Analysis and comparison of the trends in burden of congenital musculoskeletal and limb anomalies in China and worldwide from 1990 to 2021

Congenital musculoskeletal and limb anomalies (CMLA) are common birth defect worldwide. This study aims to describe temporal trends of age- and gender-specific burden of CMLA in China (1990-2021), including incidence, prevalence, mortality, and disability-adjusted life years (DALYs), and to compare these with the global burden, and to predict burden changes in the next 15 years in China. Using the open access data of the Global Burden of Disease database (1990-2021), the incidence, prevalence, mortality, and DALYs of CMLA in China and worldwide were extracted. Age-standardized rates were calculated. Joinpoint regression analysis was used to calculate the average annual percentage change (AAPC) to evaluate time trends. Auto-regressive integrated moving average model was used to predict the burden in China in 2022 to 2036. Decomposition analysis was applied to evaluate the contribution of aging, population, and epidemiological changes to the change in disease burden. From 1990 to 2021, absolute numbers of incidence, prevalence, mortality, and DALYs of CMLA in China decreased by 51.54%, 16.79%, 83.02%, and 29.04%, respectively, far exceeding the global level (-3.32%, +19.13%, -28.05%, and -1.17%). The age-standardized mortality rate (ASMR) and age-standardized DALY rate (ASDR) in China decreased significantly (AAPC = -4.531% and -1.055%, respectively), and the age-standardized prevalence rate (ASPR) also decreased (AAPC = -0.584%). The age-standardized incidence rate (ASIR) was relatively stable (AAPC = 0.047%). The global ASPR, ASMR, and ASDR showed a downward trend, while ASIR was basically stable. China's burden shows a significant age shift (ages ≤29 decreases, ≥30 increases) and gender differences (male burden exceeded female across indicators). Auto-regressive integrated moving average forecasts that ASPR, ASDR, and ASMR will continue declining over the next 15 years, while female ASIR may increase slightly. Decomposition analysis showed that epidemiological changes were the main factors driving the age-standardized rate decline, and population growth hindered the decline. China has made remarkable achievements in reducing the disease burden of CMLA, at a time when the decline in the global burden has been slow and uneven. The burden in China showed the characteristics of migration from children to adults, with persistent gender differences.