The Lactic Acid Sting Test and Baseline Transepidermal Water Loss in Patients with Sensitive Skin

Kim, Jin Young; Kim, Sang Seok; Cho, Hee Jin; Park, Chun Wook; Lee, Cheol Heon

Abstract

BACKGROUND: Patients with sensitive skin are those individuals who state that their skin is more sensitive than the average person. But there is no clear-cut dermatological definition to describe, or standard method to evaluate sensitive skin.
OBJECTIVE
To elucidate the biophysical differences between sensitive and non-sensitive skins, we measured baseline transepidermal water loss (TEWL) and performed the lactic acid sting test.
METHODS
A total of 503 people responded to self-assessment questionnaires, composed of questions about self-perception, related factors, and symptoms and signs of sensitive skin. In 55 of these, we measured baseline TEWL and performed a 10% lactic acid sting test on the malar eminence of the face using a Hilltop chamber. In the lactic acid sting test, the stinging sensation was rated by patients every 1 minute, on a 4-point scale, with cumulative stinging scores.
RESULTS
The incidence of self-reported sensitive skin was 43.3% for women and 23.9% for men. The cumulative scores of the lactic acid sting test were not higher in the sensitive skin group (p>0.05). However, the onset time of the stinging sensation was faster in the sensitive skin group (p<0.05). There was no difference in the baseline TEWL (p>0.05) between the sensitive skin and non-sensitive skin groups. Furthermore there was no correlation between baseline TEWL and 10% lactic acid sting test in the sensitive skin group compared to the non-sensitive skin group (p>0.05).
CONCLUSION
Our experiment showed that the 10% lactic acid sting test is still not an adequate or ideal method to assess sensitive skin, and another new reproducible and objective method is necessary to assess sensitive skin.