Risk of hospitalization and opioid use in older people with dementia

BACKGROUND: Older people with dementia are frequently prescribed opioids, but little is known about adverse events associated with opioid use in this population. The aim was to investigate whether opioid use was associated with an increased risk of hospitalization in older people with dementia. METHODS: Matched cohort study using Danish nationwide registries. All Danish residents (≥ 65 years) diagnosed with dementia between 2008 and 2018 were included. Individuals with opioid use in the year prior to dementia diagnosis were excluded. Exposure was first redeemed opioid prescription after dementia diagnosis. Persons exposed to opioids were matched with up to two unexposed persons on age and sex. Outcome was all-cause 180-days hospitalization. Cox proportional hazards models compared rates of hospitalization within 180 days between the exposed and unexposed and adjusted for potential confounders. RESULTS: Forty-two percent (31,619/75,471) of older people with dementia redeemed an opioid prescription after diagnosis. Among exposed, 7,356 (23.3%) were hospitalized within 180 days, compared with 7,618 (12.1%) of unexposed, and opioid use was associated with a 4-fold increased risk of hospitalization (fully adjusted hazard ratio: 3.86 (95% confidence interval, 3.72–4.01)), and 8-fold within the first 14 days ((7.77 (7.15–8.45)). Exposed were more often admitted due to fractures, infections, and cardiovascular events. CONCLUSION: Opioid use was associated with increased risk of hospitalization, which may be due to the opioid, the indication, or both. This observation calls for further research into potential harmful effects associated with opioid use as it can have important implications for patient safety.