Diagnoses indicating pain and analgesic drug prescription in patients with dementia: a comparison to age- and sex-matched controls

BACKGROUND: The evidence of undertreatment of pain in patients with dementia is inconsistent. This may largely be due to methodological differences and shortcomings of studies. In a large cohort of patients with incident dementia and age- and sex-matched controls we examined (1) how often they receive diagnoses indicating pain, (2) how often they receive analgesics and (3) in which agents and formulations. METHODS: Using health insurance claims data we identified 1,848 patients with a first diagnosis of dementia aged ≥ 65 years and 7,385 age- and sex-matched controls. We analysed differences in diagnoses indicating pain and analgesic drugs prescribed between these two groups within the incidence year. We further fitted logistic regression models and stepwise adjusted for several covariates to study the relation between dementia and analgesics. RESULTS: On average, patients were 78.7 years old (48% female). The proportions receiving at least one diagnosis indicating pain were similar between the dementia and control group (74.4% vs. 72.5%; p = 0.11). The proportion who received analgesics was higher in patients with dementia in the crude analysis (47.5% vs. 44.7%; OR: 1.12; 95% CI: 1.01-1.24), but was significantly lower when adjusted for socio-demographic variables, care dependency, comorbidities and diagnoses indicating pain (OR: 0.78; 95% CI: 0.68-0.88). Analgesics in liquid form such as metamizole and tramadol were more often used in dementia. CONCLUSIONS: Our findings show a comparable documentation of diagnoses indicating pain in persons with incident dementia compared to those without. However, there still seems to be an undertreatment of pain in patients with dementia. Irrespective of dementia, analgesics seem to be more often prescribed to sicker patients and to control pain in the context of mobility.