The prevalence of psoriasis in African Americans: Results from a population-based study

doi:10.1016/j.jaad.2004.07.045

Journal of the American Academy of Dermatology

Volume 52, Issue 1, January 2005, Pages 23-26

https://doi.org/10.1016/j.jaad.2004.07.045 Get rights and content

Background

Psoriasis is a common disease with substantial effects on quality of life. The prevalence of psoriasis in African Americans has been previously reported as rare. However, there have been no population-based studies to assess the prevalence and burden of psoriasis in African Americans.

Objective

We sought to measure the prevalence and burden of psoriasis in African Americans compared with Caucasians.

Methods

Patients were randomly selected from the United States population and were asked standard demographic questions. Patients who reported a physician diagnosis of psoriasis were asked additional questions related to quality of life.

Results

The total sample included 27,220 individuals of which 21,921 were Caucasian and 2443 were African American. The prevalence of psoriasis was 2.5% in Caucasian patients and was 1.3% in African American patients. African Americans had an approximately 52% reduction in the prevalence of psoriasis compared with Caucasians (P < .0001). African Americans and Caucasians had similar impacts on quality of life and treatment satisfaction based on single global questions.

Conclusion

Although psoriasis is less common in African Americans than in Caucasians, it is not rare in either demographic and carries a substantial burden in both groups.

Section snippets

Survey development, administration, and sampling techniques

A questionnaire was created to survey the epidemiologic characteristics of psoriasis in the continental US population. The survey items were generated by a committee of dermatologists in collaboration with the National Psoriasis Foundation. Items included sociodemographic variables, extent and treatment of disease, and quality of life. Patients were classified as having psoriasis if they reported having been given a diagnosis of psoriasis by a physician in the past. Those individuals with

Results

Approximately 37% of people who could be reached by a residential telephone number agreed to be interviewed regarding a variety of unrelated topics, of which approximately 77% completed the survey up to the point that psoriasis was addressed. The total sample analyzed included 27,220 individuals who completed the psoriasis questions of which 21,921 were Caucasian and 2443 were African American. Similar to US census figures, African Americans were more likely to report lower income and fewer

Discussion

To our knowledge, this is the first population-based study to investigate the prevalence of psoriasis in African Americans. A particular strength of this study is that it surveyed more than 27,000 individuals who were randomly selected from the US population and interviewed over the telephone to determine the prevalence of psoriasis. Given the broadly representative nature of the sample studied, it is expected that the findings of this study would generalize to the broader US population.

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Dr Gelfand was supported by grants from the Dermatology Foundation; the National Institute of Arthritis, Musculoskeletal, and Skin Diseases (K23 AR051125-01); and the American Skin Association. The Psoriasis Foundation gratefully acknowledges Biogen, Amgen, and Wyeth for their unrestricted grant to help make the survey possible. The Psoriasis Foundation was solely responsible for all survey content and development.

Conflicts of interest: None identified.

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ReportThe prevalence of psoriasis in African Americans: Results from a population-based study

Background

Objective

Methods

Results

Conclusion

Section snippets

Survey development, administration, and sampling techniques

Results

Discussion

J Invest Dermatol Symp Proc

Dermatol Clin

J Invest Dermatol

J Clin Epidemiol

Ann Epidemiol

Am J Prev Med

Report
The prevalence of psoriasis in African Americans: Results from a population-based study