Pain Trajectory and Risk of Incident Chronic Lung Disease among Middle-Aged and Older Adults: a Longitudinal Study in China

Chronic pain is an established risk factor for chronic lung disease (CLD). However, previous studies have mainly focused on pain intensity or the number of pain sites, with limited attention to long-term pain trajectories. This study aimed to investigate the associations of pain status, longitudinal pain transitions and trajectories, and cumulative pain exposure with incident CLD. Data were obtained from the China Health and Retirement Longitudinal Study (CHARLS), including participants aged ≥ 45 years. Pain was assessed longitudinally using four approaches: baseline pain status (2015), pain status transitions (2015–2018), long-term pain trajectories (2015–2020), and cumulative pain exposure. Incident CLD was followed through 2020. Multivariable Cox proportional hazards models were used to evaluate associations of baseline pain status and pain transitions with CLD risk, while logistic regression models assessed associations of long-term pain trajectories and cumulative pain exposure with CLD risk. Sensitivity analyses were conducted to test robustness. Baseline pain was significantly associated with increased CLD risk (HR 1.25, 95