Objective:This study aims to analyze the disease burden trends of schizophrenia and bipolar disorder from 1990 to 2021 in China, and to predict the trends of these two disorders over the next 20 years.Methods:This study was conducted between September and October 2024. The data on incidence, prevalence, and disease burden of schizophrenia and bipolar disorder in China were retrieved from the database of the Global Burden of Disease Study 2021 (GBD2021). Temporal trends were quantified via the annual percentage change, average annual percentage change (AAPC), and their corresponding P-values, which were calculated using the empirical quantile method with the Joinpoint software. The autoregressive integrated moving average (ARIMA) model was constructed using data on the incidence, prevalence, and disease burden of schizophrenia and bipolar disorder from 1990 to 2021 to predict the trends in prevalence and disease burden of these two diseases from 2022 to 2041. Results:In China, during the period from 1990 to 2021, the age-standardized incidence rate (ASIR), age-standardized prevalence rates (ASPR), and age-standardized disability-adjusted life year (DALY) rate (ASDR) of schizophrenia all showed a fluctuating upward trend. By 2021, the AAPC of these rates was 3.83% ( P<0.001), 12.99% ( P<0.001), and 14.11% ( P<0.001), respectively, indicating a significant increase. Regarding bipolar disorder, the annual average ASIR in China significantly increased (AAPC=1.25%, P<0.001), while the annual average ASPR significantly decreased (AAPC=-1.03%, P<0.001), and the annual average ASDR showed no significant change (AAPC=-0.08%, P=0.342). The incidence of schizophrenia was mainly concentrated in the 15-34 age group. The prevalence and DALY rates of schizophrenia were on the rise across all age groups. For bipolar disorder, the peak incidence occurred between the ages of 10 and 19, with higher incidence, prevalence, and DALY rates in females compared to males. Looking ahead from 2022 to 2041, the overall ASIR, ASIR for both females and males, and ASPR for males with schizophrenia are projected to gradually increase, while the ASPR and ASDR of bipolar disorder are expected to remain stable, with females continuing to bear a higher disease burden than males. Conclusion:In China, the disease burden of schizophrenia and bipolar disorder substantially changed from 1990 to 2021, with distinct differences across gender and age-groups. The disease burden of schizophrenia is projected to keep rising in the next 20 years. It is imperative to develop targeted and precise prevention and control strategies for different populations.

Objective:This study aims to analyze the disease burden trends of schizophrenia and bipolar disorder from 1990 to 2021 in China, and to predict the trends of these two disorders over the next 20 years.Methods:This study was conducted between September and October 2024. The data on incidence, prevalence, and disease burden of schizophrenia and bipolar disorder in China were retrieved from the database of the Global Burden of Disease Study 2021 (GBD2021). Temporal trends were quantified via the annual percentage change, average annual percentage change (AAPC), and their corresponding P-values, which were calculated using the empirical quantile method with the Joinpoint software. The autoregressive integrated moving average (ARIMA) model was constructed using data on the incidence, prevalence, and disease burden of schizophrenia and bipolar disorder from 1990 to 2021 to predict the trends in prevalence and disease burden of these two diseases from 2022 to 2041. Results:In China, during the period from 1990 to 2021, the age-standardized incidence rate (ASIR), age-standardized prevalence rates (ASPR), and age-standardized disability-adjusted life year (DALY) rate (ASDR) of schizophrenia all showed a fluctuating upward trend. By 2021, the AAPC of these rates was 3.83% ( P<0.001), 12.99% ( P<0.001), and 14.11% ( P<0.001), respectively, indicating a significant increase. Regarding bipolar disorder, the annual average ASIR in China significantly increased (AAPC=1.25%, P<0.001), while the annual average ASPR significantly decreased (AAPC=-1.03%, P<0.001), and the annual average ASDR showed no significant change (AAPC=-0.08%, P=0.342). The incidence of schizophrenia was mainly concentrated in the 15-34 age group. The prevalence and DALY rates of schizophrenia were on the rise across all age groups. For bipolar disorder, the peak incidence occurred between the ages of 10 and 19, with higher incidence, prevalence, and DALY rates in females compared to males. Looking ahead from 2022 to 2041, the overall ASIR, ASIR for both females and males, and ASPR for males with schizophrenia are projected to gradually increase, while the ASPR and ASDR of bipolar disorder are expected to remain stable, with females continuing to bear a higher disease burden than males. Conclusion:In China, the disease burden of schizophrenia and bipolar disorder substantially changed from 1990 to 2021, with distinct differences across gender and age-groups. The disease burden of schizophrenia is projected to keep rising in the next 20 years. It is imperative to develop targeted and precise prevention and control strategies for different populations.