Many epidemiological studies have confirmed the relationship of obesity and psoriasis, and it is believed that obesity is an independent risk factor for its development and is associated with a worse prognosis. Furthermore, the reduction of body weight, using low-calorie diet combined with exercise, reduces the severity of psoriasis.Visceral adipose tissue is the largest endocrine organ, producing proinflammatory cytokines (TNF-α, IL-6, IL-17) and adipokines (adiponectin, omentin, chemerin). They participate in the development of dyslipidemia, insulin resistance, diabetes, and consequently of the cardiovascular diseases. Macrophages of visceral adipose tissue have a special role and they increase significantly in obesity. They are responsible for the development of inflammation in adipose tissue and produce inflammatory cytokines (TNF alpha, IL-6, Il-8, Il-17, Il-18, MCP-1) and other adipokines: resistin, visfatin, retinol-binding protein 4. This explains the concept of «psoriatic march «and observations of the frequent coexistence of psoriasis with obesity. Inflammation associated with systemic disease, fanned by pro-inflammatory cytokines and adipokines produced by the visceral adipose tissue lead to the development of insulin resistance, endothelial cell damage. Endothelial dysfunction predisposes to the formation of atherosclerotic plaques and faster development of cardiovascular events. Complication of obesity is the development of non-alcoholic fatty liver disease (NAFLD), which states twice as likely in patients with plaque psoriasis and is associated with the severity of the disease. Another consequence is the development of depression. Probably the proinflammatory cytokines can interact with metabolism of neurotransmitters. Obesity also has a significant impact on the treatment of psoriasis, increasing the risk of adverse effects of systemic drugs, reducing the efficacy of biological agents which dose should be adjusted to the weight of the patient. It is a factor responsible for the increased volume of distribution and it causes low titter of drug concentration.
Keywords: Obesity; Psoriasis; adipokines; adipokiny; metabolic syndrome; otyłość; zespół metaboliczny; łuszczyca.