PSORIASIS AND COMORBIDITIES – Psychological and Psychiatric Disorders – PART 3

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The last in our 3 part series addressing psychological and psychiatric disorders associated with psoriasis.

   Psychological and Psychiatric Disorders –

   Sleep Disorders

   Somatoform Disorders

   Substance dependence of abuse

1, 2, 3

Sleep Disorders

It is thought that psoriasis has a direct effect on the development of sleep disorders due to the cutaneous (skin) symptoms of the condition. The skin is the primary circadian mediator of core body temperature (CBT), and a decrease in CBT in the late evening is an important mechanism for sleep initiation. Psoriasis has been associated with problems with thermoregulation and researchers have indicated that the reduced ability to dissipate heat is one factor in the inability to initiate sleep. Pruritus (itch) is another contributor to sleep disturbance and it is also regulated by circadian mechanisms. The threshold for pruritus is lowered in the evening due to complex circadian-mediated factors such as lower cortisol levels, decreased epidermal barrier function, and increased distal-to-proximal (distant limbs-to-body centre) gradient in skin temperature. Thus pruritus in psoriasis typically manifests or exacerbates mainly in the evening and worsens at night. 4,5,6

 so-tired-1440121-1600x1200

The inflammatory biological mechanism(s) that lead to initiation and exacerbation of psoriasis, also contribute to the development of systemic diseases e.g. depressive disease, hypertension (blood pressure), adverse cardiac events, diabetes, metabolic syndrome and obesity. All of these conditions are known to indirectly give rise to sleep-disordered breathing. The heightened pro-inflammatory state in conditions such as obstructive sleep apnoea syndrome (OSAS) and insomnia could in turn lead to exacerbations of psoriasis.4,5,6

A systematic review of the literature on the relationship between psoriasis, PsA, and formal sleep disorders identified an increased prevalence of OSAS with a 36-81% prevalence in psoriasis versus 2% for women and 4% for men in the general population.4,5  In one study researchers found that some patients with chronic psoriasis and concurrent OSAS showed improvement of their psoriatic lesions while on nasal continuous positive airway pressure (CPAP).6 OSAS leads to severe physical and, possibly, psychological stress to the body, e.g., by hypoxemia (low blood oxygen levels), increased blood pressure, tachycardia (fast or irregular heart rate), sleep fragmentation, reduction of deep sleep, reduction of REM sleep, hypersomnia (excessive sleepiness), and insomnia. It is known that OSAS also dysregulates the function of the patient’s autonomic nervous system and hormone system. It is felt that this might alter the homeostasis of the immune neuroendocrine network in the skin and may cause the initiation of psoriasis in the genetically predisposed individuals.4,5,6

Somatoform Disorders – psychosomatic symptoms

Somatization is the manifestation of psychological distress by the presentation of bodily symptoms such as feeling nausea due to anxiety, stress headaches, falling ill after a trauma and inability to cope with a disease. 

Patients with psoriasis exhibit higher scores of hypochondriasis, hysteria, and somatization. As previously exposed hypochondriasis and hysteria may be connected with specific personality traits of patients with psoriasis of late-onset. Psychosomatic factors, namely stressful life events, lack of social support, and attachment insecurity, may explain why patients with psoriasis have greater scores of somatization. Moreover, the presence of depression in psoriasis may modulate itch perception and then exacerbate symptoms of pruritus.7 (Refer to Part 1 of this series) A systematic review of the psychosocial burden of psoriasis found that social stigmatization, high stress levels, physical limitations, depression, employment problems and other psychosocial co-morbidities experienced by patients with psoriasis are not always proportional to, or predicted by, other measurements of disease severity such as body surface area involvement or plaque severity. Some psoriasis patients had, even when their lesions were small and mild, levels of stress and loss of confidence that was not in keeping with the severity of their condition – which leads to the conclusion that they had maladaptive coping mechanisms in play e.g. self blame, blaming parents, social phobia, avoidance behaviours, substance and alcohol abuse etc. 9

Substance – Dependence of Abuse

In our previous blog Psoriasis and Alcohol (ethanol), we stated that patients with psoriasis experience considerable emotional distress, depression and social isolation due to the visibility of skin lesions, especially when the lesions are widespread and severe. Whilst it would be demeaning to state that all psoriasis patients with mild to severe psoriasis suffer from alcoholism, it has been confirmed in several Quality of Life studies that the percentage of psoriasis patients who admit to having a drinking problem may be as high as 32%. Research indicates that men are more likely to use alcohol excessively as a coping mechanism with the psychosocial burden of psoriasis. Consequently they are at a higher risk of developing depression – with the alcohol misuse and psoriasis as underlying causes. 4 Another study indicated that for women, excessive alcohol intake above a certain threshold (?30.0 g/d), may be associated with a significantly increased risk of Psoriatic Arthritis (PsA).5

have-a-drink-1-1510449-640x480-1

Alcohol is known to inhibit inflammation and immune responses; however acute and chronic alcohol consumption have opposite effects on inflammatory cell activation. Results indicate that acute alcohol exposure is inhibitory, whereas chronic alcohol exposure leads to an increase in inflammatory cell responses.6

Research has confirmed that alcoholics are more susceptible to infections, as streptococcal infections are trigger factors for psoriasis, this increased susceptibility may be involved in the onset and progress of the disease. It is also known that measurable quantities of ingested ethanol are secreted through human skin. Transdermal ethanol derives from two processes: active secretion by eccrine glands, primarily sweat glands, and passive diffusion through the lipid layers of the skin. Ethanol disrupts the dermal barrier enhancing skin permeability for numerous chemicals and increases the solubility of penetrating chemical compounds.6

Research into the the use of illicit drugs and psoriasis is extremely limited. Methylenedioxymethamphetamine (MDMA), also called Ecstasy, has been reported to initiate Guttate Psoriasis. The researchers theorized that “While MDMA [the main ingredient in ecstasy] is taken for its psychomimetic effect, pharmacologically it increases the level of noradrenaline, serotonin and dopamine by inhibiting the reuptake mechanism. It is known that Patients with psoriasis already have increased levels of noradrenaline.”7 There are also anecdotal stories on support websites where psoriasis sufferers have spoken about the exacerbation of their psoriasis with the use of “meth” (Methamphetamine, Ice). Within our clinic we have had several patients whose psoriasis was initiated and exacerbated by the use of cannabis (street not medicinal), once they ceased the use of cannabis their psoriasis resolved. As long as they did not use cannabis they remained free of any psoriatic lesions.

REFERENCES

  • Susskind W. and McGuire R.J.: The Emotional Factor in Psoriasis; Scot. med, J., 1959,4:503
  • Kessler R. C. et al.; Epidemiology of Anxiety Disorders; M.B. Stein and T. Steckler (eds.), Behavioral Neurobiology of Anxiety and Its Treatment, Current Topics in Behavioral Neurosciences 2, DOI 10.1007/7854_2009_9, # Springer?Verlag Berlin Heidelberg 2009, published online 3 September 2009
  • Nasreen S. et al.; Frequency and Magnitude of Anxiety and Depression in Patients with Psoriasis Vulgaris; Journal of the College of Physicians and Surgeons Pakistan 2008, Vol. 18 (7): 397-400
  • Brenaut E. et al.; Alcohol consumption and psoriasis: a systematic literature review. J Eur Acad Dermatol Venerol. 2013 Aug;27 Suppl 3:30-5. doi: 10.1111/jdv.12164.
  • Shaowei Wu et al.; Alcohol Intake and Risk of Incident Psoriatic Arthritis in Women; J Rheumatol. 2015 May ; 42(5): 835–840. doi:10.3899/jrheum.140808.
  • Farkas A, Kemény L.; Psoriasis and alcohol: is cutaneous ethanol one of the missing links?; • British Journal of Dermatology 2010 162, pp711–716
  • Tan B., Foley P.; Guttate psoriasis following Ecstasy ingestion; Australasian Journal of Dermatology45(3):167-9 September 2004?

PSORIASIS AND COMORBIDITIES – Psychological and Psychiatric Disorders – Part 1

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WHAT IS COMORBIDITY?

Comorbidity is a concurrence of multiple diseases or disorders in association with a given disease, in this case, psoriasis.

INCREASED RISK

 The patient with psoriasis has an increased risk of developing one or more of a number of other diseases/conditions that share many immunological features with psoriasis.

CHART 1: Comorbidities Associated with Psoriasis

Psychological and Psychiatric Disorders – Depression

anxiety

Suicide

Addiction

1, 2, 3

Psychophysiologic disorders are associated with skin conditions, such as psoriasis, that are frequently precipitated or exacerbated by emotional stress. For many sufferers of psoriasis associated depression, anxiety, addictions to alcohol etc. and even suicidal thoughts are common.

As far back as the 1940s and 1950s researchers explored the relationship between emotions and psoriasis theorizing various ideas such as “chronic psoriasis is often linked with deeply repressed emotional conflicts”, that “nervous exhaustion” may play a role in the causation and aggravation of the disease”, and that “in emotionally maladjusted individuals the psychological factor may ‘take charge’ of the psoriasis and determine its onset, persistence and relapses.” 1  

Since the 1970’s numerous studies have been conducted by researchers in the bid to understand the subtleties involved in the interplay between mental and emotional stresses, anxieties and depression with psoriasis. Research in the 2000s has greatly defined the psychological and psychiatric disorders associated with psoriasis, they include:-

Anxiety Disorders 1, 2

  • Acute stress disorder–anxiety symptoms occur immediately following a trauma, but are short-lived.
  • Adjustment disorder with anxious features–anxiety symptoms in relation to a major life-changing event – like getting married or moving to another city. Symptoms generally start within three months of the stressful event and occur for six months or less.
  • Substance-induced anxiety disorder– generally resolves when the substance is discontinued or when withdrawal from the substance is over.

INCLUDING:

  • Panic Disorder (With Or Without Agoraphobia) – consists of severe, immediate anxiety symptoms (a panic attack) due to a broad range of fears, such as of open spaces, public transportation or about being trapped or about being safe when outside the home, as well as the worry over having another panic attack.
  • Generalized anxiety disorder (GAD)– is characterized by excessive, exaggerated anxiety and worry about everyday life events with no obvious reasons for worry. People with symptoms of generalized anxiety disorder tend to always expect disaster and constantly worry about health, money, family, work, or school, which is often totally unrealistic or out of proportion for the situation. Day to day life becomes a constant state of worry, fear, and dread.
  • Social Anxiety Disorder (SAD)

       People with social anxiety disorder (sometimes called “social phobia”) have a marked fear of social or performance situations in which they expect to            feel embarrassed, judged, rejected, or fearful of offending others.

       Social anxiety disorder symptoms include:

  •   Feeling highly anxious about being with other people and having a hard time talking to them
  •   Feeling very self-conscious in front of other people and worried about feeling humiliated, embarrassed, or rejected, or fearful of                                         offending others
  •   Being very afraid that other people will judge them
  •   Worrying for days or weeks before an event where other people will be
  •   Staying away from places where there are other people
  •   Having a hard time making friends and keeping friends
  •   Blushing, sweating, or trembling around other people
  •    Feeling nauseous or sick to your stomach when other people are around
  • Obsessive-compulsive disorder (OCD) – anxiety symptoms are in the form of intrusive, obsessive thoughts and compulsive behaviors (or mental acts). OCD is considered a chronic type of anxiety disorder.
  • Post traumatic stress disorder (PTSD)– anxiety symptoms that occur after a trauma and are long-term in nature.
  • Social phobia, also referred to as Social Anxiety Disorder – anxiety symptoms occur in social or performance situations and stem from the fear of being humiliated or embarrassed.
  • Specific phobia or a simple phobia– anxiety symptoms occur around a specific object or situation which results in avoidance.

Psoriasis sufferers have reported more stressful life events in comparison with control subjects. The link between psoriasis and anxiety can be analyzed in two ways – anxiety can lead to psoriasis and psoriasis can lead to anxiety. Also research has confirmed that an increase in severity of psoriasis leads to an increasing frequency of anxiety. The magnitude of this anxiety may be influenced by variables of disease e.g. severity, distribution of lesions, duration of condition and nail and joint involvement. Likewise it should also be noted that variables of life e.g. age, gender and marital status influence psoriasis associated anxiety and depression. 3

Eating Disorders – Obesity 4,5

Increasing evidence suggests that patients with psoriasis may be more obese compared with the general population. Although the exact mechanism underlying the association between psoriasis and obesity is uncertain, researchers have theorized that adipocytes (fat cells) as a rich source of pro-inflammatory cytokines may exacerbate psoriasis.

Which Comes First? Obesity or Psoriasis?

The answer to this question remains unknown as the precise mechanism underlying the association between psoriasis and obesity remains elusive. However, two longitudinal prospective cohort studies found weight gain or obesity; particularly from the age of 18 years was a risk for developing psoriasis in women. It still bust be noted that not all psoriasis sufferers are obese and not all obese individuals develop psoriasi

Mood Disorders (Depressive Disorders and Bipolar Disorder)6

Research has recently considered whether psoriasis is a psycho-dermatological disorder.

A psycho-dermatological disorder is a condition that involves an interaction between the nervous and the integumentary (skin) system. Psoriasis has been found to be associated with clinical depression commonly known as major depression through an immunological phenomenon. Research has shown the possibility of a relationship between common forms of psoriasis and major depressive disorder and an increase in stress and depressive symptoms has been found to have a significant statistical correlation with an increase in psoriasis flare-ups and pruritus severity along with a more clinically disfiguring disease. In addition, studies have shown that a decrease in depression/depressive symptoms due to medication or therapy is often associated with a decrease in psoriasis severity and vice versa. Other research has found that many inflammatory markers and cytokines which are released during depression are also released during psoriasis.

Research into depression has found that it leads to an increase in the concentration of proinflammatory cytokines systemically in patients afflicted with the disease, and that these same proinflammatory cytokines migrate towards the epidermis (skin) and cause psoriatic lesions in susceptible patients, either increasing psoriasis severity or potentially leading to its initiation or a flare up. Other research has found that mutations in genes related to psoriasis cause an increase in the same proinflammatory cytokines. These cytokines can cause HPA axis (hypothalamic–pituitary–adrenal axis) hyperactivity which is observed in major depressive disorder and that this then disturbs the negative feedback inhibition of circulating corticosteroids on the said axis and leads to lower serotonergic (5-HT) neurotransmitter levels, thus leading to a depressive disorder. READ ALSO OUR PREVIOUS BLOG: – STRESS, ANXIETY,

DEPRESSION AND PSORIASIS

Bipolar Disorders

Bipolar is a significant, serious and debilitating mood disorder. If it is not bad enough that a person may have this condition, Lithium, one of the most commonly prescribed psychotropic medications for this condition, has been associated with a wide range of cutaneous side effects including the initiation and exacerbation of psoriasis. In the general population prevalence of bipolar is estimated to be 3%, the prevalence of psoriasis varies from 1–5% in Western Countries; approximately 2% of these patients will suffer from bipolar.

Lithium, which has been in use for the treatment of bipolar for over 50 years, has a long history of systemic adverse effects, including the skin. The reported prevalence of the cutaneous side effects varies from 3% to 45% in different studies. Acne/acneiform and psoriasiform rashes are among the major cutaneous adverse effects of lithium and these may result in noncompliance. It should be noted; however, not all the patients with pre-existing psoriasis show flares while they are on lithium treatment. Male patients who take lithium are more likely to develop cutaneous reactions than their female counterparts.7

 Look out for our next edition on this topic –  PSORIASIS AND COMORBIDITIES – Psychological and Psychiatric Disorders – Part 2 

REFERENCES

  • Susskind W. and McGuire R.J.: The Emotional Factor in Psoriasis; Scot. med, J., 1959,4:503
  • Kessler R. C. et al.; Epidemiology of Anxiety Disorders; M.B. Stein and T. Steckler (eds.), Behavioral Neurobiology of Anxiety and Its Treatment, Current Topics in Behavioral Neurosciences 2, DOI 10.1007/7854_2009_9, # Springer?Verlag Berlin Heidelberg 2009, published online 3 September 2009
  • Nasreen S. et al.; Frequency and Magnitude of Anxiety and Depression in Patients with Psoriasis Vulgaris; Journal of the College of Physicians and Surgeons Pakistan 2008, Vol. 18 (7): 397-400
  • Toussirot É. Et al.; Relationships between adipose tissue and psoriasis, with or without arthritis; Frontiers in Immunology; August 2014 | Volume 5 | Article 368 ; https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4129363/pdf/fimmu-05-00368.pdf
  • Aldeen, et al; Obesity and Psoriasis: Can Bariatric Surgery Trigger Psoriasis?; J Clin Exp Dermatol Res 2015, 6:6 http://dx.doi.org/http://dx.doi.org/ 10.4172/2155-9554.1000305
  • Tohid H. et al.; Major Depression and Psoriasis: A Psychodermatological Phenomenon; Skin Pharmacol Physiol 2016;29:220–230 DOI: 10.1159/000448122

 

Stressed about Your Skin Condition – Identify Your Stressors and Your Stress Responses

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Whether you suffer from Psoriasis, Eczema / Dermatitis etc. stress is a recognized trigger that initiates and exacerbates fale ups. Being able to recognize what your Stress Triggers (Stressors) may assist you in modifying your responses and be part of the learning curve in managing your condition.

Identifying your Stressors

Use the list below to identify your stressors. For each item on the list, note whether or not it is important to you and whether or not you have control over it.

Changing Jobs/Promotion      Family Conflicts                      General Health   

Lack of Confidence                  Isolation                                     Money Worries

Pain/Fatigue                              Planning for Retirement         Public Speaking

Traffic to/from Work               Travel/Vacation/Holidays       Upcoming Wedding

Social Events                           World Events: War, Natural Disasters, Economy

Other:_______________        Other:_______________

 

 IMPORTANTNOT IMPORTANT
 

 

 

You are in Control

 

 

 

    
 

 

 

You do not have Control

 

 

 

  

 

 How Does Your Body Respond to Your Stressor?

Take note of what your body is telling you. Your body may constantly show a set pattern of response to stress and, as such, if you become aware of these responses you can then take the next step in trying to control these responses. These are classified as the following:

1) Physical

2) Behavioral

3) Emotional

4) Cognitive and

5) Spiritual

 

Physical symptoms include:- Shallow or rapid breathing, rapid heat beat, headaches, nausea or indigestion, hot flushes or sweaty palms, back pain, tight shoulders and/or neck or other unusual random aches and pains, insomnia and/or excessive fatigue, Psoriasis flare up.

tiredness-sets-in-1482054-640x480 backache-1620045-639x442

Behavioral symptoms include:- Excessive smoking, abuse of alcohol and/or compulsive eating.  Compulsive chewing of gum or inner cheek or grinding one’s teeth, especially at night. Aggressiveness, bossiness and/or being over critical of others;

smoker-1457305-639x497 bad-guy-1623961-640x960have-a-drink-1-1510449-640x480

 

Emotional symptoms include:- Excessive impulse to laugh or cry, unhappiness for no reason and being easily upset. General boredom or nervousness and edginess. Extreme loneliness and/or overwhelming feelings of being powerless to change things. Over reacting and/or intense anger.

crying-1440466-640x480frustrated-1439244-640x480

Cognitive symptoms include:- Mental confusion/concentration – trouble thinking clearly or being able to do simple mental tasks e.g. adding numbers up or simply being able to read a book, forgetfulness, memory loss and loss of sense of humor.

Spiritual symptoms might include:- Loss of faith – doubt, martyrdom and just a general loss of direction in one’s life, being vulnerable to cult groups.

 

Identify Your Stressor Responses

When you know how your body responds to stressors, you can focus your attention on finding the best stress management technique for each one. Tick the box corresponding to your Body Responses as to when you feel stressed and identify what the stressor was.

SYMPTOMSSTRESSORSYMPTOMSSTRESSOR
Chest Pain

 

 Fatigue 
Chest Tightness

 

 Lack of Energy 
Heart Palpitations

 

 Difficulty Sleeping 
Headache/Migraines

 

 Depression/Anxiety 
Neck & Shoulder Pain

 

 Sadness 
Teeth Grinding

 

 Crying 
Backache

 

 Irritability/Anger 
Muscle Crams/Spasms

 

 Frustration 
General Muscle Tension Forgetfulness

 

 
Pain

 

 Worrying 
Upset Stomach/Nausea

 

 Restlessness 
Diarrhea / Constipation

 

 Lack of Motivation 
Increased Smoking

 

 Blaming Others 
Increased Alcohol Consumption Loneliness 
Excessive eating for the sake of eating, not when hungry Skin Flare-up (State the Condition) ________________

e.g. psoriasis

 

 

Now Rate the Severity of Your Stress Response

 

0       1        2        3       4        5       6       7        8        9       10

l____l____l____l____l____l____l____l____l____l____l

 

Not                        A little                   Somewhat                Very                        Extremely

troubled                troubled                 troubled                 troubled                    troubled

Date/TimeStress Level

(0-10)

What Did I Do?What Did I Think?
E.G.   9.30pm10Argument with Partner Yelled and stormed outI hated myself, I hated him/her, I hated life, I hated the way I felt
 

 

 

   
 

 

 

   
 

 

 

   
 

 

 

   
 

 

 

   
 

 

 

   
 

 

 

   
 

 

 

   

 

Also read our blog “Stress, Anxiety, Depression and Psoriasis”, Simple Physical Relaxation Techniques for Psoriasis Patients, Simple Mental/Mind Relaxation Techniques Part 1 – For Psoriasis Patients, Simple Mental/Mind Relaxation Techniques Part 2 – For Psoriasis Patients”

 

 

 

References

 

  1. Bamber, Petrina Nicole, “Quality of life for patients with psoriasis : more than skin deep” (2009). Master’s and Doctoral Projects. Paper 272. http://utdr.utoledo.edu/graduate-projects/272
  2. National Center for Health Promotion and Disease Prevention (NCP); Manage Stress Workbook; http://www.prevention.va.gov/mpt/2013/docs/managestressworkbook_dec2013.pdf
  3. Franklin C.L. et al.: Relaxation Enhancement Therapist Manual; http://www.mirecc.va.gov/visn16/docs/Franklin_Relaxation_Therapist_Manual.pdf

Stress, Anxiety, Depression and Psoriasis

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A rapid heartbeat, headache, stiff neck, backache, rapid breathing, sweating and upset stomach are a few of the everyday physical symptoms of stress, anxiety or depression. There is a growing medical consensus of opinion that many skin diseases are strongly associated with psychological stress and illness. The relationship of stress, anxiety, depression, not to mention feelings of stigma, shame, embarrassment, and low self-esteem all impact upon a person who is suffering from psoriasis. 1, 2

The interplay between stress and multiple biologic systems in our bodies can trigger the onset of psoriasis. For many anxiety or depression is a symptom after the event, especially if the condition is chronic and especially visual and/or painful.

Regardless of how stress is defined, studies conducted show a consistent relationship between stress and psoriasis.  The majority of psoriasis sufferers, themselves, also consider stress to be the main cause for or exacerbation of their psoriasis, ranking it above infections, trauma, medications, diet, or weather.

Studies have defined stress into three general categories:                                                     sorrow-and-worry-1434793 FreeImages

1) Major stressful life events (e.g., employment or financial problems,

    death of a spouse, major personal illness),

2) Psychological or personality difficulties, and

3) Lack of social support.

In one study patients were questioned as to what types of stressful life events that had occurred in the previous 12 months, that could have triggered their skin condition.

Stressful life events were seen in 26% of the psoriasis patients, the most common stressful life event seen was financial loss or problems (8%), death of close family member (4%), sexual problems (4%), family conflict (2%), major personal illness or injury (2%), change in working conditions (2%), failure in examinations (2%), family member unemployed (2%), illness of family member (2%), getting married or engaged (2%) and miscellaneous (2%). 5

 It is important to recognize that psoriasis is a lifelong disease that affects patients not only physically but also socially and emotionally. As seen from the patients’ perspective, the most severe negative effects of their skin condition do not result from physical symptoms alone, but rather from the interaction of their physical symptoms and their mental/emotional state. Researchers have found that the stress of having psoriasis, in itself can initiate or exacerbate depression in depression-prone individuals.

The challenge for sufferers of skin conditions is, with the aim of improving their quality of life, to help themselves to find, together with their practitioner, the best personal treatment plan and then sticking to it. The main challenges in the effective management of skin conditions, comes down to patient adherence to the treatment plan and their emotional resilience.

 

References

  1. Biljan D. et al.: Psoriasis, Mental Disorders and Stress, Coll. Antropol. 33 (2009) 3: 889–892
  2. Buske KIrschbaum Hellhammer et al.,; Endocrine and immune responses to stress in chronic inflammatory skin disorders; 992. 231-240 (2003)
  3. Gerhard Schmid-Ott et al.,; Patient considerations in the management of mental stress in psoriasis; Patient Intelligence 2012:4 41–50; 2012 publisher and licensee Dove Medical Press Ltd.
  4. Malhotra SK, Mehta V. Role of stressful life events in induction or exacerbation of psoriasis and chronic urticaria.; Indian J Dermatol Venereol Leprol 2008;74:594-9.
  5. Madhulika A. Gupta. Et al.; A Psychocutaneous Profile of Psoriasis Patients, Who Are Stress Reactors, A Study of 127 Patients; Gen Hosp Psychiatry;11, 166-173, 1989
  6. Jafferany M. Psychodermatology: A Guide to Understanding Common Psychocutaneous Disorders.Primary Care Companion to The Journal of Clinical Psychiatry. 2007;9(3):203-213.