The Hidden Struggle: Understanding the Psychosocial Impact of Dermatological Diseases

Nosogenic comorbidities

Nosogenic comorbidity, the complex relationship between psychiatric disorders and dermatological diseases, manifests through two distinct types: Hypochondriacal nosogenesis and dysmorphic nosogenesis^[18] [Table 2].

Individuals with dysmorphic nosogenies tend to focus on perceived flaws, impacting their mental well-being. The clinical expression of nosogeny is further shaped by factors such as skin condition severity, premorbid personality structure, somatoperceptive accentuation and the presence of comorbid mental disorders. This intricate interplay may result in paradoxical dissociation of quality of life from dermatosis severity, accompanied by amplification and somatisation of itching.

Somatisation

Medically unexplained dermatologic symptoms such as pruritus, numbness and burning are collectively identified as somatisation. This phenomenon can occur independently or coexist with dermatological diseases, warranting attention when patients excessively worry about their skin and invest substantial time and energy in its care. Notably, certain skin disorders, such as pruritus, may represent a manifestation of somatisation, while others such as atopic dermatitis (AD) and psoriasis may predispose individuals to somatic symptoms.^[19]

The aetiology of somatic symptoms and related illnesses is multifaceted, involving genetic and environmental factors.^[20] Increased pain sensitivity, childhood trauma and cultural norms that stigmatise psychological suffering contribute to this intricate web.^[21,22] Individuals lacking psychological insight may experience overwhelming consequences of trauma, with emotional symptoms manifesting as somatic complaints directed at the skin. Cultural nuances play a significant role, with somatisation being a global phenomenon but presenting with variations shaped by different cultures. Genetic factors influence the predisposition to chronic pain, though specific genes linked to somatisation remain elusive. Exploring epigenetic mechanisms becomes crucial in understanding how exposure to psychological trauma can lead to the subsequent development of cutaneous somatisation.^[23]

Neuroimmune dynamics

There is a strong commerce between the immunological and nervous system in the skin. This relationship is delved by psychoneuroimmunology and can be divided into three different types: (1) Psychophysiological disorders; (2) primitive psychiatric disorders and (3) secondary psychiatric disorders.^[24,25] Secondary psychiatric disorders, such as reactive depression, anxiety, social isolation and suicidal ideation, significantly impact patients’ quality of life, particularly in conditions such as psoriasis, hidradenitis suppurativa (HS) and AD.

Anxiety disorders are indicative of hyperactivity in the hypothalamic-pituitary-adrenal axis. Chronic hyperactivation of this axis induces alterations in cortisol secretion, mast cell and eosinophil activation and type 2 T helper (Th2)-type inflammation. The neuro-inflammatory hypothesis provides insight into the association, with excess pro-inflammatory cytokines impacting neurotrophic support, glutamate uptake/release and cytotoxicity, resembling neuropathological findings in depressive disorders.^[26]

The shared embryological origin and release of common neuromodulators and biochemical systems between the skin and the central nervous system underline the profound reactivity of the skin to psychiatric and psychological conditions. This interaction plays a significant role in the pathogenesis of various skin diseases, potentially leading to psychological challenges such as depression, frustration and social phobias, particularly in cases of disfiguring skin disorders.

Role of stress

Stress is a known detector for a variety of psychodermatological conditions. The underpinning mechanisms include overexpression of the corticotropin-releasing hormone system, activation of inflammatory and immunological processes and neuropeptide action. Acute stress effects^[1,27] are described in Table 3.

Immunological dynamics

Recent studies unveil the role of Th1, Th2 and Th17 cells, along with keratinocytes and mast cells, in triggering interleukin (IL)-24 production – a pivotal cytokine in allergic and autoimmune diseases. The cascade of events includes the activation of classic pro-inflammatory cytokines such as IL-1, IL-6 and TNF-alpha, impacting the hypothalamus-pituitary-adrenal axis. This axis, recognised as a central pathway linking psychological stress to cutaneous inflammation, involves the release of corticotropin-releasing hormone, adrenocorticotropic hormone and corticosteroids.^[28] Through the interconnected roles of mast cells and T cells, a deeper understanding emerges of the pathways through which primary dermatoses contribute to the development of psychiatric comorbidities, highlighting the intricate interplay between immunological and psychiatric dimensions in dermatological pathophysiology.

Psychoanalytics

Developmental psychology suggests that an early tactile phase significantly influences the formation of an individual’s identity. Dermatoses may be linked to early attachment issues, especially during the development of childhood cognition when confronted with a genetic dermatosis. The process of self-development includes a ‘psychoanalytical dialogue with the skin.’^[1] Some dermatoses, such as port-wine stains and hairy nevi existing before identity formation, generally do not pose psychosocial challenges as individuals can integrate these features into their body image/identity. However, skin lesions appearing later, like scars or vitiligo, tend to contribute to body image disorders. In cases like AD, conflicts in psychological closeness-distance dynamics can be influential. There is a theory suggesting that a mother’s excessive attention to a child with uncontrollable pruritus might lead to fatigue and, potentially, subtle aggression due to uncertainty about the progression of dermatoses. In addition, increased care and attention during itching/scratching could reinforce the child’s behaviour.

Psychoneuroendocrine immunology

The gut and skin are integral components of neuroendocrine and immune organs, where cytokines, neurohormones, neuropeptides and other messengers play roles in cellular signalling within the gut–brain–skin axis.^[1] A reduction in gut lactobacilli and bifidobacteria is associated with mental illness, and psychological stress can lead to gut barrier dysfunction through glucocorticoids, subsequently impacting the microbiome and increasing uptake of pro-inflammatory mediators. Mast cells, pivotal in psychodermatologic disorders, play a role in this process.

Both skin and intestinal mucosa secrete neuropeptides, neurohormones, hormones (endocrine) and cytokines (immune), establishing connections with other body organs and systems. This leads to a state of physiological inflammation in both skin and intestine due to constant exposure to microorganisms and antigenic charge. Epithelial barrier disruptions, altered immune balance and homeostatic disruption can initiate low-grade chronic inflammation, contributing to disease onset.

Dermatoses such as AD, vitiligo and acne vulgaris are linked to skin microbial changes and loss of physiological immunocompetence. Following the psychoneuroendocrine immunologic concept, an innovative approach involving low-dose cytokine therapy has been introduced to address cutaneous inflammatory diseases.

The association between dermatoses and psychiatric disorders can be astronomically understood in two ways: Dermatoses leading to stigma, social withdrawal and body image disturbances, causing psychological disorders and psychological stress leading to systemic inflammation resulting in dermatoses and psychiatric disorders like depression.

In summary, psychological comorbidities commonly associated with inflammatory dermatoses can present in various forms: psychiatric behaviours leading to skin lesions, dermatoses causing psychological distress, shared inflammatory pathways contributing to both dermatoses and psychological disorders, as well as cases where purely psychiatric conditions manifest with skin symptoms.

Multiple choice questions

1. What concept was coined by psychoanalyst Didier Anzieu to describe the psychological representation of the ego in relation to the skin?

   1. Psychoimmunology

   2. Psychoneuroendocrinology

   3. Psychodermatology

   4. Skin ego

   Answer Key: d

2. Which of the following is NOT considered one of the primary psychopathologies focused on the skin in psychodermatology?

   1. Psoriasis

   2. Eczema

   3. Acne

   4. Bipolar disorder

   Answer Key: d

3. What percentage of dermatology patients have psychiatric and psychosocial comorbidities?

   1. 10%

   2. 20%

   3. 30%

   4. 40%

   Answer Key: c

4. What term describes medically unexplained dermatologic symptoms such as pruritus, numbness and burning?

   1. Psychosomatic symptoms

   2. Somatisation

   3. Hypochondria

   4. Dysmorphia

   Answer Key: b

5. Which of the following skin disorder is NOT linked to psychological suffering according to the text?

   1. Psoriasis

   2. Acne

   3. Atopic dermatitis

   4. Port wine stains

   Answer Key: d

6. What is the term used to describe the association between dermatoses and psychiatric disorders resulting in stigma, social withdrawal and body image disturbances?

   1. Psychogenic reaction

   2. Psychosomatic disorder

   3. Psychoneuroendocrine disorder

   4. Nosogenic comorbidity

   Answer Key: d

7. Which neurohormone is mentioned in the text as being indicative of anxiety disorders?

   1. Serotonin

   2. Dopamine

   3. Cortisol

   4. Melatonin

   Answer Key: c

8. What role does stress play in the development of psychodermatological conditions?

   1. Stress decreases inflammatory processes

   2. Stress has no impact on skin conditions

   3. Stress suppresses immune function

   4. Stress promotes skin healing

   Answer Key: c

9. According to the text, what cells are involved in triggering IL-24 production, a pivotal cytokine in allergic and autoimmune diseases?

   1. B cells

   2. T cells

   3. Natural killer cells

   4. Macrophages

   Answer Key: b

10. What is the proposed solution for addressing the high risk of mental health disorders among dermatology patients?

    1. Increasing the use of corticosteroids

    2. Implementing mental health screening into routine encounters

    3. Avoiding discussions about psychological factors

    4. Focusing solely on treating skin conditions

    Answer Key: b