Neuropsychiatric symptoms in patients with dementia and the longitudinal costs of informal care in the Cache County population

Severity of dementia and neuropsychiatric symptoms contribute to increasing informal care costs. We examined which neuropsychiatric symptoms subdomains (NPS-SD) were associated with informal costs in a population-based sample. Dementia progression and informal costs (2015 dollars) were estimated from the Cache County Dementia Progression Study. Overall NPS and specific NPS-SD were assessed with the Neuropsychiatric Inventory. Generalized Estimating Equations (GEE with gamma-distribution/log-link) modeled the relationship between NPS-SDs and informal cost trajectories. Two hundred eighty participants (52.1% female; age M = 85.67, SD = 5.60) exhibited an adjusted cost increase of 5.6% (P = .005), 6.4% (P