Prescription opioids and longitudinal changes in cognitive function in older adults: A population-based observational study

Background: Opioids are frequently prescribed to alleviate pain in older adults, yet the relationships between prescription opioids and long-term cognitive function are unclear. Methods: In this analysis of the Mayo Clinic Study of Aging, a longitudinal population-based cohort study of older adults with formal neuropsychological testing and cognitive evaluations performed every 15 months, the associations between prescription opioids, global and domain-specific cognitive function, and mild cognitive impairment were evaluated through time-dependent linear mixed effects and Cox proportional hazards models. Results: Four thousand two hundred eighteen participants (51% male) were included with enrollment between 11/1/2004 and 4/1/2019 and median age of 76 (interquartile range 72, 82) years. Two thousand nine hundred seventy-seven subjects (71%) received at least 1 opioid prescription during a median follow-up of 7.5 (5.0, 10.7) years. Overall, there was an estimated 0.096 reduction in the global cognitive Z-score per year, including decreases of 0.050 in memory, 0.080 in language, 0.044 in visual–spatial cognition, and 0.112 in attention. In multivariable analyses, each receipt of an opioid prescription resulted in an additional −0.007 (95% CI −0.009, −0.005) change in global cognitive Z-score (p < 0.001), with significant effects seen in the domains of memory (−0.005, 95% CI −0.007, −0.003; p < 0.001), language (−0.002, 95% CI −0.003, 0.000; p = 0.024) and attention (−0.004, 95% CI −0.006, −0.002; p < 0.001) but not visual–spatial function (0.000, 95% CI −0.001, 0.001; p = 0.897). Opioid prescriptions were associated with incident mild cognitive impairment (MCI) in adjusted analysis (hazard ratio 1.21, 95% CI 1.04, 1.42; p = 0.014). Conclusion: Prescription opioids are associated with small but statistically significant declines in long-term cognitive function in older adults, which may represent effects of opioids or other related factors.