Psoriasis Causes

A risk factor is something that increases your likelihood of getting a disease or condition.

It is possible to develop psoriasis with or without the risk factors listed below. In fact, most cases of psoriasis are not associated with any of the risk factors listed below. However, the more risk factors you have, the greater your likelihood of developing psoriasis. If you have a number of risk factors, ask your doctor what you can do to reduce your risk.

Risk factors include:

Genetic Factors

There is a strong genetic component to psoriasis. In about one third of all cases, there is a family history of psoriasis.

Certain Medical Conditions

Medical conditions that are most likely to trigger psoriasis include:

Stress/emotional disorders:Stress, suppressed anger, anxiety, depression, or other emotional disorders often trigger psoriasis outbreaks.

Infection:Psoriasis frequently flares up after upper respiratory infections, such as tonsillitis, sinusitis, or strep throat.

Skin injuries:Psoriasis may develop at the site of a previous skin injury or mild abrasion, such as a cut, burn, or injection. This delayed development of psoriasis at these injured skin sites is known as the Köbner Phenomenon.

HIV/AIDS:Psoriasis may become particularly severe in people infected with HIV/AIDS.

Obesity:There is some evidence that obesity may exacerbate psoriasis.

Alcoholism:It is not entirely clear whether alcoholism is a risk factor for developing psoriasis or vice versa (due to the emotional burden of psoriasis). In any case, consuming excessive amounts of alcohol should be discouraged, especially during periods of psoriasis exacerbation.

Certain Medications

Certain medications have been associated with triggering or exacerbating outbreaks of psoriasis. These include:

• Beta-blocker and angiotensin-converting enzyme (ACE) inhibitors:Used to treat high blood pressure
• Lithium:Used to treat severe depression or bipolar disorder
• Hydroxychloroquine and Chloroquine:Used to prevent malaria
• Non-steroidal anti-inflammatory drugs (NSAIDs):Certain types of NSAIDs, such as indomethacin, may cause or worsen psoriasis; however, other types of NSAIDs may actually improve psoriatic symptoms.

Age

Plaque psoriasis first appears during 2 peak age ranges. The first peak occurs in persons aged 16-22 years, and the second occurs in persons aged 57-60 years. It is considered quite rare in infants, but may occur in children before the age of 10.

Racial/Ethnic Background

Psoriasis is more prevalent in fair-skinned people, particularly those who have a blood relative with psoriasis. It is less common in people with darker skin.

Environment

Psoriasis is often triggered by weather and climatic conditions. In general, people living in cold, dry climates are at much greater risk of developing psoriasis than people living in temperate or warm climates. In fact, warm, humid weather helps to heal psoriasis symptoms.

References:

Azfar RS, Gelfand JM. Psoriasis and metabolic disease: epidemiology and pathophysiology. Curr Opin Rheumatol. 2008 Jul;20(4):416-22.

Behnam SM, Behnam SE, Koo JY. Alcohol as a risk factor for plaque-type psoriasis. Cutis. 2005 Sep;76(3):181-5.

Kirby B, Richards HL, Mason DL, Fortune DG, Main CJ, Griffiths CE. Alcohol consumption and psychological distress in patients with psoriasis. Br J Dermatol. 2008 Jan;158(1):138-40.

National Institute of Arthritis and Musculoskeletal and Skin Diseases website. Available at: http://www.niams.nih.gov/ .

National Psoriasis Foundation website. Available at: http://www.psoriasis.org/home/ .