Skin barrier damage also significantly increases between the ages of 6 and 13. The proliferation of P. acnes strains is another important process that triggers acne. P. acnes activates the innate immunity via the expression of proinflammatory cytokines and matrix metalloproteinases by keratinocytes, resulting in the hyperkeratinisation of the pilosebaceous unit [5].

Optimal skin health and innate immunity are maintained when the microbiome and the immune system of the skin are balanced. “Therefore, quality moisturisation is essential in our acne patients,” Prof. Baldwin recommended. By using adequate moisturisers, TEWL can be improved, ceramides normalised, and the microbiome restored. This is of particular importance because acne therapy further damages the stratum corneum.

“Many patients notice the dryness of their skin and use moisturiser, but maybe the wrong ones,” warned Prof. Baldwin. No acne visit is complete without discussion of skin care. At the moment, coconut oil is “in fashion” but, due to its comedonic effect, is not suitable for acne patients. Quality moisturisers contain ceramides or hyaluronic acid.

Early therapy prevents scarring

“Acne is not a cosmetic problem: it has to be treated effectively to prevent scarring,” said Prof. Baldwin. Studies have shown that scarring can occur with any severity of acne. Even in mild acne, more than 20% of patients will have a presence of acne scars [7].

Risk factors for developing scars is the time elapsed between acne onset and the first effective treatment: ≥3 years vs. <3 years [8]. A trial presented recently confirmed the positive effect that effective treatment has on acne scar formation.

In this split-face study conducted over six months, patients were either treated with the combination of adapalen 0.1%/benzoyl peroxide (BPO) 2.5% gel or a vehicle. All participants had at least ten atrophic scars at baseline [9]. After six months of treatment, scar counts remained stable with adapalen/BPO while they increased by approximately 25% with vehicle. The percentage of subjects with barely-visible scars increased from 9.7% to 45.2% with adapalen/BPO, whereas it did not change with vehicle (p=0.0032) [9].

  1. Baldwin, H. oral presentation session S048, AAD Annual Meeting, February 16–20 2018.
  2. Yamamato. et al. Arch Derm Res 287:214–8 1995.
  3. Pappas, A. et al. Exp Dermatol 2018 Jan 21.
  4. Pappas, A. et al. P7254, AAD Annual Meeting, February 16–20 2018.
  5. Dréno, B. J Eur Dermatol Venereol 2017;Suppl5:8–12.
  6. Hitosugi, N. P6225, AAD Annual Meeting, February 16–20 2018.
  7. Tan, J. et al. J Cutan Med Surg 2010:14:156–60.
  8. Layton. Am. Clin Exp Dermatol 1994;19:303–8.
  9. Dreno, B. et al. J Eur Acad Dermatol Venereol 2017;31:737–42.

The content and interpretation of these conference highlights are the views and comments of the speakers/authors.