Background Pain is prevalent in older adults (≥65) and may be managed using opioids. Frail older populations may have greater risk of cognitive adverse effects. These are distressing, but evidence to inform our understanding is limited.

Aim To understand opioid use in frail older adults’ pain management, their impact on cognition, and explore related experiences regarding these.

Methods Convergent parallel mixed-methods study, comprising (1) cross-sectional survey and case notes review, among frail older adults, and (2) semi-structured interviews with a subset of participants from 1 and their informal carers). (1) Descriptive and comparative statistics and (2) thematic analysis were used.

Results 247 participants were recruited (median age 81, range 65–99, 38.9% male). >50% had moderate to severe pain on recruitment. 51.8% had an opioid prescription over the past year with limited review. A logistic regression analysis (n=217) showed pain severity and number of medications were associated with increased odds of an opioid prescription (OR: 1.74, 95% CI [1.32, 2.29], p=.000 and OR: 1.13, 95% CI [1.03, 1.123], p=.006, respectively). Median health-related quality of life scores were poorer for those with an opioid than those without (Mann-Whitney U = 4142.0, n=222, p<.001). 48 of 155 participants self-reporting a pain medication reported at least one cognitive adverse effect. Recall of cognitive adverse effects improved when prompted by a list. Cognitive adverse effects were bothersome to participants, requiring substantial work to manage them alongside chronic pain and opioid use, and impacted everyday life. Participants required clearer communication regarding opioids and frequent pain management reviews.

Conclusions Opioids are commonly prescribed to manage chronic pain and often lead to cognitive adverse effects, which are distressing to older adults and informal carers. Pain remains prominent in older adults despite treatment. Frequent review of opioids and using a prompt list of adverse effects could improve pain management.