Assessing advanced cancer pain in older adults with dementia at the end-of-life.

Aim: To assess advanced cancer pain in older adults with dementia at the end-of-life.

Background: Self-report is the gold standard for pain assessment; however, people with Alzheimer's disease may lose the ability to report pain. Biochemical and neuropathological changes occur in Alzheimer's disease that impairs the affective, sensory, and motor pain processing regions of the brain. Because people with severe Alzheimer's disease may lose the ability to report their sensory and emotional response to pain verbally, external motor displays of pain, such as grimacing, have been suggested for use in people with Alzheimer's disease.

Design: Between groups cross sectional study.

Method: Retrospective chart audits of people with Alzheimer's disease in nine nursing homes in the US in 2009. Participants were nursing home residents (n = 48) with mild to very severe dementia, pain and cognitive measures were collected during the final 3 months of life. The primary outcome variable was the discomfort behaviour scale score (a measure of observed pain behaviour) and the main predictor variable was the cognitive performance scale score (a measure of Alzheimer's disease severity). Medication administration (opioid, non-narcotic, and psychotropic medications) recorded over the final 2 weeks of life was collected as a covariate of interest.

Results: Alzheimer's disease severity was negatively associated with pain behaviours. Post hoc procedures showed that this difference was due to the difference in pain behaviours between individuals with moderate and very severe Alzheimer's disease. Total amount of opioid analgesic, total number of doses of non-narcotic medications, and psychotropic medications administered over the last 2 weeks of life were not statistically significantly correlated with pain behaviour. An inverse correlation was found between cognitive ability (Cognitive Performance Scale score) and total amount of opioid medication indicating that individuals with severe Alzheimer's disease received less opioid.

Conclusion: Because people with worsening Alzheimer's disease have fewer pain behaviours, assessing pain using behavioural indicators can be a challenge. Improving methods to assess for pain in people with Alzheimer's disease is of critical public health importance. Moreover, future studies are urgently needed to further examine the sensory, emotional, and behavioural responses to pain in people with Alzheimer's disease.