Door: N.M.C. Pouw, Universiteit Leiden.

In het kader van een afstudeerscriptie van mw. Nadine Pouw heeft Joop Lambers mede deze studie begeleid.

Abstract

The skin has many biological functions and one of them is being a central factor in interhuman communication. The skin is, for example, responsive to a variety of emotional stimuli and it can greatly affect an individual’s body image and self-esteem. The same holds for one of the skin appendages, hair.

Alopecia areata is a common form of non-scarring hair loss with an unknown aetiology. Over the years increasing evidence has suggested a role for emotional stress in the onset and/or exacerbation of alopecia areata, and many patients believe that their condition has been caused or worsened by stressful life events. Currently, there is no agreement on this idea, and the aim of the present paper was, therefore, to investigate the literature concerning this topic in order to try to determine whether there is enough scientific evidence to state with certainty that alopecia areata can be caused and/or exacerbated by emotional stress. The possible role of stressful life events in the pathology of alopecia areata, the interconnections between the nervous system, the immune system and the skin, and the diverse functions of the neuropeptide substance P that could link emotional stress to the onset and/or exacerbation of alopecia areata are discussed and it has to be concluded that there is not enough scientific evidence to state with certainty that alopecia areata can be caused and/or exacerbated by emotional stress. The hypothesis that through the action of substance P and subsequent release of interleukin-1, emotional stress is able to cause and/or exacerbate alopecia areata in humans could not be confirmed, nor could it be refuted, due to many contradictions encountered. Therefore, extensive future research is needed. Additional experiments, in which the recommendations given in this paper have been taken into account, will hopefully provide unambiguous evidence of the role of emotional stress in alopecia areata. Despite the lack of conclusive evidence, a model is presented in which substance P-mediated stress-induced mechanisms resulting in alopecia areata are hypothesized. Finally, a possible future experiment, investigating the role of substance P and its neurokinin-1 receptor in stress-induced alopecia areata through the use of a substance P receptor antagonist, is described.