The Burden, Risk Factor Analysis, and Prediction of Low Back Pain in China From 1990 to 2021

The burden of low back pain (LBP) in China poses a substantial public health challenge. This study aimed to analyze longitudinal trends in the burden of LBP and its associated risk factors based on data from the Global Burden of Disease (GBD) 2021 study and to project future trends.

Epidemiological data for LBP in China and globally were retrieved from the GBD 2021 database. Disease burden was characterized using summary tables and age-dependent line graphs. Joinpoint regression analyses were used to investigate temporal trends in incidence rates and risk factors in China. The periods between identified joinpoints were analyzed by decomposition analysis to investigate the drivers of change. A log-linear Poisson age-period-cohort model was fitted to age-period-specific incident counts, with the corresponding population exposure included as an offset, to estimate age, period, and birth cohort effects on LBP incidence. Finally, a Bayesian age-period-cohort (BAPC) model was used to predict the trend of the age-standardized incidence rate of LBP in China.

From 1990 to 2021, the number of prevalent cases and total years lived with disability (YLDs) due to LBP increased both globally and in China, while the age-standardized prevalence rate (ASPR) and age-standardized YLD rate (ASYR) decreased. The joinpoint regression analysis of incidence rates identified four significant turning points in China, which defined five periods over the past 30 years. Decomposition analyses identified aging as a key driver of increased incident cases and showed the escalating impact of population growth. Occupational ergonomic factors were the main contributors to ASYR, while the impact of high BMI escalated significantly, reaching an annual percentage change (APC) of 3.65 in 2008-2021. Smoking was the most prominent factor for middle-aged and older men. BAPC posterior means showed a marginal increase in incidence rates among men and a slight decrease among women; however, the 95% credible intervals widened substantially and overlapped by 2036. These findings should be interpreted as uncertain posterior mean patterns rather than firm future trends.

The absolute burden of LBP in China has increased over the past 30 years in the context of demographic shifts, while age-standardized rates have trended downward. The timing of this decline partly coincided with the implementation of key national health policies, raising the hypothesis that these policies may have contributed to the observed population-level changes. However, temporal alignment in this descriptive ecological analysis does not establish causality or demonstrate policy effectiveness. To address the continuing burden, occupational health, weight management, and tobacco control remain important areas for prevention.