WHAT IS COMORBIDITY?
Comorbidity is a concurrence of multiple diseases or disorders in association with a given disease, in this case, psoriasis.
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
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.
- 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 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
- 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