Discrepancy Between Self- and Proxy-Rated Pain in Alzheimer's Disease: Results from the Danish Alzheimer Intervention Study

Objectives To investigate the prevalence of self- and proxy-reported pain in a cohort with Alzheimer's disease (AD) and to identify characteristics of individuals with AD reporting pain. Design Data were collected at the baseline visit of the Danish Alzheimer Intervention Study. Setting Community. Participants Three hundred twenty-one community-living individuals with AD (MMSE = 20) and their primary caregivers. Measurements Pain was assessed as part of the EuroQol EQ-5D (caregiver- and self-rated). The Cornell Scale for Depression in Dementia, Quality of Life in Alzheimer's Disease Scale, EQ-5D visual analog scale, Mini-Mental State Examination, and Neuropsychiatric Inventory Questionnaire were also used. Results Fair agreement was found between self- and proxy ratings on pain (kappa = 0.34). Thirty-three percent of individuals with AD reported pain, whereas caregivers reported that 52% had pain (P < .001). Individuals who had self- or proxy-rated pain were significantly more likely to be female, had more depressive and other neuropsychiatric symptoms, and rated their quality of life lower. Conclusion Self- and proxy-reported pain differ in individuals with mild AD, with proxies rating more pain than the individuals with AD. Self- and proxy-rated pain was significantly associated with more neuropsychiatric and depressive symptoms and lower quality of life. In general, this study indicates that pain occurs frequently even in individuals with mild AD and that pain assessment may require self- and proxy report to identify individuals with need for possible treatment.