The Longitudinal Association Between Chronic Back Pain and Cognitive Decline in Older Adults With Mediation Analysis: An Analysis of Four Population-Based Databases

Background: While studies suggest chronic back pain (CBP) may heighten accelerated cognitive decline risk in older adults, no multinational research has comprehensively examined this significant public health concern alongside healthy lifestyles' potential impact. Methods: Data from 18,558 individuals across 17 countries (China, England, Europe, USA) were extracted from four databases (2010–2023; median follow-up: 8.4 years). Associations between CBP and memory-related diseases (MDs), cognitive function performance metrics (e.g., numeracy, orientation, immediate word recall, delayed word recall memory, and an overall cognitive score combining these elements), and subjective cognitive decline (SCD) were analysed using linear mixed-effects models and conducting mediation analysis through Structural Equation Modelling, adjusting for confounders. Results: CBP significantly elevated MD and SCD risks in the USA (MDs: OR 1.03 to 1.47; SCD: OR 1.03 to 1.04) and Europe (MDs: HR 1.18 to 2.15; SCD: HR 1.01 to 1.03). Pooled meta-analyses confirmed significant but weak associations: MDs (OR = 1.35, 95% CI 1.03 to 1.68), delayed recall (β = −0.05, 95% CI −0.09 to −0.02), and SCD (HR = 1.02, 95% CI 1.00 to 1.03). Mediation analyses identified alcohol intake as exacerbating cognitive decline, while smoking cessation, physical activity, and sleep (7–9 h) reduced risks in older adults with CBP. Conclusions: CBP heightens accelerated cognitive decline risks in older adults, mediated by modifiable lifestyle factors. These findings emphasise cognitive monitoring and tailored lifestyle interventions, particularly smoking cessation, activity promotion, and sleep optimisation in older adults with CBP. Multidimensional approaches integrating physical and behavioural strategies are critical to mitigating cognitive impairment in this population. Significance Statement: CBP increases the risk of cognitive decline in older adults, underscoring the importance of preventing cognitive decline in this population. Public health initiatives should prioritise interventions that target CBP management and lifestyle modifications to mitigate the risk of pain and cognitive decline.