Multivariate Analysis of the Impact of Alzheimer’s Disease on the Cost of Long-Term Care

Background: The global number of individuals living with dementia is projected to rise from 57.4 million in 2019 to 152.8 million by 2050. Alongside this increase, the worldwide economic burden of dementia continues to grow, with the overall societal cost estimated at US$1313 billion in 2019—substantially higher than earlier projections. Objectives: To analyze the impact of dementia on long-term-care costs, we conducted a multivariate analysis to take into account overlaps with various other diseases. Methods: In this study, we conducted a multivariate analysis to assess the effect of major diseases on annual expenditure on long-term care by linking Japanese National Health Insurance and long-term-care insurance claims. Results: In a two-part analysis using a hurdle model, the first stage of multivariate logistic regression analysis of the presence or absence of disease showed that Parkinson’s disease had the highest multivariate-adjusted odds ratio, followed by Alzheimer’s disease and schizophrenia. In the second stage of the generalized linear model with log link–Gamma analysis of residents with positive costs, the disease with the highest exponential function (exp(b)) was Alzheimer’s disease, followed by stroke sequelae. Conclusions: To examine the impact of dementia on long-term-care costs, it is necessary to use multivariate analysis to avoid overlap with other diseases.