OBJECTIVES: Individuals with Alzheimer’s disease or dementia require long-term and intensive care, leading to high medical expenditures and disease burden, which can be exacerbated by severe infections. However, little is known about the risk of severe infections among individuals with Alzheimer’s disease or dementia. Therefore, this study aimed to examine their patterns of severe infections, and identify factors associated with the risk, number, and cost of infection-related hospitalization.

METHODS: Individuals with Alzheimer’s disease or dementia in 2019 were identified from the National Health Insurance (NHI) claims data, and 10,000 subjects were randomly selected from them for further analysis. Four types of infections were included: septicemia, bacterial infection, fungal infection, and viral infection. Logistic regression model was adopted to identify factors associated with the risk of infection-related hospitalization. Generalized linear models were used to examine factors associated with number and cost of infection-related hospitalization.

RESULTS: The majority of the sample were more than 80 years old and female. 17% of them had infection-related hospitalizations in 2019. The most common infection type was bacterial infection, followed by septicemia. The average number and cost of the hospitalization were 0.27 and US$4,359, respectively. Older age, being male, being poor, higher Charlson Comorbidity Index score, worse continuity of care, and history of infection-related hospitalization were associated with a higher risk of infection-related hospitalization. Being male and history of infection-related hospital admission were correlated with higher number and cost of hospitalization.

CONCLUSIONS: The findings of this study demonstrated that individuals with Alzheimer's disease or dementia were at a high risk of infection-related hospitalization. Age, sex, socioeconomic status, comorbidities, continuity of care, and history of infection-related hospitalization were associated with the risk. The information is of help to identify high-risk individuals and to plan preventive measures in the disease management of this patient group.