Dementia Increases the Risks of Acute Organ Dysfunction, Severe Sepsis and Mortality in Hospitalized Older Patients: A National Population-Based Study

Background: Dementia increases the risk of death in older patients hospitalized for acute illnesses. However, the effect of dementia on the risks of developing acute organ dysfunction and severe sepsis as well as on the risk of hospital mortality in hospitalized older patients remains unknown, especially when treatments for these life-threatening situations are considered. Methods: In this population-based cohort study, we analyzed 41,672 older (≥65 years) patients, including 3,487 (8.4%) with dementia, from the first-time admission claim data between 2005 and 2007 for a nationally representative sample of one million beneficiaries enrolled in the Taiwan National Health Insurance Research Database. Outcomes included acute organ dysfunction, severe sepsis, and hospital mortality. The effect of dementia on outcomes was assessed using multivariable logistic regression. Results: Dementia was associated with a 32% higher risk of acute organ dysfunction (adjusted odds ratio [aOR] 1.32, 95% confidence interval [CI] 1.19–1.46), a 50% higher risk of severe sepsis (aOR 1.50, 95% CI 1.32–1.69) and a 28% higher risk of hospital mortality (aOR 1.28, 95% CI 1.10–1.48) after controlling age, sex, surgical condition, comorbidity, principal diagnosis, infection status, hospital level, and length of hospital stay. However, the significant adverse effect of dementia on hospital mortality disappeared when life-support treatments, including vasopressor use, hemodialysis, mechanical ventilation, and intensive care, were also controlled. Conclusions: In hospitalized older patients, the presence of dementia increased the risks of acute organ dysfunction, severe sepsis and hospital mortality. However, after intervention using life-support treatments, dementia only exhibited a minor role on short-term mortality.