Importance: Determining psoriasis prevalence is fundamental to understanding the burden of the disease, the populations most affected, and health policies to address the disease.
Objective: (1) To determine the prevalence of psoriasis among adults in the US and (2) to evaluate the change in psoriasis prevalence over time since the 2003-2004 National Health and Nutrition Examination Survey (NHANES) data.
Design, setting, and participants: This population-based cross-sectional study used 2011-2014 NHANES data (collected from January 1, 2011, to December 31, 2014) with sampling from a general, noninstitutionalized US civilian population. Participants were 20 years or older and were selected via a multistage probability sampling design to ensure that surveys were nationally representative. Eligible participants had an in-person interview followed by a medical examination by medical professionals. Data were analyzed from July 15, 2019, to December 23, 2020.
Main outcomes and measures: Psoriasis prevalence in the US, as measured by the percentage of people in the representative sample with psoriasis, and trend statistics comparing prevalence estimates from the 2003-2004, 2009-2010, and 2011-2014 NHANES cycles.
Results: A total of 12 625 participants (mean [SD] age, 32.8 [24.1] years; 6492 women [51.4%]; and 4828 non-Hispanic White participants [38.2%]) answered the question of whether they were given the diagnosis of psoriasis by a physician or another health care professional. Psoriasis prevalence among US adults 20 years or older was 3.0% (95% CI, 2.6%-3.4%). Based on the 2020 US census data, this outcome translates to an estimated 7.55 million US adults with psoriasis. Psoriasis prevalence was similar between women and men, with 3.2% (95% CI, 2.6%-3.8%) in women and 2.8% (95% CI, 2.4%-3.3%) in men. Psoriasis prevalence was highest in White individuals at 3.6% (95% CI, 2.9%-4.2%), followed by other racial/ethnic groups (non-Hispanic, including multiracial) at 3.1% (95% CI, 1.2%-5.1%), Asian individuals at 2.5% (95% CI, 1.6%-3.3%), Hispanic individuals (including Mexican American and other Hispanic individuals) at 1.9% (95% CI, 1.3%-2.5%), and Black individuals at 1.5% (95% CI, 1.0%-2.0%). Psoriasis prevalence was not different based on patients' marital status, education, income, or medical insurance status. The prevalence of psoriasis among US adults did not differ significantly since 2003.
Conclusions and relevance: The results of this cross-sectional study suggest that psoriasis remains a common, immune-mediated disease that affects 3.0% of the US adult population, or more than 7.5 million adults. Its prevalence has not differed since evaluation in 2003. These prevalence data are foundational to determining the burden of psoriasis and for supporting efforts in research, education, and health policy.