Longitudinal association between chronic pain and cognitive decline in cancer survivors: evidence from the CHARLS

Abstract Objective To investigate the association between chronic pain and cognitive function in community-dwelling cancer survivors. Methods Using five waves of data from the China Health and Retirement Longitudinal Study (CHARLS), a cohort of community-based cancer survivors was established. Baseline chronic pain status was used to classify exposure groups, and the occurrence of cognitive dysfunction was defined as the endpoint. We employed Cox proportional hazards regression models to evaluate the association between chronic pain and cognitive dysfunction. Results The study included 640 participants, with a chronic pain prevalence of 38.3% and a cognitive dysfunction incidence of 36.9%. Multivariate Cox regression demonstrated that chronic pain was independently associated with cognitive dysfunction risk (HR = 1.479, 95%CI: 1.134–1.930). Compared to cancer survivors without pain, those with headaches (HR = 1.725, 95%CI: 1.260–2.360),Shoulder–neck pain (HR = 1.641, 95%CI: 1.193–2.257), and multisite pain (HR = 1.653, 95%CI: 1.248–2.190) exhibited elevated risks. Gender-stratified analysis revealed that males with limb pain had the highest risk (HR = 2.307, 95%CI: 1.383–3.848), while females with headaches showed the most significant risk (HR = 1.903, 95%CI: 1.330–2.723). Stratification by chemotherapy/radiotherapy status indicated that untreated individuals with shoulder–neck pain (HR = 2.040, 95%CI: 1.414–2.943) and multisite pain ( HR = 1.819, 95%CI: 1.281–2.392) faced higher risks, whereas treated patients with headaches had elevated cognitive dysfunction risk (HR = 1.972, 95%CI:1.029–3.783). Conclusion Chronic pain and cognitive dysfunction are prevalent among community-dwelling cancer survivors. Chronic pain, particularly headaches, Shoulder–neck pain, and multisite pain, is associated with increased cognitive dysfunction risk. Targeted screening and preventive measures for cognitive dysfunction are warranted in these subgroups.