Is there any barrier impairment in sensitive skin?: a quantitative analysis of sensitive skin by mathematical modeling of transepidermal water loss desorption curves

Background/purpose: Sensitive skin is a vague, subjective and difficult to characterize affliction. It affects a large part of the population and is accompanied with great interest by the cosmetic industry. Some studies have suggested that sensitive skin is the result of impaired barrier function, which leads to the exposure of immune system cells and sensitive nerves, resulting in marked cutaneous responses to otherwise harmless stimuli. This study aimed to investigate the cutaneous barrier integrity of individuals with sensitive skin by a novel approach: a plastic occlusion stress test followed by measurement of transepidermal water loss (TEWL) desorption curves. Methods: The study was conducted in volunteers with sensitive skin in the hands and a control group with no sensitivity complaints. A previously developed mathematical model was adjusted to the TEWL data points and two parameters were calculated: dynamic water mass and the evaporation half‐life period. Results: Statistically significant differences have been detected in the parameters obtained in the sensitive skin group, which supports the thesis that individuals with an increased skin susceptibility have impaired barrier function. Conclusion: Whereas in the studies based in basal TEWL measurements only discrete differences were reported, the dynamic approach followed in this study provided unequivocal evidence of barrier impairment. The methodology enabled a more objective characterization of sensitive skin and can potentially be applied to the diagnosis/prediction of sensitivity; as well as the efficacy assessment of cosmetic products that are specifically designed to fulfill the needs of consumers with this skin condition.