Psoriasis and mortality in the United States: Data from the National Health and Nutrition Examination Survey

Background: Psoriasis is a multifactorial disease that has been associated with multiple systemic disorders. Despite its role in mediating cardiovascular, metabolic, and pulmonary disorders, few studies have examined the independent mortality risk associated with psoriasis. Objective: To determine the independent relationship between psoriasis and all-cause mortality in a nationally representative sample of the US population. Methods: Retrospective population-based cohort study of adults and adolescents older than 10 years (N = 13 031) who participated in National Health and Nutrition Examination Surveys (2003-2006 and 2009-2010). Psoriasis status was determined from a self-reported medical history questionnaire. Mortality data are linked from national databases. Results: Psoriasis was present in 2.7% of the study population. Over an average median follow-up of 52.3 months, psoriasis was significantly associated with increased mortality risk (HR, 1.99; 95% CI, 1.01-3.93; P = .047) with adjustment for demographics, smoking, and comorbidities including cardiovascular disease, diabetes, chronic obstructive pulmonary disease, cancer, chronic kidney disease, and stroke. These comorbidities mediated 15.5%, 5.9%, 8.7%, 11.7%, 4.2%, and 4.7% of the association between psoriasis and mortality, respectively. Conclusion: Psoriasis is independently associated with an increased risk of mortality. This relationship is partially mediated by an increased prevalence of the cardiovascular, infectious, and neoplastic disorders seen among patients with psoriasis.