Papers of the Week

Chronic pain (CP) was associated with impaired cognitive performance in several cross-sectional studies conducted in older adults; however, fewer longitudinal studies assessed this link which remains still debated. With a prospective design, the present analysis was aimed at evaluating the relationship between CP and the change in several tests assessing memory, attention, verbal fluency and processing speed. The study population was selected from the PAQUID study, a cohort of community dwellers aged 65 and over; 693 subjects receiving a pain assessment were included. CP was evaluated using a questionnaire administered at 3-year follow-up. Cognitive performances were assessed every 2-3 years between 3 and 15 years assessing general cognition (MMSE), verbal and visual memory (word paired associate test and Benton test) attention and speed processing (Wechsler DSST, Zazzo's cancellation task) language skills and executive functions (Isaacs set test). The link between CP and the change in cognitive function was assessed with latent process mixed models controlled for age, gender, education, comorbidities, depression and analgesic drugs. The association between CP and each of the cognitive scores was then tested with the same procedure. A significant relationship was observed between CP and poorer 15-year scores on global cognitive performance (p=0.004), and specifically DSST (p=0.002) associated with a higher slope of decline (p=0.02). CP is associated with higher cognitive decline, in particular in processing speed. This result reinforces the importance of actively treating CP with pharmacological and non-pharmacological strategies to prevent its consequences, including cognitive consequences.