[Global burden of psoriasis and age-period-cohort analysis and prediction from 1992 to 2021]

Objective: To analyze the age-period-cohort characteristics of the global burden of psoriasis from 1992 to 2021 and predict its future trends. Methods: Based on the Global Burden of Disease 2021 study, we employed the Joinpoint regression model to analyze trends in the incidence, prevalence, and disability-adjusted life years (DALY) of psoriasis. An age-period-cohort model was constructed to assess its impact on psoriasis incidence trends. The Bayesian age-period-cohort (BAPC) model was applied to predict the disease burden from 2022 to 2034. Results: Between 1992 and 2021, the age-standardized incidence rate and age-standardized DALY rate all exhibited an increasing trend globally in both men and women. The DALY of medium Social-demographic index (SDI) countries was the highest [1 144 223 (829 568-1 527 294)], followed by high SDI countries [975 397 (714 215-1 297 563)], medium high SDI countries [750 441 (546 290-999 446)], medium low SDI countries [599 948 (432 684-806 758)], and low SDI countries [216 728 (157 310-292 188)]. The age-period-cohort model revealed that the risk for psoriasis increased with age before peaking and then declined: the peak age for males was 55-59 years, while for females, it was delayed to 65-69 years. The incidence risk increased over time and showed a rising trend across successive birth cohorts. The BAPC model predicted a continuous increase in psoriasis incidence, with the incidence rate showing a sustained and gradual upward trend, projecting the number of new cases to exceed 5 943 801 by 2034. Conclusions: Since 1992, the burden of psoriasis has significantly increased, exhibiting regional and gender heterogeneity. The future incidence risk is expected to continue rising.