Psychological Stress and Skin Disease

Many mental health disorders and states, such as obsessive-compulsive disorder, anxiety, stress and other psychological conditions may cause skin disease because of the nature of the skin being an easily available target for patient with such susceptible situation. It is also readily apparent that, the other way around, skin diseases may cause psychosocial distress because of their unfavorable cosmetic and/or symptomatic effects. What has been cloudy is the etiologic role of psychological stress in the start and worsening of skin disease. The probability of a causal impact of emotional stress, chiefly of stressful life events, on the course of a variety of skin diseases has long been postulated. Clinical knowledge and experience, as well as number of observations and uncontrolled case series, support this claim. In this essay, I will be reviewing the available evidence on the role of stressful life events in triggering or exacerbating skin diseases. The role of stressful life events in vitiligo, lichen planus, acne, pemphigus and seborrhoeic dermatitis was either poorly explored or controversial. The role of stressful life events in psoriasis, alopecia areata, atopic dermatitis and urticaria was evidently clearer. A few studies put into consideration common potential confounding factors (e.g. age, duration of illness, genetic factors), and almost no study considered adequately the influence of other critical factors (e.g. discontinuation of treatment, smoking, seasonal effects). Up until now, it is safe to say that only preliminary evidence has been published on the role of stressful life events in initiating or worsening any dermatological disease.

The skin plays a cardinal job as a tactile organ in socialization processes from early infancy and through the whole life cycle, having focal significance as an organ of communication, being affected to an assortment of emotional stimuli and significantly influencing a person's self-perception and confidence. It is very important to mention that the skin and the central nervous system are embryologically related, since the epidermis and the neural plate both derive from the embryonic ectoderm1.

It isn't surprising then that the presence of a connection between mental state and dermatological disease has for quite some time been seen and portrayed. A few possible connections between mental status or mental conditions and skin diseases have been proposed. To begin with, patients with a diagnosed psychological disease may come to the attention of the dermatologist because of hypochondria, self-mutilation or skin-related delusions. Second, systemic diseases, such as systemic lupus erythematosus or porphyria, might present both by skin diseases and mental side effects. Third, drugs used to treat dermatological diseases (e.g. corticosteroids, antihistamines) may actuate mental aggravations, and, then again, psycho-tropic medications, for example, lithium or a few antipsychotics may influence the skin.

Fourth, psychological side effects may show up in patients with primary skin diseases in response to reaction to disfigurement or perceived social stigma2.

In this essay, I will be reviewing the available evidence on the role of stressful life events in relation to triggering or exacerbating skin diseases. I will try to give an answer to the following question: What is, if there is, relation between psychological condition and skin diseases? Even though the association seems almost clear, and is often taken for granted, it is a very difficult task to explain the relation between these two broad entities, since research data are systematically reviewed or subjected to meta-analysis.

This complex, chronic skin disease has gotten the most consideration from a psychological perspective. More than one century there has been much hypothetical writing on the connection between psychological stress and psoriasis, and the trend continues up until now. It has turned out to be invoke psychological stress as a causative factor in psoriasis, by dermatologists as well as by patients. In a sample of 62 French dermatologists who answered to a small questionnaire, 100% concurred that stress has an essential impact in psoriasis3. Similarly, the extent of patients who think that psychological stress is an independent factor of causation or goes about as an intensifying element in psoriasis is very high, with studies reporting ranges from 37 to 78%4.Numerous uncontrolled investigations support the thesis that emotional stress, most commonly in the form of stressful life events, plays a big role in initiating or exacerbating psoriasis in elevated percentages of cases. Susskind and McGuire found that 40% of 20 in-patients mentioned anxiety and unexpressed resentment induced by upsetting life events before onset of disease; with relapses the percentage increased to 70%5. Likewise, de la Brassinne and Nays reviewed the clinical records of more than 200 patients and reported that an important psycho- logical event was a precipitating factor in 40% of new cases and in 80% of relapses6. In summary, a greater part of the reviewed studies implicate a role of stressful life events in initiating, exacerbating or worsening psoriasis. Nevertheless, conclusive evidence still does not seem to exist because widely accepted methodological standards of life event research were met by only a small number of studies and no study controlled for the influence of possible confounding factors such as discontinuation of medical treatment, use of alcohol, smoking, exposure to sun- light or seasonal effects, as noted earlier. One can oy conclude that preliminary evidence has been gathered for now and that further research is required.

Atopic dermatitis (AD) is a chronic inflammatory skin disease associated with cutaneous hyperreactivity to environmental triggers, and is often the first step in the atopic march resulting in asthma and allergic rhinitis [1]. Clinically, AD is characterized by pruritic, eczematous, ill- defined, and erythematous patches with a predilection for skin flexures. Typically, AD presents in infancy and early childhood; 85% of affected children show symptoms before age 5 years [2]. With an estimated prevalence of 17% in US schoolchildren, AD is the most common childhood chronic disease; its prevalence seems to be increasing [3].

The cause of AD is poorly understood, but is thought to involve a complex interaction of genetic predisposi- tion, environment, altered immunologic function, and psychologic influences. New insights into its etiologinclude filaggrin and Toll-like receptor 2 (TLR2) muta- tions. Filaggrin is involved in the cornified cell envelope in epidermal cells and is critical for maintaining epidermal barrier function. TLR2 is involved in the innate immune system’s ability to recognize and alert to the presence of external pathogens. New gene and chromosomal candi- dates include chromosome 1q21 (holds the gene encoding filaggrin); serine protease inhibitor Kazal-type 5 (SPINK5, a protease inhibitor); signal transducer and activator of transcription 6 (STAT-6, a transcription factor important in interleukin [IL]-4 and IL-13 signaling); regulated on activation, normal T-cell expressed and secreted (RAN- TES, a chemokine important for eosinophil recruitment and activation); and receptors for IL-4 and IL-13 [4].

AD can profoundly affect many aspects of a child’s life. Studies using quality-of-life measures demonstrated that children with AD suffer more impairment than children with other chronic diseases (eg, diabetes; cystic fibrosis) [5]. Living with a chronic skin condition can be stressful for sufferer and caregiver. Conversely, stress is thought to affect AD through various mechanisms. Psychologic stress affects neuroendocrine and immune system func- tions, and alters skin barrier function. These observations form the basis of the “psychobiologic model,” in which psychologic stress has a multifactorial effect on AD, and concomitantly AD distresses the sufferer. The psychobio- logic model was established via research into other chronic skin conditions [6]. Stress may play a significant role in the pathogenesis and course of AD skin conditions. This phenomenon is difficult to study, given AD’s childhood onset and potential for recall bias. One study suggested that up to 70% of patients with AD had experienced some emotional stress before the onset of skin disease [7]. The effect of everyday stressors was demonstrated by studies in which patients kept a diary of daily events, which was later compared with AD lesion severity [8].

Here, we discuss how stress affects AD, how AD leads to stress, and evidence for stress-reducing modalities in mitigating signs and symptoms. For practical purposes, we avoid the distinction between acute and chronic phases.