Psoriasis and the metabolic syndrome.

Chronic plaque psoriasis is an immune-mediated inflammatory skin disease that is strongly associated with the clinical features of the metabolic syndrome (MetS), including abdominal obesity, hypertension, atherogenic dyslipidemia, type 2 diabetes, insulin resistance, and nonalcoholic fatty liver disease. The strength of these associations has been repeatedly confirmed by several observational studies. In particular, the prevalence of MetS in patients with psoriasis ranges from 20% to 50%, with a risk of having MetS is at least double in psoriatic patients compared with nonpsoriatic control individuals. MetS is also more common in patients with severe psoriasis than in those with mild skin disease. Emerging evidence now suggests that psoriasis and MetS share multiple metabolic risk factors, genetic background, and pathogenic pathways. The association between psoriasis and MetS has important clinical implications. Systemic conventional treatments should be used with caution in psoriatic patients with MetS, because they could adversely affect the coexisting metabolic disorders, especially in the case of their chronic use. Biologics appear to have a different safety profile compared with conventional treatments, and so they are usually tolerated. Collectively, dermatologists should pay close attention to the early recognition of coexisting metabolic disorders and give appropriate pharmacologic and nonpharmacologic (hypocaloric diet and regular exercise) recommendations to their patients.