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
Inflammatory Bowel Disease (IBD) –
Irritable Bowel Syndrome (IBS)
1, 2, 3
Gastro Intestinal (GI) disorders are present in 28% of patients with psoriasis. Common abnormalities in psoriasis patients include changes in the mucous membrane of the duodenum. Psoriasis may cause dermatogenic enteropathy and intestinal inflammation.
Irritable bowel syndrome (IBS) is one of the most common ‘functional’ gastrointestinal disorders accounting for 3% of all primary care consultations, with a strong female predominance. The main features are recurrent abdominal pain and/or discomfort, whose clear relationship to changes in stool frequency or consistency and its relief by defecation implies that they originate in the colon. In addition to these gastrointestinal (GI) symptoms, patients commonly report non-GI symptoms of lassitude, headache, backache, dysmenorrhoea (painful periods/menstruation), and dyspareunia (painful intercourse). Symptoms characteristically wax and wane. IBS patients, in common with other sufferers with functional GI disorders, are more anxious than healthy controls, showing greater anxiety and depression. Many patients believe that stress induces their symptoms.10
Inflammatory Bowel Disease (IBD) are a group of inflammatory conditions in which the body’s own immune system attacks parts of the digestive system. The two major types of IBD are ulcerative colitis (UC) and Crohn’s disease (CD). UC is limited to the colon and/or rectum (normally continuous lesions in the rectum and colon), and affects only the inner lining (mucosal and submucosal layers) of the gut. In contrast, CD can affect any part of the gut from mouth to anus as non-continuous or skip lesions (a majority of cases start in the terminal ileum), and affect the whole thickness of the bowel wall.4
Within the IBD group is also Microscopic Colitis, an inflammation of the colon that can only be detected with a microscope. There are two types of microscopic colitis – collagenous colitis and lymphocytic colitis. Under a microscope an increase in the number of lymphocytes, a type of white blood cell, can be seen in the epithelium—the layer of cells that lines the colon.15
The two types of colitis affect the colon tissue in slightly different ways:
- Lymphocytic colitis – The number of lymphocytes is higher, whilst the tissues and lining of the colon are of normal thickness.
- Collagenous colitis – The layer of collagen, a threadlike protein, underneath the epithelium builds up and becomes thicker than normal.
The most common symptom of microscopic colitis is chronic, foul smelling, watery, non-bloody diarrhoea. Episodes of diarrhoea may last for weeks, months, or if chronic, even years, however, there may be intermittent periods without diarrhoea. During these periods the patient may even experience bouts of constipation.
Other signs and symptoms of microscopic colitis include15:-
- A strong urgency to have a bowel movement.
- Faecal incontinence – accidental passing of stool or fluid from the rectum – especially at night.
- Pain, cramps, or bloating in the abdomen – that is usually mild but can be incapacitating.
- Weight loss/gain
- Nausea – usually without vomiting.
- Dehydration – as a result from not drinking enough liquids to replace fluids lost through diarrhoea.
|IBD SYMPTOMS||IBS SYMPTOMS|
|Frequent and/or Urgent Bowel Movements|
Abdominal Pain & Cramping
Lack of Appetite
Joint, Skin or Eye Problems
|Abdominal Pain & Cramping|
Mucus in Stools
As far back as 1968 studies reported a prevalence of 2-3% of psoriasis in first-degree relatives of patients with CD compared to 0–3% of controls. Later studies found psoriasis in 7–11% of the IBD population compared to 1–2% of general population. In one study, psoriasis was found to be more prevalent in CD (11.2%) than UC (5.7%). 5
In one study5 the Researchers studied the presence and characteristics of psoriasis were recorded and further classified as follows: sebopsoriasis, scalp psoriasis, plaque type psoriasis [trunk, arms], palmo-plantar psoriasis, nail psoriasis, inverse psoriasis, psoriatic arthritis, guttate psoriasis, and pustular psoriasis. Psoriasis that developed after anti-TNF? treatments was also reported. Severity of psoriasis was defined as mild, moderate or severe [not applied to psoriatic arthritis]. The study involved some 251 IBD patients, there were 158 patients with CD [63%] and 93 with UC [37%]. These 251 IBD patients were referred to the dermatologist and psoriasis was detected in 62 [25%], including 36 [58%] with CD and 26 [42%] with UC. The non-IBD group included 62 patients with psoriasis. Mild psoriasis was more frequent in IBD vs non-IBD, whereas moderate and severe psoriasis were more frequent in non-IBD vs IBD. Plaque-type psoriasis was the most common phenotype in both IBD and non-IBD. The frequency of plaque-type, nail psoriasis and psoriatic arthritis was lower in IBD vs non-IBD.
Other researchers analyzed the health records of 174,646 participants from the Nurses’ Health Study (NHS) and NHS II in an effort to also determine whether IBD was associated with specific psoriasis phenotypes. In this study they found 4,400 cases of psoriasis and of these 423 participants had developed CD or UC with a prevalence of psoriasis that was four to six times greater in IBD patients than the estimated prevalence in the general public.6
Several neutralizing anti-TNF agents, such as etanercept and infliximab, have been successfully used to treat autoimmune diseases, including inflammatory bowel disease. However, paradoxically, Infliximab and adalimumab-induced psoriasis in Crohn’s disease has been identified as a side effect of TNF-alpha inhibitor therapy. Researchers reviewed 142 case articles of new-onset psoriasis with infliximab, adalimumab, and etanercept therapy and of these confirmed eighty-one cases of infliximab induced psoriasis.7 In another study the researchers found that the vast majority of the cases (76%) developed psoriasis while on infliximab, and the rest (24%) after switching to adalimumab or certolizumab, indicating that this phenomenon is not drug specific, but rather a pharmacological group effect 12
In another systematic literature review Researcher reviewed 222 cases. Of the 222 patients, 78.38% were diagnosed with Crohn’s disease, and 48.20% were female. The mean patient age was 26.50 years, and 70.72% of patients had no prior history of psoriasis. Infliximab was the anti-TNF-? therapy that caused the cutaneous reaction in most patients (69.37%). Clinical presentation varied; psoriasis-form lesions were the most common form of psoriasis (55.86%), followed by typical plaque type lesions (20.72%), and pustular-type lesions (3.60%). Six patients (2.70%) concomitantly presented with alopecia, one patient (0.45%) presented with palmoplantar pustulosis, and another patient (0.45%) presented with palmoplantar pustulosis and psoriatic arthritis.9
Celiac disease is defined as a disease of the small intestine characterized by mucosal inflammation, villous atrophy, and crypt hyperplasia upon exposure to dietary gluten. Several studies have found that psoriasis patients are at an increased risk for celiac disease. A retrospective cohort study compared 25,341 psoriasis patients to over 125,000 matched controls in the U.S. The comparison data showed an odds ratio of 2.2 for the association of psoriasis with celiac disease. They also examined whether patients with celiac disease also have increased risk of psoriasis. A cohort of 28,958 biopsy-confirmed celiac disease patients from Sweden was evaluated for risk of future psoriasis compared to 143,910 age and sex-matched controls. The authors found a positive correlation between celiac disease antibody positivity and an increase in the severity of psoriasis or psoriatic arthritis. Interestingly, in the psoriasis patients, elevated celiac disease antibodies did not necessarily correspond to a biopsy-confirmed diagnosis of celiac disease, suggesting that psoriasis may be associated with gluten “sensitivity” (marked by antibody positivity) but not necessarily fully developed Celiac disease.10
In summary both Psoriasis and IBD and IBS are related inflammatory diseases. The skin and bowel represent both barrier and connection between the inner and the outer sides of the body. On average approximately 25% of patients who experience some form of bowel complaint will be diagnosed with psoriasis. It is also interesting to note that smoking in both IBD/IBS and psoriasis is considered an exacerbating trigger.
- Arzu K?l?ç, Seray Cakmak; PSORIASIS AND COMORBIDITIES; EMJ Dermatol. 2013;1:78-85.
- Howa Yeung et al.;Psoriasis Severity and the Prevalence of Major Medical Comorbidity – A Population-Based Study; JAMA Dermatol. 2013;149(10):1173-1179. doi:10.1001/jamadermatol.2013.5015
- Aurangabadkar SJ. Comorbidities in psoriasis. Indian J Dermatol Venereol Leprol 2013;79, Suppl S1:10-7
- Huang B.L. et al.; Skin manifestations of inflammatory bowel disease; Frontiers in Physiology; www.frontiersin.org February 2012 | Volume 3 | Article 13 | 1
- Skroza et al.; Correlations between Psoriasis and Inflammatory Bowel Diseases; Hindawi Publishing Corporation BioMed Research International Volume 2013, Article ID 983902, 8 pages ; http://dx.doi.org/10.1155/2013/983902
- Lolli E. et al.; Psoriasis Phenotype in Inflammatory Bowel Disease: A Case-Control Prospective Study; Journal of Crohn’s and Colitis, 2015, 699–707 doi:10.1093/ecco-jcc/jjv068 Advanced Access publication April 23, 2015
- Li W.Q. et al.; Psoriasis, psoriatic arthritis and increased risk of incident Crohn’s disease in US women; Ann Rheum Dis. 2013 July ; 72(7): 1200–1205. doi:10.1136/annrheumdis-2012-202143
- Famenini S. and Wu J.J.; Infliximab-Induced Psoriasis in Treatment of Crohn’s Disease-Associated Ankylosing Spondylitis: Case Report and Review of 142 Cases; J Drugs Dermatol.2013;12(8):939-943.
- Denadai R .et al.; REVIEW ARTICLE Induction or exacerbation of psoriatic lesions during anti-TNF-? therapy for inflammatory bowel disease: A systematic literature review based on 222 cases; Journal of Crohn’s and Colitis (2013) 7, 517–524
- Bhatia B.K. et al.; Diet and Psoriasis: Part 2. Celiac Disease and Role of a Gluten Free Diet; J Am Acad Dermatol. 2014 August ; 71(2): 350–358. doi:10.1016/j.jaad.2014.03.017.
- Spiller R.C.; Irritable bowel syndrome; Published Online March 14, 2005; British Medical Bulletin 2004; 72: 15–29
- Longstreth GF, Thompson WG, Chey WD, Houghton LA, Mearin F, Spiller RC. Functional bowel disorders. Gastroenterology. 2006 Apr. 130(5):1480-91.
- Bercik P. et al.; Is irritable bowel syndrome a low-grade inflammatory bowel disease?; Gastroenterol Clin North Am.2005 Jun;34(2):235-45, vi-vii.
- Gionata Fiorino , Paolo D. Omodei; Psoriasis and Inflammatory Bowel Disease: Two Sides of the Same Coin?; Journal of Crohn’s and Colitis, 2015, 1–2
- Microscopic colitis. Mayo Clinic website.mayoclinic.org/diseases-conditions/microscopic-colitis/home/ovc-20192308