High-impact chronic pain and cognitive decline among Mexicans aged 60 and older from 2012 to 2018.

Pain is associated with cognitive decline, but prior research has not considered differences between high- and low-impact chronic pain or low-and middle-income countries, such as Mexico. Our objective was to evaluate the association between high-impact chronic pain and cognitive decline among older adults in Mexico. We used data from the 2012-2018 Mexican Health and Aging Study (MHAS), a nationally representative study of older Mexican adults (60+). Pain, measured at each wave, was categorized as high-impact chronic pain (pain that limits daily activities), low-impact chronic pain (pain that did not limit daily activities), and no chronic pain. Cognition was measured at each wave using the MHAS cognitive battery, and scores were standardized for global cognitive performance, memory, and non-memory domains. We used linear mixed models with inverse probability weights to evaluate the association between pain and cognition over time. At baseline (n=9056), 19.3% of participants reported high-impact pain and 20.1% reported low-impact chronic pain. Participants with high-impact pain had lower baseline global cognition [β: -0.024, 95% confidence interval (CI): -0.045, -0.004] and memory scores (β: -0.042, 95% CI: -0.074, -0.010) compared to those with no chronic pain. Change in cognition over time did not differ by pain, except for the memory domain, where those with high-impact pain experienced slower decline compared to those with no chronic pain. Low-impact chronic pain was not associated with any cognitive outcome. Better pain treatment may result in benefits in cognitive performance for those with pain. PERSPECTIVE: We found that high-impact chronic pain was associated with worse cognition at baseline, but not with cognitive decline. Memory domains were particularly affected by high-impact chronic pain. Early pain treatment and management may provide cognitive benefits for those living with pain.