Cause, symptoms and treatment of psoriasis
What is Psoriasis?
Psoriasis is a common chronic, relapsing, non-contagious skin disorder characterised by red patchy lesions, with grey or silvery-white, dry scales, which are frequently painful, itchy and may bleed. Lesions are typically distributed symmetrically on the scalp, elbows, knees and essentially any part of the body. It is a disease with an unpredictable course, prone to flare-ups and remissions, and which can affect the joints, nails and eyes [1, 2]. Psoriasis is found worldwide but the prevalence varies among different ethnic groups. It affects 1-5% of Europeans overall, with rates as high as 6% in France and Germany. In the UK, it is the 3rd most common dermatological disease, affecting approximately 1-2% of the population; this equates to approximately 1.2 million people and accounts for 10-20% of visits to a hospital dermatology unit [1, 3, 4]. It can afflict both men and women, and usually begins in early adulthood although it has been reported at birth. The mean age of onset for the first presentation of psoriasis can range from 15-20 years of age, with a second peak occurring between ages 55-60 years.
Psoriasis is generally categorised into one of three severities based on the extent of body surface covered. Where 2% of the body is affected, it is classified as mild, where 3-10% of the body is covered, it is classified as moderate and where more than 10% of the body is affected, the disease is classified as severe. Based on these criteria, approximately 25-30% of patients have psoriasis, which is considered moderate to severe.
Causes or Risk Factors
The exact cause of psoriasis is unknown; however, numerous studies have attempted to define the risk factors for developing psoriasis. The following have been named as risk factors for the development of psoriasis,
1. Family history (genetics)
This is the most well established risk factor for the development of psoriasis. Approximately 40% of patients with psoriasis have a family history amongst first-degree relatives. It has also been noted that psoriasis develops in as many as half of the siblings when both parents have psoriasis, this falls to 16% when only one parent is affected, and 8% when neither parent is affected but there is an affected sibling.
Bacterial and viral infections may be linked to psoriasis; however, beyond streptococcus, the role of other infections in precipitating psoriasis has not been studied [4, 6].
3. Alcohol and smoking
Some studies have suggested smoking or alcohol as a cause of psoriasis. Although a large proportion of these studies have been case-control studies, based on a typical group of patients admitted to hospital, in a population based study, alcohol was shown to be a significant risk factor for mortality among patients suffering from psoriasis. Not only that, alcohol has been associated with worsening of skin disease after drinking in men and women and treatment failures. Alcohol seems to affect dermatological diseases such as psoriasis by influencing metabolism, cutaneous vasculature (arrangement of blood vessel around the skin), and the immune response. Alcohol intake can lead to liver dysfunction, when the liver cannot get rid of toxins as a result of this, the different systems in the body are affected, including the skin. The skin, trying to purge itself of toxins may result in an immune related disease, such as psoriasis. It is quite possible that alcohol may alter the expression of psoriasis and its clinical course. Abstinence from alcohol can induce remission [4, 6, 8].
The role of smoking as a risk factor for psoriasis remains elusive. According to Neimann et al (2006) in 1992, researchers in the UK evaluated 108 patients with new psoriasis and compared rates with matched controls in the community. They showed a significant association between smoking “prior to onset” and psoriasis.
Although it has often been implicated in the pathogenesis and progression of the disease, conclusive data on the role of smoking is currently lacking. As indicated by some studies, whether or not smoking causes psoriasis, cessation probably does not alter the course of the disease [4, 6].
Psoriasis may appear at the sites of trauma, including sites of sunburn, following surgery or biopsies, or even after simply scratching an area.
Posted under Over The Counter Psoriasis Treatment
This post was written by TKB_Editor on August 8, 2011