Background: The global, regional, and national burden of psoriasis was investigated based on the Global Burden of Disease (GBD) study.
Objectives: To report the incidence of psoriasis in 204 countries and territories from 21 regions according to age, sex, region, country, and socialdemographic index (SDI) between 1990 and 2019.
Materials & methods: Estimates from the GBD 2019 study were used to analyse the incidence of psoriasis at the global, regional, and national levels. The estimated annual percentage changes (EAPCs) in the age-standardized incidence rate (ASIR) were calculated to quantify trends between 1990 and 2019.
Results: From 1990 to 2019, the global incidence of psoriasis increased by 26.53%, but the ASIR of psoriasis decreased, with an EAPC of -0.77 (95% confidence interval [CI]: -0.78 to -0.76). In 2019, the highest ASIRs of psoriasis (112.58 per 100,000 population; 95% uncertainty interval, 108.89 to 116.07) were observed in high-SDI regions. The male-to-female ratio for psoriasis incidence peaked globally in the 50-54-year-old age group and peaked in the 75-79-year-old age group in high-SDI regions. Regionally, Central Sub-Saharan Africa (EAPC, -0.57; 95% CI: -0.67 to -0.48) and Eastern Sub-Saharan Africa (EAPC, -0.36; 95% CI, -0.38 to -0.34) had the largest decrease in ASIR of psoriasis from 1990 to 2019. Nationally, increases in the ASIR of psoriasis was observed only in Japan (EAPC, 0.04; 95% CI: 0.02 to 0.05).
Conclusion: Globally, the incidence of psoriasis showed an increasing trend, but the ASIR of psoriasis decreased significantly from 1990 to 2019. Only Japan showed an unfavourable increasing trend.
Keywords: psoriasis; age-standardized rate; incidence; Global Burden of Disease.